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authorIngo Molnar <mingo@elte.hu>2009-09-07 08:19:51 +0200
committerIngo Molnar <mingo@elte.hu>2009-09-07 08:19:51 +0200
commita1922ed661ab2c1637d0b10cde933bd9cd33d965 (patch)
tree0f1777542b385ebefd30b3586d830fd8ed6fda5b /kernel/trace
parent75e33751ca8bbb72dd6f1a74d2810ddc8cbe4bdf (diff)
parentd28daf923ac5e4a0d7cecebae56f3e339189366b (diff)
downloadlinux-2.6.38-lt-ux500-a1922ed661ab2c1637d0b10cde933bd9cd33d965.tar.gz
Merge branch 'tracing/core' into tracing/hw-breakpoints
Conflicts: arch/Kconfig kernel/trace/trace.h Merge reason: resolve the conflicts, plus adopt to the new ring-buffer APIs. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/trace')
-rw-r--r--kernel/trace/Kconfig27
-rw-r--r--kernel/trace/blktrace.c25
-rw-r--r--kernel/trace/ftrace.c215
-rw-r--r--kernel/trace/kmemtrace.c149
-rw-r--r--kernel/trace/ring_buffer.c1437
-rw-r--r--kernel/trace/ring_buffer_benchmark.c45
-rw-r--r--kernel/trace/trace.c736
-rw-r--r--kernel/trace/trace.h87
-rw-r--r--kernel/trace/trace_boot.c16
-rw-r--r--kernel/trace/trace_event_profile.c2
-rw-r--r--kernel/trace/trace_event_types.h3
-rw-r--r--kernel/trace/trace_events.c178
-rw-r--r--kernel/trace/trace_events_filter.c292
-rw-r--r--kernel/trace/trace_export.c28
-rw-r--r--kernel/trace/trace_functions.c17
-rw-r--r--kernel/trace/trace_functions_graph.c213
-rw-r--r--kernel/trace/trace_irqsoff.c3
-rw-r--r--kernel/trace/trace_mmiotrace.c10
-rw-r--r--kernel/trace/trace_output.c3
-rw-r--r--kernel/trace/trace_power.c22
-rw-r--r--kernel/trace/trace_printk.c28
-rw-r--r--kernel/trace/trace_sched_switch.c59
-rw-r--r--kernel/trace/trace_sched_wakeup.c7
-rw-r--r--kernel/trace/trace_selftest.c1
-rw-r--r--kernel/trace/trace_stack.c54
-rw-r--r--kernel/trace/trace_stat.c53
-rw-r--r--kernel/trace/trace_stat.h2
-rw-r--r--kernel/trace/trace_syscalls.c471
-rw-r--r--kernel/trace/trace_workqueue.c32
29 files changed, 2829 insertions, 1386 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index ae048a2dbbe..5efeb4229ea 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -18,6 +18,13 @@ config HAVE_FUNCTION_TRACER
config HAVE_FUNCTION_GRAPH_TRACER
bool
+config HAVE_FUNCTION_GRAPH_FP_TEST
+ bool
+ help
+ An arch may pass in a unique value (frame pointer) to both the
+ entering and exiting of a function. On exit, the value is compared
+ and if it does not match, then it will panic the kernel.
+
config HAVE_FUNCTION_TRACE_MCOUNT_TEST
bool
help
@@ -34,7 +41,7 @@ config HAVE_FTRACE_MCOUNT_RECORD
config HAVE_HW_BRANCH_TRACER
bool
-config HAVE_FTRACE_SYSCALLS
+config HAVE_SYSCALL_TRACEPOINTS
bool
config TRACER_MAX_TRACE
@@ -53,9 +60,14 @@ config EVENT_TRACING
bool
config CONTEXT_SWITCH_TRACER
- select MARKERS
bool
+config RING_BUFFER_ALLOW_SWAP
+ bool
+ help
+ Allow the use of ring_buffer_swap_cpu.
+ Adds a very slight overhead to tracing when enabled.
+
# All tracer options should select GENERIC_TRACER. For those options that are
# enabled by all tracers (context switch and event tracer) they select TRACING.
# This allows those options to appear when no other tracer is selected. But the
@@ -121,6 +133,7 @@ config FUNCTION_GRAPH_TRACER
bool "Kernel Function Graph Tracer"
depends on HAVE_FUNCTION_GRAPH_TRACER
depends on FUNCTION_TRACER
+ depends on !X86_32 || !CC_OPTIMIZE_FOR_SIZE
default y
help
Enable the kernel to trace a function at both its return
@@ -139,6 +152,7 @@ config IRQSOFF_TRACER
select TRACE_IRQFLAGS
select GENERIC_TRACER
select TRACER_MAX_TRACE
+ select RING_BUFFER_ALLOW_SWAP
help
This option measures the time spent in irqs-off critical
sections, with microsecond accuracy.
@@ -160,6 +174,7 @@ config PREEMPT_TRACER
depends on PREEMPT
select GENERIC_TRACER
select TRACER_MAX_TRACE
+ select RING_BUFFER_ALLOW_SWAP
help
This option measures the time spent in preemption off critical
sections, with microsecond accuracy.
@@ -203,7 +218,7 @@ config ENABLE_DEFAULT_TRACERS
config FTRACE_SYSCALLS
bool "Trace syscalls"
- depends on HAVE_FTRACE_SYSCALLS
+ depends on HAVE_SYSCALL_TRACEPOINTS
select GENERIC_TRACER
select KALLSYMS
help
@@ -218,13 +233,13 @@ config BOOT_TRACER
the timings of the initcalls and traces key events and the identity
of tasks that can cause boot delays, such as context-switches.
- Its aim is to be parsed by the /scripts/bootgraph.pl tool to
+ Its aim is to be parsed by the scripts/bootgraph.pl tool to
produce pretty graphics about boot inefficiencies, giving a visual
representation of the delays during initcalls - but the raw
/debug/tracing/trace text output is readable too.
- You must pass in ftrace=initcall to the kernel command line
- to enable this on bootup.
+ You must pass in initcall_debug and ftrace=initcall to the kernel
+ command line to enable this on bootup.
config TRACE_BRANCH_PROFILING
bool
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 39af8af6fc3..3eb159c277c 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -22,6 +22,7 @@
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/debugfs.h>
+#include <linux/smp_lock.h>
#include <linux/time.h>
#include <linux/uaccess.h>
@@ -64,13 +65,15 @@ static void trace_note(struct blk_trace *bt, pid_t pid, int action,
{
struct blk_io_trace *t;
struct ring_buffer_event *event = NULL;
+ struct ring_buffer *buffer = NULL;
int pc = 0;
int cpu = smp_processor_id();
bool blk_tracer = blk_tracer_enabled;
if (blk_tracer) {
+ buffer = blk_tr->buffer;
pc = preempt_count();
- event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK,
+ event = trace_buffer_lock_reserve(buffer, TRACE_BLK,
sizeof(*t) + len,
0, pc);
if (!event)
@@ -95,7 +98,7 @@ record_it:
memcpy((void *) t + sizeof(*t), data, len);
if (blk_tracer)
- trace_buffer_unlock_commit(blk_tr, event, 0, pc);
+ trace_buffer_unlock_commit(buffer, event, 0, pc);
}
}
@@ -178,6 +181,7 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
{
struct task_struct *tsk = current;
struct ring_buffer_event *event = NULL;
+ struct ring_buffer *buffer = NULL;
struct blk_io_trace *t;
unsigned long flags = 0;
unsigned long *sequence;
@@ -203,8 +207,9 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
if (blk_tracer) {
tracing_record_cmdline(current);
+ buffer = blk_tr->buffer;
pc = preempt_count();
- event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK,
+ event = trace_buffer_lock_reserve(buffer, TRACE_BLK,
sizeof(*t) + pdu_len,
0, pc);
if (!event)
@@ -251,7 +256,7 @@ record_it:
memcpy((void *) t + sizeof(*t), pdu_data, pdu_len);
if (blk_tracer) {
- trace_buffer_unlock_commit(blk_tr, event, 0, pc);
+ trace_buffer_unlock_commit(buffer, event, 0, pc);
return;
}
}
@@ -266,8 +271,8 @@ static void blk_trace_free(struct blk_trace *bt)
{
debugfs_remove(bt->msg_file);
debugfs_remove(bt->dropped_file);
- debugfs_remove(bt->dir);
relay_close(bt->rchan);
+ debugfs_remove(bt->dir);
free_percpu(bt->sequence);
free_percpu(bt->msg_data);
kfree(bt);
@@ -377,18 +382,8 @@ static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf,
static int blk_remove_buf_file_callback(struct dentry *dentry)
{
- struct dentry *parent = dentry->d_parent;
debugfs_remove(dentry);
- /*
- * this will fail for all but the last file, but that is ok. what we
- * care about is the top level buts->name directory going away, when
- * the last trace file is gone. Then we don't have to rmdir() that
- * manually on trace stop, so it nicely solves the issue with
- * force killing of running traces.
- */
-
- debugfs_remove(parent);
return 0;
}
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index bb60732ade0..8c804e24f96 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -291,7 +291,9 @@ function_stat_next(void *v, int idx)
pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK);
again:
- rec++;
+ if (idx != 0)
+ rec++;
+
if ((void *)rec >= (void *)&pg->records[pg->index]) {
pg = pg->next;
if (!pg)
@@ -766,7 +768,7 @@ static struct tracer_stat function_stats __initdata = {
.stat_show = function_stat_show
};
-static void ftrace_profile_debugfs(struct dentry *d_tracer)
+static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
{
struct ftrace_profile_stat *stat;
struct dentry *entry;
@@ -784,7 +786,6 @@ static void ftrace_profile_debugfs(struct dentry *d_tracer)
* The files created are permanent, if something happens
* we still do not free memory.
*/
- kfree(stat);
WARN(1,
"Could not allocate stat file for cpu %d\n",
cpu);
@@ -811,7 +812,7 @@ static void ftrace_profile_debugfs(struct dentry *d_tracer)
}
#else /* CONFIG_FUNCTION_PROFILER */
-static void ftrace_profile_debugfs(struct dentry *d_tracer)
+static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
{
}
#endif /* CONFIG_FUNCTION_PROFILER */
@@ -1015,71 +1016,35 @@ static int
__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
{
unsigned long ftrace_addr;
- unsigned long ip, fl;
+ unsigned long flag = 0UL;
ftrace_addr = (unsigned long)FTRACE_ADDR;
- ip = rec->ip;
-
/*
- * If this record is not to be traced and
- * it is not enabled then do nothing.
+ * If this record is not to be traced or we want to disable it,
+ * then disable it.
*
- * If this record is not to be traced and
- * it is enabled then disable it.
+ * If we want to enable it and filtering is off, then enable it.
*
+ * If we want to enable it and filtering is on, enable it only if
+ * it's filtered
*/
- if (rec->flags & FTRACE_FL_NOTRACE) {
- if (rec->flags & FTRACE_FL_ENABLED)
- rec->flags &= ~FTRACE_FL_ENABLED;
- else
- return 0;
-
- } else if (ftrace_filtered && enable) {
- /*
- * Filtering is on:
- */
-
- fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED);
-
- /* Record is filtered and enabled, do nothing */
- if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED))
- return 0;
-
- /* Record is not filtered or enabled, do nothing */
- if (!fl)
- return 0;
-
- /* Record is not filtered but enabled, disable it */
- if (fl == FTRACE_FL_ENABLED)
- rec->flags &= ~FTRACE_FL_ENABLED;
- else
- /* Otherwise record is filtered but not enabled, enable it */
- rec->flags |= FTRACE_FL_ENABLED;
- } else {
- /* Disable or not filtered */
-
- if (enable) {
- /* if record is enabled, do nothing */
- if (rec->flags & FTRACE_FL_ENABLED)
- return 0;
-
- rec->flags |= FTRACE_FL_ENABLED;
-
- } else {
+ if (enable && !(rec->flags & FTRACE_FL_NOTRACE)) {
+ if (!ftrace_filtered || (rec->flags & FTRACE_FL_FILTER))
+ flag = FTRACE_FL_ENABLED;
+ }
- /* if record is not enabled, do nothing */
- if (!(rec->flags & FTRACE_FL_ENABLED))
- return 0;
+ /* If the state of this record hasn't changed, then do nothing */
+ if ((rec->flags & FTRACE_FL_ENABLED) == flag)
+ return 0;
- rec->flags &= ~FTRACE_FL_ENABLED;
- }
+ if (flag) {
+ rec->flags |= FTRACE_FL_ENABLED;
+ return ftrace_make_call(rec, ftrace_addr);
}
- if (rec->flags & FTRACE_FL_ENABLED)
- return ftrace_make_call(rec, ftrace_addr);
- else
- return ftrace_make_nop(NULL, rec, ftrace_addr);
+ rec->flags &= ~FTRACE_FL_ENABLED;
+ return ftrace_make_nop(NULL, rec, ftrace_addr);
}
static void ftrace_replace_code(int enable)
@@ -1224,6 +1189,13 @@ static void ftrace_shutdown(int command)
return;
ftrace_start_up--;
+ /*
+ * Just warn in case of unbalance, no need to kill ftrace, it's not
+ * critical but the ftrace_call callers may be never nopped again after
+ * further ftrace uses.
+ */
+ WARN_ON_ONCE(ftrace_start_up < 0);
+
if (!ftrace_start_up)
command |= FTRACE_DISABLE_CALLS;
@@ -1367,7 +1339,6 @@ struct ftrace_iterator {
unsigned flags;
unsigned char buffer[FTRACE_BUFF_MAX+1];
unsigned buffer_idx;
- unsigned filtered;
};
static void *
@@ -1410,28 +1381,33 @@ static void *t_hash_start(struct seq_file *m, loff_t *pos)
{
struct ftrace_iterator *iter = m->private;
void *p = NULL;
+ loff_t l;
+
+ if (!(iter->flags & FTRACE_ITER_HASH))
+ *pos = 0;
iter->flags |= FTRACE_ITER_HASH;
- return t_hash_next(m, p, pos);
+ iter->hidx = 0;
+ for (l = 0; l <= *pos; ) {
+ p = t_hash_next(m, p, &l);
+ if (!p)
+ break;
+ }
+ return p;
}
static int t_hash_show(struct seq_file *m, void *v)
{
struct ftrace_func_probe *rec;
struct hlist_node *hnd = v;
- char str[KSYM_SYMBOL_LEN];
rec = hlist_entry(hnd, struct ftrace_func_probe, node);
if (rec->ops->print)
return rec->ops->print(m, rec->ip, rec->ops, rec->data);
- kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
- seq_printf(m, "%s:", str);
-
- kallsyms_lookup((unsigned long)rec->ops->func, NULL, NULL, NULL, str);
- seq_printf(m, "%s", str);
+ seq_printf(m, "%pf:%pf", (void *)rec->ip, (void *)rec->ops->func);
if (rec->data)
seq_printf(m, ":%p", rec->data);
@@ -1460,8 +1436,6 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
iter->pg = iter->pg->next;
iter->idx = 0;
goto retry;
- } else {
- iter->idx = -1;
}
} else {
rec = &iter->pg->records[iter->idx++];
@@ -1490,6 +1464,7 @@ static void *t_start(struct seq_file *m, loff_t *pos)
{
struct ftrace_iterator *iter = m->private;
void *p = NULL;
+ loff_t l;
mutex_lock(&ftrace_lock);
/*
@@ -1501,23 +1476,21 @@ static void *t_start(struct seq_file *m, loff_t *pos)
if (*pos > 0)
return t_hash_start(m, pos);
iter->flags |= FTRACE_ITER_PRINTALL;
- (*pos)++;
return iter;
}
if (iter->flags & FTRACE_ITER_HASH)
return t_hash_start(m, pos);
- if (*pos > 0) {
- if (iter->idx < 0)
- return p;
- (*pos)--;
- iter->idx--;
+ iter->pg = ftrace_pages_start;
+ iter->idx = 0;
+ for (l = 0; l <= *pos; ) {
+ p = t_next(m, p, &l);
+ if (!p)
+ break;
}
- p = t_next(m, p, pos);
-
- if (!p)
+ if (!p && iter->flags & FTRACE_ITER_FILTER)
return t_hash_start(m, pos);
return p;
@@ -1532,7 +1505,6 @@ static int t_show(struct seq_file *m, void *v)
{
struct ftrace_iterator *iter = m->private;
struct dyn_ftrace *rec = v;
- char str[KSYM_SYMBOL_LEN];
if (iter->flags & FTRACE_ITER_HASH)
return t_hash_show(m, v);
@@ -1545,9 +1517,7 @@ static int t_show(struct seq_file *m, void *v)
if (!rec)
return 0;
- kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
-
- seq_printf(m, "%s\n", str);
+ seq_printf(m, "%pf\n", (void *)rec->ip);
return 0;
}
@@ -1586,17 +1556,6 @@ ftrace_avail_open(struct inode *inode, struct file *file)
return ret;
}
-int ftrace_avail_release(struct inode *inode, struct file *file)
-{
- struct seq_file *m = (struct seq_file *)file->private_data;
- struct ftrace_iterator *iter = m->private;
-
- seq_release(inode, file);
- kfree(iter);
-
- return 0;
-}
-
static int
ftrace_failures_open(struct inode *inode, struct file *file)
{
@@ -1647,7 +1606,7 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
mutex_lock(&ftrace_regex_lock);
if ((file->f_mode & FMODE_WRITE) &&
- !(file->f_flags & O_APPEND))
+ (file->f_flags & O_TRUNC))
ftrace_filter_reset(enable);
if (file->f_mode & FMODE_READ) {
@@ -2263,7 +2222,11 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
read++;
cnt--;
- if (!(iter->flags & ~FTRACE_ITER_CONT)) {
+ /*
+ * If the parser haven't finished with the last write,
+ * continue reading the user input without skipping spaces.
+ */
+ if (!(iter->flags & FTRACE_ITER_CONT)) {
/* skip white space */
while (cnt && isspace(ch)) {
ret = get_user(ch, ubuf++);
@@ -2273,8 +2236,9 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
cnt--;
}
+ /* only spaces were written */
if (isspace(ch)) {
- file->f_pos += read;
+ *ppos += read;
ret = read;
goto out;
}
@@ -2297,19 +2261,18 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
}
if (isspace(ch)) {
- iter->filtered++;
iter->buffer[iter->buffer_idx] = 0;
ret = ftrace_process_regex(iter->buffer,
iter->buffer_idx, enable);
if (ret)
goto out;
iter->buffer_idx = 0;
- } else
+ } else {
iter->flags |= FTRACE_ITER_CONT;
+ iter->buffer[iter->buffer_idx++] = ch;
+ }
-
- file->f_pos += read;
-
+ *ppos += read;
ret = read;
out:
mutex_unlock(&ftrace_regex_lock);
@@ -2428,7 +2391,6 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
iter = file->private_data;
if (iter->buffer_idx) {
- iter->filtered++;
iter->buffer[iter->buffer_idx] = 0;
ftrace_match_records(iter->buffer, iter->buffer_idx, enable);
}
@@ -2459,14 +2421,14 @@ static const struct file_operations ftrace_avail_fops = {
.open = ftrace_avail_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = ftrace_avail_release,
+ .release = seq_release_private,
};
static const struct file_operations ftrace_failures_fops = {
.open = ftrace_failures_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = ftrace_avail_release,
+ .release = seq_release_private,
};
static const struct file_operations ftrace_filter_fops = {
@@ -2493,32 +2455,31 @@ int ftrace_graph_count;
unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
static void *
-g_next(struct seq_file *m, void *v, loff_t *pos)
+__g_next(struct seq_file *m, loff_t *pos)
{
unsigned long *array = m->private;
- int index = *pos;
-
- (*pos)++;
- if (index >= ftrace_graph_count)
+ if (*pos >= ftrace_graph_count)
return NULL;
+ return &array[*pos];
+}
- return &array[index];
+static void *
+g_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ (*pos)++;
+ return __g_next(m, pos);
}
static void *g_start(struct seq_file *m, loff_t *pos)
{
- void *p = NULL;
-
mutex_lock(&graph_lock);
/* Nothing, tell g_show to print all functions are enabled */
if (!ftrace_graph_count && !*pos)
return (void *)1;
- p = g_next(m, p, pos);
-
- return p;
+ return __g_next(m, pos);
}
static void g_stop(struct seq_file *m, void *p)
@@ -2529,7 +2490,6 @@ static void g_stop(struct seq_file *m, void *p)
static int g_show(struct seq_file *m, void *v)
{
unsigned long *ptr = v;
- char str[KSYM_SYMBOL_LEN];
if (!ptr)
return 0;
@@ -2539,9 +2499,7 @@ static int g_show(struct seq_file *m, void *v)
return 0;
}
- kallsyms_lookup(*ptr, NULL, NULL, NULL, str);
-
- seq_printf(m, "%s\n", str);
+ seq_printf(m, "%pf\n", v);
return 0;
}
@@ -2563,7 +2521,7 @@ ftrace_graph_open(struct inode *inode, struct file *file)
mutex_lock(&graph_lock);
if ((file->f_mode & FMODE_WRITE) &&
- !(file->f_flags & O_APPEND)) {
+ (file->f_flags & O_TRUNC)) {
ftrace_graph_count = 0;
memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs));
}
@@ -2582,6 +2540,14 @@ ftrace_graph_open(struct inode *inode, struct file *file)
}
static int
+ftrace_graph_release(struct inode *inode, struct file *file)
+{
+ if (file->f_mode & FMODE_READ)
+ seq_release(inode, file);
+ return 0;
+}
+
+static int
ftrace_set_func(unsigned long *array, int *idx, char *buffer)
{
struct dyn_ftrace *rec;
@@ -2710,9 +2676,10 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
}
static const struct file_operations ftrace_graph_fops = {
- .open = ftrace_graph_open,
- .read = seq_read,
- .write = ftrace_graph_write,
+ .open = ftrace_graph_open,
+ .read = seq_read,
+ .write = ftrace_graph_write,
+ .release = ftrace_graph_release,
};
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
@@ -3145,10 +3112,10 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
- if (ret || !write || (last_ftrace_enabled == ftrace_enabled))
+ if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
goto out;
- last_ftrace_enabled = ftrace_enabled;
+ last_ftrace_enabled = !!ftrace_enabled;
if (ftrace_enabled) {
diff --git a/kernel/trace/kmemtrace.c b/kernel/trace/kmemtrace.c
index 86cdf671d7e..81b1645c854 100644
--- a/kernel/trace/kmemtrace.c
+++ b/kernel/trace/kmemtrace.c
@@ -183,11 +183,9 @@ static void kmemtrace_stop_probes(void)
static int kmem_trace_init(struct trace_array *tr)
{
- int cpu;
kmemtrace_array = tr;
- for_each_cpu_mask(cpu, cpu_possible_map)
- tracing_reset(tr, cpu);
+ tracing_reset_online_cpus(tr);
kmemtrace_start_probes();
@@ -239,12 +237,52 @@ struct kmemtrace_user_event_alloc {
};
static enum print_line_t
-kmemtrace_print_alloc_user(struct trace_iterator *iter,
- struct kmemtrace_alloc_entry *entry)
+kmemtrace_print_alloc(struct trace_iterator *iter, int flags)
{
- struct kmemtrace_user_event_alloc *ev_alloc;
struct trace_seq *s = &iter->seq;
+ struct kmemtrace_alloc_entry *entry;
+ int ret;
+
+ trace_assign_type(entry, iter->ent);
+
+ ret = trace_seq_printf(s, "type_id %d call_site %pF ptr %lu "
+ "bytes_req %lu bytes_alloc %lu gfp_flags %lu node %d\n",
+ entry->type_id, (void *)entry->call_site, (unsigned long)entry->ptr,
+ (unsigned long)entry->bytes_req, (unsigned long)entry->bytes_alloc,
+ (unsigned long)entry->gfp_flags, entry->node);
+
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+kmemtrace_print_free(struct trace_iterator *iter, int flags)
+{
+ struct trace_seq *s = &iter->seq;
+ struct kmemtrace_free_entry *entry;
+ int ret;
+
+ trace_assign_type(entry, iter->ent);
+
+ ret = trace_seq_printf(s, "type_id %d call_site %pF ptr %lu\n",
+ entry->type_id, (void *)entry->call_site,
+ (unsigned long)entry->ptr);
+
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+kmemtrace_print_alloc_user(struct trace_iterator *iter, int flags)
+{
+ struct trace_seq *s = &iter->seq;
+ struct kmemtrace_alloc_entry *entry;
struct kmemtrace_user_event *ev;
+ struct kmemtrace_user_event_alloc *ev_alloc;
+
+ trace_assign_type(entry, iter->ent);
ev = trace_seq_reserve(s, sizeof(*ev));
if (!ev)
@@ -271,12 +309,14 @@ kmemtrace_print_alloc_user(struct trace_iterator *iter,
}
static enum print_line_t
-kmemtrace_print_free_user(struct trace_iterator *iter,
- struct kmemtrace_free_entry *entry)
+kmemtrace_print_free_user(struct trace_iterator *iter, int flags)
{
struct trace_seq *s = &iter->seq;
+ struct kmemtrace_free_entry *entry;
struct kmemtrace_user_event *ev;
+ trace_assign_type(entry, iter->ent);
+
ev = trace_seq_reserve(s, sizeof(*ev));
if (!ev)
return TRACE_TYPE_PARTIAL_LINE;
@@ -294,12 +334,14 @@ kmemtrace_print_free_user(struct trace_iterator *iter,
/* The two other following provide a more minimalistic output */
static enum print_line_t
-kmemtrace_print_alloc_compress(struct trace_iterator *iter,
- struct kmemtrace_alloc_entry *entry)
+kmemtrace_print_alloc_compress(struct trace_iterator *iter)
{
+ struct kmemtrace_alloc_entry *entry;
struct trace_seq *s = &iter->seq;
int ret;
+ trace_assign_type(entry, iter->ent);
+
/* Alloc entry */
ret = trace_seq_printf(s, " + ");
if (!ret)
@@ -345,29 +387,24 @@ kmemtrace_print_alloc_compress(struct trace_iterator *iter,
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- /* Node */
- ret = trace_seq_printf(s, "%4d ", entry->node);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- /* Call site */
- ret = seq_print_ip_sym(s, entry->call_site, 0);
+ /* Node and call site*/
+ ret = trace_seq_printf(s, "%4d %pf\n", entry->node,
+ (void *)entry->call_site);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- if (!trace_seq_printf(s, "\n"))
- return TRACE_TYPE_PARTIAL_LINE;
-
return TRACE_TYPE_HANDLED;
}
static enum print_line_t
-kmemtrace_print_free_compress(struct trace_iterator *iter,
- struct kmemtrace_free_entry *entry)
+kmemtrace_print_free_compress(struct trace_iterator *iter)
{
+ struct kmemtrace_free_entry *entry;
struct trace_seq *s = &iter->seq;
int ret;
+ trace_assign_type(entry, iter->ent);
+
/* Free entry */
ret = trace_seq_printf(s, " - ");
if (!ret)
@@ -401,19 +438,11 @@ kmemtrace_print_free_compress(struct trace_iterator *iter,
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- /* Skip node */
- ret = trace_seq_printf(s, " ");
+ /* Skip node and print call site*/
+ ret = trace_seq_printf(s, " %pf\n", (void *)entry->call_site);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- /* Call site */
- ret = seq_print_ip_sym(s, entry->call_site, 0);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- if (!trace_seq_printf(s, "\n"))
- return TRACE_TYPE_PARTIAL_LINE;
-
return TRACE_TYPE_HANDLED;
}
@@ -421,32 +450,31 @@ static enum print_line_t kmemtrace_print_line(struct trace_iterator *iter)
{
struct trace_entry *entry = iter->ent;
- switch (entry->type) {
- case TRACE_KMEM_ALLOC: {
- struct kmemtrace_alloc_entry *field;
-
- trace_assign_type(field, entry);
- if (kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL)
- return kmemtrace_print_alloc_compress(iter, field);
- else
- return kmemtrace_print_alloc_user(iter, field);
- }
-
- case TRACE_KMEM_FREE: {
- struct kmemtrace_free_entry *field;
-
- trace_assign_type(field, entry);
- if (kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL)
- return kmemtrace_print_free_compress(iter, field);
- else
- return kmemtrace_print_free_user(iter, field);
- }
+ if (!(kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL))
+ return TRACE_TYPE_UNHANDLED;
+ switch (entry->type) {
+ case TRACE_KMEM_ALLOC:
+ return kmemtrace_print_alloc_compress(iter);
+ case TRACE_KMEM_FREE:
+ return kmemtrace_print_free_compress(iter);
default:
return TRACE_TYPE_UNHANDLED;
}
}
+static struct trace_event kmem_trace_alloc = {
+ .type = TRACE_KMEM_ALLOC,
+ .trace = kmemtrace_print_alloc,
+ .binary = kmemtrace_print_alloc_user,
+};
+
+static struct trace_event kmem_trace_free = {
+ .type = TRACE_KMEM_FREE,
+ .trace = kmemtrace_print_free,
+ .binary = kmemtrace_print_free_user,
+};
+
static struct tracer kmem_tracer __read_mostly = {
.name = "kmemtrace",
.init = kmem_trace_init,
@@ -463,6 +491,21 @@ void kmemtrace_init(void)
static int __init init_kmem_tracer(void)
{
- return register_tracer(&kmem_tracer);
+ if (!register_ftrace_event(&kmem_trace_alloc)) {
+ pr_warning("Warning: could not register kmem events\n");
+ return 1;
+ }
+
+ if (!register_ftrace_event(&kmem_trace_free)) {
+ pr_warning("Warning: could not register kmem events\n");
+ return 1;
+ }
+
+ if (!register_tracer(&kmem_tracer)) {
+ pr_warning("Warning: could not register the kmem tracer\n");
+ return 1;
+ }
+
+ return 0;
}
device_initcall(init_kmem_tracer);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index dc4dc70171c..454e74e718c 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -206,6 +206,7 @@ EXPORT_SYMBOL_GPL(tracing_is_on);
#define RB_EVNT_HDR_SIZE (offsetof(struct ring_buffer_event, array))
#define RB_ALIGNMENT 4U
#define RB_MAX_SMALL_DATA (RB_ALIGNMENT * RINGBUF_TYPE_DATA_TYPE_LEN_MAX)
+#define RB_EVNT_MIN_SIZE 8U /* two 32bit words */
/* define RINGBUF_TYPE_DATA for 'case RINGBUF_TYPE_DATA:' */
#define RINGBUF_TYPE_DATA 0 ... RINGBUF_TYPE_DATA_TYPE_LEN_MAX
@@ -217,17 +218,12 @@ enum {
static inline int rb_null_event(struct ring_buffer_event *event)
{
- return event->type_len == RINGBUF_TYPE_PADDING
- && event->time_delta == 0;
-}
-
-static inline int rb_discarded_event(struct ring_buffer_event *event)
-{
- return event->type_len == RINGBUF_TYPE_PADDING && event->time_delta;
+ return event->type_len == RINGBUF_TYPE_PADDING && !event->time_delta;
}
static void rb_event_set_padding(struct ring_buffer_event *event)
{
+ /* padding has a NULL time_delta */
event->type_len = RINGBUF_TYPE_PADDING;
event->time_delta = 0;
}
@@ -321,6 +317,14 @@ struct buffer_data_page {
unsigned char data[]; /* data of buffer page */
};
+/*
+ * Note, the buffer_page list must be first. The buffer pages
+ * are allocated in cache lines, which means that each buffer
+ * page will be at the beginning of a cache line, and thus
+ * the least significant bits will be zero. We use this to
+ * add flags in the list struct pointers, to make the ring buffer
+ * lockless.
