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authorLinus Torvalds <torvalds@linux-foundation.org>2013-07-02 16:15:23 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-07-02 16:15:23 -0700
commitf0bb4c0ab064a8aeeffbda1cee380151a594eaab (patch)
tree14d55a89c5db455aa10ff9a96ca14c474a9c4d55 /kernel
parenta4883ef6af5e513a1e8c2ab9aab721604aa3a4f5 (diff)
parent983433b5812c5cf33a9008fa38c6f9b407fedb76 (diff)
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar: "Kernel improvements: - watchdog driver improvements by Li Zefan - Power7 CPI stack events related improvements by Sukadev Bhattiprolu - event multiplexing via hrtimers and other improvements by Stephane Eranian - kernel stack use optimization by Andrew Hunter - AMD IOMMU uncore PMU support by Suravee Suthikulpanit - NMI handling rate-limits by Dave Hansen - various hw_breakpoint fixes by Oleg Nesterov - hw_breakpoint overflow period sampling and related signal handling fixes by Jiri Olsa - Intel Haswell PMU support by Andi Kleen Tooling improvements: - Reset SIGTERM handler in workload child process, fix from David Ahern. - Makefile reorganization, prep work for Kconfig patches, from Jiri Olsa. - Add automated make test suite, from Jiri Olsa. - Add --percent-limit option to 'top' and 'report', from Namhyung Kim. - Sorting improvements, from Namhyung Kim. - Expand definition of sysfs format attribute, from Michael Ellerman. Tooling fixes: - 'perf tests' fixes from Jiri Olsa. - Make Power7 CPI stack events available in sysfs, from Sukadev Bhattiprolu. - Handle death by SIGTERM in 'perf record', fix from David Ahern. - Fix printing of perf_event_paranoid message, from David Ahern. - Handle realloc failures in 'perf kvm', from David Ahern. - Fix divide by 0 in variance, from David Ahern. - Save parent pid in thread struct, from David Ahern. - Handle JITed code in shared memory, from Andi Kleen. - Fixes for 'perf diff', from Jiri Olsa. - Remove some unused struct members, from Jiri Olsa. - Add missing liblk.a dependency for python/perf.so, fix from Jiri Olsa. - Respect CROSS_COMPILE in liblk.a, from Rabin Vincent. - No need to do locking when adding hists in perf report, only 'top' needs that, from Namhyung Kim. - Fix alignment of symbol column in in the hists browser (top, report) when -v is given, from NAmhyung Kim. - Fix 'perf top' -E option behavior, from Namhyung Kim. - Fix bug in isupper() and islower(), from Sukadev Bhattiprolu. - Fix compile errors in bp_signal 'perf test', from Sukadev Bhattiprolu. ... and more things" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (102 commits) perf/x86: Disable PEBS-LL in intel_pmu_pebs_disable() perf/x86: Fix shared register mutual exclusion enforcement perf/x86/intel: Support full width counting x86: Add NMI duration tracepoints perf: Drop sample rate when sampling is too slow x86: Warn when NMI handlers take large amounts of time hw_breakpoint: Introduce "struct bp_cpuinfo" hw_breakpoint: Simplify *register_wide_hw_breakpoint() hw_breakpoint: Introduce cpumask_of_bp() hw_breakpoint: Simplify the "weight" usage in toggle_bp_slot() paths hw_breakpoint: Simplify list/idx mess in toggle_bp_slot() paths perf/x86/intel: Add mem-loads/stores support for Haswell perf/x86/intel: Support Haswell/v4 LBR format perf/x86/intel: Move NMI clearing to end of PMI handler perf/x86/intel: Add Haswell PEBS support perf/x86/intel: Add simple Haswell PMU support perf/x86/intel: Add Haswell PEBS record support perf/x86/intel: Fix sparse warning perf/x86/amd: AMD IOMMU Performance Counter PERF uncore PMU implementation perf/x86/amd: Add IOMMU Performance Counter resource management ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/events/core.c278
-rw-r--r--kernel/events/hw_breakpoint.c191
-rw-r--r--kernel/sysctl.c12
3 files changed, 350 insertions, 131 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index b391907d5352..1db3af933704 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -165,10 +165,28 @@ int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free'
/*
* max perf event sample rate
*/
-#define DEFAULT_MAX_SAMPLE_RATE 100000
-int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE;
-static int max_samples_per_tick __read_mostly =
- DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ);
+#define DEFAULT_MAX_SAMPLE_RATE 100000
+#define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE)
+#define DEFAULT_CPU_TIME_MAX_PERCENT 25
+
+int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE;
+
+static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ);
+static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS;
+
+static atomic_t perf_sample_allowed_ns __read_mostly =
+ ATOMIC_INIT( DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100);
+
+void update_perf_cpu_limits(void)
+{
+ u64 tmp = perf_sample_period_ns;
+
+ tmp *= sysctl_perf_cpu_time_max_percent;
+ tmp = do_div(tmp, 100);
+ atomic_set(&perf_sample_allowed_ns, tmp);
+}
+
+static int perf_rotate_context(struct perf_cpu_context *cpuctx);
int perf_proc_update_handler(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
@@ -180,10 +198,78 @@ int perf_proc_update_handler(struct ctl_table *table, int write,
return ret;
max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ);
+ perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate;
+ update_perf_cpu_limits();
return 0;
}
+int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT;
+
+int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos)
+{
+ int ret = proc_dointvec(table, write, buffer, lenp, ppos);
+
+ if (ret || !write)
+ return ret;
+
+ update_perf_cpu_limits();
+
+ return 0;
+}
+
+/*
+ * perf samples are done in some very critical code paths (NMIs).
