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-rw-r--r--kernel/perf_event.c105
1 files changed, 55 insertions, 50 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 4393b9e7374..3d1552d3c12 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -15,6 +15,7 @@
#include <linux/smp.h>
#include <linux/file.h>
#include <linux/poll.h>
+#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/dcache.h>
#include <linux/percpu.h>
@@ -81,10 +82,6 @@ extern __weak const struct pmu *hw_perf_event_init(struct perf_event *event)
void __weak hw_perf_disable(void) { barrier(); }
void __weak hw_perf_enable(void) { barrier(); }
-void __weak hw_perf_event_setup(int cpu) { barrier(); }
-void __weak hw_perf_event_setup_online(int cpu) { barrier(); }
-void __weak hw_perf_event_setup_offline(int cpu) { barrier(); }
-
int __weak
hw_perf_group_sched_in(struct perf_event *group_leader,
struct perf_cpu_context *cpuctx,
@@ -97,25 +94,15 @@ void __weak perf_event_print_debug(void) { }
static DEFINE_PER_CPU(int, perf_disable_count);
-void __perf_disable(void)
-{
- __get_cpu_var(perf_disable_count)++;
-}
-
-bool __perf_enable(void)
-{
- return !--__get_cpu_var(perf_disable_count);
-}
-
void perf_disable(void)
{
- __perf_disable();
- hw_perf_disable();
+ if (!__get_cpu_var(perf_disable_count)++)
+ hw_perf_disable();
}
void perf_enable(void)
{
- if (__perf_enable())
+ if (!--__get_cpu_var(perf_disable_count))
hw_perf_enable();
}
@@ -1178,11 +1165,9 @@ void perf_event_task_sched_out(struct task_struct *task,
struct perf_event_context *ctx = task->perf_event_ctxp;
struct perf_event_context *next_ctx;
struct perf_event_context *parent;
- struct pt_regs *regs;
int do_switch = 1;
- regs = task_pt_regs(task);
- perf_sw_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 1, regs, 0);
+ perf_sw_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 1, NULL, 0);
if (likely(!ctx || !cpuctx->task_ctx))
return;
@@ -1538,12 +1523,15 @@ static void perf_ctx_adjust_freq(struct perf_event_context *ctx)
*/
if (interrupts == MAX_INTERRUPTS) {
perf_log_throttle(event, 1);
+ perf_disable();
event->pmu->unthrottle(event);
+ perf_enable();
}
if (!event->attr.freq || !event->attr.sample_freq)
continue;
+ perf_disable();
event->pmu->read(event);
now = atomic64_read(&event->count);
delta = now - hwc->freq_count_stamp;
@@ -1551,6 +1539,7 @@ static void perf_ctx_adjust_freq(struct perf_event_context *ctx)
if (delta > 0)
perf_adjust_period(event, TICK_NSEC, delta);
+ perf_enable();
}
raw_spin_unlock(&ctx->lock);
}
@@ -1560,9 +1549,6 @@ static void perf_ctx_adjust_freq(struct perf_event_context *ctx)
*/
static void rotate_ctx(struct perf_event_context *ctx)
{
- if (!ctx->nr_events)
- return;
-
raw_spin_lock(&ctx->lock);
/* Rotate the first entry last of non-pinned groups */
@@ -1575,19 +1561,28 @@ void perf_event_task_tick(struct task_struct *curr)
{
struct perf_cpu_context *cpuctx;
struct perf_event_context *ctx;
+ int rotate = 0;
if (!atomic_read(&nr_events))
return;
cpuctx = &__get_cpu_var(perf_cpu_context);
- ctx = curr->perf_event_ctxp;
+ if (cpuctx->ctx.nr_events &&
+ cpuctx->ctx.nr_events != cpuctx->ctx.nr_active)
+ rotate = 1;
- perf_disable();
+ ctx = curr->perf_event_ctxp;
+ if (ctx && ctx->nr_events && ctx->nr_events != ctx->nr_active)
+ rotate = 1;
perf_ctx_adjust_freq(&cpuctx->ctx);
if (ctx)
perf_ctx_adjust_freq(ctx);
+ if (!rotate)
+ return;
+
+ perf_disable();
cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
if (ctx)
task_ctx_sched_out(ctx, EVENT_FLEXIBLE);
@@ -1599,7 +1594,6 @@ void perf_event_task_tick(struct task_struct *curr)
cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE);
if (ctx)
task_ctx_sched_in(curr, EVENT_FLEXIBLE);
-
perf_enable();
}
@@ -2791,6 +2785,12 @@ __weak struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
return NULL;
}
+__weak
+void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int skip)
+{
+}
+
+
/*
* Output
*/
@@ -3376,15 +3376,23 @@ static void perf_event_task_output(struct perf_event *event,
struct perf_task_event *task_event)
{
struct perf_output_handle handle;
- int size;
struct task_struct *task = task_event->task;
- int ret;
+ unsigned long flags;
+ int size, ret;
+
+ /*
+ * If this CPU attempts to acquire an rq lock held by a CPU spinning
+ * in perf_output_lock() from interrupt context, it's game over.