+ */
struct buffer_page {
struct list_head list; /* list of buffer pages */
local_t write; /* index for next write */
@@ -329,6 +333,21 @@ struct buffer_page {
struct buffer_data_page *page; /* Actual data page */
};
+/*
+ * The buffer page counters, write and entries, must be reset
+ * atomically when crossing page boundaries. To synchronize this
+ * update, two counters are inserted into the number. One is
+ * the actual counter for the write position or count on the page.
+ *
+ * The other is a counter of updaters. Before an update happens
+ * the update partition of the counter is incremented. This will
+ * allow the updater to update the counter atomically.
+ *
+ * The counter is 20 bits, and the state data is 12.
+ */
+#define RB_WRITE_MASK 0xfffff
+#define RB_WRITE_INTCNT (1 << 20)
+
static void rb_init_page(struct buffer_data_page *bpage)
{
local_set(&bpage->commit, 0);
@@ -402,19 +421,20 @@ int ring_buffer_print_page_header(struct trace_seq *s)
struct ring_buffer_per_cpu {
int cpu;
struct ring_buffer *buffer;
- spinlock_t reader_lock; /* serialize readers */
+ spinlock_t reader_lock; /* serialize readers */
raw_spinlock_t lock;
struct lock_class_key lock_key;
- struct list_head pages;
+ struct list_head *pages;
struct buffer_page *head_page; /* read from head */
struct buffer_page *tail_page; /* write to tail */
struct buffer_page *commit_page; /* committed pages */
struct buffer_page *reader_page;
- unsigned long nmi_dropped;
- unsigned long commit_overrun;
- unsigned long overrun;
- unsigned long read;
+ local_t commit_overrun;
+ local_t overrun;
local_t entries;
+ local_t committing;
+ local_t commits;
+ unsigned long read;
u64 write_stamp;
u64 read_stamp;
atomic_t record_disabled;
@@ -447,14 +467,19 @@ struct ring_buffer_iter {
};
/* buffer may be either ring_buffer or ring_buffer_per_cpu */
-#define RB_WARN_ON(buffer, cond) \
- ({ \
- int _____ret = unlikely(cond); \
- if (_____ret) { \
- atomic_inc(&buffer->record_disabled); \
- WARN_ON(1); \
- } \
- _____ret; \
+#define RB_WARN_ON(b, cond) \
+ ({ \
+ int _____ret = unlikely(cond); \
+ if (_____ret) { \
+ if (__same_type(*(b), struct ring_buffer_per_cpu)) { \
+ struct ring_buffer_per_cpu *__b = \
+ (void *)b; \
+ atomic_inc(&__b->buffer->record_disabled); \
+ } else \
+ atomic_inc(&b->record_disabled); \
+ WARN_ON(1); \
+ } \
+ _____ret; \
})
/* Up this if you want to test the TIME_EXTENTS and normalization */
@@ -486,6 +511,390 @@ void ring_buffer_normalize_time_stamp(struct ring_buffer *buffer,
}
EXPORT_SYMBOL_GPL(ring_buffer_normalize_time_stamp);
+/*
+ * Making the ring buffer lockless makes things tricky.
+ * Although writes only happen on the CPU that they are on,
+ * and they only need to worry about interrupts. Reads can
+ * happen on any CPU.
+ *
+ * The reader page is always off the ring buffer, but when the
+ * reader finishes with a page, it needs to swap its page with
+ * a new one from the buffer. The reader needs to take from
+ * the head (writes go to the tail). But if a writer is in overwrite
+ * mode and wraps, it must push the head page forward.
+ *
+ * Here lies the problem.
+ *
+ * The reader must be careful to replace only the head page, and
+ * not another one. As described at the top of the file in the
+ * ASCII art, the reader sets its old page to point to the next
+ * page after head. It then sets the page after head to point to
+ * the old reader page. But if the writer moves the head page
+ * during this operation, the reader could end up with the tail.
+ *
+ * We use cmpxchg to help prevent this race. We also do something
+ * special with the page before head. We set the LSB to 1.
+ *
+ * When the writer must push the page forward, it will clear the
+ * bit that points to the head page, move the head, and then set
+ * the bit that points to the new head page.
+ *
+ * We also don't want an interrupt coming in and moving the head
+ * page on another writer. Thus we use the second LSB to catch
+ * that too. Thus:
+ *
+ * head->list->prev->next bit 1 bit 0
+ * ------- -------
+ * Normal page 0 0
+ * Points to head page 0 1
+ * New head page 1 0
+ *
+ * Note we can not trust the prev pointer of the head page, because:
+ *
+ * +----+ +-----+ +-----+
+ * | |------>| T |---X--->| N |
+ * | |<------| | | |
+ * +----+ +-----+ +-----+
+ * ^ ^ |
+ * | +-----+ | |
+ * +----------| R |----------+ |
+ * | |<-----------+
+ * +-----+
+ *
+ * Key: ---X--> HEAD flag set in pointer
+ * T Tail page
+ * R Reader page
+ * N Next page
+ *
+ * (see __rb_reserve_next() to see where this happens)
+ *
+ * What the above shows is that the reader just swapped out
+ * the reader page with a page in the buffer, but before it
+ * could make the new header point back to the new page added
+ * it was preempted by a writer. The writer moved forward onto
+ * the new page added by the reader and is about to move forward
+ * again.
+ *
+ * You can see, it is legitimate for the previous pointer of
+ * the head (or any page) not to point back to itself. But only
+ * temporarially.
+ */
+
+#define RB_PAGE_NORMAL 0UL
+#define RB_PAGE_HEAD 1UL
+#define RB_PAGE_UPDATE 2UL
+
+
+#define RB_FLAG_MASK 3UL
+
+/* PAGE_MOVED is not part of the mask */
+#define RB_PAGE_MOVED 4UL
+
+/*
+ * rb_list_head - remove any bit
+ */
+static struct list_head *rb_list_head(struct list_head *list)
+{
+ unsigned long val = (unsigned long)list;
+
+ return (struct list_head *)(val & ~RB_FLAG_MASK);
+}
+
+/*
+ * rb_is_head_page - test if the give page is the head page
+ *
+ * Because the reader may move the head_page pointer, we can
+ * not trust what the head page is (it may be pointing to
+ * the reader page). But if the next page is a header page,
+ * its flags will be non zero.
+ */
+static int inline
+rb_is_head_page(struct ring_buffer_per_cpu *cpu_buffer,
+ struct buffer_page *page, struct list_head *list)
+{
+ unsigned long val;
+
+ val = (unsigned long)list->next;
+
+ if ((val & ~RB_FLAG_MASK) != (unsigned long)&page->list)
+ return RB_PAGE_MOVED;
+
+ return val & RB_FLAG_MASK;
+}
+
+/*
+ * rb_is_reader_page
+ *
+ * The unique thing about the reader page, is that, if the
+ * writer is ever on it, the previous pointer never points
+ * back to the reader page.
+ */
+static int rb_is_reader_page(struct buffer_page *page)
+{
+ struct list_head *list = page->list.prev;
+
+ return rb_list_head(list->next) != &page->list;
+}
+
+/*
+ * rb_set_list_to_head - set a list_head to be pointing to head.
+ */
+static void rb_set_list_to_head(struct ring_buffer_per_cpu *cpu_buffer,
+ struct list_head *list)
+{
+ unsigned long *ptr;
+
+ ptr = (unsigned long *)&list->next;
+ *ptr |= RB_PAGE_HEAD;
+ *ptr &= ~RB_PAGE_UPDATE;
+}
+
+/*
+ * rb_head_page_activate - sets up head page
+ */
+static void rb_head_page_activate(struct ring_buffer_per_cpu *cpu_buffer)
+{
+ struct buffer_page *head;
+
+ head = cpu_buffer->head_page;
+ if (!head)
+ return;
+
+ /*
+ * Set the previous list pointer to have the HEAD flag.
+ */
+ rb_set_list_to_head(cpu_buffer, head->list.prev);
+}
+
+static void rb_list_head_clear(struct list_head *list)
+{
+ unsigned long *ptr = (unsigned long *)&list->next;
+
+ *ptr &= ~RB_FLAG_MASK;
+}
+
+/*
+ * rb_head_page_dactivate - clears head page ptr (for free list)
+ */
+static void
+rb_head_page_deactivate(struct ring_buffer_per_cpu *cpu_buffer)
+{
+ struct list_head *hd;
+
+ /* Go through the whole list and clear any pointers found. */
+ rb_list_head_clear(cpu_buffer->pages);
+
+ list_for_each(hd, cpu_buffer->pages)
+ rb_list_head_clear(hd);
+}
+
+static int rb_head_page_set(struct ring_buffer_per_cpu *cpu_buffer,
+ struct buffer_page *head,
+ struct buffer_page *prev,
+ int old_flag, int new_flag)
+{
+ struct list_head *list;
+ unsigned long val = (unsigned long)&head->list;
+ unsigned long ret;
+
+ list = &prev->list;
+
+ val &= ~RB_FLAG_MASK;
+
+ ret = (unsigned long)cmpxchg(&list->next,
+ val | old_flag, val | new_flag);
+
+ /* check if the reader took the page */
+ if ((ret & ~RB_FLAG_MASK) != val)
+ return RB_PAGE_MOVED;
+
+ return ret & RB_FLAG_MASK;
+}
+
+static int rb_head_page_set_update(struct ring_buffer_per_cpu *cpu_buffer,
+ struct buffer_page *head,
+ struct buffer_page *prev,
+ int old_flag)
+{
+ return rb_head_page_set(cpu_buffer, head, prev,
+ old_flag, RB_PAGE_UPDATE);
+}
+
+static int rb_head_page_set_head(struct ring_buffer_per_cpu *cpu_buffer,
+ struct buffer_page *head,
+ struct buffer_page *prev,
+ int old_flag)
+{
+ return rb_head_page_set(cpu_buffer, head, prev,
+ old_flag, RB_PAGE_HEAD);
+}
+
+static int rb_head_page_set_normal(struct ring_buffer_per_cpu *cpu_buffer,
+ struct buffer_page *head,
+ struct buffer_page *prev,
+ int old_flag)
+{
+ return rb_head_page_set(cpu_buffer, head, prev,
+ old_flag, RB_PAGE_NORMAL);
+}
+
+static inline void rb_inc_page(struct ring_buffer_per_cpu *cpu_buffer,
+ struct buffer_page **bpage)
+{
+ struct list_head *p = rb_list_head((*bpage)->list.next);
+
+ *bpage = list_entry(p, struct buffer_page, list);
+}
+
+static struct buffer_page *
+rb_set_head_page(struct ring_buffer_per_cpu *cpu_buffer)
+{
+ struct buffer_page *head;
+ struct buffer_page *page;
+ struct list_head *list;
+ int i;
+
+ if (RB_WARN_ON(cpu_buffer, !cpu_buffer->head_page))
+ return NULL;
+
+ /* sanity check */
+ list = cpu_buffer->pages;
+ if (RB_WARN_ON(cpu_buffer, rb_list_head(list->prev->next) != list))
+ return NULL;
+
+ page = head = cpu_buffer->head_page;
+ /*
+ * It is possible that the writer moves the header behind
+ * where we started, and we miss in one loop.
+ * A second loop should grab the header, but we'll do
+ * three loops just because I'm paranoid.
+ */
+ for (i = 0; i < 3; i++) {
+ do {
+ if (rb_is_head_page(cpu_buffer, page, page->list.prev)) {
+ cpu_buffer->head_page = page;
+ return page;
+ }
+ rb_inc_page(cpu_buffer, &page);
+ } while (page != head);
+ }
+
+ RB_WARN_ON(cpu_buffer, 1);
+
+ return NULL;
+}
+
+static int rb_head_page_replace(struct buffer_page *old,
+ struct buffer_page *new)
+{
+ unsigned long *ptr = (unsigned long *)&old->list.prev->next;
+ unsigned long val;
+ unsigned long ret;
+
+ val = *ptr & ~RB_FLAG_MASK;
+ val |= RB_PAGE_HEAD;
+
+ ret = cmpxchg(ptr, val, &new->list);
+
+ return ret == val;
+}
+
+/*
+ * rb_tail_page_update - move the tail page forward
+ *
+ * Returns 1 if moved tail page, 0 if someone else did.
+ */
+static int rb_tail_page_update(struct ring_buffer_per_cpu *cpu_buffer,
+ struct buffer_page *tail_page,
+ struct buffer_page *next_page)
+{
+ struct buffer_page *old_tail;
+ unsigned long old_entries;
+ unsigned long old_write;
+ int ret = 0;
+
+ /*
+ * The tail page now needs to be moved forward.
+ *
+ * We need to reset the tail page, but without messing
+ * with possible erasing of data brought in by interrupts
+ * that have moved the tail page and are currently on it.
+ *
+ * We add a counter to the write field to denote this.
+ */
+ old_write = local_add_return(RB_WRITE_INTCNT, &next_page->write);
+ old_entries = local_add_return(RB_WRITE_INTCNT, &next_page->entries);
+
+ /*
+ * Just make sure we have seen our old_write and synchronize
+ * with any interrupts that come in.
+ */
+ barrier();
+
+ /*
+ * If the tail page is still the same as what we think
+ * it is, then it is up to us to update the tail
+ * pointer.
+ */
+ if (tail_page == cpu_buffer->tail_page) {
+ /* Zero the write counter */
+ unsigned long val = old_write & ~RB_WRITE_MASK;
+ unsigned long eval = old_entries & ~RB_WRITE_MASK;
+
+ /*
+ * This will only succeed if an interrupt did
+ * not come in and change it. In which case, we
+ * do not want to modify it.
+ *
+ * We add (void) to let the compiler know that we do not care
+ * about the return value of these functions. We use the
+ * cmpxchg to only update if an interrupt did not already
+ * do it for us. If the cmpxchg fails, we don't care.
+ */
+ (void)local_cmpxchg(&next_page->write, old_write, val);
+ (void)local_cmpxchg(&next_page->entries, old_entries, eval);
+
+ /*
+ * No need to worry about races with clearing out the commit.
+ * it only can increment when a commit takes place. But that
+ * only happens in the outer most nested commit.
+ */
+ local_set(&next_page->page->commit, 0);
+
+ old_tail = cmpxchg(&cpu_buffer->tail_page,
+ tail_page, next_page);
+
+ if (old_tail == tail_page)
+ ret = 1;
+ }
+
+ return ret;
+}
+
+static int rb_check_bpage(struct ring_buffer_per_cpu *cpu_buffer,
+ struct buffer_page *bpage)
+{
+ unsigned long val = (unsigned long)bpage;
+
+ if (RB_WARN_ON(cpu_buffer, val & RB_FLAG_MASK))
+ return 1;
+
+ return 0;
+}
+
+/**
+ * rb_check_list - make sure a pointer to a list has the last bits zero
+ */
+static int rb_check_list(struct ring_buffer_per_cpu *cpu_buffer,
+ struct list_head *list)
+{
+ if (RB_WARN_ON(cpu_buffer, rb_list_head(list->prev) != list->prev))
+ return 1;
+ if (RB_WARN_ON(cpu_buffer, rb_list_head(list->next) != list->next))
+ return 1;
+ return 0;
+}
+
/**
* check_pages - integrity check of buffer pages
* @cpu_buffer: CPU buffer with pages to test
@@ -495,14 +904,19 @@ EXPORT_SYMBOL_GPL(ring_buffer_normalize_time_stamp);
*/
static int rb_check_pages(struct ring_buffer_per_cpu *cpu_buffer)
{
- struct list_head *head = &cpu_buffer->pages;
+ struct list_head *head = cpu_buffer->pages;
struct buffer_page *bpage, *tmp;
+ rb_head_page_deactivate(cpu_buffer);
+
if (RB_WARN_ON(cpu_buffer, head->next->prev != head))
return -1;
if (RB_WARN_ON(cpu_buffer, head->prev->next != head))
return -1;
+ if (rb_check_list(cpu_buffer, head))
+ return -1;
+
list_for_each_entry_safe(bpage, tmp, head, list) {
if (RB_WARN_ON(cpu_buffer,
bpage->list.next->prev != &bpage->list))
@@ -510,25 +924,33 @@ static int rb_check_pages(struct ring_buffer_per_cpu *cpu_buffer)
if (RB_WARN_ON(cpu_buffer,
bpage->list.prev->next != &bpage->list))
return -1;
+ if (rb_check_list(cpu_buffer, &bpage->list))
+ return -1;
}
+ rb_head_page_activate(cpu_buffer);
+
return 0;
}
static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
unsigned nr_pages)
{
- struct list_head *head = &cpu_buffer->pages;
struct buffer_page *bpage, *tmp;
unsigned long addr;
LIST_HEAD(pages);
unsigned i;
+ WARN_ON(!nr_pages);
+
for (i = 0; i < nr_pages; i++) {
bpage = kzalloc_node(ALIGN(sizeof(*bpage), cache_line_size()),
GFP_KERNEL, cpu_to_node(cpu_buffer->cpu));
if (!bpage)
goto free_pages;
+
+ rb_check_bpage(cpu_buffer, bpage);
+
list_add(&bpage->list, &pages);
addr = __get_free_page(GFP_KERNEL);
@@ -538,7 +960,13 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
rb_init_page(bpage->page);
}
- list_splice(&pages, head);
+ /*
+ * The ring buffer page list is a circular list that does not
+ * start and end with a list head. All page list items point to
+ * other pages.
+ */
+ cpu_buffer->pages = pages.next;
+ list_del(&pages);
rb_check_pages(cpu_buffer);
@@ -570,13 +998,14 @@ rb_allocate_cpu_buffer(struct ring_buffer *buffer, int cpu)
spin_lock_init(&cpu_buffer->reader_lock);
lockdep_set_class(&cpu_buffer->reader_lock, buffer->reader_lock_key);
cpu_buffer->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
- INIT_LIST_HEAD(&cpu_buffer->pages);
bpage = kzalloc_node(ALIGN(sizeof(*bpage), cache_line_size()),
GFP_KERNEL, cpu_to_node(cpu));
if (!bpage)
goto fail_free_buffer;
+ rb_check_bpage(cpu_buffer, bpage);
+
cpu_buffer->reader_page = bpage;
addr = __get_free_page(GFP_KERNEL);
if (!addr)
@@ -591,9 +1020,11 @@ rb_allocate_cpu_buffer(struct ring_buffer *buffer, int cpu)
goto fail_free_reader;
cpu_buffer->head_page
- = list_entry(cpu_buffer->pages.next, struct buffer_page, list);
+ = list_entry(cpu_buffer->pages, struct buffer_page, list);
cpu_buffer->tail_page = cpu_buffer->commit_page = cpu_buffer->head_page;
+ rb_head_page_activate(cpu_buffer);
+
return cpu_buffer;
fail_free_reader:
@@ -606,24 +1037,25 @@ rb_allocate_cpu_buffer(struct ring_buffer *buffer, int cpu)
static void rb_free_cpu_buffer(struct ring_buffer_per_cpu *cpu_buffer)
{
- struct list_head *head = &cpu_buffer->pages;
+ struct list_head *head = cpu_buffer->pages;
struct buffer_page *bpage, *tmp;
free_buffer_page(cpu_buffer->reader_page);
- list_for_each_entry_safe(bpage, tmp, head, list) {
- list_del_init(&bpage->list);
+ rb_head_page_deactivate(cpu_buffer);
+
+ if (head) {
+ list_for_each_entry_safe(bpage, tmp, head, list) {
+ list_del_init(&bpage->list);
+ free_buffer_page(bpage);
+ }
+ bpage = list_entry(head, struct buffer_page, list);
free_buffer_page(bpage);
}
+
kfree(cpu_buffer);
}
-/*
- * Causes compile errors if the struct buffer_page gets bigger
- * than the struct page.
- */
-extern int ring_buffer_page_too_big(void);
-
#ifdef CONFIG_HOTPLUG_CPU
static int rb_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu);
@@ -646,11 +1078,6 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
int bsize;
int cpu;
- /* Paranoid! Optimizes out when all is well */
- if (sizeof(struct buffer_page) > sizeof(struct page))
- ring_buffer_page_too_big();
-
-
/* keep it in its own cache line */
buffer = kzalloc(ALIGN(sizeof(*buffer), cache_line_size()),
GFP_KERNEL);
@@ -666,8 +1093,8 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
buffer->reader_lock_key = key;
/* need at least two pages */
- if (buffer->pages == 1)
- buffer->pages++;
+ if (buffer->pages < 2)
+ buffer->pages = 2;
/*
* In case of non-hotplug cpu, if the ring-buffer is allocated
@@ -743,6 +1170,7 @@ ring_buffer_free(struct ring_buffer *buffer)
put_online_cpus();
+ kfree(buffer->buffers);
free_cpumask_var(buffer->cpumask);
kfree(buffer);
@@ -767,15 +1195,17 @@ rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned nr_pages)
atomic_inc(&cpu_buffer->record_disabled);
synchronize_sched();
+ rb_head_page_deactivate(cpu_buffer);
+
for (i = 0; i < nr_pages; i++) {
- if (RB_WARN_ON(cpu_buffer, list_empty(&cpu_buffer->pages)))
+ if (RB_WARN_ON(cpu_buffer, list_empty(cpu_buffer->pages)))
return;
- p = cpu_buffer->pages.next;
+ p = cpu_buffer->pages->next;
bpage = list_entry(p, struct buffer_page, list);
list_del_init(&bpage->list);
free_buffer_page(bpage);
}
- if (RB_WARN_ON(cpu_buffer, list_empty(&cpu_buffer->pages)))
+ if (RB_WARN_ON(cpu_buffer, list_empty(cpu_buffer->pages)))
return;
rb_reset_cpu(cpu_buffer);
@@ -797,15 +1227,19 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer,
atomic_inc(&cpu_buffer->record_disabled);
synchronize_sched();
+ spin_lock_irq(&cpu_buffer->reader_lock);
+ rb_head_page_deactivate(cpu_buffer);
+
for (i = 0; i < nr_pages; i++) {
if (RB_WARN_ON(cpu_buffer, list_empty(pages)))
return;
p = pages->next;
bpage = list_entry(p, struct buffer_page, list);
list_del_init(&bpage->list);
- list_add_tail(&bpage->list, &cpu_buffer->pages);
+ list_add_tail(&bpage->list, cpu_buffer->pages);
}
rb_reset_cpu(cpu_buffer);
+ spin_unlock_irq(&cpu_buffer->reader_lock);
rb_check_pages(cpu_buffer);
@@ -956,21 +1390,14 @@ rb_reader_event(struct ring_buffer_per_cpu *cpu_buffer)
}
static inline struct ring_buffer_event *
-rb_head_event(struct ring_buffer_per_cpu *cpu_buffer)
-{
- return __rb_page_index(cpu_buffer->head_page,
- cpu_buffer->head_page->read);
-}
-
-static inline struct ring_buffer_event *
rb_iter_head_event(struct ring_buffer_iter *iter)
{
return __rb_page_index(iter->head_page, iter->head);
}
-static inline unsigned rb_page_write(struct buffer_page *bpage)
+static inline unsigned long rb_page_write(struct buffer_page *bpage)
{
- return local_read(&bpage->write);
+ return local_read(&bpage->write) & RB_WRITE_MASK;
}
static inline unsigned rb_page_commit(struct buffer_page *bpage)
@@ -978,6 +1405,11 @@ static inline unsigned rb_page_commit(struct buffer_page *bpage)
return local_read(&bpage->page->commit);
}
+static inline unsigned long rb_page_entries(struct buffer_page *bpage)
+{
+ return local_read(&bpage->entries) & RB_WRITE_MASK;
+}
+
/* Size is determined by what has been commited */
static inline unsigned rb_page_size(struct buffer_page *bpage)
{
@@ -990,33 +1422,17 @@ rb_commit_index(struct ring_buffer_per_cpu *cpu_buffer)
return rb_page_commit(cpu_buffer->commit_page);
}
-static inline unsigned rb_head_size(struct ring_buffer_per_cpu *cpu_buffer)
-{
- return rb_page_commit(cpu_buffer->head_page);
-}
-
-static inline void rb_inc_page(struct ring_buffer_per_cpu *cpu_buffer,
- struct buffer_page **bpage)
-{
- struct list_head *p = (*bpage)->list.next;
-
- if (p == &cpu_buffer->pages)
- p = p->next;
-
- *bpage = list_entry(p, struct buffer_page, list);
-}
-
static inline unsigned
rb_event_index(struct ring_buffer_event *event)
{
unsigned long addr = (unsigned long)event;
- return (addr & ~PAGE_MASK) - (PAGE_SIZE - BUF_PAGE_SIZE);
+ return (addr & ~PAGE_MASK) - BUF_PAGE_HDR_SIZE;
}
static inline int
-rb_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
- struct ring_buffer_event *event)
+rb_event_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
+ struct ring_buffer_event *event)
{
unsigned long addr = (unsigned long)event;
unsigned long index;
@@ -1029,33 +1445,10 @@ rb_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
}
static void
-rb_set_commit_event(struct ring_buffer_per_cpu *cpu_buffer,
- struct ring_buffer_event *event)
-{
- unsigned long addr = (unsigned long)event;
- unsigned long index;
-
- index = rb_event_index(event);
- addr &= PAGE_MASK;
-
- while (cpu_buffer->commit_page->page != (void *)addr) {
- if (RB_WARN_ON(cpu_buffer,
- cpu_buffer->commit_page == cpu_buffer->tail_page))
- return;
- cpu_buffer->commit_page->page->commit =
- cpu_buffer->commit_page->write;
- rb_inc_page(cpu_buffer, &cpu_buffer->commit_page);
- cpu_buffer->write_stamp =
- cpu_buffer->commit_page->page->time_stamp;
- }
-
- /* Now set the commit to the event's index */
- local_set(&cpu_buffer->commit_page->page->commit, index);
-}
-
-static void
rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
{
+ unsigned long max_count;
+
/*
* We only race with interrupts and NMIs on this CPU.
* If we own the commit event, then we can commit
@@ -1065,9 +1458,16 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
* assign the commit to the tail.
*/
again:
+ max_count = cpu_buffer->buffer->pages * 100;
+
while (cpu_buffer->commit_page != cpu_buffer->tail_page) {
- cpu_buffer->commit_page->page->commit =
- cpu_buffer->commit_page->write;
+ if (RB_WARN_ON(cpu_buffer, !(--max_count)))
+ return;
+ if (RB_WARN_ON(cpu_buffer,
+ rb_is_reader_page(cpu_buffer->tail_page)))
+ return;
+ local_set(&cpu_buffer->commit_page->page->commit,
+ rb_page_write(cpu_buffer->commit_page));
rb_inc_page(cpu_buffer, &cpu_buffer->commit_page);
cpu_buffer->write_stamp =
cpu_buffer->commit_page->page->time_stamp;
@@ -1076,8 +1476,12 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
}
while (rb_commit_index(cpu_buffer) !=
rb_page_write(cpu_buffer->commit_page)) {
- cpu_buffer->commit_page->page->commit =
- cpu_buffer->commit_page->write;
+
+ local_set(&cpu_buffer->commit_page->page->commit,
+ rb_page_write(cpu_buffer->commit_page));
+ RB_WARN_ON(cpu_buffer,
+ local_read(&cpu_buffer->commit_page->page->commit) &
+ ~RB_WRITE_MASK);
barrier();
}
@@ -1110,7 +1514,7 @@ static void rb_inc_iter(struct ring_buffer_iter *iter)
* to the head page instead of next.