+ * If they take too much CPU time, the system can lock up and not
+ * get any real work done. This will drop the sample rate when
+ * we detect that events are taking too long.
+ */
+#define NR_ACCUMULATED_SAMPLES 128
+DEFINE_PER_CPU(u64, running_sample_length);
+
+void perf_sample_event_took(u64 sample_len_ns)
+{
+ u64 avg_local_sample_len;
+ u64 local_samples_len = __get_cpu_var(running_sample_length);
+
+ if (atomic_read(&perf_sample_allowed_ns) == 0)
+ return;
+
+ /* decay the counter by 1 average sample */
+ local_samples_len = __get_cpu_var(running_sample_length);
+ local_samples_len -= local_samples_len/NR_ACCUMULATED_SAMPLES;
+ local_samples_len += sample_len_ns;
+ __get_cpu_var(running_sample_length) = local_samples_len;
+
+ /*
+ * note: this will be biased artifically low until we have
+ * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us
+ * from having to maintain a count.
+ */
+ avg_local_sample_len = local_samples_len/NR_ACCUMULATED_SAMPLES;
+
+ if (avg_local_sample_len <= atomic_read(&perf_sample_allowed_ns))
+ return;
+
+ if (max_samples_per_tick <= 1)
+ return;
+
+ max_samples_per_tick = DIV_ROUND_UP(max_samples_per_tick, 2);
+ sysctl_perf_event_sample_rate = max_samples_per_tick * HZ;
+ perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate;
+
+ printk_ratelimited(KERN_WARNING
+ "perf samples too long (%lld > %d), lowering "
+ "kernel.perf_event_max_sample_rate to %d\n",
+ avg_local_sample_len,
+ atomic_read(&perf_sample_allowed_ns),
+ sysctl_perf_event_sample_rate);
+
+ update_perf_cpu_limits();
+}
+
static atomic64_t perf_event_id;
static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx,
@@ -655,6 +741,106 @@ perf_cgroup_mark_enabled(struct perf_event *event,
}
#endif
+/*
+ * set default to be dependent on timer tick just
+ * like original code
+ */
+#define PERF_CPU_HRTIMER (1000 / HZ)
+/*
+ * function must be called with interrupts disbled
+ */
+static enum hrtimer_restart perf_cpu_hrtimer_handler(struct hrtimer *hr)
+{
+ struct perf_cpu_context *cpuctx;
+ enum hrtimer_restart ret = HRTIMER_NORESTART;
+ int rotations = 0;
+
+ WARN_ON(!irqs_disabled());
+
+ cpuctx = container_of(hr, struct perf_cpu_context, hrtimer);
+
+ rotations = perf_rotate_context(cpuctx);
+
+ /*
+ * arm timer if needed
+ */
+ if (rotations) {
+ hrtimer_forward_now(hr, cpuctx->hrtimer_interval);
+ ret = HRTIMER_RESTART;
+ }
+
+ return ret;
+}
+
+/* CPU is going down */
+void perf_cpu_hrtimer_cancel(int cpu)
+{
+ struct perf_cpu_context *cpuctx;
+ struct pmu *pmu;
+ unsigned long flags;
+
+ if (WARN_ON(cpu != smp_processor_id()))
+ return;
+
+ local_irq_save(flags);
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(pmu, &pmus, entry) {
+ cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
+
+ if (pmu->task_ctx_nr == perf_sw_context)
+ continue;
+
+ hrtimer_cancel(&cpuctx->hrtimer);
+ }
+
