Merge commit 'v2.6.32-rc6' into perf/core
[linux-3.10.git] / kernel / perf_event.c
index 9ecaa45..a69d4ed 100644 (file)
@@ -3976,8 +3976,9 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
                regs = task_pt_regs(current);
 
        if (regs) {
-               if (perf_event_overflow(event, 0, &data, regs))
-                       ret = HRTIMER_NORESTART;
+               if (!(event->attr.exclude_idle && current->pid == 0))
+                       if (perf_event_overflow(event, 0, &data, regs))
+                               ret = HRTIMER_NORESTART;
        }
 
        period = max_t(u64, 10000, event->hw.sample_period);
@@ -3986,6 +3987,42 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
        return ret;
 }
 
+static void perf_swevent_start_hrtimer(struct perf_event *event)
+{
+       struct hw_perf_event *hwc = &event->hw;
+
+       hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+       hwc->hrtimer.function = perf_swevent_hrtimer;
+       if (hwc->sample_period) {
+               u64 period;
+
+               if (hwc->remaining) {
+                       if (hwc->remaining < 0)
+                               period = 10000;
+                       else
+                               period = hwc->remaining;
+                       hwc->remaining = 0;
+               } else {
+                       period = max_t(u64, 10000, hwc->sample_period);
+               }
+               __hrtimer_start_range_ns(&hwc->hrtimer,
+                               ns_to_ktime(period), 0,
+                               HRTIMER_MODE_REL, 0);
+       }
+}
+
+static void perf_swevent_cancel_hrtimer(struct perf_event *event)
+{
+       struct hw_perf_event *hwc = &event->hw;
+
+       if (hwc->sample_period) {
+               ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer);
+               hwc->remaining = ktime_to_ns(remaining);
+
+               hrtimer_cancel(&hwc->hrtimer);
+       }
+}
+
 /*
  * Software event: cpu wall time clock
  */
@@ -4008,22 +4045,14 @@ static int cpu_clock_perf_event_enable(struct perf_event *event)
        int cpu = raw_smp_processor_id();
 
        atomic64_set(&hwc->prev_count, cpu_clock(cpu));
-       hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-       hwc->hrtimer.function = perf_swevent_hrtimer;
-       if (hwc->sample_period) {
-               u64 period = max_t(u64, 10000, hwc->sample_period);
-               __hrtimer_start_range_ns(&hwc->hrtimer,
-                               ns_to_ktime(period), 0,
-                               HRTIMER_MODE_REL, 0);
-       }
+       perf_swevent_start_hrtimer(event);
 
        return 0;
 }
 
 static void cpu_clock_perf_event_disable(struct perf_event *event)
 {
-       if (event->hw.sample_period)
-               hrtimer_cancel(&event->hw.hrtimer);
+       perf_swevent_cancel_hrtimer(event);
        cpu_clock_perf_event_update(event);
 }
 
@@ -4060,22 +4089,15 @@ static int task_clock_perf_event_enable(struct perf_event *event)
        now = event->ctx->time;
 
        atomic64_set(&hwc->prev_count, now);
-       hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-       hwc->hrtimer.function = perf_swevent_hrtimer;
-       if (hwc->sample_period) {
-               u64 period = max_t(u64, 10000, hwc->sample_period);
-               __hrtimer_start_range_ns(&hwc->hrtimer,
-                               ns_to_ktime(period), 0,
-                               HRTIMER_MODE_REL, 0);
-       }
+
+       perf_swevent_start_hrtimer(event);
 
        return 0;
 }
 
 static void task_clock_perf_event_disable(struct perf_event *event)
 {
-       if (event->hw.sample_period)
-               hrtimer_cancel(&event->hw.hrtimer);
+       perf_swevent_cancel_hrtimer(event);
        task_clock_perf_event_update(event, event->ctx->time);
 
 }