*/
if (iter->head_page == cpu_buffer->reader_page)
- iter->head_page = cpu_buffer->head_page;
+ iter->head_page = rb_set_head_page(cpu_buffer);
else
rb_inc_page(cpu_buffer, &iter->head_page);
@@ -1154,6 +1558,163 @@ rb_update_event(struct ring_buffer_event *event,
}
}
+/*
+ * rb_handle_head_page - writer hit the head page
+ *
+ * Returns: +1 to retry page
+ * 0 to continue
+ * -1 on error
+ */
+static int
+rb_handle_head_page(struct ring_buffer_per_cpu *cpu_buffer,
+ struct buffer_page *tail_page,
+ struct buffer_page *next_page)
+{
+ struct buffer_page *new_head;
+ int entries;
+ int type;
+ int ret;
+
+ entries = rb_page_entries(next_page);
+
+ /*
+ * The hard part is here. We need to move the head
+ * forward, and protect against both readers on
+ * other CPUs and writers coming in via interrupts.
+ */
+ type = rb_head_page_set_update(cpu_buffer, next_page, tail_page,
+ RB_PAGE_HEAD);
+
+ /*
+ * type can be one of four:
+ * NORMAL - an interrupt already moved it for us
+ * HEAD - we are the first to get here.
+ * UPDATE - we are the interrupt interrupting
+ * a current move.
+ * MOVED - a reader on another CPU moved the next
+ * pointer to its reader page. Give up
+ * and try again.
+ */
+
+ switch (type) {
+ case RB_PAGE_HEAD:
+ /*
+ * We changed the head to UPDATE, thus
+ * it is our responsibility to update
+ * the counters.
+ */
+ local_add(entries, &cpu_buffer->overrun);
+
+ /*
+ * The entries will be zeroed out when we move the
+ * tail page.
+ */
+
+ /* still more to do */
+ break;
+
+ case RB_PAGE_UPDATE:
+ /*
+ * This is an interrupt that interrupt the
+ * previous update. Still more to do.
+ */
+ break;
+ case RB_PAGE_NORMAL:
+ /*
+ * An interrupt came in before the update
+ * and processed this for us.
+ * Nothing left to do.
+ */
+ return 1;
+ case RB_PAGE_MOVED:
+ /*
+ * The reader is on another CPU and just did
+ * a swap with our next_page.
+ * Try again.
+ */
+ return 1;
+ default:
+ RB_WARN_ON(cpu_buffer, 1); /* WTF??? */
+ return -1;
+ }
+
+ /*
+ * Now that we are here, the old head pointer is
+ * set to UPDATE. This will keep the reader from
+ * swapping the head page with the reader page.
+ * The reader (on another CPU) will spin till
+ * we are finished.
+ *
+ * We just need to protect against interrupts
+ * doing the job. We will set the next pointer
+ * to HEAD. After that, we set the old pointer
+ * to NORMAL, but only if it was HEAD before.
+ * otherwise we are an interrupt, and only
+ * want the outer most commit to reset it.
+ */
+ new_head = next_page;
+ rb_inc_page(cpu_buffer, &new_head);
+
+ ret = rb_head_page_set_head(cpu_buffer, new_head, next_page,
+ RB_PAGE_NORMAL);
+
+ /*
+ * Valid returns are:
+ * HEAD - an interrupt came in and already set it.
+ * NORMAL - One of two things:
+ * 1) We really set it.
+ * 2) A bunch of interrupts came in and moved
+ * the page forward again.
+ */
+ switch (ret) {
+ case RB_PAGE_HEAD:
+ case RB_PAGE_NORMAL:
+ /* OK */
+ break;
+ default:
+ RB_WARN_ON(cpu_buffer, 1);
+ return -1;
+ }
+
+ /*
+ * It is possible that an interrupt came in,
+ * set the head up, then more interrupts came in
+ * and moved it again. When we get back here,
+ * the page would have been set to NORMAL but we
+ * just set it back to HEAD.
+ *
+ * How do you detect this? Well, if that happened
+ * the tail page would have moved.
+ */
+ if (ret == RB_PAGE_NORMAL) {
+ /*
+ * If the tail had moved passed next, then we need
+ * to reset the pointer.
+ */
+ if (cpu_buffer->tail_page != tail_page &&
+ cpu_buffer->tail_page != next_page)
+ rb_head_page_set_normal(cpu_buffer, new_head,
+ next_page,
+ RB_PAGE_HEAD);
+ }
+
+ /*
+ * If this was the outer most commit (the one that
+ * changed the original pointer from HEAD to UPDATE),
+ * then it is up to us to reset it to NORMAL.
+ */
+ if (type == RB_PAGE_HEAD) {
+ ret = rb_head_page_set_normal(cpu_buffer, next_page,
+ tail_page,
+ RB_PAGE_UPDATE);
+ if (RB_WARN_ON(cpu_buffer,
+ ret != RB_PAGE_UPDATE))
+ return -1;
+ }
+
+ return 0;
+}
+
static unsigned rb_calculate_event_length(unsigned length)
{
struct ring_buffer_event event; /* Used only for sizeof array */
@@ -1171,6 +1732,57 @@ static unsigned rb_calculate_event_length(unsigned length)
return length;
}
+static inline void
+rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer,
+ struct buffer_page *tail_page,
+ unsigned long tail, unsigned long length)
+{
+ struct ring_buffer_event *event;
+
+ /*
+ * Only the event that crossed the page boundary
+ * must fill the old tail_page with padding.
+ */
+ if (tail >= BUF_PAGE_SIZE) {
+ local_sub(length, &tail_page->write);
+ return;
+ }
+
+ event = __rb_page_index(tail_page, tail);
+ kmemcheck_annotate_bitfield(event, bitfield);
+
+ /*
+ * If this event is bigger than the minimum size, then
+ * we need to be careful that we don't subtract the
+ * write counter enough to allow another writer to slip
+ * in on this page.
+ * We put in a discarded commit instead, to make sure
+ * that this space is not used again.
+ *
+ * If we are less than the minimum size, we don't need to
+ * worry about it.
+ */
+ if (tail > (BUF_PAGE_SIZE - RB_EVNT_MIN_SIZE)) {
+ /* No room for any events */
+
+ /* Mark the rest of the page with padding */
+ rb_event_set_padding(event);
+
+ /* Set the write back to the previous setting */
+ local_sub(length, &tail_page->write);
+ return;
+ }
+
+ /* Put in a discarded event */
+ event->array[0] = (BUF_PAGE_SIZE - tail) - RB_EVNT_HDR_SIZE;
+ event->type_len = RINGBUF_TYPE_PADDING;
+ /* time delta must be non zero */
+ event->time_delta = 1;
+
+ /* Set write to end of buffer */
+ length = (tail + length) - BUF_PAGE_SIZE;
+ local_sub(length, &tail_page->write);
+}
static struct ring_buffer_event *
rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,
@@ -1178,128 +1790,101 @@ rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,
struct buffer_page *commit_page,
struct buffer_page *tail_page, u64 *ts)
{
- struct buffer_page *next_page, *head_page, *reader_page;
struct ring_buffer *buffer = cpu_buffer->buffer;
- struct ring_buffer_event *event;
- bool lock_taken = false;
- unsigned long flags;
+ struct buffer_page *next_page;
+ int ret;
next_page = tail_page;
- local_irq_save(flags);
- /*
- * Since the write to the buffer is still not
- * fully lockless, we must be careful with NMIs.
- * The locks in the writers are taken when a write
- * crosses to a new page. The locks protect against
- * races with the readers (this will soon be fixed
- * with a lockless solution).
- *
- * Because we can not protect against NMIs, and we
- * want to keep traces reentrant, we need to manage
- * what happens when we are in an NMI.
- *
- * NMIs can happen after we take the lock.
- * If we are in an NMI, only take the lock
- * if it is not already taken. Otherwise
- * simply fail.
- */
- if (unlikely(in_nmi())) {
- if (!__raw_spin_trylock(&cpu_buffer->lock)) {
- cpu_buffer->nmi_dropped++;
- goto out_reset;
- }
- } else
- __raw_spin_lock(&cpu_buffer->lock);
-
- lock_taken = true;
-
rb_inc_page(cpu_buffer, &next_page);
- head_page = cpu_buffer->head_page;
- reader_page = cpu_buffer->reader_page;
-
- /* we grabbed the lock before incrementing */
- if (RB_WARN_ON(cpu_buffer, next_page == reader_page))
- goto out_reset;
-
/*
* If for some reason, we had an interrupt storm that made
* it all the way around the buffer, bail, and warn
* about it.
*/
if (unlikely(next_page == commit_page)) {
- cpu_buffer->commit_overrun++;
+ local_inc(&cpu_buffer->commit_overrun);
goto out_reset;
}
- if (next_page == head_page) {
- if (!(buffer->flags & RB_FL_OVERWRITE))
- goto out_reset;
-
- /* tail_page has not moved yet? */
- if (tail_page == cpu_buffer->tail_page) {
- /* count overflows */
- cpu_buffer->overrun +=
- local_read(&head_page->entries);
-
- rb_inc_page(cpu_buffer, &head_page);
- cpu_buffer->head_page = head_page;
- cpu_buffer->head_page->read = 0;
- }
- }
-
/*
- * If the tail page is still the same as what we think
- * it is, then it is up to us to update the tail
- * pointer.
+ * This is where the fun begins!
+ *
+ * We are fighting against races between a reader that
+ * could be on another CPU trying to swap its reader
+ * page with the buffer head.
+ *
+ * We are also fighting against interrupts coming in and
+ * moving the head or tail on us as well.
+ *
+ * If the next page is the head page then we have filled
+ * the buffer, unless the commit page is still on the
+ * reader page.
*/
- if (tail_page == cpu_buffer->tail_page) {
- local_set(&next_page->write, 0);
- local_set(&next_page->entries, 0);
- local_set(&next_page->page->commit, 0);
- cpu_buffer->tail_page = next_page;
+ if (rb_is_head_page(cpu_buffer, next_page, &tail_page->list)) {
- /* reread the time stamp */
- *ts = rb_time_stamp(buffer, cpu_buffer->cpu);
- cpu_buffer->tail_page->page->time_stamp = *ts;
+ /*
+ * If the commit is not on the reader page, then
+ * move the header page.
+ */
+ if (!rb_is_reader_page(cpu_buffer->commit_page)) {
+ /*
+ * If we are not in overwrite mode,
+ * this is easy, just stop here.
+ */
+ if (!(buffer->flags & RB_FL_OVERWRITE))
+ goto out_reset;
+
+ ret = rb_handle_head_page(cpu_buffer,
+ tail_page,
+ next_page);
+ if (ret < 0)
+ goto out_reset;
+ if (ret)
+ goto out_again;
+ } else {
+ /*
+ * We need to be careful here too. The
+ * commit page could still be on the reader
+ * page. We could have a small buffer, and
+ * have filled up the buffer with events
+ * from interrupts and such, and wrapped.
+ *
+ * Note, if the tail page is also the on the
+ * reader_page, we let it move out.
+ */
+ if (unlikely((cpu_buffer->commit_page !=
+ cpu_buffer->tail_page) &&
+ (cpu_buffer->commit_page ==
+ cpu_buffer->reader_page))) {
+ local_inc(&cpu_buffer->commit_overrun);
+ goto out_reset;
+ }
+ }
}
- /*
- * The actual tail page has moved forward.
- */
- if (tail < BUF_PAGE_SIZE) {
- /* Mark the rest of the page with padding */
- event = __rb_page_index(tail_page, tail);
- kmemcheck_annotate_bitfield(event, bitfield);
- rb_event_set_padding(event);
+ ret = rb_tail_page_update(cpu_buffer, tail_page, next_page);
+ if (ret) {
+ /*
+ * Nested commits always have zero deltas, so
+ * just reread the time stamp
+ */
+ *ts = rb_time_stamp(buffer, cpu_buffer->cpu);
+ next_page->page->time_stamp = *ts;
}
- /* Set the write back to the previous setting */
- local_sub(length, &tail_page->write);
+ out_again:
- /*
- * If this was a commit entry that failed,
- * increment that too
- */
- if (tail_page == cpu_buffer->commit_page &&
- tail == rb_commit_index(cpu_buffer)) {
- rb_set_commit_to_write(cpu_buffer);
- }
-
- __raw_spin_unlock(&cpu_buffer->lock);
- local_irq_restore(flags);
+ rb_reset_tail(cpu_buffer, tail_page, tail, length);
/* fail and let the caller try again */
return ERR_PTR(-EAGAIN);
out_reset:
/* reset write */
- local_sub(length, &tail_page->write);
+ rb_reset_tail(cpu_buffer, tail_page, tail, length);
- if (likely(lock_taken))
- __raw_spin_unlock(&cpu_buffer->lock);
- local_irq_restore(flags);
return NULL;
}
@@ -1316,6 +1901,9 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
barrier();
tail_page = cpu_buffer->tail_page;
write = local_add_return(length, &tail_page->write);
+
+ /* set write to only the index of the write */
+ write &= RB_WRITE_MASK;
tail = write - length;
/* See if we shot pass the end of this buffer page */
@@ -1325,9 +1913,6 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
/* We reserved something on the buffer */
- if (RB_WARN_ON(cpu_buffer, write > BUF_PAGE_SIZE))
- return NULL;
-
event = __rb_page_index(tail_page, tail);
kmemcheck_annotate_bitfield(event, bitfield);
rb_update_event(event, type, length);
@@ -1337,11 +1922,11 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
local_inc(&tail_page->entries);
/*
- * If this is a commit and the tail is zero, then update
- * this page's time stamp.
+ * If this is the first commit on the page, then update
+ * its timestamp.
*/
- if (!tail && rb_is_commit(cpu_buffer, event))
- cpu_buffer->commit_page->page->time_stamp = *ts;
+ if (!tail)
+ tail_page->page->time_stamp = *ts;
return event;
}
@@ -1363,12 +1948,16 @@ rb_try_to_discard(struct ring_buffer_per_cpu *cpu_buffer,
bpage = cpu_buffer->tail_page;
if (bpage->page == (void *)addr && rb_page_write(bpage) == old_index) {
+ unsigned long write_mask =
+ local_read(&bpage->write) & ~RB_WRITE_MASK;
/*
* This is on the tail page. It is possible that
* a write could come in and move the tail page
* and write to the next page. That is fine
* because we just shorten what is on this page.
*/
+ old_index += write_mask;
+ new_index += write_mask;
index = local_cmpxchg(&bpage->write, old_index, new_index);
if (index == old_index)
return 1;
@@ -1410,16 +1999,16 @@ rb_add_time_stamp(struct ring_buffer_per_cpu *cpu_buffer,
return -EAGAIN;
/* Only a commited time event can update the write stamp */
- if (rb_is_commit(cpu_buffer, event)) {
+ if (rb_event_is_commit(cpu_buffer, event)) {
/*
- * If this is the first on the page, then we need to
- * update the page itself, and just put in a zero.
+ * If this is the first on the page, then it was
+ * updated with the page itself. Try to discard it
+ * and if we can't just make it zero.
*/
if (rb_event_index(event)) {
event->time_delta = *delta & TS_MASK;
event->array[0] = *delta >> TS_SHIFT;
} else {
- cpu_buffer->commit_page->page->time_stamp = *ts;
/* try to discard, since we do not need this */
if (!rb_try_to_discard(cpu_buffer, event)) {
/* nope, just zero it */
@@ -1445,8 +2034,47 @@ rb_add_time_stamp(struct ring_buffer_per_cpu *cpu_buffer,
return ret;
}
+static void rb_start_commit(struct ring_buffer_per_cpu *cpu_buffer)
+{
+ local_inc(&cpu_buffer->committing);
+ local_inc(&cpu_buffer->commits);
+}
+
+static void rb_end_commit(struct ring_buffer_per_cpu *cpu_buffer)
+{
+ unsigned long commits;
+
+ if (RB_WARN_ON(cpu_buffer,
+ !local_read(&cpu_buffer->committing)))
+ return;
+
+ again:
+ commits = local_read(&cpu_buffer->commits);
+ /* synchronize with interrupts */
+ barrier();
+ if (local_read(&cpu_buffer->committing) == 1)
+ rb_set_commit_to_write(cpu_buffer);
+
+ local_dec(&cpu_buffer->committing);
+
+ /* synchronize with interrupts */
+ barrier();
+
+ /*
+ * Need to account for interrupts coming in between the
+ * updating of the commit page and the clearing of the
+ * committing counter.
+ */
+ if (unlikely(local_read(&cpu_buffer->commits) != commits) &&
+ !local_read(&cpu_buffer->committing)) {
+ local_inc(&cpu_buffer->committing);
+ goto again;
+ }
+}
+
static struct ring_buffer_event *
-rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
+rb_reserve_next_event(struct ring_buffer *buffer,
+ struct ring_buffer_per_cpu *cpu_buffer,
unsigned long length)
{
struct ring_buffer_event *event;
@@ -1454,6 +2082,23 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
int commit = 0;
int nr_loops = 0;
+ rb_start_commit(cpu_buffer);
+
+#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP
+ /*
+ * Due to the ability to swap a cpu buffer from a buffer
+ * it is possible it was swapped before we committed.
+ * (committing stops a swap). We check for it here and
+ * if it happened, we have to fail the write.
+ */
+ barrier();
+ if (unlikely(ACCESS_ONCE(cpu_buffer->buffer) != buffer)) {
+ local_dec(&cpu_buffer->committing);
+ local_dec(&cpu_buffer->commits);
+ return NULL;
+ }
+#endif
+
length = rb_calculate_event_length(length);
again:
/*
@@ -1466,7 +2111,7 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
* Bail!
*/
if (RB_WARN_ON(cpu_buffer, ++nr_loops > 1000))
- return NULL;
+ goto out_fail;
ts = rb_time_stamp(cpu_buffer->buffer, cpu_buffer->cpu);
@@ -1497,7 +2142,7 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
commit = rb_add_time_stamp(cpu_buffer, &ts, &delta);
if (commit == -EBUSY)
- return NULL;
+ goto out_fail;
if (commit == -EAGAIN)
goto again;
@@ -1511,30 +2156,23 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
if (unlikely(PTR_ERR(event) == -EAGAIN))
goto again;
- if (!event) {
- if (unlikely(commit))
- /*
- * Ouch! We needed a timestamp and it was commited. But
- * we didn't get our event reserved.
- */
- rb_set_commit_to_write(cpu_buffer);
- return NULL;
- }
+ if (!event)
+ goto out_fail;
- /*
- * If the timestamp was commited, make the commit our entry
- * now so that we will update it when needed.
- */
- if (unlikely(commit))
- rb_set_commit_event(cpu_buffer, event);
- else if (!rb_is_commit(cpu_buffer, event))
+ if (!rb_event_is_commit(cpu_buffer, event))
delta = 0;
event->time_delta = delta;
return event;
+
+ out_fail:
+ rb_end_commit(cpu_buffer);
+ return NULL;
}
+#ifdef CONFIG_TRACING
+
#define TRACE_RECURSIVE_DEPTH 16
static int trace_recursive_lock(void)
@@ -1565,6 +2203,13 @@ static void trace_recursive_unlock(void)
current->trace_recursion--;
}
+#else
+
+#define trace_recursive_lock() (0)
+#define trace_recursive_unlock() do { } while (0)
+
+#endif
+
static DEFINE_PER_CPU(int, rb_need_resched);
/**
@@ -1614,7 +2259,7 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, unsigned long length)
if (length > BUF_MAX_DATA_SIZE)
goto out;
- event = rb_reserve_next_event(cpu_buffer, length);
+ event = rb_reserve_next_event(buffer, cpu_buffer, length);
if (!event)
goto out;
@@ -1637,18 +2282,24 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, unsigned long length)
}
EXPORT_SYMBOL_GPL(ring_buffer_lock_reserve);
+static void
+rb_update_write_stamp(struct ring_buffer_per_cpu *cpu_buffer,
+ struct ring_buffer_event *event)
+{
+ /*
+ * The event first in the commit queue updates the
+ * time stamp.
+ */
+ if (rb_event_is_commit(cpu_buffer, event))
+ cpu_buffer->write_stamp += event->time_delta;
+}
+
static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer,
struct ring_buffer_event *event)
{
local_inc(&cpu_buffer->entries);
-
- /* Only process further if we own the commit */
- if (!rb_is_commit(cpu_buffer, event))
- return;
-
- cpu_buffer->write_stamp += event->time_delta;
-
- rb_set_commit_to_write(cpu_buffer);
+ rb_update_write_stamp(cpu_buffer, event);
+ rb_end_commit(cpu_buffer);
}
/**
@@ -1694,32 +2345,57 @@ static inline void rb_event_discard(struct ring_buffer_event *event)
event->time_delta = 1;
}
-/**
- * ring_buffer_event_discard - discard any event in the ring buffer
- * @event: the event to discard
- *
- * Sometimes a event that is in the ring buffer needs to be ignored.
- * This function lets the user discard an event in the ring buffer
- * and then that event will not be read later.
- *
- * Note, it is up to the user to be careful with this, and protect
- * against races. If the user discards an event that has been consumed
- * it is possible that it could corrupt the ring buffer.
+/*
+ * Decrement the entries to the page that an event is on.
+ * The event does not even need to exist, only the pointer
+ * to the page it is on. This may only be called before the commit
+ * takes place.
*/
-void ring_buffer_event_discard(struct ring_buffer_event *event)
+static inline void
+rb_decrement_entry(struct ring_buffer_per_cpu *cpu_buffer,
+ struct ring_buffer_event *event)
{
- rb_event_discard(event);
+ unsigned long addr = (unsigned long)event;
+ struct buffer_page *bpage = cpu_buffer->commit_page;
+ struct buffer_page *start;
+
+ addr &= PAGE_MASK;
+
+ /* Do the likely case first */
+ if (likely(bpage->page == (void *)addr)) {
+ local_dec(&bpage->entries);
+ return;
+ }
+
+ /*
+ * Because the commit page may be on the reader page we
+ * start with the next page and check the end loop there.
+ */
+ rb_inc_page(cpu_buffer, &bpage);
+ start = bpage;
+ do {
+ if (bpage->page == (void *)addr) {
+ local_dec(&bpage->entries);
+ return;
+ }
+ rb_inc_page(cpu_buffer, &bpage);
+ } while (bpage != start);
+
+ /* commit not part of this buffer?? */
+ RB_WARN_ON(cpu_buffer, 1);
}
-EXPORT_SYMBOL_GPL(ring_buffer_event_discard);
/**
* ring_buffer_commit_discard - discard an event that has not been committed
* @buffer: the ring buffer
* @event: non committed event to discard
*
- * This is similar to ring_buffer_event_discard but must only be
- * performed on an event that has not been committed yet. The difference
- * is that this will also try to free the event from the ring buffer
+ * Sometimes an event that is in the ring buffer needs to be ignored.
+ * This function lets the user discard an event in the ring buffer
+ * and then that event will not be read later.
+ *
+ * This function only works if it is called before the the item has been
+ * committed. It will try to free the event from the ring buffer
* if another event has not been added behind it.
*
* If another event has been added behind it, it will set the event
@@ -1737,32 +2413,27 @@ void ring_buffer_discard_commit(struct ring_buffer *buffer,
/* The event is discarded regardless */
rb_event_discard(event);
+ cpu = smp_processor_id();
+ cpu_buffer = buffer->buffers[cpu];
+
/*
* This must only be called if the event has not been
* committed yet. Thus we can assume that preemption
* is still disabled.
*/
- RB_WARN_ON(buffer, preemptible());
+ RB_WARN_ON(buffer, !local_read(&cpu_buffer->committing));
- cpu = smp_processor_id();
- cpu_buffer = buffer->buffers[cpu];
-
- if (!rb_try_to_discard(cpu_buffer, event))
+ rb_decrement_entry(cpu_buffer, event);
+ if (rb_try_to_discard(cpu_buffer, event))
goto out;
/*
* The commit is still visible by the reader, so we
- * must increment entries.
+ * must still update the timestamp.
*/
- local_inc(&cpu_buffer->entries);
+ rb_update_write_stamp(cpu_buffer, event);
out:
- /*
- * If a write came in and pushed the tail page
- * we still need to update the commit pointer
- * if we were the commit.
- */
- if (rb_is_commit(cpu_buffer, event))
- rb_set_commit_to_write(cpu_buffer);
+ rb_end_commit(cpu_buffer);
trace_recursive_unlock();
@@ -1821,7 +2492,7 @@ int ring_buffer_write(struct ring_buffer *buffer,
if (length > BUF_MAX_DATA_SIZE)
goto out;
- event = rb_reserve_next_event(cpu_buffer, length);
+ event = rb_reserve_next_event(buffer, cpu_buffer, length);
if (!event)
goto out;
@@ -1842,9 +2513,13 @@ EXPORT_SYMBOL_GPL(ring_buffer_write);
static int rb_per_cpu_empty(struct ring_buffer_per_cpu *cpu_buffer)
{
struct buffer_page *reader = cpu_buffer->reader_page;
- struct buffer_page *head = cpu_buffer->head_page;
+ struct buffer_page *head = rb_set_head_page(cpu_buffer);
struct buffer_page *commit = cpu_buffer->commit_page;
+ /* In case of error, head will be NULL */
+ if (unlikely(!head))
+ return 1;
+
return reader->read == rb_page_commit(reader) &&
(commit == reader ||
(commit == head &&
@@ -1935,7 +2610,7 @@ unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu)
return 0;
cpu_buffer = buffer->buffers[cpu];
- ret = (local_read(&cpu_buffer->entries) - cpu_buffer->overrun)
+ ret = (local_read(&cpu_buffer->entries) - local_read(&cpu_buffer->overrun))
- cpu_buffer->read;
return ret;
@@ -1956,33 +2631,13 @@ unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu)
return 0;
cpu_buffer = buffer->buffers[cpu];
- ret = cpu_buffer->overrun;
+ ret = local_read(&cpu_buffer->overrun);
return ret;
}
EXPORT_SYMBOL_GPL(ring_buffer_overrun_cpu);
/**
- * ring_buffer_nmi_dropped_cpu - get the number of nmis that were dropped
- * @buffer: The ring buffer
- * @cpu: The per CPU buffer to get the number of overruns from
- */
-unsigned long ring_buffer_nmi_dropped_cpu(struct ring_buffer *buffer, int cpu)
-{
- struct ring_buffer_per_cpu *cpu_buffer;
- unsigned long ret;
-
- if (!cpumask_test_cpu(cpu, buffer->cpumask))
- return 0;
-
- cpu_buffer = buffer->buffers[cpu];
- ret = cpu_buffer->nmi_dropped;
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(ring_buffer_nmi_dropped_cpu);
-
-/**
* ring_buffer_commit_overrun_cpu - get the number of overruns caused by commits
* @buffer: The ring buffer
* @cpu: The per CPU buffer to get the number of overruns from
@@ -1997,7 +2652,7 @@ ring_buffer_commit_overrun_cpu(struct ring_buffer *buffer, int cpu)
return 0;
cpu_buffer = buffer->buffers[cpu];
- ret = cpu_buffer->commit_overrun;
+ ret = local_read(&cpu_buffer->commit_overrun);
return ret;
}
@@ -2020,7 +2675,7 @@ unsigned long ring_buffer_entries(struct ring_buffer *buffer)
for_each_buffer_cpu(buffer, cpu) {
cpu_buffer = buffer->buffers[cpu];
entries += (local_read(&cpu_buffer->entries) -
- cpu_buffer->overrun) - cpu_buffer->read;
+ local_read(&cpu_buffer->overrun)) - cpu_buffer->read;
}
return entries;
@@ -2043,7 +2698,7 @@ unsigned long ring_buffer_overruns(struct ring_buffer *buffer)
/* if you care about this being correct, lock the buffer */
for_each_buffer_cpu(buffer, cpu) {
cpu_buffer = buffer->buffers[cpu];
- overruns += cpu_buffer->overrun;
+ overruns += local_read(&cpu_buffer->overrun);
}
return overruns;
@@ -2056,8 +2711,10 @@ static void rb_iter_reset(struct ring_buffer_iter *iter)
/* Iterator usage is expected to have record disabled */
if (list_empty(&cpu_buffer->reader_page->list)) {
- iter->head_page = cpu_buffer->head_page;
- iter->head = cpu_buffer->head_page->read;
+ iter->head_page = rb_set_head_page(cpu_buffer);
+ if (unlikely(!iter->head_page))
+ return;
+ iter->head = iter->head_page->read;
} else {
iter->head_page = cpu_buffer->reader_page;
iter->head = cpu_buffer->reader_page->read;
@@ -2174,6 +2831,7 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
struct buffer_page *reader = NULL;
unsigned long flags;
int nr_loops = 0;
+ int ret;
local_irq_save(flags);
__raw_spin_lock(&cpu_buffer->lock);
@@ -2207,30 +2865,56 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
goto out;
/*
- * Splice the empty reader page into the list around the head.
* Reset the reader page to size zero.