+ rcu_read_unlock();
+
+ local_irq_restore(flags);
+}
+
+static void __perf_cpu_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu)
+{
+ struct hrtimer *hr = &cpuctx->hrtimer;
+ struct pmu *pmu = cpuctx->ctx.pmu;
+ int timer;
+
+ /* no multiplexing needed for SW PMU */
+ if (pmu->task_ctx_nr == perf_sw_context)
+ return;
+
+ /*
+ * check default is sane, if not set then force to
+ * default interval (1/tick)
+ */
+ timer = pmu->hrtimer_interval_ms;
+ if (timer < 1)
+ timer = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER;
+
+ cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer);
+
+ hrtimer_init(hr, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
+ hr->function = perf_cpu_hrtimer_handler;
+}
+
+static void perf_cpu_hrtimer_restart(struct perf_cpu_context *cpuctx)
+{
+ struct hrtimer *hr = &cpuctx->hrtimer;
+ struct pmu *pmu = cpuctx->ctx.pmu;
+
+ /* not for SW PMU */
+ if (pmu->task_ctx_nr == perf_sw_context)
+ return;
+
+ if (hrtimer_active(hr))
+ return;
+
+ if (!hrtimer_callback_running(hr))
+ __hrtimer_start_range_ns(hr, cpuctx->hrtimer_interval,
+ 0, HRTIMER_MODE_REL_PINNED, 0);
+}
+
void perf_pmu_disable(struct pmu *pmu)
{
int *count = this_cpu_ptr(pmu->pmu_disable_count);
@@ -1503,6 +1689,7 @@ group_sched_in(struct perf_event *group_event,
if (event_sched_in(group_event, cpuctx, ctx)) {
pmu->cancel_txn(pmu);
+ perf_cpu_hrtimer_restart(cpuctx);
return -EAGAIN;
}
@@ -1549,6 +1736,8 @@ group_error:
pmu->cancel_txn(pmu);
+ perf_cpu_hrtimer_restart(cpuctx);
+
return -EAGAIN;
}
@@ -1804,8 +1993,10 @@ static int __perf_event_enable(void *info)
* If this event can't go on and it's part of a
* group, then the whole group has to come off.
*/
- if (leader != event)
+ if (leader != event) {
group_sched_out(leader, cpuctx, ctx);
+ perf_cpu_hrtimer_restart(cpuctx);
+ }
if (leader->attr.pinned) {
update_group_times(leader);
leader->state = PERF_EVENT_STATE_ERROR;
@@ -2552,7 +2743,7 @@ static void rotate_ctx(struct perf_event_context *ctx)
* because they're strictly cpu affine and rotate_start is called with IRQs
* disabled, while rotate_context is called from IRQ context.
*/
-static void perf_rotate_context(struct perf_cpu_context *cpuctx)
+static int perf_rotate_context(struct perf_cpu_context *cpuctx)
{
struct perf_event_context *ctx = NULL;
int rotate = 0, remove = 1;
@@ -2591,6 +2782,8 @@ static void perf_rotate_context(struct perf_cpu_context *cpuctx)
done:
if (remove)
list_del_init(&cpuctx->rotation_list);
+
+ return rotate;
}
#ifdef CONFIG_NO_HZ_FULL
@@ -2622,10 +2815,6 @@ void perf_event_task_tick(void)
ctx = cpuctx->task_ctx;
if (ctx)
perf_adjust_freq_unthr_context(ctx, throttled);
-
- if (cpuctx->jiffies_interval == 1 ||
- !(jiffies % cpuctx->jiffies_interval))
- perf_rotate_context(cpuctx);
}
}
@@ -5036,7 +5225,7 @@ static DEFINE_PER_CPU(struct swevent_htable, swevent_htable);
* sign as trigger.
