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Diffstat (limited to 'kernel/trace/ftrace.c')
-rw-r--r--kernel/trace/ftrace.c161
1 files changed, 123 insertions, 38 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 03cf44ac54d3..22fa55696760 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3307,7 +3307,11 @@ void unregister_ftrace_function_probe_all(char *glob)
static LIST_HEAD(ftrace_commands);
static DEFINE_MUTEX(ftrace_cmd_mutex);
-int register_ftrace_command(struct ftrace_func_command *cmd)
+/*
+ * Currently we only register ftrace commands from __init, so mark this
+ * __init too.
+ */
+__init int register_ftrace_command(struct ftrace_func_command *cmd)
{
struct ftrace_func_command *p;
int ret = 0;
@@ -3326,7 +3330,11 @@ int register_ftrace_command(struct ftrace_func_command *cmd)
return ret;
}
-int unregister_ftrace_command(struct ftrace_func_command *cmd)
+/*
+ * Currently we only unregister ftrace commands from __init, so mark
+ * this __init too.
+ */
+__init int unregister_ftrace_command(struct ftrace_func_command *cmd)
{
struct ftrace_func_command *p, *n;
int ret = -ENODEV;
@@ -3641,7 +3649,7 @@ __setup("ftrace_filter=", set_ftrace_filter);
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata;
-static int ftrace_set_func(unsigned long *array, int *idx, char *buffer);
+static int ftrace_set_func(unsigned long *array, int *idx, int size, char *buffer);
static int __init set_graph_function(char *str)
{
@@ -3659,7 +3667,7 @@ static void __init set_ftrace_early_graph(char *buf)
func = strsep(&buf, ",");
/* we allow only one expression at a time */
ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
- func);
+ FTRACE_GRAPH_MAX_FUNCS, func);
if (ret)
printk(KERN_DEBUG "ftrace: function %s not "
"traceable\n", func);
@@ -3776,15 +3784,25 @@ static const struct file_operations ftrace_notrace_fops = {
static DEFINE_MUTEX(graph_lock);
int ftrace_graph_count;
-int ftrace_graph_filter_enabled;
+int ftrace_graph_notrace_count;
unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
+unsigned long ftrace_graph_notrace_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
+
+struct ftrace_graph_data {
+ unsigned long *table;
+ size_t size;
+ int *count;
+ const struct seq_operations *seq_ops;
+};
static void *
__g_next(struct seq_file *m, loff_t *pos)
{
- if (*pos >= ftrace_graph_count)
+ struct ftrace_graph_data *fgd = m->private;
+
+ if (*pos >= *fgd->count)
return NULL;
- return &ftrace_graph_funcs[*pos];
+ return &fgd->table[*pos];
}
static void *
@@ -3796,10 +3814,12 @@ g_next(struct seq_file *m, void *v, loff_t *pos)
static void *g_start(struct seq_file *m, loff_t *pos)
{
+ struct ftrace_graph_data *fgd = m->private;
+
mutex_lock(&graph_lock);
/* Nothing, tell g_show to print all functions are enabled */
- if (!ftrace_graph_filter_enabled && !*pos)
+ if (!*fgd->count && !*pos)
return (void *)1;
return __g_next(m, pos);
@@ -3835,38 +3855,88 @@ static const struct seq_operations ftrace_graph_seq_ops = {
};
static int
-ftrace_graph_open(struct inode *inode, struct file *file)
+__ftrace_graph_open(struct inode *inode, struct file *file,
+ struct ftrace_graph_data *fgd)
{
int ret = 0;
- if (unlikely(ftrace_disabled))
- return -ENODEV;
-
mutex_lock(&graph_lock);
if ((file->f_mode & FMODE_WRITE) &&
(file->f_flags & O_TRUNC)) {
- ftrace_graph_filter_enabled = 0;
- ftrace_graph_count = 0;
- memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs));
+ *fgd->count = 0;
+ memset(fgd->table, 0, fgd->size * sizeof(*fgd->table));
}
mutex_unlock(&graph_lock);
- if (file->f_mode & FMODE_READ)
- ret = seq_open(file, &ftrace_graph_seq_ops);
+ if (file->f_mode & FMODE_READ) {
+ ret = seq_open(file, fgd->seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = fgd;
+ }
+ } else
+ file->private_data = fgd;
return ret;
}
static int
+ftrace_graph_open(struct inode *inode, struct file *file)
+{
+ struct ftrace_graph_data *fgd;
+
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ fgd = kmalloc(sizeof(*fgd), GFP_KERNEL);
+ if (fgd == NULL)
+ return -ENOMEM;
+
+ fgd->table = ftrace_graph_funcs;
+ fgd->size = FTRACE_GRAPH_MAX_FUNCS;