*/
+ local_set(&cpu_buffer->reader_page->write, 0);
+ local_set(&cpu_buffer->reader_page->entries, 0);
+ local_set(&cpu_buffer->reader_page->page->commit, 0);
- reader = cpu_buffer->head_page;
+ spin:
+ /*
+ * Splice the empty reader page into the list around the head.
+ */
+ reader = rb_set_head_page(cpu_buffer);
cpu_buffer->reader_page->list.next = reader->list.next;
cpu_buffer->reader_page->list.prev = reader->list.prev;
- local_set(&cpu_buffer->reader_page->write, 0);
- local_set(&cpu_buffer->reader_page->entries, 0);
- local_set(&cpu_buffer->reader_page->page->commit, 0);
+ /*
+ * cpu_buffer->pages just needs to point to the buffer, it
+ * has no specific buffer page to point to. Lets move it out
+ * of our way so we don't accidently swap it.
+ */
+ cpu_buffer->pages = reader->list.prev;
- /* Make the reader page now replace the head */
- reader->list.prev->next = &cpu_buffer->reader_page->list;
- reader->list.next->prev = &cpu_buffer->reader_page->list;
+ /* The reader page will be pointing to the new head */
+ rb_set_list_to_head(cpu_buffer, &cpu_buffer->reader_page->list);
+
+ /*
+ * Here's the tricky part.
+ *
+ * We need to move the pointer past the header page.
+ * But we can only do that if a writer is not currently
+ * moving it. The page before the header page has the
+ * flag bit '1' set if it is pointing to the page we want.
+ * but if the writer is in the process of moving it
+ * than it will be '2' or already moved '0'.
+ */
+
+ ret = rb_head_page_replace(reader, cpu_buffer->reader_page);
/*
- * If the tail is on the reader, then we must set the head
- * to the inserted page, otherwise we set it one before.
+ * If we did not convert it, then we must try again.
*/
- cpu_buffer->head_page = cpu_buffer->reader_page;
+ if (!ret)
+ goto spin;
- if (cpu_buffer->commit_page != reader)
- rb_inc_page(cpu_buffer, &cpu_buffer->head_page);
+ /*
+ * Yeah! We succeeded in replacing the page.
+ *
+ * Now make the new head point back to the reader page.
+ */
+ reader->list.next->prev = &cpu_buffer->reader_page->list;
+ rb_inc_page(cpu_buffer, &cpu_buffer->head_page);
/* Finally update the reader page to the new head */
cpu_buffer->reader_page = reader;
@@ -2259,8 +2943,7 @@ static void rb_advance_reader(struct ring_buffer_per_cpu *cpu_buffer)
event = rb_reader_event(cpu_buffer);
- if (event->type_len <= RINGBUF_TYPE_DATA_TYPE_LEN_MAX
- || rb_discarded_event(event))
+ if (event->type_len <= RINGBUF_TYPE_DATA_TYPE_LEN_MAX)
cpu_buffer->read++;
rb_update_read_stamp(cpu_buffer, event);
@@ -2351,7 +3034,6 @@ rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
* the box. Return the padding, and we will release
* the current locks, and try again.
*/
- rb_advance_reader(cpu_buffer);
return event;
case RINGBUF_TYPE_TIME_EXTEND:
@@ -2446,6 +3128,21 @@ rb_iter_peek(struct ring_buffer_iter *iter, u64 *ts)
}
EXPORT_SYMBOL_GPL(ring_buffer_iter_peek);
+static inline int rb_ok_to_lock(void)
+{
+ /*
+ * If an NMI die dumps out the content of the ring buffer
+ * do not grab locks. We also permanently disable the ring
+ * buffer too. A one time deal is all you get from reading
+ * the ring buffer from an NMI.
+ */
+ if (likely(!in_nmi()))
+ return 1;
+
+ tracing_off_permanent();
+ return 0;
+}
+
/**
* ring_buffer_peek - peek at the next event to be read
* @buffer: The ring buffer to read
@@ -2461,19 +3158,25 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
struct ring_buffer_per_cpu *cpu_buffer = buffer->buffers[cpu];
struct ring_buffer_event *event;
unsigned long flags;
+ int dolock;
if (!cpumask_test_cpu(cpu, buffer->cpumask))
return NULL;
+ dolock = rb_ok_to_lock();
again:
- spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ local_irq_save(flags);
+ if (dolock)
+ spin_lock(&cpu_buffer->reader_lock);
event = rb_buffer_peek(buffer, cpu, ts);
- spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+ if (event && event->type_len == RINGBUF_TYPE_PADDING)
+ rb_advance_reader(cpu_buffer);
+ if (dolock)
+ spin_unlock(&cpu_buffer->reader_lock);
+ local_irq_restore(flags);
- if (event && event->type_len == RINGBUF_TYPE_PADDING) {
- cpu_relax();
+ if (event && event->type_len == RINGBUF_TYPE_PADDING)
goto again;
- }
return event;
}
@@ -2498,10 +3201,8 @@ ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts)
event = rb_iter_peek(iter, ts);
spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
- if (event && event->type_len == RINGBUF_TYPE_PADDING) {
- cpu_relax();
+ if (event && event->type_len == RINGBUF_TYPE_PADDING)
goto again;
- }
return event;
}
@@ -2520,6 +3221,9 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
struct ring_buffer_per_cpu *cpu_buffer;
struct ring_buffer_event *event = NULL;
unsigned long flags;
+ int dolock;
+
+ dolock = rb_ok_to_lock();
again:
/* might be called in atomic */
@@ -2529,24 +3233,23 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
goto out;
cpu_buffer = buffer->buffers[cpu];
- spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ local_irq_save(flags);
+ if (dolock)
+ spin_lock(&cpu_buffer->reader_lock);
event = rb_buffer_peek(buffer, cpu, ts);
- if (!event)
- goto out_unlock;
-
- rb_advance_reader(cpu_buffer);
+ if (event)
+ rb_advance_reader(cpu_buffer);
- out_unlock:
- spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+ if (dolock)
+ spin_unlock(&cpu_buffer->reader_lock);
+ local_irq_restore(flags);
out:
preempt_enable();
- if (event && event->type_len == RINGBUF_TYPE_PADDING) {
- cpu_relax();
+ if (event && event->type_len == RINGBUF_TYPE_PADDING)
goto again;
- }
return event;
}
@@ -2626,21 +3329,19 @@ ring_buffer_read(struct ring_buffer_iter *iter, u64 *ts)
struct ring_buffer_per_cpu *cpu_buffer = iter->cpu_buffer;
unsigned long flags;
- again:
spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ again:
event = rb_iter_peek(iter, ts);
if (!event)
goto out;
+ if (event->type_len == RINGBUF_TYPE_PADDING)
+ goto again;
+
rb_advance_iter(iter);
out:
spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
- if (event && event->type_len == RINGBUF_TYPE_PADDING) {
- cpu_relax();
- goto again;
- }
-
return event;
}
EXPORT_SYMBOL_GPL(ring_buffer_read);
@@ -2658,8 +3359,10 @@ EXPORT_SYMBOL_GPL(ring_buffer_size);
static void
rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer)
{
+ rb_head_page_deactivate(cpu_buffer);
+
cpu_buffer->head_page
- = list_entry(cpu_buffer->pages.next, struct buffer_page, list);
+ = list_entry(cpu_buffer->pages, struct buffer_page, list);
local_set(&cpu_buffer->head_page->write, 0);
local_set(&cpu_buffer->head_page->entries, 0);
local_set(&cpu_buffer->head_page->page->commit, 0);
@@ -2675,14 +3378,17 @@ rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer)
local_set(&cpu_buffer->reader_page->page->commit, 0);
cpu_buffer->reader_page->read = 0;
- cpu_buffer->nmi_dropped = 0;
- cpu_buffer->commit_overrun = 0;
- cpu_buffer->overrun = 0;
- cpu_buffer->read = 0;
+ local_set(&cpu_buffer->commit_overrun, 0);
+ local_set(&cpu_buffer->overrun, 0);
local_set(&cpu_buffer->entries, 0);
+ local_set(&cpu_buffer->committing, 0);
+ local_set(&cpu_buffer->commits, 0);
+ cpu_buffer->read = 0;
cpu_buffer->write_stamp = 0;
cpu_buffer->read_stamp = 0;
+
+ rb_head_page_activate(cpu_buffer);
}
/**
@@ -2702,12 +3408,16 @@ void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu)
spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ if (RB_WARN_ON(cpu_buffer, local_read(&cpu_buffer->committing)))
+ goto out;
+
__raw_spin_lock(&cpu_buffer->lock);
rb_reset_cpu(cpu_buffer);
__raw_spin_unlock(&cpu_buffer->lock);
+ out:
spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
atomic_dec(&cpu_buffer->record_disabled);
@@ -2734,12 +3444,25 @@ EXPORT_SYMBOL_GPL(ring_buffer_reset);
int ring_buffer_empty(struct ring_buffer *buffer)
{
struct ring_buffer_per_cpu *cpu_buffer;
+ unsigned long flags;
+ int dolock;
int cpu;
+ int ret;
+
+ dolock = rb_ok_to_lock();
/* yes this is racy, but if you don't like the race, lock the buffer */
for_each_buffer_cpu(buffer, cpu) {
cpu_buffer = buffer->buffers[cpu];
- if (!rb_per_cpu_empty(cpu_buffer))
+ local_irq_save(flags);
+ if (dolock)
+ spin_lock(&cpu_buffer->reader_lock);
+ ret = rb_per_cpu_empty(cpu_buffer);
+ if (dolock)
+ spin_unlock(&cpu_buffer->reader_lock);
+ local_irq_restore(flags);
+
+ if (!ret)
return 0;
}
@@ -2755,19 +3478,29 @@ EXPORT_SYMBOL_GPL(ring_buffer_empty);
int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu)
{
struct ring_buffer_per_cpu *cpu_buffer;
+ unsigned long flags;
+ int dolock;
int ret;
if (!cpumask_test_cpu(cpu, buffer->cpumask))
return 1;
+ dolock = rb_ok_to_lock();
+
cpu_buffer = buffer->buffers[cpu];
+ local_irq_save(flags);
+ if (dolock)
+ spin_lock(&cpu_buffer->reader_lock);
ret = rb_per_cpu_empty(cpu_buffer);
-
+ if (dolock)
+ spin_unlock(&cpu_buffer->reader_lock);
+ local_irq_restore(flags);
return ret;
}
EXPORT_SYMBOL_GPL(ring_buffer_empty_cpu);
+#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP
/**
* ring_buffer_swap_cpu - swap a CPU buffer between two ring buffers
* @buffer_a: One buffer to swap with
@@ -2822,20 +3555,28 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
atomic_inc(&cpu_buffer_a->record_disabled);
atomic_inc(&cpu_buffer_b->record_disabled);
+ ret = -EBUSY;
+ if (local_read(&cpu_buffer_a->committing))
+ goto out_dec;
+ if (local_read(&cpu_buffer_b->committing))
+ goto out_dec;
+
buffer_a->buffers[cpu] = cpu_buffer_b;
buffer_b->buffers[cpu] = cpu_buffer_a;
cpu_buffer_b->buffer = buffer_a;
cpu_buffer_a->buffer = buffer_b;
+ ret = 0;
+
+out_dec:
atomic_dec(&cpu_buffer_a->record_disabled);
atomic_dec(&cpu_buffer_b->record_disabled);
-
- ret = 0;
out:
return ret;
}
EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu);
+#endif /* CONFIG_RING_BUFFER_ALLOW_SWAP */
/**
* ring_buffer_alloc_read_page - allocate a page to read from buffer
@@ -3008,7 +3749,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
read = 0;
} else {
/* update the entry counter */
- cpu_buffer->read += local_read(&reader->entries);
+ cpu_buffer->read += rb_page_entries(reader);
/* swap the pages */
rb_init_page(bpage);
@@ -3029,6 +3770,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
}
EXPORT_SYMBOL_GPL(ring_buffer_read_page);
+#ifdef CONFIG_TRACING
static ssize_t
rb_simple_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
@@ -3096,6 +3838,7 @@ static __init int rb_init_debugfs(void)
}
fs_initcall(rb_init_debugfs);
+#endif
#ifdef CONFIG_HOTPLUG_CPU
static int rb_cpu_notify(struct notifier_block *self,
@@ -3108,7 +3851,7 @@ static int rb_cpu_notify(struct notifier_block *self,
switch (action) {
case CPU_UP_PREPARE:
case CPU_UP_PREPARE_FROZEN:
- if (cpu_isset(cpu, *buffer->cpumask))
+ if (cpumask_test_cpu(cpu, buffer->cpumask))
return NOTIFY_OK;
buffer->buffers[cpu] =
@@ -3119,7 +3862,7 @@ static int rb_cpu_notify(struct notifier_block *self,
return NOTIFY_OK;
}
smp_wmb();
- cpu_set(cpu, *buffer->cpumask);
+ cpumask_set_cpu(cpu, buffer->cpumask);
break;
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index 8d68e149a8b..573d3cc762c 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -102,8 +102,10 @@ static enum event_status read_page(int cpu)
event = (void *)&rpage->data[i];
switch (event->type_len) {
case RINGBUF_TYPE_PADDING:
- /* We don't expect any padding */
- KILL_TEST();
+ /* failed writes may be discarded events */
+ if (!event->time_delta)
+ KILL_TEST();
+ inc = event->array[0] + 4;
break;
case RINGBUF_TYPE_TIME_EXTEND:
inc = 8;
@@ -119,7 +121,7 @@ static enum event_status read_page(int cpu)
KILL_TEST();
break;
}
- inc = event->array[0];
+ inc = event->array[0] + 4;
break;
default:
entry = ring_buffer_event_data(event);
@@ -201,7 +203,7 @@ static void ring_buffer_producer(void)
* Hammer the buffer for 10 secs (this may
* make the system stall)
*/
- pr_info("Starting ring buffer hammer\n");
+ trace_printk("Starting ring buffer hammer\n");
do_gettimeofday(&start_tv);
do {
struct ring_buffer_event *event;
@@ -237,7 +239,7 @@ static void ring_buffer_producer(void)
#endif
} while (end_tv.tv_sec < (start_tv.tv_sec + RUN_TIME) && !kill_test);
- pr_info("End ring buffer hammer\n");
+ trace_printk("End ring buffer hammer\n");
if (consumer) {
/* Init both completions here to avoid races */
@@ -260,49 +262,50 @@ static void ring_buffer_producer(void)
overruns = ring_buffer_overruns(buffer);
if (kill_test)
- pr_info("ERROR!\n");
- pr_info("Time: %lld (usecs)\n", time);
- pr_info("Overruns: %lld\n", overruns);
+ trace_printk("ERROR!\n");
+ trace_printk("Time: %lld (usecs)\n", time);
+ trace_printk("Overruns: %lld\n", overruns);
if (disable_reader)
- pr_info("Read: (reader disabled)\n");
+ trace_printk("Read: (reader disabled)\n");
else
- pr_info("Read: %ld (by %s)\n", read,
+ trace_printk("Read: %ld (by %s)\n", read,
read_events ? "events" : "pages");
- pr_info("Entries: %lld\n", entries);
- pr_info("Total: %lld\n", entries + overruns + read);
- pr_info("Missed: %ld\n", missed);
- pr_info("Hit: %ld\n", hit);
+ trace_printk("Entries: %lld\n", entries);
+ trace_printk("Total: %lld\n", entries + overruns + read);
+ trace_printk("Missed: %ld\n", missed);
+ trace_printk("Hit: %ld\n", hit);
/* Convert time from usecs to millisecs */
do_div(time, USEC_PER_MSEC);
if (time)
hit /= (long)time;
else
- pr_info("TIME IS ZERO??\n");
+ trace_printk("TIME IS ZERO??\n");
- pr_info("Entries per millisec: %ld\n", hit);
+ trace_printk("Entries per millisec: %ld\n", hit);
if (hit) {
/* Calculate the average time in nanosecs */
avg = NSEC_PER_MSEC / hit;
- pr_info("%ld ns per entry\n", avg);
+ trace_printk("%ld ns per entry\n", avg);
}
if (missed) {
if (time)
missed /= (long)time;
- pr_info("Total iterations per millisec: %ld\n", hit + missed);
+ trace_printk("Total iterations per millisec: %ld\n",
+ hit + missed);
/* it is possible that hit + missed will overflow and be zero */
if (!(hit + missed)) {
- pr_info("hit + missed overflowed and totalled zero!\n");
+ trace_printk("hit + missed overflowed and totalled zero!\n");
hit--; /* make it non zero */
}
/* Caculate the average time in nanosecs */
avg = NSEC_PER_MSEC / (hit + missed);
- pr_info("%ld ns per entry\n", avg);
+ trace_printk("%ld ns per entry\n", avg);
}
}
@@ -353,7 +356,7 @@ static int ring_buffer_producer_thread(void *arg)
ring_buffer_producer();
- pr_info("Sleeping for 10 secs\n");
+ trace_printk("Sleeping for 10 secs\n");
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(HZ * SLEEP_TIME);
__set_current_state(TASK_RUNNING);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c1878bfb2e1..5c75deeefe3 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -17,6 +17,7 @@
#include <linux/writeback.h>
#include <linux/kallsyms.h>
#include <linux/seq_file.h>
+#include <linux/smp_lock.h>
#include <linux/notifier.h>
#include <linux/irqflags.h>
#include <linux/debugfs.h>
@@ -42,14 +43,11 @@
#define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE)
-unsigned long __read_mostly tracing_max_latency;
-unsigned long __read_mostly tracing_thresh;
-
/*
* On boot up, the ring buffer is set to the minimum size, so that
* we do not waste memory on systems that are not using tracing.
*/
-static int ring_buffer_expanded;
+int ring_buffer_expanded;
/*
* We need to change this state when a selftest is running.
@@ -63,7 +61,7 @@ static bool __read_mostly tracing_selftest_running;
/*
* If a tracer is running, we do not want to run SELFTEST.
*/
-static bool __read_mostly tracing_selftest_disabled;
+bool __read_mostly tracing_selftest_disabled;
/* For tracers that don't implement custom flags */
static struct tracer_opt dummy_tracer_opt[] = {
@@ -88,7 +86,7 @@ static int dummy_set_flag(u32 old_flags, u32 bit, int set)
*/
static int tracing_disabled = 1;
-static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled);
+DEFINE_PER_CPU(local_t, ftrace_cpu_disabled);
static inline void ftrace_disable_cpu(void)
{
@@ -171,10 +169,11 @@ static struct trace_array global_trace;
static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu);
-int filter_current_check_discard(struct ftrace_event_call *call, void *rec,
+int filter_current_check_discard(struct ring_buffer *buffer,
+ struct ftrace_event_call *call, void *rec,
struct ring_buffer_event *event)
{
- return filter_check_discard(call, rec, global_trace.buffer, event);
+ return filter_check_discard(call, rec, buffer, event);
}
EXPORT_SYMBOL_GPL(filter_current_check_discard);
@@ -265,6 +264,9 @@ unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME |
TRACE_ITER_GRAPH_TIME;
+static int trace_stop_count;
+static DEFINE_SPINLOCK(tracing_start_lock);
+
/**
* trace_wake_up - wake up tasks waiting for trace input
*
@@ -284,13 +286,12 @@ void trace_wake_up(void)
static int __init set_buf_size(char *str)
{
unsigned long buf_size;
- int ret;
if (!str)
return 0;
- ret = strict_strtoul(str, 0, &buf_size);
+ buf_size = memparse(str, &str);
/* nr_entries can not be zero */
- if (ret < 0 || buf_size == 0)
+ if (buf_size == 0)
return 0;
trace_buf_size = buf_size;
return 1;
@@ -323,50 +324,20 @@ static const char *trace_options[] = {
"printk-msg-only",
"context-info",
"latency-format",
- "global-clock",
"sleep-time",
"graph-time",
NULL
};
-/*
- * ftrace_max_lock is used to protect the swapping of buffers
- * when taking a max snapshot. The buffers themselves are
- * protected by per_cpu spinlocks. But the action of the swap
- * needs its own lock.
- *
- * This is defined as a raw_spinlock_t in order to help
- * with performance when lockdep debugging is enabled.
- */
-static raw_spinlock_t ftrace_max_lock =
- (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
-
-/*
- * Copy the new maximum trace into the separate maximum-trace
- * structure. (this way the maximum trace is permanently saved,
- * for later retrieval via /sys/kernel/debug/tracing/latency_trace)
- */
-static void
-__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
-{
- struct trace_array_cpu *data = tr->data[cpu];
-
- max_tr.cpu = cpu;
- max_tr.time_start = data->preempt_timestamp;
-
- data = max_tr.data[cpu];
- data->saved_latency = tracing_max_latency;
-
- memcpy(data->comm, tsk->comm, TASK_COMM_LEN);
- data->pid = tsk->pid;
- data->uid = task_uid(tsk);
- data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
- data->policy = tsk->policy;
- data->rt_priority = tsk->rt_priority;
+static struct {
+ u64 (*func)(void);
+ const char *name;
+} trace_clocks[] = {
+ { trace_clock_local, "local" },
+ { trace_clock_global, "global" },
+};
- /* record this tasks comm */
- tracing_record_cmdline(tsk);
-}
+int trace_clock_id;
ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
{
@@ -411,6 +382,56 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
return cnt;
}
+/*
+ * ftrace_max_lock is used to protect the swapping of buffers
+ * when taking a max snapshot. The buffers themselves are
+ * protected by per_cpu spinlocks. But the action of the swap
+ * needs its own lock.
+ *
+ * This is defined as a raw_spinlock_t in order to help
+ * with performance when lockdep debugging is enabled.
+ *
+ * It is also used in other places outside the update_max_tr
+ * so it needs to be defined outside of the
+ * CONFIG_TRACER_MAX_TRACE.
+ */
+static raw_spinlock_t ftrace_max_lock =
+ (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+unsigned long __read_mostly tracing_max_latency;
+unsigned long __read_mostly tracing_thresh;
+
+/*
+ * Copy the new maximum trace into the separate maximum-trace
+ * structure. (this way the maximum trace is permanently saved,
+ * for later retrieval via /sys/kernel/debug/tracing/latency_trace)
+ */
+static void
+__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
+{
+ struct trace_array_cpu *data = tr->data[cpu];
+ struct trace_array_cpu *max_data = tr->data[cpu];
+
+ max_tr.cpu = cpu;
+ max_tr.time_start = data->preempt_timestamp;
+
+ max_data = max_tr.data[cpu];
+ max_data->saved_latency = tracing_max_latency;
+ max_data->critical_start = data->critical_start;
+ max_data->critical_end = data->critical_end;
+
+ memcpy(data->comm, tsk->comm, TASK_COMM_LEN);
+ max_data->pid = tsk->pid;
+ max_data->uid = task_uid(tsk);
+ max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
+ max_data->policy = tsk->policy;
+ max_data->rt_priority = tsk->rt_priority;
+
+ /* record this tasks comm */
+ tracing_record_cmdline(tsk);
+}
+
/**
* update_max_tr - snapshot all trace buffers from global_trace to max_tr
* @tr: tracer
@@ -425,16 +446,15 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
struct ring_buffer *buf = tr->buffer;
+ if (trace_stop_count)
+ return;
+
WARN_ON_ONCE(!irqs_disabled());
__raw_spin_lock(&ftrace_max_lock);
tr->buffer = max_tr.buffer;
max_tr.buffer = buf;
- ftrace_disable_cpu();
- ring_buffer_reset(tr->buffer);
- ftrace_enable_cpu();
-
__update_max_tr(tr, tsk, cpu);
__raw_spin_unlock(&ftrace_max_lock);
}
@@ -452,21 +472,35 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
int ret;
+ if (trace_stop_count)
+ return;
+
WARN_ON_ONCE(!irqs_disabled());
__raw_spin_lock(&ftrace_max_lock);
ftrace_disable_cpu();
- ring_buffer_reset(max_tr.buffer);
ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu);
+ if (ret == -EBUSY) {
+ /*
+ * We failed to swap the buffer due to a commit taking
+ * place on this CPU. We fail to record, but we reset
+ * the max trace buffer (no one writes directly to it)
+ * and flag that it failed.
+ */
+ trace_array_printk(&max_tr, _THIS_IP_,
+ "Failed to swap buffers due to commit in progress\n");
+ }
+
ftrace_enable_cpu();
- WARN_ON_ONCE(ret && ret != -EAGAIN);
+ WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY);
__update_max_tr(tr, tsk, cpu);
__raw_spin_unlock(&ftrace_max_lock);
}
+#endif /* CONFIG_TRACER_MAX_TRACE */
/**
* register_tracer - register a tracer with the ftrace system.
@@ -523,7 +557,6 @@ __acquires(kernel_lock)
if (type->selftest && !tracing_selftest_disabled) {
struct tracer *saved_tracer = current_trace;
struct trace_array *tr = &global_trace;
- int i;
/*
* Run a selftest on this tracer.
@@ -532,8 +565,7 @@ __acquires(kernel_lock)
* internal tracing to verify that everything is in order.
* If we fail, we do not register this tracer.