*/
-static u64 perf_swevent_set_period(struct perf_event *event)
+u64 perf_swevent_set_period(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
u64 period = hwc->last_period;
@@ -5979,9 +6168,56 @@ type_show(struct device *dev, struct device_attribute *attr, char *page)
return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type);
}
+static ssize_t
+perf_event_mux_interval_ms_show(struct device *dev,
+ struct device_attribute *attr,
+ char *page)
+{
+ struct pmu *pmu = dev_get_drvdata(dev);
+
+ return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms);
+}
+
+static ssize_t
+perf_event_mux_interval_ms_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct pmu *pmu = dev_get_drvdata(dev);
+ int timer, cpu, ret;
+
+ ret = kstrtoint(buf, 0, &timer);
+ if (ret)
+ return ret;
+
+ if (timer < 1)
+ return -EINVAL;
+
+ /* same value, noting to do */
+ if (timer == pmu->hrtimer_interval_ms)
+ return count;
+
+ pmu->hrtimer_interval_ms = timer;
+
+ /* update all cpuctx for this PMU */
+ for_each_possible_cpu(cpu) {
+ struct perf_cpu_context *cpuctx;
+ cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu);
+ cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer);
+
+ if (hrtimer_active(&cpuctx->hrtimer))
+ hrtimer_forward_now(&cpuctx->hrtimer, cpuctx->hrtimer_interval);
+ }
+
+ return count;
+}
+
+#define __ATTR_RW(attr) __ATTR(attr, 0644, attr##_show, attr##_store)
+
static struct device_attribute pmu_dev_attrs[] = {
- __ATTR_RO(type),
- __ATTR_NULL,
+ __ATTR_RO(type),
+ __ATTR_RW(perf_event_mux_interval_ms),
+ __ATTR_NULL,
};
static int pmu_bus_running;
@@ -6027,7 +6263,7 @@ free_dev:
static struct lock_class_key cpuctx_mutex;
static struct lock_class_key cpuctx_lock;
-int perf_pmu_register(struct pmu *pmu, char *name, int type)
+int perf_pmu_register(struct pmu *pmu, const char *name, int type)
{
int cpu, ret;
@@ -6076,7 +6312,9 @@ skip_type:
lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock);
cpuctx->ctx.type = cpu_context;
cpuctx->ctx.pmu = pmu;
- cpuctx->jiffies_interval = 1;
+
+ __perf_cpu_hrtimer_init(cpuctx, cpu);
+
INIT_LIST_HEAD(&cpuctx->rotation_list);
cpuctx->unique_pmu = pmu;
}
@@ -6402,11 +6640,6 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr,
if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL))
return -EINVAL;
- /* kernel level capture: check permissions */
- if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM)
- && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
- return -EACCES;
-
/* propagate priv level, when not set for branch */
if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) {
@@ -6424,6 +6657,10 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr,
*/
attr->branch_sample_type = mask;
}
+ /* privileged levels capture (kernel, hv): check permissions */
+ if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM)
+ && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
+ return -EACCES;
}
if (attr->sample_type & PERF_SAMPLE_REGS_USER) {
@@ -7476,7 +7713,6 @@ perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
case CPU_DOWN_PREPARE:
perf_event_exit_cpu(cpu);
break;
-
default:
break;
}
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index 20185ea64aa6..1559fb0b9296 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -46,23 +46,26 @@
#include <linux/smp.h>
#include <linux/hw_breakpoint.h>
-
-
/*
* Constraints data
*/
+struct bp_cpuinfo {
+ /* Number of pinned cpu breakpoints in a cpu */
+ unsigned int cpu_pinned;
+ /* tsk_pinned[n] is the number of tasks having n+1 breakpoints */
+ unsigned int *tsk_pinned;
+ /* Number of non-pinned cpu/task breakpoints in a cpu */
+ unsigned int flexible; /* XXX: placeholder, see fetch_this_slot() */
+};
-/* Number of pinned cpu breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int, nr_cpu_bp_pinned[TYPE_MAX]);
-
-/* Number of pinned task breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int *, nr_task_bp_pinned[TYPE_MAX]);
-
-/* Number of non-pinned cpu/task breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int, nr_bp_flexible[TYPE_MAX]);
-
+static DEFINE_PER_CPU(struct bp_cpuinfo, bp_cpuinfo[TYPE_MAX]);
static int nr_slots[TYPE_MAX];
+static struct bp_cpuinfo *get_bp_info(int cpu, enum bp_type_idx type)
+{
+ return per_cpu_ptr(bp_cpuinfo + type, cpu);
+}
+
/* Keep track of the breakpoints attached to tasks */
static LIST_HEAD(bp_task_head);
@@ -96,8 +99,8 @@ static inline enum bp_type_idx find_slot_idx(struct perf_event *bp)
*/
static unsigned int max_task_bp_pinned(int cpu, enum bp_type_idx type)
{
+ unsigned int *tsk_pinned = get_bp_info(cpu, type)->tsk_pinned;
int i;
- unsigned int *tsk_pinned = per_cpu(nr_task_bp_pinned[type], cpu);
for (i = nr_slots[type] - 1; i >= 0; i--) {
if (tsk_pinned[i] > 0)
@@ -127,6 +130,13 @@ static int task_bp_pinned(int cpu, struct perf_event *bp, enum bp_type_idx type)
return count;
}
+static const struct cpumask *cpumask_of_bp(struct perf_event *bp)
+{
+ if (bp->cpu >= 0)
+ return cpumask_of(bp->cpu);
+ return cpu_possible_mask;
+}
+
/*
* Report the number of pinned/un-pinned breakpoints we have in
* a given cpu (cpu > -1) or in all of them (cpu = -1).