+ fgd->count = &ftrace_graph_count;
+ fgd->seq_ops = &ftrace_graph_seq_ops;
+
+ return __ftrace_graph_open(inode, file, fgd);
+}
+
+static int
+ftrace_graph_notrace_open(struct inode *inode, struct file *file)
+{
+ struct ftrace_graph_data *fgd;
+
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ fgd = kmalloc(sizeof(*fgd), GFP_KERNEL);
+ if (fgd == NULL)
+ return -ENOMEM;
+
+ fgd->table = ftrace_graph_notrace_funcs;
+ fgd->size = FTRACE_GRAPH_MAX_FUNCS;
+ fgd->count = &ftrace_graph_notrace_count;
+ fgd->seq_ops = &ftrace_graph_seq_ops;
+
+ return __ftrace_graph_open(inode, file, fgd);
+}
+
+static int
ftrace_graph_release(struct inode *inode, struct file *file)
{
- if (file->f_mode & FMODE_READ)
+ if (file->f_mode & FMODE_READ) {
+ struct seq_file *m = file->private_data;
+
+ kfree(m->private);
seq_release(inode, file);
+ } else {
+ kfree(file->private_data);
+ }
+
return 0;
}
static int
-ftrace_set_func(unsigned long *array, int *idx, char *buffer)
+ftrace_set_func(unsigned long *array, int *idx, int size, char *buffer)
{
struct dyn_ftrace *rec;
struct ftrace_page *pg;
@@ -3879,7 +3949,7 @@ ftrace_set_func(unsigned long *array, int *idx, char *buffer)
/* decode regex */
type = filter_parse_regex(buffer, strlen(buffer), &search, &not);
- if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS)
+ if (!not && *idx >= size)
return -EBUSY;
search_len = strlen(search);
@@ -3907,7 +3977,7 @@ ftrace_set_func(unsigned long *array, int *idx, char *buffer)
fail = 0;
if (!exists) {
array[(*idx)++] = rec->ip;
- if (*idx >= FTRACE_GRAPH_MAX_FUNCS)
+ if (*idx >= size)
goto out;
}
} else {
@@ -3925,8 +3995,6 @@ out:
if (fail)
return -EINVAL;
- ftrace_graph_filter_enabled = !!(*idx);
-
return 0;
}
@@ -3935,36 +4003,33 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_parser parser;
- ssize_t read, ret;
+ ssize_t read, ret = 0;
+ struct ftrace_graph_data *fgd = file->private_data;
if (!cnt)
return 0;
- mutex_lock(&graph_lock);
-
- if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
- ret = -ENOMEM;
- goto out_unlock;
- }
+ if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX))
+ return -ENOMEM;
read = trace_get_user(&parser, ubuf, cnt, ppos);
if (read >= 0 && trace_parser_loaded((&parser))) {
parser.buffer[parser.idx] = 0;
+ mutex_lock(&graph_lock);
+
/* we allow only one expression at a time */
- ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
- parser.buffer);
- if (ret)
- goto out_free;
+ ret = ftrace_set_func(fgd->table, fgd->count, fgd->size,
+ parser.buffer);
+
+ mutex_unlock(&graph_lock);
}
- ret = read;
+ if (!ret)
+ ret = read;
-out_free:
trace_parser_put(&parser);
-out_unlock:
- mutex_unlock(&graph_lock);
return ret;
}
@@ -3976,6 +4041,14 @@ static const struct file_operations ftrace_graph_fops = {
.llseek = ftrace_filter_lseek,
.release = ftrace_graph_release,
};
+
+static const struct file_operations ftrace_graph_notrace_fops = {
+ .open = ftrace_graph_notrace_open,
+ .read = seq_read,
+ .write = ftrace_graph_write,
+ .llseek = ftrace_filter_lseek,
+ .release = ftrace_graph_release,
+};
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
@@ -3997,6 +4070,9 @@ static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
trace_create_file("set_graph_function", 0444, d_tracer,
NULL,
&ftrace_graph_fops);
+ trace_create_file("set_graph_notrace", 0444, d_tracer,
+ NULL,
+ &ftrace_graph_notrace_fops);
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
return 0;
@@ -4320,12 +4396,21 @@ ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip,
*/
preempt_disable_notrace();
trace_recursion_set(TRACE_CONTROL_BIT);
+
+ /*
+ * Control funcs (perf) uses RCU. Only trace if
+ * RCU is currently active.
+ */
+ if (!rcu_is_watching())
+ goto out;
+
do_for_each_ftrace_op(op, ftrace_control_list) {
if (!(op->flags & FTRACE_OPS_FL_STUB) &&
!ftrace_function_local_disabled(op) &&
ftrace_ops_test(op, ip, regs))
op->func(ip, parent_ip, op, regs);
} while_for_each_ftrace_op(op);
+ out:
trace_recursion_clear(TRACE_CONTROL_BIT);
preempt_enable_notrace();
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-23 08:38:56 +0000