*/
- for_each_tracing_cpu(i)
- tracing_reset(tr, i);
+ tracing_reset_online_cpus(tr);
current_trace = type;
/* the test is responsible for initializing and enabling */
@@ -546,8 +578,7 @@ __acquires(kernel_lock)
goto out;
}
/* Only reset on passing, to avoid touching corrupted buffers */
- for_each_tracing_cpu(i)
- tracing_reset(tr, i);
+ tracing_reset_online_cpus(tr);
printk(KERN_CONT "PASSED\n");
}
@@ -622,21 +653,42 @@ void unregister_tracer(struct tracer *type)
mutex_unlock(&trace_types_lock);
}
-void tracing_reset(struct trace_array *tr, int cpu)
+static void __tracing_reset(struct trace_array *tr, int cpu)
{
ftrace_disable_cpu();
ring_buffer_reset_cpu(tr->buffer, cpu);
ftrace_enable_cpu();
}
+void tracing_reset(struct trace_array *tr, int cpu)
+{
+ struct ring_buffer *buffer = tr->buffer;
+
+ ring_buffer_record_disable(buffer);
+
+ /* Make sure all commits have finished */
+ synchronize_sched();
+ __tracing_reset(tr, cpu);
+
+ ring_buffer_record_enable(buffer);
+}
+
void tracing_reset_online_cpus(struct trace_array *tr)
{
+ struct ring_buffer *buffer = tr->buffer;
int cpu;
+ ring_buffer_record_disable(buffer);
+
+ /* Make sure all commits have finished */
+ synchronize_sched();
+
tr->time_start = ftrace_now(tr->cpu);
for_each_online_cpu(cpu)
- tracing_reset(tr, cpu);
+ __tracing_reset(tr, cpu);
+
+ ring_buffer_record_enable(buffer);
}
void tracing_reset_current(int cpu)
@@ -667,9 +719,6 @@ static void trace_init_cmdlines(void)
cmdline_idx = 0;
}
-static int trace_stop_count;
-static DEFINE_SPINLOCK(tracing_start_lock);
-
/**
* ftrace_off_permanent - disable all ftrace code permanently
*
@@ -848,15 +897,17 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) |
(need_resched() ? TRACE_FLAG_NEED_RESCHED : 0);
}
+EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
-struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
- int type,
- unsigned long len,
- unsigned long flags, int pc)
+struct ring_buffer_event *
+trace_buffer_lock_reserve(struct ring_buffer *buffer,
+ int type,
+ unsigned long len,
+ unsigned long flags, int pc)
{
struct ring_buffer_event *event;
- event = ring_buffer_lock_reserve(tr->buffer, len);
+ event = ring_buffer_lock_reserve(buffer, len);
if (event != NULL) {
struct trace_entry *ent = ring_buffer_event_data(event);
@@ -866,58 +917,60 @@ struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
return event;
}
-static void ftrace_trace_stack(struct trace_array *tr,
- unsigned long flags, int skip, int pc);
-static void ftrace_trace_userstack(struct trace_array *tr,
- unsigned long flags, int pc);
-static inline void __trace_buffer_unlock_commit(struct trace_array *tr,
- struct ring_buffer_event *event,
- unsigned long flags, int pc,
- int wake)
+static inline void
+__trace_buffer_unlock_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event,
+ unsigned long flags, int pc,
+ int wake)
{
- ring_buffer_unlock_commit(tr->buffer, event);
+ ring_buffer_unlock_commit(buffer, event);
- ftrace_trace_stack(tr, flags, 6, pc);
- ftrace_trace_userstack(tr, flags, pc);
+ ftrace_trace_stack(buffer, flags, 6, pc);
+ ftrace_trace_userstack(buffer, flags, pc);
if (wake)
trace_wake_up();
}
-void trace_buffer_unlock_commit(struct trace_array *tr,
- struct ring_buffer_event *event,
- unsigned long flags, int pc)
+void trace_buffer_unlock_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event,
+ unsigned long flags, int pc)
{
- __trace_buffer_unlock_commit(tr, event, flags, pc, 1);
+ __trace_buffer_unlock_commit(buffer, event, flags, pc, 1);
}
struct ring_buffer_event *
-trace_current_buffer_lock_reserve(int type, unsigned long len,
+trace_current_buffer_lock_reserve(struct ring_buffer **current_rb,
+ int type, unsigned long len,
unsigned long flags, int pc)
{
- return trace_buffer_lock_reserve(&global_trace,
+ *current_rb = global_trace.buffer;
+ return trace_buffer_lock_reserve(*current_rb,
type, len, flags, pc);
}
EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve);
-void trace_current_buffer_unlock_commit(struct ring_buffer_event *event,
+void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event,
unsigned long flags, int pc)
{
- __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1);
+ __trace_buffer_unlock_commit(buffer, event, flags, pc, 1);
}
EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit);
-void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event,
- unsigned long flags, int pc)
+void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event,
+ unsigned long flags, int pc)
{
- __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0);
+ __trace_buffer_unlock_commit(buffer, event, flags, pc, 0);
}
EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit);
-void trace_current_buffer_discard_commit(struct ring_buffer_event *event)
+void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event)
{
- ring_buffer_discard_commit(global_trace.buffer, event);
+ ring_buffer_discard_commit(buffer, event);
}
EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit);
@@ -927,6 +980,7 @@ trace_function(struct trace_array *tr,
int pc)
{
struct ftrace_event_call *call = &event_function;
+ struct ring_buffer *buffer = tr->buffer;
struct ring_buffer_event *event;
struct ftrace_entry *entry;
@@ -934,7 +988,7 @@ trace_function(struct trace_array *tr,
if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
return;
- event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry),
+ event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry),
flags, pc);
if (!event)
return;
@@ -942,57 +996,9 @@ trace_function(struct trace_array *tr,
entry->ip = ip;
entry->parent_ip = parent_ip;
- if (!filter_check_discard(call, entry, tr->buffer, event))
- ring_buffer_unlock_commit(tr->buffer, event);
-}
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static int __trace_graph_entry(struct trace_array *tr,
- struct ftrace_graph_ent *trace,
- unsigned long flags,
- int pc)
-{
- struct ftrace_event_call *call = &event_funcgraph_entry;
- struct ring_buffer_event *event;
- struct ftrace_graph_ent_entry *entry;
-
- if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
- return 0;
-
- event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT,
- sizeof(*entry), flags, pc);
- if (!event)
- return 0;
- entry = ring_buffer_event_data(event);
- entry->graph_ent = *trace;
- if (!filter_current_check_discard(call, entry, event))
- ring_buffer_unlock_commit(global_trace.buffer, event);
-
- return 1;
-}
-
-static void __trace_graph_return(struct trace_array *tr,
- struct ftrace_graph_ret *trace,
- unsigned long flags,
- int pc)
-{
- struct ftrace_event_call *call = &event_funcgraph_exit;
- struct ring_buffer_event *event;
- struct ftrace_graph_ret_entry *entry;
-
- if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
- return;
-
- event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET,
- sizeof(*entry), flags, pc);
- if (!event)
- return;
- entry = ring_buffer_event_data(event);
- entry->ret = *trace;
- if (!filter_current_check_discard(call, entry, event))
- ring_buffer_unlock_commit(global_trace.buffer, event);
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
}
-#endif
void
ftrace(struct trace_array *tr, struct trace_array_cpu *data,
@@ -1003,17 +1009,17 @@ ftrace(struct trace_array *tr, struct trace_array_cpu *data,
trace_function(tr, ip, parent_ip, flags, pc);
}
-static void __ftrace_trace_stack(struct trace_array *tr,
+#ifdef CONFIG_STACKTRACE
+static void __ftrace_trace_stack(struct ring_buffer *buffer,
unsigned long flags,
int skip, int pc)
{
-#ifdef CONFIG_STACKTRACE
struct ftrace_event_call *call = &event_kernel_stack;
struct ring_buffer_event *event;
struct stack_entry *entry;
struct stack_trace trace;
- event = trace_buffer_lock_reserve(tr, TRACE_STACK,
+ event = trace_buffer_lock_reserve(buffer, TRACE_STACK,
sizeof(*entry), flags, pc);
if (!event)
return;
@@ -1026,32 +1032,28 @@ static void __ftrace_trace_stack(struct trace_array *tr,
trace.entries = entry->caller;
save_stack_trace(&trace);
- if (!filter_check_discard(call, entry, tr->buffer, event))
- ring_buffer_unlock_commit(tr->buffer, event);
-#endif
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
}
-static void ftrace_trace_stack(struct trace_array *tr,
- unsigned long flags,
- int skip, int pc)
+void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
+ int skip, int pc)
{
if (!(trace_flags & TRACE_ITER_STACKTRACE))
return;
- __ftrace_trace_stack(tr, flags, skip, pc);
+ __ftrace_trace_stack(buffer, flags, skip, pc);
}
-void __trace_stack(struct trace_array *tr,
- unsigned long flags,
- int skip, int pc)
+void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
+ int pc)
{
- __ftrace_trace_stack(tr, flags, skip, pc);
+ __ftrace_trace_stack(tr->buffer, flags, skip, pc);
}
-static void ftrace_trace_userstack(struct trace_array *tr,
- unsigned long flags, int pc)
+void
+ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
{
-#ifdef CONFIG_STACKTRACE
struct ftrace_event_call *call = &event_user_stack;
struct ring_buffer_event *event;
struct userstack_entry *entry;
@@ -1060,7 +1062,7 @@ static void ftrace_trace_userstack(struct trace_array *tr,
if (!(trace_flags & TRACE_ITER_USERSTACKTRACE))
return;
- event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK,
+ event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK,
sizeof(*entry), flags, pc);
if (!event)
return;
@@ -1074,9 +1076,8 @@ static void ftrace_trace_userstack(struct trace_array *tr,
trace.entries = entry->caller;
save_stack_trace_user(&trace);
- if (!filter_check_discard(call, entry, tr->buffer, event))
- ring_buffer_unlock_commit(tr->buffer, event);
-#endif
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
}
#ifdef UNUSED
@@ -1086,6 +1087,8 @@ static void __trace_userstack(struct trace_array *tr, unsigned long flags)
}
#endif /* UNUSED */
+#endif /* CONFIG_STACKTRACE */
+
static void
ftrace_trace_special(void *__tr,
unsigned long arg1, unsigned long arg2, unsigned long arg3,
@@ -1093,9 +1096,10 @@ ftrace_trace_special(void *__tr,
{
struct ring_buffer_event *event;
struct trace_array *tr = __tr;
+ struct ring_buffer *buffer = tr->buffer;
struct special_entry *entry;
- event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL,
+ event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL,
sizeof(*entry), 0, pc);
if (!event)
return;
@@ -1103,7 +1107,7 @@ ftrace_trace_special(void *__tr,
entry->arg1 = arg1;
entry->arg2 = arg2;
entry->arg3 = arg3;
- trace_buffer_unlock_commit(tr, event, 0, pc);
+ trace_buffer_unlock_commit(buffer, event, 0, pc);
}
void
@@ -1114,62 +1118,6 @@ __trace_special(void *__tr, void *__data,
}
void
-tracing_sched_switch_trace(struct trace_array *tr,
- struct task_struct *prev,
- struct task_struct *next,
- unsigned long flags, int pc)
-{
- struct ftrace_event_call *call = &event_context_switch;
- struct ring_buffer_event *event;
- struct ctx_switch_entry *entry;
-
- event = trace_buffer_lock_reserve(tr, TRACE_CTX,
- sizeof(*entry), flags, pc);
- if (!event)
- return;
- entry = ring_buffer_event_data(event);
- entry->prev_pid = prev->pid;
- entry->prev_prio = prev->prio;
- entry->prev_state = prev->state;
- entry->next_pid = next->pid;
- entry->next_prio = next->prio;
- entry->next_state = next->state;
- entry->next_cpu = task_cpu(next);
-
- if (!filter_check_discard(call, entry, tr->buffer, event))
- trace_buffer_unlock_commit(tr, event, flags, pc);
-}
-
-void
-tracing_sched_wakeup_trace(struct trace_array *tr,
- struct task_struct *wakee,
- struct task_struct *curr,
- unsigned long flags, int pc)
-{
- struct ftrace_event_call *call = &event_wakeup;
- struct ring_buffer_event *event;
- struct ctx_switch_entry *entry;
-
- event = trace_buffer_lock_reserve(tr, TRACE_WAKE,
- sizeof(*entry), flags, pc);
- if (!event)
- return;
- entry = ring_buffer_event_data(event);
- entry->prev_pid = curr->pid;
- entry->prev_prio = curr->prio;
- entry->prev_state = curr->state;
- entry->next_pid = wakee->pid;
- entry->next_prio = wakee->prio;
- entry->next_state = wakee->state;
- entry->next_cpu = task_cpu(wakee);
-
- if (!filter_check_discard(call, entry, tr->buffer, event))
- ring_buffer_unlock_commit(tr->buffer, event);
- ftrace_trace_stack(tr, flags, 6, pc);
- ftrace_trace_userstack(tr, flags, pc);
-}
-
-void
ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
{
struct trace_array *tr = &global_trace;
@@ -1193,68 +1141,6 @@ ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
local_irq_restore(flags);
}
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-int trace_graph_entry(struct ftrace_graph_ent *trace)
-{
- struct trace_array *tr = &global_trace;
- struct trace_array_cpu *data;
- unsigned long flags;
- long disabled;
- int ret;
- int cpu;
- int pc;
-
- if (!ftrace_trace_task(current))
- return 0;
-
- if (!ftrace_graph_addr(trace->func))
- return 0;
-
- local_irq_save(flags);
- cpu = raw_smp_processor_id();
- data = tr->data[cpu];
- disabled = atomic_inc_return(&data->disabled);
- if (likely(disabled == 1)) {
- pc = preempt_count();
- ret = __trace_graph_entry(tr, trace, flags, pc);
- } else {
- ret = 0;
- }
- /* Only do the atomic if it is not already set */
- if (!test_tsk_trace_graph(current))
- set_tsk_trace_graph(current);
-
- atomic_dec(&data->disabled);
- local_irq_restore(flags);
-
- return ret;
-}
-
-void trace_graph_return(struct ftrace_graph_ret *trace)
-{
- struct trace_array *tr = &global_trace;
- struct trace_array_cpu *data;
- unsigned long flags;
- long disabled;
- int cpu;
- int pc;
-
- local_irq_save(flags);
- cpu = raw_smp_processor_id();
- data = tr->data[cpu];
- disabled = atomic_inc_return(&data->disabled);
- if (likely(disabled == 1)) {
- pc = preempt_count();
- __trace_graph_return(tr, trace, flags, pc);
- }
- if (!trace->depth)
- clear_tsk_trace_graph(current);
- atomic_dec(&data->disabled);
- local_irq_restore(flags);
-}
-#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-
/**
* trace_vbprintk - write binary msg to tracing buffer
*
@@ -1267,6 +1153,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
struct ftrace_event_call *call = &event_bprint;
struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
struct trace_array *tr = &global_trace;
struct trace_array_cpu *data;
struct bprint_entry *entry;
@@ -1299,7 +1186,9 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
goto out_unlock;
size = sizeof(*entry) + sizeof(u32) * len;
- event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc);
+ buffer = tr->buffer;
+ event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size,
+ flags, pc);
if (!event)
goto out_unlock;
entry = ring_buffer_event_data(event);
@@ -1307,8 +1196,8 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
entry->fmt = fmt;
memcpy(entry->buf, trace_buf, sizeof(u32) * len);
- if (!filter_check_discard(call, entry, tr->buffer, event))
- ring_buffer_unlock_commit(tr->buffer, event);
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
out_unlock:
__raw_spin_unlock(&trace_buf_lock);
@@ -1323,14 +1212,30 @@ out:
}
EXPORT_SYMBOL_GPL(trace_vbprintk);
-int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
+int trace_array_printk(struct trace_array *tr,
+ unsigned long ip, const char *fmt, ...)
+{
+ int ret;
+ va_list ap;
+
+ if (!(trace_flags & TRACE_ITER_PRINTK))
+ return 0;
+
+ va_start(ap, fmt);
+ ret = trace_array_vprintk(tr, ip, fmt, ap);
+ va_end(ap);
+ return ret;
+}
+
+int trace_array_vprintk(struct trace_array *tr,
+ unsigned long ip, const char *fmt, va_list args)
{
static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED;
static char trace_buf[TRACE_BUF_SIZE];
struct ftrace_event_call *call = &event_print;
struct ring_buffer_event *event;
- struct trace_array *tr = &global_trace;
+ struct ring_buffer *buffer;
struct trace_array_cpu *data;
int cpu, len = 0, size, pc;
struct print_entry *entry;
@@ -1358,7 +1263,9 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
trace_buf[len] = 0;
size = sizeof(*entry) + len + 1;
- event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc);
+ buffer = tr->buffer;
+ event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
+ irq_flags, pc);
if (!event)
goto out_unlock;
entry = ring_buffer_event_data(event);
@@ -1366,8 +1273,8 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
memcpy(&entry->buf, trace_buf, len);
entry->buf[len] = 0;
- if (!filter_check_discard(call, entry, tr->buffer, event))
- ring_buffer_unlock_commit(tr->buffer, event);
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
out_unlock:
__raw_spin_unlock(&trace_buf_lock);
@@ -1379,6 +1286,11 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
return len;
}
+
+int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
+{
+ return trace_array_printk(&global_trace, ip, fmt, args);
+}
EXPORT_SYMBOL_GPL(trace_vprintk);
enum trace_file_type {
@@ -1518,6 +1430,37 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos)
return ent;
}
+static void tracing_iter_reset(struct trace_iterator *iter, int cpu)
+{
+ struct trace_array *tr = iter->tr;
+ struct ring_buffer_event *event;
+ struct ring_buffer_iter *buf_iter;
+ unsigned long entries = 0;
+ u64 ts;
+
+ tr->data[cpu]->skipped_entries = 0;
+
+ if (!iter->buffer_iter[cpu])
+ return;
+
+ buf_iter = iter->buffer_iter[cpu];
+ ring_buffer_iter_reset(buf_iter);
+
+ /*
+ * We could have the case with the max latency tracers
+ * that a reset never took place on a cpu. This is evident
+ * by the timestamp being before the start of the buffer.
+ */
+ while ((event = ring_buffer_iter_peek(buf_iter, &ts))) {
+ if (ts >= iter->tr->time_start)
+ break;
+ entries++;
+ ring_buffer_read(buf_iter, NULL);
+ }
+
+ tr->data[cpu]->skipped_entries = entries;
+}
+
/*
* No necessary locking here. The worst thing which can
* happen is loosing events consumed at the same time
@@ -1556,10 +1499,9 @@ static void *s_start(struct seq_file *m, loff_t *pos)
if (cpu_file == TRACE_PIPE_ALL_CPU) {
for_each_tracing_cpu(cpu)
- ring_buffer_iter_reset(iter->buffer_iter[cpu]);
+ tracing_iter_reset(iter, cpu);
} else
- ring_buffer_iter_reset(iter->buffer_iter[cpu_file]);
-
+ tracing_iter_reset(iter, cpu_file);
ftrace_enable_cpu();
@@ -1608,16 +1550,32 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
struct trace_array *tr = iter->tr;
struct trace_array_cpu *data = tr->data[tr->cpu];
struct tracer *type = current_trace;
- unsigned long total;
- unsigned long entries;
+ unsigned long entries = 0;
+ unsigned long total = 0;
+ unsigned long count;
const char *name = "preemption";
+ int cpu;
if (type)
name = type->name;
- entries = ring_buffer_entries(iter->tr->buffer);
- total = entries +
- ring_buffer_overruns(iter->tr->buffer);
+
+ for_each_tracing_cpu(cpu) {
+ count = ring_buffer_entries_cpu(tr->buffer, cpu);
+ /*
+ * If this buffer has skipped entries, then we hold all
+ * entries for the trace and we need to ignore the
+ * ones before the time stamp.
+ */
+ if (tr->data[cpu]->skipped_entries) {
+ count -= tr->data[cpu]->skipped_entries;
+ /* total is the same as the entries */
+ total += count;
+ } else
+ total += count +
+ ring_buffer_overrun_cpu(tr->buffer, cpu);
+ entries += count;
+ }
seq_printf(m, "# %s latency trace v1.1.5 on %s\n",
name, UTS_RELEASE);
@@ -1659,7 +1617,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
seq_puts(m, "\n# => ended at: ");
seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags);
trace_print_seq(m, &iter->seq);
- seq_puts(m, "#\n");
+ seq_puts(m, "\n#\n");
}
seq_puts(m, "#\n");
@@ -1678,6 +1636,9 @@ static void test_cpu_buff_start(struct trace_iterator *iter)
if (cpumask_test_cpu(iter->cpu, iter->started))
return;
+ if (iter->tr->data[iter->cpu]->skipped_entries)
+ return;
+
cpumask_set_cpu(iter->cpu, iter->started);
/* Don't print started cpu buffer for the first entry of the trace */
@@ -1940,19 +1901,23 @@ __tracing_open(struct inode *inode, struct file *file)
if (ring_buffer_overruns(iter->tr->buffer))
iter->iter_flags |= TRACE_FILE_ANNOTATE;
+ /* stop the trace while dumping */
+ tracing_stop();
+
if (iter->cpu_file == TRACE_PIPE_ALL_CPU) {
for_each_tracing_cpu(cpu) {
iter->buffer_iter[cpu] =
ring_buffer_read_start(iter->tr->buffer, cpu);
+ tracing_iter_reset(iter, cpu);
}
} else {
cpu = iter->cpu_file;
iter->buffer_iter[cpu] =
ring_buffer_read_start(iter->tr->buffer, cpu);
+ tracing_iter_reset(iter, cpu);
}
- /* TODO stop tracer */
ret = seq_open(file, &tracer_seq_ops);
if (ret < 0) {
fail_ret = ERR_PTR(ret);
@@ -1962,9 +1927,6 @@ __tracing_open(struct inode *inode, struct file *file)
m = file->private_data;
m->private = iter;
- /* stop the trace while dumping */
- tracing_stop();
-
mutex_unlock(&trace_types_lock);
return iter;
@@ -1975,6 +1937,7 @@ __tracing_open(struct inode *inode, struct file *file)
ring_buffer_read_finish(iter->buffer_iter[cpu]);
}
free_cpumask_var(iter->started);
+ tracing_start();
fail:
mutex_unlock(&trace_types_lock);
kfree(iter->trace);
@@ -2031,7 +1994,7 @@ static int tracing_open(struct inode *inode, struct file *file)
/* If this file was open for write, then erase contents */
if ((file->f_mode & FMODE_WRITE) &&
- !(file->f_flags & O_APPEND)) {
+ (file->f_flags & O_TRUNC)) {
long cpu = (long) inode->i_private;
if (cpu == TRACE_PIPE_ALL_CPU)
@@ -2053,25 +2016,23 @@ static int tracing_open(struct inode *inode, struct file *file)
static void *
t_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct tracer *t = m->private;
+ struct tracer *t = v;
(*pos)++;
if (t)
t = t->next;
- m->private = t;
-
return t;
}
static void *t_start(struct seq_file *m, loff_t *pos)
{
- struct tracer *t = m->private;
+ struct tracer *t;
loff_t l = 0;
mutex_lock(&trace_types_lock);
- for (; t && l < *pos; t = t_next(m, t, &l))
+ for (t = trace_types; t && l < *pos; t = t_next(m, t, &l))
;
return t;
@@ -2107,18 +2068,10 @@ static struct seq_operations show_traces_seq_ops = {
static int show_traces_open(struct inode *inode, struct file *file)
{
- int ret;
-
if (tracing_disabled)
return -ENODEV;
- ret = seq_open(file, &show_traces_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = trace_types;
- }
-
- return ret;
+ return seq_open(file, &show_traces_seq_ops);
}
static ssize_t
@@ -2191,11 +2144,12 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
return -ENOMEM;
- mutex_lock(&tracing_cpumask_update_lock);
err = cpumask_parse_user(ubuf, count, tracing_cpumask_new);
if (err)
goto err_unlock;
+ mutex_lock(&tracing_cpumask_update_lock);
+
local_irq_disable();
__raw_spin_lock(&ftrace_max_lock);
for_each_tracing_cpu(cpu) {
@@ -2223,8 +2177,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
return count;
err_unlock:
- mutex_unlock(&tracing_cpumask_update_lock);
- free_cpumask_var(tracing_cpumask);
+ free_cpumask_var(tracing_cpumask_new);
return err;
}
@@ -2266,8 +2219,8 @@ tracing_trace_options_read(struct file *filp, char __user *ubuf,
len += 3; /* "no" and newline */
}
- /* +2 for \n and \0 */
- buf = kmalloc(len + 2, GFP_KERNEL);
+ /* +1 for \0 */
+ buf = kmalloc(len + 1, GFP_KERNEL);
if (!buf) {
mutex_unlock(&trace_types_lock);
return -ENOMEM;
@@ -2290,7 +2243,7 @@ tracing_trace_options_read(struct file *filp, char __user *ubuf,
}
mutex_unlock(&trace_types_lock);
- WARN_ON(r >= len + 2);
+ WARN_ON(r >= len + 1);
r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
@@ -2301,23 +2254,23 @@ tracing_trace_options_read(struct file *filp, char __user *ubuf,
/* Try to assign a tracer specific option */
static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
{
- struct tracer_flags *trace_flags = trace->flags;
+ struct tracer_flags *tracer_flags = trace->flags;
struct tracer_opt *opts = NULL;
int ret = 0, i = 0;
int len;
- for (i = 0; trace_flags->opts[i].name; i++) {
- opts = &trace_flags->opts[i];
+ for (i = 0; tracer_flags->opts[i].name; i++) {
+ opts = &tracer_flags->opts[i];
len = strlen(opts->name);
if (strncmp(cmp, opts->name, len) == 0) {
- ret = trace->set_flag(trace_flags->val,
+ ret = trace->set_flag(tracer_flags->val,
opts->bit, !neg);
break;
}
}
/* Not found */
- if (!trace_flags->opts[i].name)
+ if (!tracer_flags->opts[i].name)
return -EINVAL;
/* Refused to handle */
@@ -2325,9 +2278,9 @@ static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
return ret;
if (neg)
- trace_flags->val &= ~opts->bit;
+ tracer_flags->val &= ~opts->bit;
else
- trace_flags->val |= opts->bit;
+ tracer_flags->val |= opts->bit;
return 0;
}
@@ -2342,22 +2295,6 @@ static void set_tracer_flags(unsigned int mask, int enabled)
trace_flags |= mask;
else
trace_flags &= ~mask;
-
- if (mask == TRACE_ITER_GLOBAL_CLK) {
- u64 (*func)(void);
-
- if (enabled)
- func = trace_clock_global;
- else
- func = trace_clock_local;
-
- mutex_lock(&trace_types_lock);
- ring_buffer_set_clock(global_trace.buffer, func);
-
- if (max_tr.buffer)
- ring_buffer_set_clock(max_tr.buffer, func);
- mutex_unlock(&trace_types_lock);
- }
}
static ssize_t
@@ -3095,7 +3032,8 @@ tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter)
break;
}
- trace_consume(iter);
+ if (ret != TRACE_TYPE_NO_CONSUME)
+ trace_consume(iter);
rem -= count;
if (!find_next_entry_inc(iter)) {
rem = 0;
@@ -3324,6 +3262,62 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
return cnt;
}
+static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64];
+ int bufiter = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(trace_clocks); i++)
+ bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter,
+ "%s%s%s%s", i ? " " : "",
+ i == trace_clock_id ? "[" : "", trace_clocks[i].name,
+ i == trace_clock_id ? "]" : "");
+ bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n");
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter);
+}
+
+static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *fpos)
+{
+ char buf[64];
+ const char *clockstr;
+ int i;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ clockstr = strstrip(buf);
+
+ for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) {
+ if (strcmp(trace_clocks[i].name, clockstr) == 0)
+ break;
+ }
+ if (i == ARRAY_SIZE(trace_clocks))
+ return -EINVAL;
+
+ trace_clock_id = i;
+
+ mutex_lock(&trace_types_lock);
+
+ ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func);
+ if (max_tr.buffer)
+ ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func);
+
+ mutex_unlock(&trace_types_lock);
+
+ *fpos += cnt;
+
+ return cnt;
+}
+
static const struct file_operations tracing_max_lat_fops = {
.open = tracing_open_generic,
.read = tracing_max_lat_read,
@@ -3361,6 +3355,12 @@ static const struct file_operations tracing_mark_fops = {
.write = tracing_mark_write,
};
+static const struct file_operations trace_clock_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_clock_read,
+ .write = tracing_clock_write,
+};
+
struct ftrace_buffer_info {
struct trace_array *tr;
void *spare;
@@ -3626,7 +3626,7 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
struct trace_seq *s;
unsigned long cnt;
- s = kmalloc(sizeof(*s), GFP_ATOMIC);
+ s = kmalloc(sizeof(*s), GFP_KERNEL);
if (!s)
return ENOMEM;
@@ -3641,9 +3641,6 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu);
trace_seq_printf(s, "commit overrun: %ld\n", cnt);
- cnt = ring_buffer_nmi_dropped_cpu(tr->buffer, cpu);
- trace_seq_printf(s, "nmi dropped: %ld\n", cnt);
-
count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len);
kfree(s);
@@ -3904,17 +3901,9 @@ trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt,
if (ret < 0)
return ret;
- switch (val) {
- case 0:
- trace_flags &= ~(1 << index);
- break;
- case 1:
- trace_flags |= 1 << index;
- break;
-
- default:
+ if (val != 0 && val != 1)
return -EINVAL;
- }
+ set_tracer_flags(1 << index, val);
*ppos += cnt;
@@ -4082,11 +4071,13 @@ static __init int tracer_init_debugfs(void)
trace_create_file("current_tracer", 0644, d_tracer,
&global_trace, &set_tracer_fops);
+#ifdef CONFIG_TRACER_MAX_TRACE
trace_create_file("tracing_max_latency", 0644, d_tracer,
&tracing_max_latency, &tracing_max_lat_fops);
trace_create_file("tracing_thresh", 0644, d_tracer,
&tracing_thresh, &tracing_max_lat_fops);
+#endif
trace_create_file("README", 0444, d_tracer,
NULL, &tracing_readme_fops);
@@ -4103,6 +4094,9 @@ static __init int tracer_init_debugfs(void)
trace_create_file("saved_cmdlines", 0444, d_tracer,
NULL, &tracing_saved_cmdlines_fops);
+ trace_create_file("trace_clock", 0644, d_tracer, NULL,
+ &trace_clock_fops);
+
#ifdef CONFIG_DYNAMIC_FTRACE
trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,
&ftrace_update_tot_cnt, &tracing_dyn_info_fops);
@@ -4243,8 +4237,11 @@ static void __ftrace_dump(bool disable_tracing)
iter.pos = -1;
if (find_next_entry_inc(&iter) != NULL) {
- print_trace_line(&iter);
- trace_consume(&iter);
+ int ret;
+
+ ret = print_trace_line(&iter);
+ if (ret != TRACE_TYPE_NO_CONSUME)
+ trace_consume(&iter);
}
trace_printk_seq(&iter.seq);
@@ -4278,7 +4275,6 @@ void ftrace_dump(void)
__init static int tracer_alloc_buffers(void)
{
- struct trace_array_cpu *data;
int ring_buf_size;
int i;