@@ -135,25 +145,15 @@ static void
fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp,
enum bp_type_idx type)
{
- int cpu = bp->cpu;
- struct task_struct *tsk = bp->hw.bp_target;
-
- if (cpu >= 0) {
- slots->pinned = per_cpu(nr_cpu_bp_pinned[type], cpu);
- if (!tsk)
- slots->pinned += max_task_bp_pinned(cpu, type);
- else
- slots->pinned += task_bp_pinned(cpu, bp, type);
- slots->flexible = per_cpu(nr_bp_flexible[type], cpu);
-
- return;
- }
+ const struct cpumask *cpumask = cpumask_of_bp(bp);
+ int cpu;
- for_each_possible_cpu(cpu) {
- unsigned int nr;
+ for_each_cpu(cpu, cpumask) {
+ struct bp_cpuinfo *info = get_bp_info(cpu, type);
+ int nr;
- nr = per_cpu(nr_cpu_bp_pinned[type], cpu);
- if (!tsk)
+ nr = info->cpu_pinned;
+ if (!bp->hw.bp_target)
nr += max_task_bp_pinned(cpu, type);
else
nr += task_bp_pinned(cpu, bp, type);
@@ -161,8 +161,7 @@ fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp,
if (nr > slots->pinned)
slots->pinned = nr;
- nr = per_cpu(nr_bp_flexible[type], cpu);
-
+ nr = info->flexible;
if (nr > slots->flexible)
slots->flexible = nr;
}
@@ -182,29 +181,19 @@ fetch_this_slot(struct bp_busy_slots *slots, int weight)
/*
* Add a pinned breakpoint for the given task in our constraint table
*/
-static void toggle_bp_task_slot(struct perf_event *bp, int cpu, bool enable,
+static void toggle_bp_task_slot(struct perf_event *bp, int cpu,
enum bp_type_idx type, int weight)
{
- unsigned int *tsk_pinned;
- int old_count = 0;
- int old_idx = 0;
- int idx = 0;
-
- old_count = task_bp_pinned(cpu, bp, type);
- old_idx = old_count - 1;
- idx = old_idx + weight;
-
- /* tsk_pinned[n] is the number of tasks having n breakpoints */
- tsk_pinned = per_cpu(nr_task_bp_pinned[type], cpu);
- if (enable) {
- tsk_pinned[idx]++;
- if (old_count > 0)
- tsk_pinned[old_idx]--;
- } else {
- tsk_pinned[idx]--;
- if (old_count > 0)
- tsk_pinned[old_idx]++;
- }
+ unsigned int *tsk_pinned = get_bp_info(cpu, type)->tsk_pinned;
+ int old_idx, new_idx;
+
+ old_idx = task_bp_pinned(cpu, bp, type) - 1;
+ new_idx = old_idx + weight;
+
+ if (old_idx >= 0)
+ tsk_pinned[old_idx]--;
+ if (new_idx >= 0)
+ tsk_pinned[new_idx]++;
}
/*
@@ -214,33 +203,26 @@ static void
toggle_bp_slot(struct perf_event *bp, bool enable, enum bp_type_idx type,
int weight)
{
- int cpu = bp->cpu;
- struct task_struct *tsk = bp->hw.bp_target;
+ const struct cpumask *cpumask = cpumask_of_bp(bp);
