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authorStephane Eranian <eranian@google.com>2010-10-20 15:25:01 +0200
committerIngo Molnar <mingo@elte.hu>2010-10-22 14:18:27 +0200
commit9ffcfa6f1f63eeac15555b745c292eb9f59130f6 (patch)
tree803cc11f312da98713fdfc366b7ec79351dffa55 /kernel/perf_event.c
parent96681fc3c9e7d1f89ab64e5eec40b6467c97680f (diff)
perf_events: Revert: Fix transaction recovery in group_sched_in()
This patch reverts commit 8e5fc1a (perf_events: Fix transaction recovery in group_sched_in()) because it had one flaw in case the group could never be scheduled. It would cause time_enabled to get negative. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <4cbeeeb7.0aefd80a.6e40.0e2f@mx.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/perf_event.c')
-rw-r--r--kernel/perf_event.c76
1 files changed, 13 insertions, 63 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index f309e8014c7..39afdb07d75 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -417,8 +417,8 @@ event_filter_match(struct perf_event *event)
return event->cpu == -1 || event->cpu == smp_processor_id();
}
-static int
-__event_sched_out(struct perf_event *event,
+static void
+event_sched_out(struct perf_event *event,
struct perf_cpu_context *cpuctx,
struct perf_event_context *ctx)
{
@@ -437,13 +437,14 @@ __event_sched_out(struct perf_event *event,
}
if (event->state != PERF_EVENT_STATE_ACTIVE)
- return 0;
+ return;
event->state = PERF_EVENT_STATE_INACTIVE;
if (event->pending_disable) {
event->pending_disable = 0;
event->state = PERF_EVENT_STATE_OFF;
}
+ event->tstamp_stopped = ctx->time;
event->pmu->del(event, 0);
event->oncpu = -1;
@@ -452,19 +453,6 @@ __event_sched_out(struct perf_event *event,
ctx->nr_active--;
if (event->attr.exclusive || !cpuctx->active_oncpu)
cpuctx->exclusive = 0;
- return 1;
-}
-
-static void
-event_sched_out(struct perf_event *event,
- struct perf_cpu_context *cpuctx,
- struct perf_event_context *ctx)
-{
- int ret;
-
- ret = __event_sched_out(event, cpuctx, ctx);
- if (ret)
- event->tstamp_stopped = ctx->time;
}
static void
@@ -664,7 +652,7 @@ retry:
}
static int
-__event_sched_in(struct perf_event *event,
+event_sched_in(struct perf_event *event,
struct perf_cpu_context *cpuctx,
struct perf_event_context *ctx)
{
@@ -684,6 +672,8 @@ __event_sched_in(struct perf_event *event,
return -EAGAIN;
}
+ event->tstamp_running += ctx->time - event->tstamp_stopped;
+
if (!is_software_event(event))
cpuctx->active_oncpu++;
ctx->nr_active++;
@@ -694,35 +684,6 @@ __event_sched_in(struct perf_event *event,
return 0;
}
-static inline int
-event_sched_in(struct perf_event *event,
- struct perf_cpu_context *cpuctx,
- struct perf_event_context *ctx)
-{
- int ret = __event_sched_in(event, cpuctx, ctx);
- if (ret)
- return ret;
- event->tstamp_running += ctx->time - event->tstamp_stopped;
- return 0;
-}
-
-static void
-group_commit_event_sched_in(struct perf_event *group_event,
- struct perf_cpu_context *cpuctx,
- struct perf_event_context *ctx)
-{
- struct perf_event *event;
- u64 now = ctx->time;
-
- group_event->tstamp_running += now - group_event->tstamp_stopped;
- /*
- * Schedule in siblings as one group (if any):
- */
- list_for_each_entry(event, &group_event->sibling_list, group_entry) {
- event->tstamp_running += now - event->tstamp_stopped;
- }
-}
-
static int
group_sched_in(struct perf_event *group_event,
struct perf_cpu_context *cpuctx,
@@ -736,13 +697,7 @@ group_sched_in(struct perf_event *group_event,
pmu->start_txn(pmu);
- /*
- * use __event_sched_in() to delay updating tstamp_running
- * until the transaction is committed. In case of failure
- * we will keep an unmodified tstamp_running which is a
- * requirement to get correct timing information
- */
- if (__event_sched_in(group_event, cpuctx, ctx)) {
+ if (event_sched_in(group_event, cpuctx, ctx)) {
pmu->cancel_txn(pmu);
return -EAGAIN;
}
@@ -751,31 +706,26 @@ group_sched_in(struct perf_event *group_event,
* Schedule in siblings as one group (if any):
*/
list_for_each_entry(event, &group_event->sibling_list, group_entry) {
- if (__event_sched_in(event, cpuctx, ctx)) {
+ if (event_sched_in(event, cpuctx, ctx)) {
partial_group = event;
goto group_error;
}
}
- if (!pmu->commit_txn(pmu)) {
- /* commit tstamp_running */
- group_commit_event_sched_in(group_event, cpuctx, ctx);
+ if (!pmu->commit_txn(pmu))
return 0;
- }
+
group_error:
/*
* Groups can be scheduled in as one unit only, so undo any
* partial group before returning:
- *
- * use __event_sched_out() to avoid updating tstamp_stopped
- * because the event never actually ran
*/
list_for_each_entry(event, &group_event->sibling_list, group_entry) {
if (event == partial_group)
break;
- __event_sched_out(event, cpuctx, ctx);
+ event_sched_out(event, cpuctx, ctx);
}
- __event_sched_out(group_event, cpuctx, ctx);
+ event_sched_out(group_event, cpuctx, ctx);
pmu->cancel_txn(pmu);