int ret = -ENOMEM;
@@ -4328,7 +4324,7 @@ __init static int tracer_alloc_buffers(void)
/* Allocate the first page for all buffers */
for_each_tracing_cpu(i) {
- data = global_trace.data[i] = &per_cpu(global_trace_cpu, i);
+ global_trace.data[i] = &per_cpu(global_trace_cpu, i);
max_tr.data[i] = &per_cpu(max_data, i);
}
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index ff1ef411a17..ea7e0bcbd53 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -38,8 +38,6 @@ enum trace_type {
TRACE_GRAPH_ENT,
TRACE_USER_STACK,
TRACE_HW_BRANCHES,
- TRACE_SYSCALL_ENTER,
- TRACE_SYSCALL_EXIT,
TRACE_KMEM_ALLOC,
TRACE_KMEM_FREE,
TRACE_POWER,
@@ -251,9 +249,6 @@ struct trace_array_cpu {
atomic_t disabled;
void *buffer_page; /* ring buffer spare */
- /* these fields get copied into max-trace: */
- unsigned long trace_idx;
- unsigned long overrun;
unsigned long saved_latency;
unsigned long critical_start;
unsigned long critical_end;
@@ -261,6 +256,7 @@ struct trace_array_cpu {
unsigned long nice;
unsigned long policy;
unsigned long rt_priority;
+ unsigned long skipped_entries;
cycle_t preempt_timestamp;
pid_t pid;
uid_t uid;
@@ -334,10 +330,6 @@ extern void __ftrace_bad_type(void);
TRACE_KMEM_ALLOC); \
IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \
TRACE_KMEM_FREE); \
- IF_ASSIGN(var, ent, struct syscall_trace_enter, \
- TRACE_SYSCALL_ENTER); \
- IF_ASSIGN(var, ent, struct syscall_trace_exit, \
- TRACE_SYSCALL_EXIT); \
IF_ASSIGN(var, ent, struct ksym_trace_entry, TRACE_KSYM);\
__ftrace_bad_type(); \
} while (0)
@@ -439,12 +431,13 @@ void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
struct ring_buffer_event;
-struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
- int type,
- unsigned long len,
- unsigned long flags,
- int pc);
-void trace_buffer_unlock_commit(struct trace_array *tr,
+struct ring_buffer_event *
+trace_buffer_lock_reserve(struct ring_buffer *buffer,
+ int type,
+ unsigned long len,
+ unsigned long flags,
+ int pc);
+void trace_buffer_unlock_commit(struct ring_buffer *buffer,
struct ring_buffer_event *event,
unsigned long flags, int pc);
@@ -454,10 +447,6 @@ struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
int *ent_cpu, u64 *ent_ts);
-void tracing_generic_entry_update(struct trace_entry *entry,
- unsigned long flags,
- int pc);
-
void default_wait_pipe(struct trace_iterator *iter);
void poll_wait_pipe(struct trace_iterator *iter);
@@ -487,6 +476,7 @@ void trace_function(struct trace_array *tr,
void trace_graph_return(struct ftrace_graph_ret *trace);
int trace_graph_entry(struct ftrace_graph_ent *trace);
+void set_graph_array(struct trace_array *tr);
void tracing_start_cmdline_record(void);
void tracing_stop_cmdline_record(void);
@@ -498,16 +488,40 @@ void unregister_tracer(struct tracer *type);
extern unsigned long nsecs_to_usecs(unsigned long nsecs);
+#ifdef CONFIG_TRACER_MAX_TRACE
extern unsigned long tracing_max_latency;
extern unsigned long tracing_thresh;
void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
void update_max_tr_single(struct trace_array *tr,
struct task_struct *tsk, int cpu);
+#endif /* CONFIG_TRACER_MAX_TRACE */
+
+#ifdef CONFIG_STACKTRACE
+void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
+ int skip, int pc);
+
+void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
+ int pc);
-void __trace_stack(struct trace_array *tr,
- unsigned long flags,
- int skip, int pc);
+void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
+ int pc);
+#else
+static inline void ftrace_trace_stack(struct trace_array *tr,
+ unsigned long flags, int skip, int pc)
+{
+}
+
+static inline void ftrace_trace_userstack(struct trace_array *tr,
+ unsigned long flags, int pc)
+{
+}
+
+static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
+ int skip, int pc)
+{
+}
+#endif /* CONFIG_STACKTRACE */
extern cycle_t ftrace_now(int cpu);
@@ -533,6 +547,10 @@ extern unsigned long ftrace_update_tot_cnt;
extern int DYN_FTRACE_TEST_NAME(void);
#endif
+extern int ring_buffer_expanded;
+extern bool tracing_selftest_disabled;
+DECLARE_PER_CPU(local_t, ftrace_cpu_disabled);
+
#ifdef CONFIG_FTRACE_STARTUP_TEST
extern int trace_selftest_startup_function(struct tracer *trace,
struct trace_array *tr);
@@ -566,9 +584,16 @@ extern int
trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
extern int
trace_vprintk(unsigned long ip, const char *fmt, va_list args);
+extern int
+trace_array_vprintk(struct trace_array *tr,
+ unsigned long ip, const char *fmt, va_list args);
+int trace_array_printk(struct trace_array *tr,
+ unsigned long ip, const char *fmt, ...);
extern unsigned long trace_flags;
+extern int trace_clock_id;
+
/* Standard output formatting function used for function return traces */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
extern enum print_line_t print_graph_function(struct trace_iterator *iter);
@@ -615,6 +640,7 @@ print_graph_function(struct trace_iterator *iter)
extern struct pid *ftrace_pid_trace;
+#ifdef CONFIG_FUNCTION_TRACER
static inline int ftrace_trace_task(struct task_struct *task)
{
if (!ftrace_pid_trace)
@@ -622,6 +648,12 @@ static inline int ftrace_trace_task(struct task_struct *task)
return test_tsk_trace_trace(task);
}
+#else
+static inline int ftrace_trace_task(struct task_struct *task)
+{
+ return 1;
+}
+#endif
/*
* trace_iterator_flags is an enumeration that defines bit
@@ -650,9 +682,8 @@ enum trace_iterator_flags {
TRACE_ITER_PRINTK_MSGONLY = 0x10000,
TRACE_ITER_CONTEXT_INFO = 0x20000, /* Print pid/cpu/time */
TRACE_ITER_LATENCY_FMT = 0x40000,
- TRACE_ITER_GLOBAL_CLK = 0x80000,
- TRACE_ITER_SLEEP_TIME = 0x100000,
- TRACE_ITER_GRAPH_TIME = 0x200000,
+ TRACE_ITER_SLEEP_TIME = 0x80000,
+ TRACE_ITER_GRAPH_TIME = 0x100000,
};
/*
@@ -749,6 +780,7 @@ struct ftrace_event_field {
struct list_head link;
char *name;
char *type;
+ int filter_type;
int offset;
int size;
int is_signed;
@@ -758,13 +790,15 @@ struct event_filter {
int n_preds;
struct filter_pred **preds;
char *filter_string;
+ bool no_reset;
};
struct event_subsystem {
struct list_head list;
const char *name;
struct dentry *entry;
- void *filter;
+ struct event_filter *filter;
+ int nr_events;
};
struct filter_pred;
@@ -792,6 +826,7 @@ extern int apply_subsystem_event_filter(struct event_subsystem *system,
char *filter_string);
extern void print_subsystem_event_filter(struct event_subsystem *system,
struct trace_seq *s);
+extern int filter_assign_type(const char *type);
static inline int
filter_check_discard(struct ftrace_event_call *call, void *rec,
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index a29ef23ffb4..19bfc75d467 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -41,14 +41,12 @@ void disable_boot_trace(void)
static int boot_trace_init(struct trace_array *tr)
{
- int cpu;
boot_trace = tr;
if (!tr)
return 0;
- for_each_cpu(cpu, cpu_possible_mask)
- tracing_reset(tr, cpu);
+ tracing_reset_online_cpus(tr);
tracing_sched_switch_assign_trace(tr);
return 0;
@@ -132,6 +130,7 @@ struct tracer boot_tracer __read_mostly =
void trace_boot_call(struct boot_trace_call *bt, initcall_t fn)
{
struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
struct trace_boot_call *entry;
struct trace_array *tr = boot_trace;
@@ -144,13 +143,14 @@ void trace_boot_call(struct boot_trace_call *bt, initcall_t fn)
sprint_symbol(bt->func, (unsigned long)fn);
preempt_disable();
- event = trace_buffer_lock_reserve(tr, TRACE_BOOT_CALL,
+ buffer = tr->buffer;
+ event = trace_buffer_lock_reserve(buffer, TRACE_BOOT_CALL,
sizeof(*entry), 0, 0);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
entry->boot_call = *bt;
- trace_buffer_unlock_commit(tr, event, 0, 0);
+ trace_buffer_unlock_commit(buffer, event, 0, 0);
out:
preempt_enable();
}
@@ -158,6 +158,7 @@ void trace_boot_call(struct boot_trace_call *bt, initcall_t fn)
void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn)
{
struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
struct trace_boot_ret *entry;
struct trace_array *tr = boot_trace;
@@ -167,13 +168,14 @@ void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn)
sprint_symbol(bt->func, (unsigned long)fn);
preempt_disable();
- event = trace_buffer_lock_reserve(tr, TRACE_BOOT_RET,
+ buffer = tr->buffer;
+ event = trace_buffer_lock_reserve(buffer, TRACE_BOOT_RET,
sizeof(*entry), 0, 0);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
entry->boot_ret = *bt;
- trace_buffer_unlock_commit(tr, event, 0, 0);
+ trace_buffer_unlock_commit(buffer, event, 0, 0);
out:
preempt_enable();
}
diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c
index 5b5895afecf..11ba5bb4ed0 100644
--- a/kernel/trace/trace_event_profile.c
+++ b/kernel/trace/trace_event_profile.c
@@ -14,7 +14,7 @@ int ftrace_profile_enable(int event_id)
mutex_lock(&event_mutex);
list_for_each_entry(event, &ftrace_events, list) {
- if (event->id == event_id) {
+ if (event->id == event_id && event->profile_enable) {
ret = event->profile_enable(event);
break;
}
diff --git a/kernel/trace/trace_event_types.h b/kernel/trace/trace_event_types.h
index 5e32e375134..6db005e1248 100644
--- a/kernel/trace/trace_event_types.h
+++ b/kernel/trace/trace_event_types.h
@@ -26,6 +26,9 @@ TRACE_EVENT_FORMAT(funcgraph_exit, TRACE_GRAPH_RET,
ftrace_graph_ret_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned long, ret.func, func)
+ TRACE_FIELD(unsigned long long, ret.calltime, calltime)
+ TRACE_FIELD(unsigned long long, ret.rettime, rettime)
+ TRACE_FIELD(unsigned long, ret.overrun, overrun)
TRACE_FIELD(int, ret.depth, depth)
),
TP_RAW_FMT("<-- %lx (%d)")
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index aa08be69a1b..78b1ed23017 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -17,6 +17,8 @@
#include <linux/ctype.h>
#include <linux/delay.h>
+#include <asm/setup.h>
+
#include "trace_output.h"
#define TRACE_SYSTEM "TRACE_SYSTEM"
@@ -25,8 +27,9 @@ DEFINE_MUTEX(event_mutex);
LIST_HEAD(ftrace_events);
-int trace_define_field(struct ftrace_event_call *call, char *type,
- char *name, int offset, int size, int is_signed)
+int trace_define_field(struct ftrace_event_call *call, const char *type,
+ const char *name, int offset, int size, int is_signed,
+ int filter_type)
{
struct ftrace_event_field *field;
@@ -42,9 +45,15 @@ int trace_define_field(struct ftrace_event_call *call, char *type,
if (!field->type)
goto err;
+ if (filter_type == FILTER_OTHER)
+ field->filter_type = filter_assign_type(type);
+ else
+ field->filter_type = filter_type;
+
field->offset = offset;
field->size = size;
field->is_signed = is_signed;
+
list_add(&field->link, &call->fields);
return 0;
@@ -60,6 +69,29 @@ err:
}
EXPORT_SYMBOL_GPL(trace_define_field);
+#define __common_field(type, item) \
+ ret = trace_define_field(call, #type, "common_" #item, \
+ offsetof(typeof(ent), item), \
+ sizeof(ent.item), \
+ is_signed_type(type), FILTER_OTHER); \
+ if (ret) \
+ return ret;
+
+int trace_define_common_fields(struct ftrace_event_call *call)
+{
+ int ret;
+ struct trace_entry ent;
+
+ __common_field(unsigned short, type);
+ __common_field(unsigned char, flags);
+ __common_field(unsigned char, preempt_count);
+ __common_field(int, pid);
+ __common_field(int, tgid);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(trace_define_common_fields);
+
#ifdef CONFIG_MODULES
static void trace_destroy_fields(struct ftrace_event_call *call)
@@ -84,14 +116,14 @@ static void ftrace_event_enable_disable(struct ftrace_event_call *call,
if (call->enabled) {
call->enabled = 0;
tracing_stop_cmdline_record();
- call->unregfunc();
+ call->unregfunc(call->data);
}
break;
case 1:
if (!call->enabled) {
call->enabled = 1;
tracing_start_cmdline_record();
- call->regfunc();
+ call->regfunc(call->data);
}
break;
}
@@ -300,10 +332,18 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
static void *t_start(struct seq_file *m, loff_t *pos)
{
+ struct ftrace_event_call *call = NULL;
+ loff_t l;
+
mutex_lock(&event_mutex);
- if (*pos == 0)
- m->private = ftrace_events.next;
- return t_next(m, NULL, pos);
+
+ m->private = ftrace_events.next;
+ for (l = 0; l <= *pos; ) {
+ call = t_next(m, NULL, &l);
+ if (!call)
+ break;
+ }
+ return call;
}
static void *
@@ -332,10 +372,18 @@ s_next(struct seq_file *m, void *v, loff_t *pos)
static void *s_start(struct seq_file *m, loff_t *pos)
{
+ struct ftrace_event_call *call = NULL;
+ loff_t l;
+
mutex_lock(&event_mutex);
- if (*pos == 0)
- m->private = ftrace_events.next;
- return s_next(m, NULL, pos);
+
+ m->private = ftrace_events.next;
+ for (l = 0; l <= *pos; ) {
+ call = s_next(m, NULL, &l);
+ if (!call)
+ break;
+ }
+ return call;
}
static int t_show(struct seq_file *m, void *v)
@@ -360,7 +408,7 @@ ftrace_event_seq_open(struct inode *inode, struct file *file)
const struct seq_operations *seq_ops;
if ((file->f_mode & FMODE_WRITE) &&
- !(file->f_flags & O_APPEND))
+ (file->f_flags & O_TRUNC))
ftrace_clear_events();
seq_ops = inode->i_private;
@@ -558,7 +606,7 @@ event_format_read(struct file *filp, char __user *ubuf, size_t cnt,
trace_seq_printf(s, "format:\n");
trace_write_header(s);
- r = call->show_format(s);
+ r = call->show_format(call, s);
if (!r) {
/*
* ug! The format output is bigger than a PAGE!!
@@ -833,8 +881,10 @@ event_subsystem_dir(const char *name, struct dentry *d_events)
/* First see if we did not already create this dir */
list_for_each_entry(system, &event_subsystems, list) {
- if (strcmp(system->name, name) == 0)
+ if (strcmp(system->name, name) == 0) {
+ system->nr_events++;
return system->entry;
+ }
}
/* need to create new entry */
@@ -853,6 +903,7 @@ event_subsystem_dir(const char *name, struct dentry *d_events)
return d_events;
}
+ system->nr_events = 1;
system->name = kstrdup(name, GFP_KERNEL);
if (!system->name) {
debugfs_remove(system->entry);
@@ -904,15 +955,6 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
if (strcmp(call->system, TRACE_SYSTEM) != 0)
d_events = event_subsystem_dir(call->system, d_events);
- if (call->raw_init) {
- ret = call->raw_init();
- if (ret < 0) {
- pr_warning("Could not initialize trace point"
- " events/%s\n", call->name);
- return ret;
- }
- }
-
call->dir = debugfs_create_dir(call->name, d_events);
if (!call->dir) {
pr_warning("Could not create debugfs "
@@ -924,12 +966,12 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
entry = trace_create_file("enable", 0644, call->dir, call,
enable);
- if (call->id)
+ if (call->id && call->profile_enable)
entry = trace_create_file("id", 0444, call->dir, call,
id);
if (call->define_fields) {
- ret = call->define_fields();
+ ret = call->define_fields(call);
if (ret < 0) {
pr_warning("Could not initialize trace point"
" events/%s\n", call->name);
@@ -971,6 +1013,32 @@ struct ftrace_module_file_ops {
struct file_operations filter;
};
+static void remove_subsystem_dir(const char *name)
+{
+ struct event_subsystem *system;
+
+ if (strcmp(name, TRACE_SYSTEM) == 0)
+ return;
+
+ list_for_each_entry(system, &event_subsystems, list) {
+ if (strcmp(system->name, name) == 0) {
+ if (!--system->nr_events) {
+ struct event_filter *filter = system->filter;
+
+ debugfs_remove_recursive(system->entry);
+ list_del(&system->list);
+ if (filter) {
+ kfree(filter->filter_string);
+ kfree(filter);
+ }
+ kfree(system->name);
+ kfree(system);
+ }
+ break;
+ }
+ }
+}
+
static struct ftrace_module_file_ops *
trace_create_file_ops(struct module *mod)
{
@@ -1011,6 +1079,7 @@ static void trace_module_add_events(struct module *mod)
struct ftrace_module_file_ops *file_ops = NULL;
struct ftrace_event_call *call, *start, *end;
struct dentry *d_events;
+ int ret;
start = mod->trace_events;
end = mod->trace_events + mod->num_trace_events;
@@ -1026,7 +1095,15 @@ static void trace_module_add_events(struct module *mod)
/* The linker may leave blanks */
if (!call->name)
continue;
-
+ if (call->raw_init) {
+ ret = call->raw_init();
+ if (ret < 0) {
+ if (ret != -ENOSYS)
+ pr_warning("Could not initialize trace "
+ "point events/%s\n", call->name);
+ continue;
+ }
+ }
/*
* This module has events, create file ops for this module
* if not already done.
@@ -1061,6 +1138,7 @@ static void trace_module_remove_events(struct module *mod)
list_del(&call->list);
trace_destroy_fields(call);
destroy_preds(call);
+ remove_subsystem_dir(call->system);
}
}
@@ -1117,6 +1195,18 @@ struct notifier_block trace_module_nb = {
extern struct ftrace_event_call __start_ftrace_events[];
extern struct ftrace_event_call __stop_ftrace_events[];
+static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
+
+static __init int setup_trace_event(char *str)
+{
+ strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE);
+ ring_buffer_expanded = 1;
+ tracing_selftest_disabled = 1;
+
+ return 1;
+}
+__setup("trace_event=", setup_trace_event);
+
static __init int event_trace_init(void)
{
struct ftrace_event_call *call;
@@ -1124,6 +1214,8 @@ static __init int event_trace_init(void)
struct dentry *entry;
struct dentry *d_events;
int ret;
+ char *buf = bootup_event_buf;
+ char *token;
d_tracer = tracing_init_dentry();
if (!d_tracer)
@@ -1163,12 +1255,34 @@ static __init int event_trace_init(void)
/* The linker may leave blanks */
if (!call->name)
continue;
+ if (call->raw_init) {
+ ret = call->raw_init();
+ if (ret < 0) {
+ if (ret != -ENOSYS)
+ pr_warning("Could not initialize trace "
+ "point events/%s\n", call->name);
+ continue;
+ }
+ }
list_add(&call->list, &ftrace_events);
event_create_dir(call, d_events, &ftrace_event_id_fops,
&ftrace_enable_fops, &ftrace_event_filter_fops,
&ftrace_event_format_fops);
}
+ while (true) {
+ token = strsep(&buf, ",");
+
+ if (!token)
+ break;
+ if (!*token)
+ continue;
+
+ ret = ftrace_set_clr_event(token, 1);
+ if (ret)
+ pr_warning("Failed to enable trace event: %s\n", token);
+ }
+
ret = register_module_notifier(&trace_module_nb);
if (ret)
pr_warning("Failed to register trace events module notifier\n");
@@ -1324,6 +1438,7 @@ static void
function_test_events_call(unsigned long ip, unsigned long parent_ip)
{
struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
struct ftrace_entry *entry;
unsigned long flags;
long disabled;
@@ -1341,7 +1456,8 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip)
local_save_flags(flags);
- event = trace_current_buffer_lock_reserve(TRACE_FN, sizeof(*entry),
+ event = trace_current_buffer_lock_reserve(&buffer,
+ TRACE_FN, sizeof(*entry),
flags, pc);
if (!event)
goto out;
@@ -1349,7 +1465,7 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip)
entry->ip = ip;
entry->parent_ip = parent_ip;
- trace_nowake_buffer_unlock_commit(event, flags, pc);
+ trace_nowake_buffer_unlock_commit(buffer, event, flags, pc);
out:
atomic_dec(&per_cpu(test_event_disable, cpu));
@@ -1376,10 +1492,10 @@ static __init void event_trace_self_test_with_function(void)
static __init int event_trace_self_tests_init(void)
{
-
- event_trace_self_tests();
-
- event_trace_self_test_with_function();
+ if (!tracing_selftest_disabled) {
+ event_trace_self_tests();
+ event_trace_self_test_with_function();
+ }
return 0;
}
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index db6e54bdb59..93660fbbf62 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -27,8 +27,6 @@
#include "trace.h"
#include "trace_output.h"
-static DEFINE_MUTEX(filter_mutex);
-
enum filter_op_ids
{
OP_OR,
@@ -165,6 +163,20 @@ static int filter_pred_string(struct filter_pred *pred, void *event,
return match;
}
+/* Filter predicate for char * pointers */
+static int filter_pred_pchar(struct filter_pred *pred, void *event,
+ int val1, int val2)
+{
+ char **addr = (char **)(event + pred->offset);
+ int cmp, match;
+
+ cmp = strncmp(*addr, pred->str_val, pred->str_len);
+
+ match = (!cmp) ^ pred->not;
+
+ return match;
+}
+
/*
* Filter predicate for dynamic sized arrays of characters.
* These are implemented through a list of strings at the end
@@ -178,11 +190,13 @@ static int filter_pred_string(struct filter_pred *pred, void *event,
static int filter_pred_strloc(struct filter_pred *pred, void *event,
int val1, int val2)
{
- int str_loc = *(int *)(event + pred->offset);
+ u32 str_item = *(u32 *)(event + pred->offset);
+ int str_loc = str_item & 0xffff;
+ int str_len = str_item >> 16;
char *addr = (char *)(event + str_loc);
int cmp, match;
- cmp = strncmp(addr, pred->str_val, pred->str_len);
+ cmp = strncmp(addr, pred->str_val, str_len);
match = (!cmp) ^ pred->not;
@@ -294,12 +308,12 @@ void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s)
{
struct event_filter *filter = call->filter;
- mutex_lock(&filter_mutex);
- if (filter->filter_string)
+ mutex_lock(&event_mutex);
+ if (filter && filter->filter_string)
trace_seq_printf(s, "%s\n", filter->filter_string);
else
trace_seq_printf(s, "none\n");
- mutex_unlock(&filter_mutex);
+ mutex_unlock(&event_mutex);
}
void print_subsystem_event_filter(struct event_subsystem *system,
@@ -307,12 +321,12 @@ void print_subsystem_event_filter(struct event_subsystem *system,
{
struct event_filter *filter = system->filter;
- mutex_lock(&filter_mutex);
- if (filter->filter_string)
+ mutex_lock(&event_mutex);
+ if (filter && filter->filter_string)
trace_seq_printf(s, "%s\n", filter->filter_string);
else
trace_seq_printf(s, "none\n");
- mutex_unlock(&filter_mutex);
+ mutex_unlock(&event_mutex);
}
static struct ftrace_event_field *
@@ -376,26 +390,32 @@ void destroy_preds(struct ftrace_event_call *call)
struct event_filter *filter = call->filter;
int i;
+ if (!filter)
+ return;
+
for (i = 0; i < MAX_FILTER_PRED; i++) {
if (filter->preds[i])
filter_free_pred(filter->preds[i]);
}
kfree(filter->preds);
+ kfree(filter->filter_string);
kfree(filter);
call->filter = NULL;
}
-int init_preds(struct ftrace_event_call *call)
+static int init_preds(struct ftrace_event_call *call)
{
struct event_filter *filter;
struct filter_pred *pred;
int i;
+ if (call->filter)
+ return 0;
+
filter = call->filter = kzalloc(sizeof(*filter), GFP_KERNEL);
if (!call->filter)
return -ENOMEM;
- call->filter_active = 0;
filter->n_preds = 0;
filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), GFP_KERNEL);
@@ -417,33 +437,56 @@ oom:
return -ENOMEM;
}
-EXPORT_SYMBOL_GPL(init_preds);
-static void filter_free_subsystem_preds(struct event_subsystem *system)
+static int init_subsystem_preds(struct event_subsystem *system)
{
- struct event_filter *filter = system->filter;
struct ftrace_event_call *call;
- int i;
+ int err;
- if (filter->n_preds) {
- for (i = 0; i < filter->n_preds; i++)
- filter_free_pred(filter->preds[i]);
- kfree(filter->preds);
- filter->preds = NULL;
- filter->n_preds = 0;
+ list_for_each_entry(call, &ftrace_events, list) {
+ if (!call->define_fields)
+ continue;
+
+ if (strcmp(call->system, system->name) != 0)
+ continue;
+
+ err = init_preds(call);
+ if (err)
+ return err;
}
- mutex_lock(&event_mutex);
+ return 0;
+}
+
+enum {
+ FILTER_DISABLE_ALL,
+ FILTER_INIT_NO_RESET,
+ FILTER_SKIP_NO_RESET,
+};
+
+static void filter_free_subsystem_preds(struct event_subsystem *system,
+ int flag)
+{
+ struct ftrace_event_call *call;
+
list_for_each_entry(call, &ftrace_events, list) {
if (!call->define_fields)
continue;
- if (!strcmp(call->system, system->name)) {
- filter_disable_preds(call);
- remove_filter_string(call->filter);
+ if (strcmp(call->system, system->name) != 0)
+ continue;
+
+ if (flag == FILTER_INIT_NO_RESET) {
+ call->filter->no_reset = false;
+ continue;
}
+
+ if (flag == FILTER_SKIP_NO_RESET && call->filter->no_reset)
+ continue;
+
+ filter_disable_preds(call);
+ remove_filter_string(call->filter);
}
- mutex_unlock(&event_mutex);
}
static int filter_add_pred_fn(struct filter_parse_state *ps,
@@ -471,12 +514,7 @@ static int filter_add_pred_fn(struct filter_parse_state *ps,
return 0;
}
-enum {
- FILTER_STATIC_STRING = 1,
- FILTER_DYN_STRING
-};
-
-static int is_string_field(const char *type)
+int filter_assign_type(const char *type)
{
if (strstr(type, "__data_loc") && strstr(type, "char"))
return FILTER_DYN_STRING;
@@ -484,12 +522,19 @@ static int is_string_field(const char *type)
if (strchr(type, '[') && strstr(type, "char"))
return FILTER_STATIC_STRING;
- return 0;
+ return FILTER_OTHER;
+}
+
+static bool is_string_field(struct ftrace_event_field *field)
+{
+ return field->filter_type == FILTER_DYN_STRING ||
+ field->filter_type == FILTER_STATIC_STRING ||
+ field->filter_type == FILTER_PTR_STRING;
}
static int is_legal_op(struct ftrace_event_field *field, int op)
{
- if (is_string_field(field->type) && (op != OP_EQ && op != OP_NE))
+ if (is_string_field(field) && (op != OP_EQ && op != OP_NE))
return 0;
return 1;
@@ -540,21 +585,24 @@ static filter_pred_fn_t select_comparison_fn(int op, int field_size,
static int filter_add_pred(struct filter_parse_state *ps,
struct ftrace_event_call *call,
- struct filter_pred *pred)
+ struct filter_pred *pred,
+ bool dry_run)
{
struct ftrace_event_field *field;
filter_pred_fn_t fn;
unsigned long long val;
- int string_type;
+ int ret;
pred->fn = filter_pred_none;
if (pred->op == OP_AND) {
pred->pop_n = 2;
- return filter_add_pred_fn(ps, call, pred, filter_pred_and);
+ fn = filter_pred_and;
+ goto add_pred_fn;
} else if (pred->op == OP_OR) {
pred->pop_n = 2;
- return filter_add_pred_fn(ps, call, pred, filter_pred_or);
+ fn = filter_pred_or;
+ goto add_pred_fn;
}
field = find_event_field(call, pred->field_name);
@@ -570,62 +618,55 @@ static int filter_add_pred(struct filter_parse_state *ps,
return -EINVAL;
}
- string_type = is_string_field(field->type);
- if (string_type) {
- if (string_type == FILTER_STATIC_STRING)
+ if (is_string_field(field)) {
+ pred->str_len = field->size;
+
+ if (field->filter_type == FILTER_STATIC_STRING)
fn = filter_pred_string;
- else
+ else if (field->filter_type == FILTER_DYN_STRING)
fn = filter_pred_strloc;
- pred->str_len = field->size;
- if (pred->op == OP_NE)
- pred->not = 1;
- return filter_add_pred_fn(ps, call, pred, fn);
+ else {
+ fn = filter_pred_pchar;
+ pred->str_len = strlen(pred->str_val);
+ }
} else {
- if (strict_strtoull(pred->str_val, 0, &val)) {
+ if (field->is_signed)
+ ret = strict_strtoll(pred->str_val, 0, &val);
+ else
+ ret = strict_strtoull(pred->str_val, 0, &val);
+ if (ret) {
parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0);
return -EINVAL;
}
pred->val = val;
- }
- fn = select_comparison_fn(pred->op, field->size, field->is_signed);
- if (!fn) {
- parse_error(ps, FILT_ERR_INVALID_OP, 0);
- return -EINVAL;
+ fn = select_comparison_fn(pred->op, field->size,
+ field->is_signed);
+ if (!fn) {
+ parse_error(ps, FILT_ERR_INVALID_OP, 0);
+ return -EINVAL;
+ }
}
if (pred->op == OP_NE)
pred->not = 1;
- return filter_add_pred_fn(ps, call, pred, fn);
+add_pred_fn:
+ if (!dry_run)
+ return filter_add_pred_fn(ps, call, pred, fn);
+ return 0;
}
static int filter_add_subsystem_pred(struct filter_parse_state *ps,
struct event_subsystem *system,
struct filter_pred *pred,
- char *filter_string)
+ char *filter_string,
+ bool dry_run)
{
- struct event_filter *filter = system->filter;
struct ftrace_event_call *call;
int err = 0;
+ bool fail = true;
- if (!filter->preds) {
- filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred),
- GFP_KERNEL);
-
- if (!filter->preds)
- return -ENOMEM;
- }
-
- if (filter->n_preds == MAX_FILTER_PRED) {
- parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
- return -ENOSPC;
- }
-
- filter->preds[filter->n_preds] = pred;
- filter->n_preds++;
-
- mutex_lock(&event_mutex);
list_for_each_entry(call, &ftrace_events, list) {
if (!call->define_fields)
@@ -634,18 +675,24 @@ static int filter_add_subsystem_pred(struct filter_parse_state *ps,
if (strcmp(call->system, system->name))
continue;
- err = filter_add_pred(ps, call, pred);
- if (err) {
- mutex_unlock(&event_mutex);
- filter_free_subsystem_preds(system);
- parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
- goto out;
- }
- replace_filter_string(call->filter, filter_string);
+ if (call->filter->no_reset)
+ continue;
+
+ err = filter_add_pred(ps, call, pred, dry_run);
+ if (err)
+ call->filter->no_reset = true;
+ else
+ fail = false;
+
+ if (!dry_run)
+ replace_filter_string(call->filter, filter_string);
}
- mutex_unlock(&event_mutex);
-out:
- return err;
+
+ if (fail) {
+ parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
+ return err;
+ }
+ return 0;
}
static void parse_init(struct filter_parse_state *ps,
@@ -1004,12 +1051,14 @@ static int check_preds(struct filter_parse_state *ps)
static int replace_preds(struct event_subsystem *system,
struct ftrace_event_call *call,
struct filter_parse_state *ps,
- char *filter_string)
+ char *filter_string,
+ bool dry_run)
{
char *operand1 = NULL, *operand2 = NULL;
struct filter_pred *pred;
struct postfix_elt *elt;
int err;
+ int n_preds = 0;
err = check_preds(ps);
if (err)
@@ -1028,19 +1077,14 @@ static int replace_preds(struct event_subsystem *system,
continue;
}
+ if (n_preds++ == MAX_FILTER_PRED) {
+ parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
+ return -ENOSPC;