+ int cpu;
- /* Pinned counter cpu profiling */
- if (!tsk) {
+ if (!enable)
+ weight = -weight;
- if (enable)
- per_cpu(nr_cpu_bp_pinned[type], bp->cpu) += weight;
- else
- per_cpu(nr_cpu_bp_pinned[type], bp->cpu) -= weight;
+ /* Pinned counter cpu profiling */
+ if (!bp->hw.bp_target) {
+ get_bp_info(bp->cpu, type)->cpu_pinned += weight;
return;
}
/* Pinned counter task profiling */
-
- if (!enable)
- list_del(&bp->hw.bp_list);
-
- if (cpu >= 0) {
- toggle_bp_task_slot(bp, cpu, enable, type, weight);
- } else {
- for_each_possible_cpu(cpu)
- toggle_bp_task_slot(bp, cpu, enable, type, weight);
- }
+ for_each_cpu(cpu, cpumask)
+ toggle_bp_task_slot(bp, cpu, type, weight);
if (enable)
list_add_tail(&bp->hw.bp_list, &bp_task_head);
+ else
+ list_del(&bp->hw.bp_list);
}
/*
@@ -261,8 +243,8 @@ __weak void arch_unregister_hw_breakpoint(struct perf_event *bp)
*
* - If attached to a single cpu, check:
*
- * (per_cpu(nr_bp_flexible, cpu) || (per_cpu(nr_cpu_bp_pinned, cpu)
- * + max(per_cpu(nr_task_bp_pinned, cpu)))) < HBP_NUM
+ * (per_cpu(info->flexible, cpu) || (per_cpu(info->cpu_pinned, cpu)
+ * + max(per_cpu(info->tsk_pinned, cpu)))) < HBP_NUM
*
* -> If there are already non-pinned counters in this cpu, it means
* there is already a free slot for them.
@@ -272,8 +254,8 @@ __weak void arch_unregister_hw_breakpoint(struct perf_event *bp)
*
* - If attached to every cpus, check:
*
- * (per_cpu(nr_bp_flexible, *) || (max(per_cpu(nr_cpu_bp_pinned, *))
- * + max(per_cpu(nr_task_bp_pinned, *)))) < HBP_NUM
+ * (per_cpu(info->flexible, *) || (max(per_cpu(info->cpu_pinned, *))
+ * + max(per_cpu(info->tsk_pinned, *)))) < HBP_NUM
*
* -> This is roughly the same, except we check the number of per cpu
* bp for every cpu and we keep the max one. Same for the per tasks
@@ -284,16 +266,16 @@ __weak void arch_unregister_hw_breakpoint(struct perf_event *bp)
*
* - If attached to a single cpu, check:
*
- * ((per_cpu(nr_bp_flexible, cpu) > 1) + per_cpu(nr_cpu_bp_pinned, cpu)
- * + max(per_cpu(nr_task_bp_pinned, cpu))) < HBP_NUM
+ * ((per_cpu(info->flexible, cpu) > 1) + per_cpu(info->cpu_pinned, cpu)
+ * + max(per_cpu(info->tsk_pinned, cpu))) < HBP_NUM
*
- * -> Same checks as before. But now the nr_bp_flexible, if any, must keep
+ * -> Same checks as before. But now the info->flexible, if any, must keep
* one register at least (or they will never be fed).
