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Diffstat (limited to 'arch/x86/kernel/cpu/perf_event.c')
-rw-r--r--arch/x86/kernel/cpu/perf_event.c106
1 files changed, 61 insertions, 45 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 79705ac45019..dd6fec710677 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -583,7 +583,7 @@ static void x86_pmu_disable_all(void)
}
}
-static void x86_pmu_pmu_disable(struct pmu *pmu)
+static void x86_pmu_disable(struct pmu *pmu)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
@@ -800,10 +800,10 @@ static inline int match_prev_assignment(struct hw_perf_event *hwc,
hwc->last_tag == cpuc->tags[i];
}
-static int x86_pmu_start(struct perf_event *event);
-static void x86_pmu_stop(struct perf_event *event);
+static void x86_pmu_start(struct perf_event *event, int flags);
+static void x86_pmu_stop(struct perf_event *event, int flags);
-static void x86_pmu_pmu_enable(struct pmu *pmu)
+static void x86_pmu_enable(struct pmu *pmu)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
struct perf_event *event;
@@ -839,7 +839,14 @@ static void x86_pmu_pmu_enable(struct pmu *pmu)
match_prev_assignment(hwc, cpuc, i))
continue;
- x86_pmu_stop(event);
+ /*
+ * Ensure we don't accidentally enable a stopped
+ * counter simply because we rescheduled.
+ */
+ if (hwc->state & PERF_HES_STOPPED)
+ hwc->state |= PERF_HES_ARCH;
+
+ x86_pmu_stop(event, PERF_EF_UPDATE);
}
for (i = 0; i < cpuc->n_events; i++) {
@@ -851,7 +858,10 @@ static void x86_pmu_pmu_enable(struct pmu *pmu)
else if (i < n_running)
continue;
- x86_pmu_start(event);
+ if (hwc->state & PERF_HES_ARCH)
+ continue;
+
+ x86_pmu_start(event, PERF_EF_RELOAD);
}
cpuc->n_added = 0;
perf_events_lapic_init();
@@ -952,15 +962,12 @@ static void x86_pmu_enable_event(struct perf_event *event)
}
/*
- * activate a single event
+ * Add a single event to the PMU.
*
* The event is added to the group of enabled events
* but only if it can be scehduled with existing events.
- *
- * Called with PMU disabled. If successful and return value 1,
- * then guaranteed to call perf_enable() and hw_perf_enable()
*/
-static int x86_pmu_enable(struct perf_event *event)
+static int x86_pmu_add(struct perf_event *event, int flags)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
struct hw_perf_event *hwc;
@@ -975,10 +982,14 @@ static int x86_pmu_enable(struct perf_event *event)
if (ret < 0)
goto out;
+ hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+ if (!(flags & PERF_EF_START))
+ hwc->state |= PERF_HES_ARCH;
+
/*
* If group events scheduling transaction was started,
* skip the schedulability test here, it will be peformed
- * at commit time(->commit_txn) as a whole
+ * at commit time (->commit_txn) as a whole
*/
if (cpuc->group_flag & PERF_EVENT_TXN)
goto done_collect;
@@ -1003,27 +1014,28 @@ out:
return ret;
}
-static int x86_pmu_start(struct perf_event *event)
+static void x86_pmu_start(struct perf_event *event, int flags)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
int idx = event->hw.idx;
- if (idx == -1)
- return -EAGAIN;
+ if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
+ return;
+
+ if (WARN_ON_ONCE(idx == -1))
+ return;
+
+ if (flags & PERF_EF_RELOAD) {
+ WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE));
+ x86_perf_event_set_period(event);
+ }
+
+ event->hw.state = 0;
- x86_perf_event_set_period(event);
cpuc->events[idx] = event;
__set_bit(idx, cpuc->active_mask);
x86_pmu.enable(event);
perf_event_update_userpage(event);
-
- return 0;
-}
-
-static void x86_pmu_unthrottle(struct perf_event *event)
-{
- int ret = x86_pmu_start(event);
- WARN_ON_ONCE(ret);
}
void perf_event_print_debug(void)
@@ -1080,27 +1092,29 @@ void perf_event_print_debug(void)
local_irq_restore(flags);
}
-static void x86_pmu_stop(struct perf_event *event)
+static void x86_pmu_stop(struct perf_event *event, int flags)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
struct hw_perf_event *hwc = &event->hw;
- int idx = hwc->idx;
-
- if (!__test_and_clear_bit(idx, cpuc->active_mask))
- return;
-
- x86_pmu.disable(event);
- /*
- * Drain the remaining delta count out of a event
- * that we are disabling:
- */
- x86_perf_event_update(event);
+ if (__test_and_clear_bit(hwc->idx, cpuc->active_mask)) {
+ x86_pmu.disable(event);
+ cpuc->events[hwc->idx] = NULL;
+ WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
+ hwc->state |= PERF_HES_STOPPED;
+ }
- cpuc->events[idx] = NULL;
+ if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) {
+ /*
+ * Drain the remaining delta count out of a event
+ * that we are disabling:
+ */
+ x86_perf_event_update(event);
+ hwc->state |= PERF_HES_UPTODATE;
+ }
}
-static void x86_pmu_disable(struct perf_event *event)
+static void x86_pmu_del(struct perf_event *event, int flags)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
int i;
@@ -1113,7 +1127,7 @@ static void x86_pmu_disable(struct perf_event *event)
if (cpuc->group_flag & PERF_EVENT_TXN)
return;
- x86_pmu_stop(event);
+ x86_pmu_stop(event, PERF_EF_UPDATE);
for (i = 0; i < cpuc->n_events; i++) {
if (event == cpuc->event_list[i]) {
@@ -1165,7 +1179,7 @@ static int x86_pmu_handle_irq(struct pt_regs *regs)
continue;
if (perf_event_overflow(event, 1, &data, regs))
- x86_pmu_stop(event);
+ x86_pmu_stop(event, 0);
}
if (handled)
@@ -1605,15 +1619,17 @@ int x86_pmu_event_init(struct perf_event *event)
}
static struct pmu pmu = {
- .pmu_enable = x86_pmu_pmu_enable,
- .pmu_disable = x86_pmu_pmu_disable,
+ .pmu_enable = x86_pmu_enable,
+ .pmu_disable = x86_pmu_disable,
+
.event_init = x86_pmu_event_init,
- .enable = x86_pmu_enable,
- .disable = x86_pmu_disable,
+
+ .add = x86_pmu_add,
+ .del = x86_pmu_del,
.start = x86_pmu_start,
.stop = x86_pmu_stop,
.read = x86_pmu_read,
- .unthrottle = x86_pmu_unthrottle,
+
.start_txn = x86_pmu_start_txn,
.cancel_txn = x86_pmu_cancel_txn,
.commit_txn = x86_pmu_commit_txn,
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