+ }
+
if (elt->op == OP_AND || elt->op == OP_OR) {
pred = create_logical_pred(elt->op);
- if (call) {
- err = filter_add_pred(ps, call, pred);
- filter_free_pred(pred);
- } else
- err = filter_add_subsystem_pred(ps, system,
- pred, filter_string);
- if (err)
- return err;
-
- operand1 = operand2 = NULL;
- continue;
+ goto add_pred;
}
if (!operand1 || !operand2) {
@@ -1049,12 +1093,15 @@ static int replace_preds(struct event_subsystem *system,
}
pred = create_pred(elt->op, operand1, operand2);
- if (call) {
- err = filter_add_pred(ps, call, pred);
- filter_free_pred(pred);
- } else
+add_pred:
+ if (!pred)
+ return -ENOMEM;
+ if (call)
+ err = filter_add_pred(ps, call, pred, false);
+ else
err = filter_add_subsystem_pred(ps, system, pred,
- filter_string);
+ filter_string, dry_run);
+ filter_free_pred(pred);
if (err)
return err;
@@ -1070,12 +1117,16 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
struct filter_parse_state *ps;
- mutex_lock(&filter_mutex);
+ mutex_lock(&event_mutex);
+
+ err = init_preds(call);
+ if (err)
+ goto out_unlock;
if (!strcmp(strstrip(filter_string), "0")) {
filter_disable_preds(call);
remove_filter_string(call->filter);
- mutex_unlock(&filter_mutex);
+ mutex_unlock(&event_mutex);
return 0;
}
@@ -1094,7 +1145,7 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
goto out;
}
- err = replace_preds(NULL, call, ps, filter_string);
+ err = replace_preds(NULL, call, ps, filter_string, false);
if (err)
append_filter_err(ps, call->filter);
@@ -1103,7 +1154,7 @@ out:
postfix_clear(ps);
kfree(ps);
out_unlock:
- mutex_unlock(&filter_mutex);
+ mutex_unlock(&event_mutex);
return err;
}
@@ -1115,12 +1166,16 @@ int apply_subsystem_event_filter(struct event_subsystem *system,
struct filter_parse_state *ps;
- mutex_lock(&filter_mutex);
+ mutex_lock(&event_mutex);
+
+ err = init_subsystem_preds(system);
+ if (err)
+ goto out_unlock;
if (!strcmp(strstrip(filter_string), "0")) {
- filter_free_subsystem_preds(system);
+ filter_free_subsystem_preds(system, FILTER_DISABLE_ALL);
remove_filter_string(system->filter);
- mutex_unlock(&filter_mutex);
+ mutex_unlock(&event_mutex);
return 0;
}
@@ -1129,7 +1184,6 @@ int apply_subsystem_event_filter(struct event_subsystem *system,
if (!ps)
goto out_unlock;
- filter_free_subsystem_preds(system);
replace_filter_string(system->filter, filter_string);
parse_init(ps, filter_ops, filter_string);
@@ -1139,16 +1193,30 @@ int apply_subsystem_event_filter(struct event_subsystem *system,
goto out;
}
- err = replace_preds(system, NULL, ps, filter_string);
- if (err)
+ filter_free_subsystem_preds(system, FILTER_INIT_NO_RESET);
+
+ /* try to see the filter can be applied to which events */
+ err = replace_preds(system, NULL, ps, filter_string, true);
+ if (err) {
append_filter_err(ps, system->filter);
+ goto out;
+ }
+
+ filter_free_subsystem_preds(system, FILTER_SKIP_NO_RESET);
+
+ /* really apply the filter to the events */
+ err = replace_preds(system, NULL, ps, filter_string, false);
+ if (err) {
+ append_filter_err(ps, system->filter);
+ filter_free_subsystem_preds(system, 2);
+ }
out:
filter_opstack_clear(ps);
postfix_clear(ps);
kfree(ps);
out_unlock:
- mutex_unlock(&filter_mutex);
+ mutex_unlock(&event_mutex);
return err;
}
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index d06cf898dc8..df1bf6e48bb 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -60,7 +60,8 @@ extern void __bad_type_size(void);
#undef TRACE_EVENT_FORMAT
#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
static int \
-ftrace_format_##call(struct trace_seq *s) \
+ftrace_format_##call(struct ftrace_event_call *unused, \
+ struct trace_seq *s) \
{ \
struct args field; \
int ret; \
@@ -76,7 +77,8 @@ ftrace_format_##call(struct trace_seq *s) \
#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, \
tpfmt) \
static int \
-ftrace_format_##call(struct trace_seq *s) \
+ftrace_format_##call(struct ftrace_event_call *unused, \
+ struct trace_seq *s) \
{ \
struct args field; \
int ret; \
@@ -117,7 +119,7 @@ ftrace_format_##call(struct trace_seq *s) \
#undef TRACE_EVENT_FORMAT
#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
-int ftrace_define_fields_##call(void); \
+int ftrace_define_fields_##call(struct ftrace_event_call *event_call); \
static int ftrace_raw_init_event_##call(void); \
\
struct ftrace_event_call __used \
@@ -133,7 +135,6 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
static int ftrace_raw_init_event_##call(void) \
{ \
INIT_LIST_HEAD(&event_##call.fields); \
- init_preds(&event_##call); \
return 0; \
} \
@@ -156,7 +157,8 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
#define TRACE_FIELD(type, item, assign) \
ret = trace_define_field(event_call, #type, #item, \
offsetof(typeof(field), item), \
- sizeof(field.item), is_signed_type(type)); \
+ sizeof(field.item), \
+ is_signed_type(type), FILTER_OTHER); \
if (ret) \
return ret;
@@ -164,7 +166,7 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
#define TRACE_FIELD_SPECIAL(type, item, len, cmd) \
ret = trace_define_field(event_call, #type "[" #len "]", #item, \
offsetof(typeof(field), item), \
- sizeof(field.item), 0); \
+ sizeof(field.item), 0, FILTER_OTHER); \
if (ret) \
return ret;
@@ -172,7 +174,8 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
#define TRACE_FIELD_SIGN(type, item, assign, is_signed) \
ret = trace_define_field(event_call, #type, #item, \
offsetof(typeof(field), item), \
- sizeof(field.item), is_signed); \
+ sizeof(field.item), is_signed, \
+ FILTER_OTHER); \
if (ret) \
return ret;
@@ -182,17 +185,14 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
#undef TRACE_EVENT_FORMAT
#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
int \
-ftrace_define_fields_##call(void) \
+ftrace_define_fields_##call(struct ftrace_event_call *event_call) \
{ \
- struct ftrace_event_call *event_call = &event_##call; \
struct args field; \
int ret; \
\
- __common_field(unsigned char, type, 0); \
- __common_field(unsigned char, flags, 0); \
- __common_field(unsigned char, preempt_count, 0); \
- __common_field(int, pid, 1); \
- __common_field(int, tgid, 1); \
+ ret = trace_define_common_fields(event_call); \
+ if (ret) \
+ return ret; \
\
tstruct; \
\
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index c9a0b7df44f..5b01b94518f 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -193,9 +193,11 @@ static void tracing_start_function_trace(void)
static void tracing_stop_function_trace(void)
{
ftrace_function_enabled = 0;
- /* OK if they are not registered */
- unregister_ftrace_function(&trace_stack_ops);
- unregister_ftrace_function(&trace_ops);
+
+ if (func_flags.val & TRACE_FUNC_OPT_STACK)
+ unregister_ftrace_function(&trace_stack_ops);
+ else
+ unregister_ftrace_function(&trace_ops);
}
static int func_set_flag(u32 old_flags, u32 bit, int set)
@@ -286,11 +288,9 @@ static int
ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
struct ftrace_probe_ops *ops, void *data)
{
- char str[KSYM_SYMBOL_LEN];
long count = (long)data;
- kallsyms_lookup(ip, NULL, NULL, NULL, str);
- seq_printf(m, "%s:", str);
+ seq_printf(m, "%pf:", (void *)ip);
if (ops == &traceon_probe_ops)
seq_printf(m, "traceon");
@@ -300,8 +300,7 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
if (count == -1)
seq_printf(m, ":unlimited\n");
else
- seq_printf(m, ":count=%ld", count);
- seq_putc(m, '\n');
+ seq_printf(m, ":count=%ld\n", count);
return 0;
}
@@ -362,7 +361,7 @@ ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable)
out_reg:
ret = register_ftrace_function_probe(glob, ops, count);
- return ret;
+ return ret < 0 ? ret : 0;
}
static struct ftrace_func_command ftrace_traceon_cmd = {
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 8b592418d8b..b3749a2c313 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -52,12 +52,13 @@ static struct tracer_flags tracer_flags = {
.opts = trace_opts
};
-/* pid on the last trace processed */
+static struct trace_array *graph_array;
/* Add a function return address to the trace stack on thread info.*/
int
-ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth)
+ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
+ unsigned long frame_pointer)
{
unsigned long long calltime;
int index;
@@ -85,6 +86,7 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth)
current->ret_stack[index].func = func;
current->ret_stack[index].calltime = calltime;
current->ret_stack[index].subtime = 0;
+ current->ret_stack[index].fp = frame_pointer;
*depth = index;
return 0;
@@ -92,7 +94,8 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth)
/* Retrieve a function return address to the trace stack on thread info.*/
static void
-ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret)
+ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
+ unsigned long frame_pointer)
{
int index;
@@ -106,6 +109,31 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret)
return;
}
+#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST
+ /*
+ * The arch may choose to record the frame pointer used
+ * and check it here to make sure that it is what we expect it
+ * to be. If gcc does not set the place holder of the return
+ * address in the frame pointer, and does a copy instead, then
+ * the function graph trace will fail. This test detects this
+ * case.
+ *
+ * Currently, x86_32 with optimize for size (-Os) makes the latest
+ * gcc do the above.
+ */
+ if (unlikely(current->ret_stack[index].fp != frame_pointer)) {
+ ftrace_graph_stop();
+ WARN(1, "Bad frame pointer: expected %lx, received %lx\n"
+ " from func %pF return to %lx\n",
+ current->ret_stack[index].fp,
+ frame_pointer,
+ (void *)current->ret_stack[index].func,
+ current->ret_stack[index].ret);
+ *ret = (unsigned long)panic;
+ return;
+ }
+#endif
+
*ret = current->ret_stack[index].ret;
trace->func = current->ret_stack[index].func;
trace->calltime = current->ret_stack[index].calltime;
@@ -117,12 +145,12 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret)
* Send the trace to the ring-buffer.
* @return the original return address.
*/
-unsigned long ftrace_return_to_handler(void)
+unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
{
struct ftrace_graph_ret trace;
unsigned long ret;
- ftrace_pop_return_trace(&trace, &ret);
+ ftrace_pop_return_trace(&trace, &ret, frame_pointer);
trace.rettime = trace_clock_local();
ftrace_graph_return(&trace);
barrier();
@@ -138,10 +166,123 @@ unsigned long ftrace_return_to_handler(void)
return ret;
}
+static int __trace_graph_entry(struct trace_array *tr,
+ struct ftrace_graph_ent *trace,
+ unsigned long flags,
+ int pc)
+{
+ struct ftrace_event_call *call = &event_funcgraph_entry;
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer = tr->buffer;
+ struct ftrace_graph_ent_entry *entry;
+
+ if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
+ return 0;
+
+ event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_ENT,
+ sizeof(*entry), flags, pc);
+ if (!event)
+ return 0;
+ entry = ring_buffer_event_data(event);
+ entry->graph_ent = *trace;
+ if (!filter_current_check_discard(buffer, call, entry, event))
+ ring_buffer_unlock_commit(buffer, event);
+
+ return 1;
+}
+
+int trace_graph_entry(struct ftrace_graph_ent *trace)
+{
+ struct trace_array *tr = graph_array;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int ret;
+ int cpu;
+ int pc;
+
+ if (unlikely(!tr))
+ return 0;
+
+ if (!ftrace_trace_task(current))
+ return 0;
+
+ if (!ftrace_graph_addr(trace->func))
+ return 0;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+ if (likely(disabled == 1)) {
+ pc = preempt_count();
+ ret = __trace_graph_entry(tr, trace, flags, pc);
+ } else {
+ ret = 0;
+ }
+ /* Only do the atomic if it is not already set */
+ if (!test_tsk_trace_graph(current))
+ set_tsk_trace_graph(current);
+
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
+
+ return ret;
+}
+
+static void __trace_graph_return(struct trace_array *tr,
+ struct ftrace_graph_ret *trace,
+ unsigned long flags,
+ int pc)
+{
+ struct ftrace_event_call *call = &event_funcgraph_exit;
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer = tr->buffer;
+ struct ftrace_graph_ret_entry *entry;
+
+ if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
+ return;
+
+ event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_RET,
+ sizeof(*entry), flags, pc);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ entry->ret = *trace;
+ if (!filter_current_check_discard(buffer, call, entry, event))
+ ring_buffer_unlock_commit(buffer, event);
+}
+
+void trace_graph_return(struct ftrace_graph_ret *trace)
+{
+ struct trace_array *tr = graph_array;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+ int pc;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+ if (likely(disabled == 1)) {
+ pc = preempt_count();
+ __trace_graph_return(tr, trace, flags, pc);
+ }
+ if (!trace->depth)
+ clear_tsk_trace_graph(current);
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
+}
+
static int graph_trace_init(struct trace_array *tr)
{
- int ret = register_ftrace_graph(&trace_graph_return,
- &trace_graph_entry);
+ int ret;
+
+ graph_array = tr;
+ ret = register_ftrace_graph(&trace_graph_return,
+ &trace_graph_entry);
if (ret)
return ret;
tracing_start_cmdline_record();
@@ -149,49 +290,30 @@ static int graph_trace_init(struct trace_array *tr)
return 0;
}
+void set_graph_array(struct trace_array *tr)
+{
+ graph_array = tr;
+}
+
static void graph_trace_reset(struct trace_array *tr)
{
tracing_stop_cmdline_record();
unregister_ftrace_graph();
}
-static inline int log10_cpu(int nb)
-{
- if (nb / 100)
- return 3;
- if (nb / 10)
- return 2;
- return 1;
-}
+static int max_bytes_for_cpu;
static enum print_line_t
print_graph_cpu(struct trace_seq *s, int cpu)
{
- int i;
int ret;
- int log10_this = log10_cpu(cpu);
- int log10_all = log10_cpu(cpumask_weight(cpu_online_mask));
-
/*
* Start with a space character - to make it stand out
* to the right a bit when trace output is pasted into
* email:
*/
- ret = trace_seq_printf(s, " ");
-
- /*
- * Tricky - we space the CPU field according to the max
- * number of online CPUs. On a 2-cpu system it would take
- * a maximum of 1 digit - on a 128 cpu system it would
- * take up to 3 digits:
- */
- for (i = 0; i < log10_all - log10_this; i++) {
- ret = trace_seq_printf(s, " ");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- }
- ret = trace_seq_printf(s, "%d) ", cpu);
+ ret = trace_seq_printf(s, " %*d) ", max_bytes_for_cpu, cpu);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
@@ -537,11 +659,7 @@ print_graph_entry_leaf(struct trace_iterator *iter,
return TRACE_TYPE_PARTIAL_LINE;
}
- ret = seq_print_ip_sym(s, call->func, 0);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- ret = trace_seq_printf(s, "();\n");
+ ret = trace_seq_printf(s, "%pf();\n", (void *)call->func);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
@@ -584,11 +702,7 @@ print_graph_entry_nested(struct trace_iterator *iter,
return TRACE_TYPE_PARTIAL_LINE;
}
- ret = seq_print_ip_sym(s, call->func, 0);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- ret = trace_seq_printf(s, "() {\n");
+ ret = trace_seq_printf(s, "%pf() {\n", (void *)call->func);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
@@ -815,9 +929,16 @@ print_graph_function(struct trace_iterator *iter)
switch (entry->type) {
case TRACE_GRAPH_ENT: {
- struct ftrace_graph_ent_entry *field;
+ /*
+ * print_graph_entry() may consume the current event,
+ * thus @field may become invalid, so we need to save it.
+ * sizeof(struct ftrace_graph_ent_entry) is very small,
+ * it can be safely saved at the stack.
+ */
+ struct ftrace_graph_ent_entry *field, saved;
trace_assign_type(field, entry);
- return print_graph_entry(field, s, iter);
+ saved = *field;
+ return print_graph_entry(&saved, s, iter);
}
case TRACE_GRAPH_RET: {
struct ftrace_graph_ret_entry *field;
@@ -899,6 +1020,8 @@ static struct tracer graph_trace __read_mostly = {
static __init int init_graph_trace(void)
{
+ max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
+
return register_tracer(&graph_trace);
}
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index b923d13e2fa..5555b75a0d1 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -178,7 +178,6 @@ out_unlock:
out:
data->critical_sequence = max_sequence;
data->preempt_timestamp = ftrace_now(cpu);
- tracing_reset(tr, cpu);
trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
}
@@ -208,7 +207,6 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip)
data->critical_sequence = max_sequence;
data->preempt_timestamp = ftrace_now(cpu);
data->critical_start = parent_ip ? : ip;
- tracing_reset(tr, cpu);
local_save_flags(flags);
@@ -379,6 +377,7 @@ static void __irqsoff_tracer_init(struct trace_array *tr)
irqsoff_trace = tr;
/* make sure that the tracer is visible */
smp_wmb();
+ tracing_reset_online_cpus(tr);
start_irqsoff_tracer(tr);
}
diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
index d53b45ed080..c4c9bbda53d 100644
--- a/kernel/trace/trace_mmiotrace.c
+++ b/kernel/trace/trace_mmiotrace.c
@@ -307,11 +307,12 @@ static void __trace_mmiotrace_rw(struct trace_array *tr,
struct trace_array_cpu *data,
struct mmiotrace_rw *rw)
{
+ struct ring_buffer *buffer = tr->buffer;
struct ring_buffer_event *event;
struct trace_mmiotrace_rw *entry;
int pc = preempt_count();
- event = trace_buffer_lock_reserve(tr, TRACE_MMIO_RW,
+ event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_RW,
sizeof(*entry), 0, pc);
if (!event) {
atomic_inc(&dropped_count);
@@ -319,7 +320,7 @@ static void __trace_mmiotrace_rw(struct trace_array *tr,
}
entry = ring_buffer_event_data(event);
entry->rw = *rw;
- trace_buffer_unlock_commit(tr, event, 0, pc);
+ trace_buffer_unlock_commit(buffer, event, 0, pc);
}
void mmio_trace_rw(struct mmiotrace_rw *rw)
@@ -333,11 +334,12 @@ static void __trace_mmiotrace_map(struct trace_array *tr,
struct trace_array_cpu *data,
struct mmiotrace_map *map)
{
+ struct ring_buffer *buffer = tr->buffer;
struct ring_buffer_event *event;
struct trace_mmiotrace_map *entry;
int pc = preempt_count();
- event = trace_buffer_lock_reserve(tr, TRACE_MMIO_MAP,
+ event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_MAP,
sizeof(*entry), 0, pc);
if (!event) {
atomic_inc(&dropped_count);
@@ -345,7 +347,7 @@ static void __trace_mmiotrace_map(struct trace_array *tr,
}
entry = ring_buffer_event_data(event);
entry->map = *map;
- trace_buffer_unlock_commit(tr, event, 0, pc);
+ trace_buffer_unlock_commit(buffer, event, 0, pc);
}
void mmio_trace_mapping(struct mmiotrace_map *map)
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 7938f3ae93e..e0c2545622e 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -27,8 +27,7 @@ void trace_print_seq(struct seq_file *m, struct trace_seq *s)
{
int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
- s->buffer[len] = 0;
- seq_puts(m, s->buffer);
+ seq_write(m, s->buffer, len);
trace_seq_init(s);
}
diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c
index 8a30d9874cd..fe1a00f1445 100644
--- a/kernel/trace/trace_power.c
+++ b/kernel/trace/trace_power.c
@@ -38,6 +38,7 @@ static void probe_power_end(struct power_trace *it)
{
struct ftrace_event_call *call = &event_power;
struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
struct trace_power *entry;
struct trace_array_cpu *data;
struct trace_array *tr = power_trace;
@@ -45,18 +46,20 @@ static void probe_power_end(struct power_trace *it)
if (!trace_power_enabled)
return;
+ buffer = tr->buffer;
+
preempt_disable();
it->end = ktime_get();
data = tr->data[smp_processor_id()];
- event = trace_buffer_lock_reserve(tr, TRACE_POWER,
+ event = trace_buffer_lock_reserve(buffer, TRACE_POWER,
sizeof(*entry), 0, 0);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
entry->state_data = *it;
- if (!filter_check_discard(call, entry, tr->buffer, event))
- trace_buffer_unlock_commit(tr, event, 0, 0);
+ if (!filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, 0, 0);
out:
preempt_enable();
}
@@ -66,6 +69,7 @@ static void probe_power_mark(struct power_trace *it, unsigned int type,
{
struct ftrace_event_call *call = &event_power;
struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
struct trace_power *entry;
struct trace_array_cpu *data;
struct trace_array *tr = power_trace;
@@ -73,6 +77,8 @@ static void probe_power_mark(struct power_trace *it, unsigned int type,
if (!trace_power_enabled)
return;
+ buffer = tr->buffer;
+
memset(it, 0, sizeof(struct power_trace));
it->state = level;
it->type = type;
@@ -81,14 +87,14 @@ static void probe_power_mark(struct power_trace *it, unsigned int type,
it->end = it->stamp;
data = tr->data[smp_processor_id()];
- event = trace_buffer_lock_reserve(tr, TRACE_POWER,
+ event = trace_buffer_lock_reserve(buffer, TRACE_POWER,
sizeof(*entry), 0, 0);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
entry->state_data = *it;
- if (!filter_check_discard(call, entry, tr->buffer, event))
- trace_buffer_unlock_commit(tr, event, 0, 0);
+ if (!filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, 0, 0);
out:
preempt_enable();
}
@@ -144,14 +150,12 @@ static void power_trace_reset(struct trace_array *tr)
static int power_trace_init(struct trace_array *tr)
{
- int cpu;
power_trace = tr;
trace_power_enabled = 1;
tracing_power_register();
- for_each_cpu(cpu, cpu_possible_mask)
- tracing_reset(tr, cpu);
+ tracing_reset_online_cpus(tr);
return 0;
}
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 9bece9687b6..687699d365a 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -155,25 +155,19 @@ int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap)
EXPORT_SYMBOL_GPL(__ftrace_vprintk);
static void *
-t_next(struct seq_file *m, void *v, loff_t *pos)
+t_start(struct seq_file *m, loff_t *pos)
{
- const char **fmt = m->private;
- const char **next = fmt;
-
- (*pos)++;
+ const char **fmt = __start___trace_bprintk_fmt + *pos;
if ((unsigned long)fmt >= (unsigned long)__stop___trace_bprintk_fmt)
return NULL;
-
- next = fmt;
- m->private = ++next;
-
return fmt;
}
-static void *t_start(struct seq_file *m, loff_t *pos)
+static void *t_next(struct seq_file *m, void * v, loff_t *pos)
{
- return t_next(m, NULL, pos);
+ (*pos)++;
+ return t_start(m, pos);
}
static int t_show(struct seq_file *m, void *v)
@@ -182,7 +176,7 @@ static int t_show(struct seq_file *m, void *v)
const char *str = *fmt;
int i;
- seq_printf(m, "0x%lx : \"", (unsigned long)fmt);
+ seq_printf(m, "0x%lx : \"", *(unsigned long *)fmt);
/*
* Tabs and new lines need to be converted.
@@ -224,15 +218,7 @@ static const struct seq_operations show_format_seq_ops = {
static int
ftrace_formats_open(struct inode *inode, struct file *file)
{
- int ret;
-
- ret = seq_open(file, &show_format_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
-
- m->private = __start___trace_bprintk_fmt;
- }
- return ret;
+ return seq_open(file, &show_format_seq_ops);
}
static const struct file_operations ftrace_formats_fops = {
diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c
index a98106dd979..5fca0f51fde 100644
--- a/kernel/trace/trace_sched_switch.c
+++ b/kernel/trace/trace_sched_switch.c
@@ -20,6 +20,35 @@ static int sched_ref;
static DEFINE_MUTEX(sched_register_mutex);
static int sched_stopped;
+
+void
+tracing_sched_switch_trace(struct trace_array *tr,
+ struct task_struct *prev,
+ struct task_struct *next,
+ unsigned long flags, int pc)
+{
+ struct ftrace_event_call *call = &event_context_switch;
+ struct ring_buffer *buffer = tr->buffer;
+ struct ring_buffer_event *event;
+ struct ctx_switch_entry *entry;
+
+ event = trace_buffer_lock_reserve(buffer, TRACE_CTX,
+ sizeof(*entry), flags, pc);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ entry->prev_pid = prev->pid;
+ entry->prev_prio = prev->prio;
+ entry->prev_state = prev->state;
+ entry->next_pid = next->pid;
+ entry->next_prio = next->prio;
+ entry->next_state = next->state;
+ entry->next_cpu = task_cpu(next);
+
+ if (!filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, flags, pc);
+}
+
static void
probe_sched_switch(struct rq *__rq, struct task_struct *prev,
struct task_struct *next)
@@ -49,6 +78,36 @@ probe_sched_switch(struct rq *__rq, struct task_struct *prev,
local_irq_restore(flags);
}
+void
+tracing_sched_wakeup_trace(struct trace_array *tr,
+ struct task_struct *wakee,
+ struct task_struct *curr,
+ unsigned long flags, int pc)
+{
+ struct ftrace_event_call *call = &event_wakeup;
+ struct ring_buffer_event *event;
+ struct ctx_switch_entry *entry;
+ struct ring_buffer *buffer = tr->buffer;
+
+ event = trace_buffer_lock_reserve(buffer, TRACE_WAKE,
+ sizeof(*entry), flags, pc);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ entry->prev_pid = curr->pid;
+ entry->prev_prio = curr->prio;
+ entry->prev_state = curr->state;
+ entry->next_pid = wakee->pid;
+ entry->next_prio = wakee->prio;
+ entry->next_state = wakee->state;
+ entry->next_cpu = task_cpu(wakee);
+
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
+ ftrace_trace_stack(tr->buffer, flags, 6, pc);
+ ftrace_trace_userstack(tr->buffer, flags, pc);
+}
+
static void
probe_sched_wakeup(struct rq *__rq, struct task_struct *wakee, int success)
{
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index eacb2722517..ad69f105a7c 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -186,11 +186,6 @@ out:
static void __wakeup_reset(struct trace_array *tr)
{
- int cpu;
-
- for_each_possible_cpu(cpu)
- tracing_reset(tr, cpu);
-
wakeup_cpu = -1;
wakeup_prio = -1;
@@ -204,6 +199,8 @@ static void wakeup_reset(struct trace_array *tr)
{
unsigned long flags;
+ tracing_reset_online_cpus(tr);
+
local_irq_save(flags);
__raw_spin_lock(&wakeup_lock);
__wakeup_reset(tr);
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 71f2edb0fd8..7179c12e4f0 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -289,6 +289,7 @@ trace_selftest_startup_function_graph(struct tracer *trace,
* to detect and recover from possible hangs
*/
tracing_reset_online_cpus(tr);
+ set_graph_array(tr);
ret = register_ftrace_graph(&trace_graph_return,
&trace_graph_entry_watchdog);
if (ret) {
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 2d7aebd71db..0f6facb050a 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -186,43 +186,33 @@ static const struct file_operations stack_max_size_fops = {
};
static void *
-t_next(struct seq_file *m, void *v, loff_t *pos)
+__next(struct seq_file *m, loff_t *pos)
{
- long i;
-
- (*pos)++;
-
- if (v == SEQ_START_TOKEN)
- i = 0;
- else {
- i = *(long *)v;
- i++;
- }
+ long n = *pos - 1;
- if (i >= max_stack_trace.nr_entries ||
- stack_dump_trace[i] == ULONG_MAX)
+ if (n >= max_stack_trace.nr_entries || stack_dump_trace[n] == ULONG_MAX)
return NULL;
- m->private = (void *)i;
-
+ m->private = (void *)n;
return &m->private;
}
-static void *t_start(struct seq_file *m, loff_t *pos)
+static void *
+t_next(struct seq_file *m, void *v, loff_t *pos)
{
- void *t = SEQ_START_TOKEN;
- loff_t l = 0;
+ (*pos)++;
+ return __next(m, pos);
+}
+static void *t_start(struct seq_file *m, loff_t *pos)
+{
local_irq_disable();
__raw_spin_lock(&max_stack_lock);
if (*pos == 0)
return SEQ_START_TOKEN;
- for (; t && l < *pos; t = t_next(m, t, &l))
- ;
-
- return t;
+ return __next(m, pos);
}
static void t_stop(struct seq_file *m, void *p)
@@ -234,15 +224,8 @@ static void t_stop(struct seq_file *m, void *p)
static int trace_lookup_stack(struct seq_file *m, long i)
{
unsigned long addr = stack_dump_trace[i];
-#ifdef CONFIG_KALLSYMS
- char str[KSYM_SYMBOL_LEN];
- sprint_symbol(str, addr);
-
- return seq_printf(m, "%s\n", str);
-#else
- return seq_printf(m, "%p\n", (void*)addr);
-#endif
+ return seq_printf(m, "%pF\n", (void *)addr);
}
static void print_disabled(struct seq_file *m)
@@ -301,17 +284,14 @@ static const struct seq_operations stack_trace_seq_ops = {
static int stack_trace_open(struct inode *inode, struct file *file)
{
- int ret;
-
- ret = seq_open(file, &stack_trace_seq_ops);
-
- return ret;
+ return seq_open(file, &stack_trace_seq_ops);
}
static const struct file_operations stack_trace_fops = {
.open = stack_trace_open,
.read = seq_read,
.llseek = seq_lseek,
+ .release = seq_release,
};
int
@@ -326,10 +306,10 @@ stack_trace_sysctl(struct ctl_table *table, int write,
ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
if (ret || !write ||
- (last_stack_tracer_enabled == stack_tracer_enabled))
+ (last_stack_tracer_enabled == !!stack_tracer_enabled))
goto out;
- last_stack_tracer_enabled = stack_tracer_enabled;
+ last_stack_tracer_enabled = !!stack_tracer_enabled;
if (stack_tracer_enabled)
register_ftrace_function(&trace_ops);
diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c
index c00643733f4..a4bb239eb98 100644
--- a/kernel/trace/trace_stat.c
+++ b/kernel/trace/trace_stat.c
@@ -49,7 +49,8 @@ static struct dentry *stat_dir;
* but it will at least advance closer to the next one
* to be released.