*
* - If attached to every cpus, check:
*
- * ((per_cpu(nr_bp_flexible, *) > 1) + max(per_cpu(nr_cpu_bp_pinned, *))
- * + max(per_cpu(nr_task_bp_pinned, *))) < HBP_NUM
+ * ((per_cpu(info->flexible, *) > 1) + max(per_cpu(info->cpu_pinned, *))
+ * + max(per_cpu(info->tsk_pinned, *))) < HBP_NUM
*/
static int __reserve_bp_slot(struct perf_event *bp)
{
@@ -518,8 +500,8 @@ register_wide_hw_breakpoint(struct perf_event_attr *attr,
perf_overflow_handler_t triggered,
void *context)
{
- struct perf_event * __percpu *cpu_events, **pevent, *bp;
- long err;
+ struct perf_event * __percpu *cpu_events, *bp;
+ long err = 0;
int cpu;
cpu_events = alloc_percpu(typeof(*cpu_events));
@@ -528,31 +510,21 @@ register_wide_hw_breakpoint(struct perf_event_attr *attr,
get_online_cpus();
for_each_online_cpu(cpu) {
- pevent = per_cpu_ptr(cpu_events, cpu);
bp = perf_event_create_kernel_counter(attr, cpu, NULL,
triggered, context);
-
- *pevent = bp;
-
if (IS_ERR(bp)) {
err = PTR_ERR(bp);
- goto fail;
+ break;
}
- }
- put_online_cpus();
- return cpu_events;
-
-fail:
- for_each_online_cpu(cpu) {
- pevent = per_cpu_ptr(cpu_events, cpu);
- if (IS_ERR(*pevent))
- break;
- unregister_hw_breakpoint(*pevent);
+ per_cpu(*cpu_events, cpu) = bp;
}
put_online_cpus();
- free_percpu(cpu_events);
+ if (likely(!err))
+ return cpu_events;
+
+ unregister_wide_hw_breakpoint(cpu_events);
return (void __percpu __force *)ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(register_wide_hw_breakpoint);
@@ -564,12 +536,10 @@ EXPORT_SYMBOL_GPL(register_wide_hw_breakpoint);
void unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events)
{
int cpu;
- struct perf_event **pevent;
- for_each_possible_cpu(cpu) {
- pevent = per_cpu_ptr(cpu_events, cpu);
- unregister_hw_breakpoint(*pevent);
- }
+ for_each_possible_cpu(cpu)
+ unregister_hw_breakpoint(per_cpu(*cpu_events, cpu));
+
free_percpu(cpu_events);
}
EXPORT_SYMBOL_GPL(unregister_wide_hw_breakpoint);
@@ -612,6 +582,11 @@ static int hw_breakpoint_add(struct perf_event *bp, int flags)
if (!(flags & PERF_EF_START))
bp->hw.state = PERF_HES_STOPPED;
+ if (is_sampling_event(bp)) {
+ bp->hw.last_period = bp->hw.sample_period;
+ perf_swevent_set_period(bp);
+ }
+
return arch_install_hw_breakpoint(bp);
}
@@ -650,7 +625,6 @@ static struct pmu perf_breakpoint = {
int __init init_hw_breakpoint(void)
{
- unsigned int **task_bp_pinned;
int cpu, err_cpu;
int i;
@@ -659,10 +633,11 @@ int __init init_hw_breakpoint(void)
for_each_possible_cpu(cpu) {
for (i = 0; i < TYPE_MAX; i++) {
- task_bp_pinned = &per_cpu(nr_task_bp_pinned[i], cpu);
- *task_bp_pinned = kzalloc(sizeof(int) * nr_slots[i],
- GFP_KERNEL);
- if (!*task_bp_pinned)
+ struct bp_cpuinfo *info = get_bp_info(cpu, i);
+
+ info->tsk_pinned = kcalloc(nr_slots[i], sizeof(int),
+ GFP_KERNEL);
+ if (!info->tsk_pinned)
goto err_alloc;
}
}
@@ -676,7 +651,7 @@ int __init init_hw_breakpoint(void)
err_alloc:
for_each_possible_cpu(err_cpu) {
for (i = 0; i < TYPE_MAX; i++)
- kfree(per_cpu(nr_task_bp_pinned[i], err_cpu));
+ kfree(get_bp_info(err_cpu, i)->tsk_pinned);
if (err_cpu == cpu)
break;
}
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 9edcf456e0fc..4ce13c3cedb9 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -120,7 +120,6 @@ extern int blk_iopoll_enabled;
/* Constants used for minimum and maximum */
#ifdef CONFIG_LOCKUP_DETECTOR
static int sixty = 60;
-static int neg_one = -1;
#endif
static int zero;
@@ -814,7 +813,7 @@ static struct ctl_table kern_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dowatchdog,
- .extra1 = &neg_one,
+ .extra1 = &zero,
.extra2 = &sixty,
},
{
@@ -1044,6 +1043,15 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = perf_proc_update_handler,
},
+ {
+ .procname = "perf_cpu_time_max_percent",
+ .data = &sysctl_perf_cpu_time_max_percent,
+ .maxlen = sizeof(sysctl_perf_cpu_time_max_percent),
+ .mode = 0644,
+ .proc_handler = perf_cpu_time_max_percent_handler,
+ .extra1 = &zero,
+ .extra2 = &one_hundred,
+ },
#endif
#ifdef CONFIG_KMEMCHECK
{