+ */
+ local_irq_save(flags);
size = task_event->event_id.header.size;
ret = perf_output_begin(&handle, event, size, 0, 0);
- if (ret)
+ if (ret) {
+ local_irq_restore(flags);
return;
+ }
task_event->event_id.pid = perf_event_pid(event, task);
task_event->event_id.ppid = perf_event_pid(event, current);
@@ -3395,6 +3403,7 @@ static void perf_event_task_output(struct perf_event *event,
perf_output_put(&handle, task_event->event_id);
perf_output_end(&handle);
+ local_irq_restore(flags);
}
static int perf_event_task_match(struct perf_event *event)
@@ -4318,9 +4327,8 @@ static const struct pmu perf_ops_task_clock = {
#ifdef CONFIG_EVENT_TRACING
void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
- int entry_size)
+ int entry_size, struct pt_regs *regs)
{
- struct pt_regs *regs = get_irq_regs();
struct perf_sample_data data;
struct perf_raw_record raw = {
.size = entry_size,
@@ -4330,12 +4338,9 @@ void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
perf_sample_data_init(&data, addr);
data.raw = &raw;
- if (!regs)
- regs = task_pt_regs(current);
-
/* Trace events already protected against recursion */
do_perf_sw_event(PERF_TYPE_TRACEPOINT, event_id, count, 1,
- &data, regs);
+ &data, regs);
}
EXPORT_SYMBOL_GPL(perf_tp_event);
@@ -4351,7 +4356,7 @@ static int perf_tp_event_match(struct perf_event *event,
static void tp_perf_event_destroy(struct perf_event *event)
{
- ftrace_profile_disable(event->attr.config);
+ perf_trace_disable(event->attr.config);
}
static const struct pmu *tp_perf_event_init(struct perf_event *event)
@@ -4365,7 +4370,7 @@ static const struct pmu *tp_perf_event_init(struct perf_event *event)
!capable(CAP_SYS_ADMIN))
return ERR_PTR(-EPERM);
- if (ftrace_profile_enable(event->attr.config))
+ if (perf_trace_enable(event->attr.config))
return NULL;
event->destroy = tp_perf_event_destroy;
@@ -4892,7 +4897,7 @@ err_fput_free_put_context:
err_free_put_context:
if (err < 0)
- kfree(event);
+ free_event(event);
err_put_context:
if (err < 0)
@@ -5372,18 +5377,26 @@ int perf_event_init_task(struct task_struct *child)
return ret;
}
+static void __init perf_event_init_all_cpus(void)
+{
+ int cpu;
+ struct perf_cpu_context *cpuctx;
+
+ for_each_possible_cpu(cpu) {
+ cpuctx = &per_cpu(perf_cpu_context, cpu);
+ __perf_event_init_context(&cpuctx->ctx, NULL);
+ }
+}
+
static void __cpuinit perf_event_init_cpu(int cpu)
{
struct perf_cpu_context *cpuctx;
cpuctx = &per_cpu(perf_cpu_context, cpu);
- __perf_event_init_context(&cpuctx->ctx, NULL);
spin_lock(&perf_resource_lock);
cpuctx->max_pertask = perf_max_events - perf_reserved_percpu;
spin_unlock(&perf_resource_lock);
-
- hw_perf_event_setup(cpu);
}
#ifdef CONFIG_HOTPLUG_CPU
@@ -5423,20 +5436,11 @@ perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
perf_event_init_cpu(cpu);
break;
- case CPU_ONLINE:
- case CPU_ONLINE_FROZEN:
- hw_perf_event_setup_online(cpu);
- break;
-
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
perf_event_exit_cpu(cpu);
break;
- case CPU_DEAD:
- hw_perf_event_setup_offline(cpu);
- break;
-
default:
break;
}
@@ -5454,6 +5458,7 @@ static struct notifier_block __cpuinitdata perf_cpu_nb = {
void __init perf_event_init(void)
{
+ perf_event_init_all_cpus();
perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_UP_PREPARE,
(void *)(long)smp_processor_id());
perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_ONLINE,
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-29 07:25:04 +0000