*/
-static struct rb_node *release_next(struct rb_node *node)
+static struct rb_node *release_next(struct tracer_stat *ts,
+ struct rb_node *node)
{
struct stat_node *snode;
struct rb_node *parent = rb_parent(node);
@@ -67,26 +68,35 @@ static struct rb_node *release_next(struct rb_node *node)
parent->rb_right = NULL;
snode = container_of(node, struct stat_node, node);
+ if (ts->stat_release)
+ ts->stat_release(snode->stat);
kfree(snode);
return parent;
}
}
-static void reset_stat_session(struct stat_session *session)
+static void __reset_stat_session(struct stat_session *session)
{
struct rb_node *node = session->stat_root.rb_node;
while (node)
- node = release_next(node);
+ node = release_next(session->ts, node);
session->stat_root = RB_ROOT;
}
+static void reset_stat_session(struct stat_session *session)
+{
+ mutex_lock(&session->stat_mutex);
+ __reset_stat_session(session);
+ mutex_unlock(&session->stat_mutex);
+}
+
static void destroy_session(struct stat_session *session)
{
debugfs_remove(session->file);
- reset_stat_session(session);
+ __reset_stat_session(session);
mutex_destroy(&session->stat_mutex);
kfree(session);
}
@@ -150,7 +160,7 @@ static int stat_seq_init(struct stat_session *session)
int i;
mutex_lock(&session->stat_mutex);
- reset_stat_session(session);
+ __reset_stat_session(session);
if (!ts->stat_cmp)
ts->stat_cmp = dummy_cmp;
@@ -183,7 +193,7 @@ exit:
return ret;
exit_free_rbtree:
- reset_stat_session(session);
+ __reset_stat_session(session);
mutex_unlock(&session->stat_mutex);
return ret;
}
@@ -193,23 +203,23 @@ static void *stat_seq_start(struct seq_file *s, loff_t *pos)
{
struct stat_session *session = s->private;
struct rb_node *node;
+ int n = *pos;
int i;
/* Prevent from tracer switch or rbtree modification */
mutex_lock(&session->stat_mutex);
/* If we are in the beginning of the file, print the headers */
- if (!*pos && session->ts->stat_headers) {
- (*pos)++;
- return SEQ_START_TOKEN;
+ if (session->ts->stat_headers) {
+ if (n == 0)
+ return SEQ_START_TOKEN;
+ n--;
}
node = rb_first(&session->stat_root);
- for (i = 0; node && i < *pos; i++)
+ for (i = 0; node && i < n; i++)
node = rb_next(node);
- (*pos)++;
-
return node;
}
@@ -254,16 +264,21 @@ static const struct seq_operations trace_stat_seq_ops = {
static int tracing_stat_open(struct inode *inode, struct file *file)
{
int ret;
-
+ struct seq_file *m;
struct stat_session *session = inode->i_private;
+ ret = stat_seq_init(session);
+ if (ret)
+ return ret;
+
ret = seq_open(file, &trace_stat_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = session;
- ret = stat_seq_init(session);
+ if (ret) {
+ reset_stat_session(session);
+ return ret;
}
+ m = file->private_data;
+ m->private = session;
return ret;
}
@@ -274,11 +289,9 @@ static int tracing_stat_release(struct inode *i, struct file *f)
{
struct stat_session *session = i->i_private;
- mutex_lock(&session->stat_mutex);
reset_stat_session(session);
- mutex_unlock(&session->stat_mutex);
- return 0;
+ return seq_release(i, f);
}
static const struct file_operations tracing_stat_fops = {
diff --git a/kernel/trace/trace_stat.h b/kernel/trace/trace_stat.h
index f3546a2cd82..8f03914b9a6 100644
--- a/kernel/trace/trace_stat.h
+++ b/kernel/trace/trace_stat.h
@@ -18,6 +18,8 @@ struct tracer_stat {
int (*stat_cmp)(void *p1, void *p2);
/* Print a stat entry */
int (*stat_show)(struct seq_file *s, void *p);
+ /* Release an entry */
+ void (*stat_release)(void *stat);
/* Print the headers of your stat entries */
int (*stat_headers)(struct seq_file *s);
};
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 5e579645ac8..8712ce3c6a0 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -1,30 +1,18 @@
#include <trace/syscall.h>
+#include <trace/events/syscalls.h>
#include <linux/kernel.h>
+#include <linux/ftrace.h>
+#include <linux/perf_counter.h>
#include <asm/syscall.h>
#include "trace_output.h"
#include "trace.h"
-/* Keep a counter of the syscall tracing users */
-static int refcount;
-
-/* Prevent from races on thread flags toggling */
static DEFINE_MUTEX(syscall_trace_lock);
-
-/* Option to display the parameters types */
-enum {
- TRACE_SYSCALLS_OPT_TYPES = 0x1,
-};
-
-static struct tracer_opt syscalls_opts[] = {
- { TRACER_OPT(syscall_arg_type, TRACE_SYSCALLS_OPT_TYPES) },
- { }
-};
-
-static struct tracer_flags syscalls_flags = {
- .val = 0, /* By default: no parameters types */
- .opts = syscalls_opts
-};
+static int sys_refcount_enter;
+static int sys_refcount_exit;
+static DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
+static DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
enum print_line_t
print_syscall_enter(struct trace_iterator *iter, int flags)
@@ -35,35 +23,46 @@ print_syscall_enter(struct trace_iterator *iter, int flags)
struct syscall_metadata *entry;
int i, ret, syscall;
- trace_assign_type(trace, ent);
-
+ trace = (typeof(trace))ent;
syscall = trace->nr;
-
entry = syscall_nr_to_meta(syscall);
+
if (!entry)
goto end;
+ if (entry->enter_id != ent->type) {
+ WARN_ON_ONCE(1);
+ goto end;
+ }
+
ret = trace_seq_printf(s, "%s(", entry->name);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
for (i = 0; i < entry->nb_args; i++) {
/* parameter types */
- if (syscalls_flags.val & TRACE_SYSCALLS_OPT_TYPES) {
+ if (trace_flags & TRACE_ITER_VERBOSE) {
ret = trace_seq_printf(s, "%s ", entry->types[i]);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
/* parameter values */
- ret = trace_seq_printf(s, "%s: %lx%s ", entry->args[i],
+ ret = trace_seq_printf(s, "%s: %lx%s", entry->args[i],
trace->args[i],
- i == entry->nb_args - 1 ? ")" : ",");
+ i == entry->nb_args - 1 ? "" : ", ");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
+ ret = trace_seq_putc(s, ')');
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
end:
- trace_seq_printf(s, "\n");
+ ret = trace_seq_putc(s, '\n');
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
return TRACE_TYPE_HANDLED;
}
@@ -77,16 +76,20 @@ print_syscall_exit(struct trace_iterator *iter, int flags)
struct syscall_metadata *entry;
int ret;
- trace_assign_type(trace, ent);
-
+ trace = (typeof(trace))ent;
syscall = trace->nr;
-
entry = syscall_nr_to_meta(syscall);
+
if (!entry) {
trace_seq_printf(s, "\n");
return TRACE_TYPE_HANDLED;
}
+ if (entry->exit_id != ent->type) {
+ WARN_ON_ONCE(1);
+ return TRACE_TYPE_UNHANDLED;
+ }
+
ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,
trace->ret);
if (!ret)
@@ -95,62 +98,140 @@ print_syscall_exit(struct trace_iterator *iter, int flags)
return TRACE_TYPE_HANDLED;
}
-void start_ftrace_syscalls(void)
+extern char *__bad_type_size(void);
+
+#define SYSCALL_FIELD(type, name) \
+ sizeof(type) != sizeof(trace.name) ? \
+ __bad_type_size() : \
+ #type, #name, offsetof(typeof(trace), name), sizeof(trace.name)
+
+int syscall_enter_format(struct ftrace_event_call *call, struct trace_seq *s)
{
- unsigned long flags;
- struct task_struct *g, *t;
+ int i;
+ int nr;
+ int ret;
+ struct syscall_metadata *entry;
+ struct syscall_trace_enter trace;
+ int offset = offsetof(struct syscall_trace_enter, args);
- mutex_lock(&syscall_trace_lock);
+ nr = syscall_name_to_nr(call->data);
+ entry = syscall_nr_to_meta(nr);
- /* Don't enable the flag on the tasks twice */
- if (++refcount != 1)
- goto unlock;
+ if (!entry)
+ return 0;
- arch_init_ftrace_syscalls();
- read_lock_irqsave(&tasklist_lock, flags);
+ ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
+ SYSCALL_FIELD(int, nr));
+ if (!ret)
+ return 0;
- do_each_thread(g, t) {
- set_tsk_thread_flag(t, TIF_SYSCALL_FTRACE);
- } while_each_thread(g, t);
+ for (i = 0; i < entry->nb_args; i++) {
+ ret = trace_seq_printf(s, "\tfield:%s %s;", entry->types[i],
+ entry->args[i]);
+ if (!ret)
+ return 0;
+ ret = trace_seq_printf(s, "\toffset:%d;\tsize:%zu;\n", offset,
+ sizeof(unsigned long));
+ if (!ret)
+ return 0;
+ offset += sizeof(unsigned long);
+ }
- read_unlock_irqrestore(&tasklist_lock, flags);
+ trace_seq_puts(s, "\nprint fmt: \"");
+ for (i = 0; i < entry->nb_args; i++) {
+ ret = trace_seq_printf(s, "%s: 0x%%0%zulx%s", entry->args[i],
+ sizeof(unsigned long),
+ i == entry->nb_args - 1 ? "" : ", ");
+ if (!ret)
+ return 0;
+ }
+ trace_seq_putc(s, '"');
-unlock:
- mutex_unlock(&syscall_trace_lock);
+ for (i = 0; i < entry->nb_args; i++) {
+ ret = trace_seq_printf(s, ", ((unsigned long)(REC->%s))",
+ entry->args[i]);
+ if (!ret)
+ return 0;
+ }
+
+ return trace_seq_putc(s, '\n');
}
-void stop_ftrace_syscalls(void)
+int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
{
- unsigned long flags;
- struct task_struct *g, *t;
+ int ret;
+ struct syscall_trace_exit trace;
- mutex_lock(&syscall_trace_lock);
+ ret = trace_seq_printf(s,
+ "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
+ "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
+ SYSCALL_FIELD(int, nr),
+ SYSCALL_FIELD(unsigned long, ret));
+ if (!ret)
+ return 0;
- /* There are perhaps still some users */
- if (--refcount)
- goto unlock;
+ return trace_seq_printf(s, "\nprint fmt: \"0x%%lx\", REC->ret\n");
+}
- read_lock_irqsave(&tasklist_lock, flags);
+int syscall_enter_define_fields(struct ftrace_event_call *call)
+{
+ struct syscall_trace_enter trace;
+ struct syscall_metadata *meta;
+ int ret;
+ int nr;
+ int i;
+ int offset = offsetof(typeof(trace), args);
+
+ nr = syscall_name_to_nr(call->data);
+ meta = syscall_nr_to_meta(nr);
+
+ if (!meta)
+ return 0;
+
+ ret = trace_define_common_fields(call);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < meta->nb_args; i++) {
+ ret = trace_define_field(call, meta->types[i],
+ meta->args[i], offset,
+ sizeof(unsigned long), 0,
+ FILTER_OTHER);
+ offset += sizeof(unsigned long);
+ }
- do_each_thread(g, t) {
- clear_tsk_thread_flag(t, TIF_SYSCALL_FTRACE);
- } while_each_thread(g, t);
+ return ret;
+}
- read_unlock_irqrestore(&tasklist_lock, flags);
+int syscall_exit_define_fields(struct ftrace_event_call *call)
+{
+ struct syscall_trace_exit trace;
+ int ret;
-unlock:
- mutex_unlock(&syscall_trace_lock);
+ ret = trace_define_common_fields(call);
+ if (ret)
+ return ret;
+
+ ret = trace_define_field(call, SYSCALL_FIELD(unsigned long, ret), 0,
+ FILTER_OTHER);
+
+ return ret;
}
-void ftrace_syscall_enter(struct pt_regs *regs)
+void ftrace_syscall_enter(struct pt_regs *regs, long id)
{
struct syscall_trace_enter *entry;
struct syscall_metadata *sys_data;
struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
int size;
int syscall_nr;
syscall_nr = syscall_get_nr(current, regs);
+ if (syscall_nr < 0)
+ return;
+ if (!test_bit(syscall_nr, enabled_enter_syscalls))
+ return;
sys_data = syscall_nr_to_meta(syscall_nr);
if (!sys_data)
@@ -158,8 +239,8 @@ void ftrace_syscall_enter(struct pt_regs *regs)
size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
- event = trace_current_buffer_lock_reserve(TRACE_SYSCALL_ENTER, size,
- 0, 0);
+ event = trace_current_buffer_lock_reserve(&buffer, sys_data->enter_id,
+ size, 0, 0);
if (!event)
return;
@@ -167,24 +248,30 @@ void ftrace_syscall_enter(struct pt_regs *regs)
entry->nr = syscall_nr;
syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args);
- trace_current_buffer_unlock_commit(event, 0, 0);
- trace_wake_up();
+ if (!filter_current_check_discard(buffer, sys_data->enter_event,
+ entry, event))
+ trace_current_buffer_unlock_commit(buffer, event, 0, 0);
}
-void ftrace_syscall_exit(struct pt_regs *regs)
+void ftrace_syscall_exit(struct pt_regs *regs, long ret)
{
struct syscall_trace_exit *entry;
struct syscall_metadata *sys_data;
struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
int syscall_nr;
syscall_nr = syscall_get_nr(current, regs);
+ if (syscall_nr < 0)
+ return;
+ if (!test_bit(syscall_nr, enabled_exit_syscalls))
+ return;
sys_data = syscall_nr_to_meta(syscall_nr);
if (!sys_data)
return;
- event = trace_current_buffer_lock_reserve(TRACE_SYSCALL_EXIT,
+ event = trace_current_buffer_lock_reserve(&buffer, sys_data->exit_id,
sizeof(*entry), 0, 0);
if (!event)
return;
@@ -193,58 +280,244 @@ void ftrace_syscall_exit(struct pt_regs *regs)
entry->nr = syscall_nr;
entry->ret = syscall_get_return_value(current, regs);
- trace_current_buffer_unlock_commit(event, 0, 0);
- trace_wake_up();
+ if (!filter_current_check_discard(buffer, sys_data->exit_event,
+ entry, event))
+ trace_current_buffer_unlock_commit(buffer, event, 0, 0);
}
-static int init_syscall_tracer(struct trace_array *tr)
+int reg_event_syscall_enter(void *ptr)
{
- start_ftrace_syscalls();
+ int ret = 0;
+ int num;
+ char *name;
+
+ name = (char *)ptr;
+ num = syscall_name_to_nr(name);
+ if (num < 0 || num >= NR_syscalls)
+ return -ENOSYS;
+ mutex_lock(&syscall_trace_lock);
+ if (!sys_refcount_enter)
+ ret = register_trace_sys_enter(ftrace_syscall_enter);
+ if (ret) {
+ pr_info("event trace: Could not activate"
+ "syscall entry trace point");
+ } else {
+ set_bit(num, enabled_enter_syscalls);
+ sys_refcount_enter++;
+ }
+ mutex_unlock(&syscall_trace_lock);
+ return ret;
+}
+
+void unreg_event_syscall_enter(void *ptr)
+{
+ int num;
+ char *name;
- return 0;
+ name = (char *)ptr;
+ num = syscall_name_to_nr(name);
+ if (num < 0 || num >= NR_syscalls)
+ return;
+ mutex_lock(&syscall_trace_lock);
+ sys_refcount_enter--;
+ clear_bit(num, enabled_enter_syscalls);
+ if (!sys_refcount_enter)
+ unregister_trace_sys_enter(ftrace_syscall_enter);
+ mutex_unlock(&syscall_trace_lock);
}
-static void reset_syscall_tracer(struct trace_array *tr)
+int reg_event_syscall_exit(void *ptr)
{
- stop_ftrace_syscalls();
- tracing_reset_online_cpus(tr);
+ int ret = 0;
+ int num;
+ char *name;
+
+ name = (char *)ptr;
+ num = syscall_name_to_nr(name);
+ if (num < 0 || num >= NR_syscalls)
+ return -ENOSYS;
+ mutex_lock(&syscall_trace_lock);
+ if (!sys_refcount_exit)
+ ret = register_trace_sys_exit(ftrace_syscall_exit);
+ if (ret) {
+ pr_info("event trace: Could not activate"
+ "syscall exit trace point");
+ } else {
+ set_bit(num, enabled_exit_syscalls);
+ sys_refcount_exit++;
+ }
+ mutex_unlock(&syscall_trace_lock);
+ return ret;
}
-static struct trace_event syscall_enter_event = {
- .type = TRACE_SYSCALL_ENTER,
- .trace = print_syscall_enter,
-};
+void unreg_event_syscall_exit(void *ptr)
+{
+ int num;
+ char *name;
+
+ name = (char *)ptr;
+ num = syscall_name_to_nr(name);
+ if (num < 0 || num >= NR_syscalls)
+ return;
+ mutex_lock(&syscall_trace_lock);
+ sys_refcount_exit--;
+ clear_bit(num, enabled_exit_syscalls);
+ if (!sys_refcount_exit)
+ unregister_trace_sys_exit(ftrace_syscall_exit);
+ mutex_unlock(&syscall_trace_lock);
+}
-static struct trace_event syscall_exit_event = {
- .type = TRACE_SYSCALL_EXIT,
- .trace = print_syscall_exit,
+struct trace_event event_syscall_enter = {
+ .trace = print_syscall_enter,
};
-static struct tracer syscall_tracer __read_mostly = {
- .name = "syscall",
- .init = init_syscall_tracer,
- .reset = reset_syscall_tracer,
- .flags = &syscalls_flags,
+struct trace_event event_syscall_exit = {
+ .trace = print_syscall_exit,
};
-__init int register_ftrace_syscalls(void)
+#ifdef CONFIG_EVENT_PROFILE
+
+static DECLARE_BITMAP(enabled_prof_enter_syscalls, NR_syscalls);
+static DECLARE_BITMAP(enabled_prof_exit_syscalls, NR_syscalls);
+static int sys_prof_refcount_enter;
+static int sys_prof_refcount_exit;
+
+static void prof_syscall_enter(struct pt_regs *regs, long id)
{
- int ret;
+ struct syscall_trace_enter *rec;
+ struct syscall_metadata *sys_data;
+ int syscall_nr;
+ int size;
- ret = register_ftrace_event(&syscall_enter_event);
- if (!ret) {
- printk(KERN_WARNING "event %d failed to register\n",
- syscall_enter_event.type);
- WARN_ON_ONCE(1);
+ syscall_nr = syscall_get_nr(current, regs);
+ if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
+ return;
+
+ sys_data = syscall_nr_to_meta(syscall_nr);
+ if (!sys_data)
+ return;
+
+ /* get the size after alignment with the u32 buffer size field */
+ size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);
+ size = ALIGN(size + sizeof(u32), sizeof(u64));
+ size -= sizeof(u32);
+
+ do {
+ char raw_data[size];
+
+ /* zero the dead bytes from align to not leak stack to user */
+ *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+
+ rec = (struct syscall_trace_enter *) raw_data;
+ tracing_generic_entry_update(&rec->ent, 0, 0);
+ rec->ent.type = sys_data->enter_id;
+ rec->nr = syscall_nr;
+ syscall_get_arguments(current, regs, 0, sys_data->nb_args,
+ (unsigned long *)&rec->args);
+ perf_tpcounter_event(sys_data->enter_id, 0, 1, rec, size);
+ } while(0);
+}
+
+int reg_prof_syscall_enter(char *name)
+{
+ int ret = 0;
+ int num;
+
+ num = syscall_name_to_nr(name);
+ if (num < 0 || num >= NR_syscalls)
+ return -ENOSYS;
+
+ mutex_lock(&syscall_trace_lock);
+ if (!sys_prof_refcount_enter)
+ ret = register_trace_sys_enter(prof_syscall_enter);
+ if (ret) {
+ pr_info("event trace: Could not activate"
+ "syscall entry trace point");
+ } else {
+ set_bit(num, enabled_prof_enter_syscalls);
+ sys_prof_refcount_enter++;
}
+ mutex_unlock(&syscall_trace_lock);
+ return ret;
+}
- ret = register_ftrace_event(&syscall_exit_event);
- if (!ret) {
- printk(KERN_WARNING "event %d failed to register\n",
- syscall_exit_event.type);
- WARN_ON_ONCE(1);
+void unreg_prof_syscall_enter(char *name)
+{
+ int num;
+
+ num = syscall_name_to_nr(name);
+ if (num < 0 || num >= NR_syscalls)
+ return;
+
+ mutex_lock(&syscall_trace_lock);
+ sys_prof_refcount_enter--;
+ clear_bit(num, enabled_prof_enter_syscalls);
+ if (!sys_prof_refcount_enter)
+ unregister_trace_sys_enter(prof_syscall_enter);
+ mutex_unlock(&syscall_trace_lock);
+}
+
+static void prof_syscall_exit(struct pt_regs *regs, long ret)
+{
+ struct syscall_metadata *sys_data;
+ struct syscall_trace_exit rec;
+ int syscall_nr;
+
+ syscall_nr = syscall_get_nr(current, regs);
+ if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
+ return;
+
+ sys_data = syscall_nr_to_meta(syscall_nr);
+ if (!sys_data)
+ return;
+
+ tracing_generic_entry_update(&rec.ent, 0, 0);
+ rec.ent.type = sys_data->exit_id;
+ rec.nr = syscall_nr;
+ rec.ret = syscall_get_return_value(current, regs);
+
+ perf_tpcounter_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec));
+}
+
+int reg_prof_syscall_exit(char *name)
+{
+ int ret = 0;
+ int num;
+
+ num = syscall_name_to_nr(name);
+ if (num < 0 || num >= NR_syscalls)
+ return -ENOSYS;
+
+ mutex_lock(&syscall_trace_lock);
+ if (!sys_prof_refcount_exit)
+ ret = register_trace_sys_exit(prof_syscall_exit);
+ if (ret) {
+ pr_info("event trace: Could not activate"
+ "syscall entry trace point");
+ } else {
+ set_bit(num, enabled_prof_exit_syscalls);
+ sys_prof_refcount_exit++;
}
+ mutex_unlock(&syscall_trace_lock);
+ return ret;
+}
- return register_tracer(&syscall_tracer);
+void unreg_prof_syscall_exit(char *name)
+{
+ int num;
+
+ num = syscall_name_to_nr(name);
+ if (num < 0 || num >= NR_syscalls)
+ return;
+
+ mutex_lock(&syscall_trace_lock);
+ sys_prof_refcount_exit--;
+ clear_bit(num, enabled_prof_exit_syscalls);
+ if (!sys_prof_refcount_exit)
+ unregister_trace_sys_exit(prof_syscall_exit);
+ mutex_unlock(&syscall_trace_lock);
}
-device_initcall(register_ftrace_syscalls);
+
+#endif
+
+
diff --git a/kernel/trace/trace_workqueue.c b/kernel/trace/trace_workqueue.c
index 97fcea4acce..40cafb07dff 100644
--- a/kernel/trace/trace_workqueue.c
+++ b/kernel/trace/trace_workqueue.c
@@ -9,6 +9,7 @@
#include <trace/events/workqueue.h>
#include <linux/list.h>
#include <linux/percpu.h>
+#include <linux/kref.h>
#include "trace_stat.h"
#include "trace.h"
@@ -16,6 +17,7 @@
/* A cpu workqueue thread */
struct cpu_workqueue_stats {
struct list_head list;
+ struct kref kref;
int cpu;
pid_t pid;
/* Can be inserted from interrupt or user context, need to be atomic */
@@ -39,6 +41,11 @@ struct workqueue_global_stats {
static DEFINE_PER_CPU(struct workqueue_global_stats, all_workqueue_stat);
#define workqueue_cpu_stat(cpu) (&per_cpu(all_workqueue_stat, cpu))
+static void cpu_workqueue_stat_free(struct kref *kref)
+{
+ kfree(container_of(kref, struct cpu_workqueue_stats, kref));
+}
+
/* Insertion of a work */
static void
probe_workqueue_insertion(struct task_struct *wq_thread,
@@ -96,8 +103,8 @@ static void probe_workqueue_creation(struct task_struct *wq_thread, int cpu)
return;
}
INIT_LIST_HEAD(&cws->list);
+ kref_init(&cws->kref);
cws->cpu = cpu;
-
cws->pid = wq_thread->pid;
spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags);
@@ -118,7 +125,7 @@ static void probe_workqueue_destruction(struct task_struct *wq_thread)
list) {
if (node->pid == wq_thread->pid) {
list_del(&node->list);
- kfree(node);
+ kref_put(&node->kref, cpu_workqueue_stat_free);
goto found;
}
}
@@ -137,9 +144,11 @@ static struct cpu_workqueue_stats *workqueue_stat_start_cpu(int cpu)
spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags);
- if (!list_empty(&workqueue_cpu_stat(cpu)->list))
+ if (!list_empty(&workqueue_cpu_stat(cpu)->list)) {
ret = list_entry(workqueue_cpu_stat(cpu)->list.next,
struct cpu_workqueue_stats, list);
+ kref_get(&ret->kref);
+ }
spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags);
@@ -162,9 +171,9 @@ static void *workqueue_stat_start(struct tracer_stat *trace)
static void *workqueue_stat_next(void *prev, int idx)
{
struct cpu_workqueue_stats *prev_cws = prev;
+ struct cpu_workqueue_stats *ret;
int cpu = prev_cws->cpu;
unsigned long flags;
- void *ret = NULL;
spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags);
if (list_is_last(&prev_cws->list, &workqueue_cpu_stat(cpu)->list)) {
@@ -175,11 +184,14 @@ static void *workqueue_stat_next(void *prev, int idx)
return NULL;
} while (!(ret = workqueue_stat_start_cpu(cpu)));
return ret;
+ } else {
+ ret = list_entry(prev_cws->list.next,
+ struct cpu_workqueue_stats, list);
+ kref_get(&ret->kref);
}
spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags);
- return list_entry(prev_cws->list.next, struct cpu_workqueue_stats,
- list);
+ return ret;
}
static int workqueue_stat_show(struct seq_file *s, void *p)
@@ -203,6 +215,13 @@ static int workqueue_stat_show(struct seq_file *s, void *p)
return 0;
}
+static void workqueue_stat_release(void *stat)
+{
+ struct cpu_workqueue_stats *node = stat;
+
+ kref_put(&node->kref, cpu_workqueue_stat_free);
+}
+
static int workqueue_stat_headers(struct seq_file *s)
{
seq_printf(s, "# CPU INSERTED EXECUTED NAME\n");
@@ -215,6 +234,7 @@ struct tracer_stat workqueue_stats __read_mostly = {
.stat_start = workqueue_stat_start,
.stat_next = workqueue_stat_next,
.stat_show = workqueue_stat_show,
+ .stat_release = workqueue_stat_release,
.stat_headers = workqueue_stat_headers
};