perf: Better order flexible and pinned scheduling
When a task gets scheduled in. We don't touch the cpu bound events
so the priority order becomes:
cpu pinned, cpu flexible, task pinned, task flexible.
So schedule out cpu flexibles when a new task context gets in
and correctly order the groups to schedule in:
task pinned, cpu flexible, task flexible.
Cpu pinned groups don't need to be touched at this time.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index a90ae69..edc46b9 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -1362,6 +1362,14 @@
raw_spin_unlock(&ctx->lock);
}
+static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx,
+ enum event_type_t event_type)
+{
+ struct perf_event_context *ctx = &cpuctx->ctx;
+
+ ctx_sched_in(ctx, cpuctx, event_type);
+}
+
static void task_ctx_sched_in(struct task_struct *task,
enum event_type_t event_type)
{
@@ -1388,15 +1396,27 @@
*/
void perf_event_task_sched_in(struct task_struct *task)
{
- task_ctx_sched_in(task, EVENT_ALL);
-}
+ struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+ struct perf_event_context *ctx = task->perf_event_ctxp;
-static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx,
- enum event_type_t event_type)
-{
- struct perf_event_context *ctx = &cpuctx->ctx;
+ if (likely(!ctx))
+ return;
- ctx_sched_in(ctx, cpuctx, event_type);
+ if (cpuctx->task_ctx == ctx)
+ return;
+
+ /*
+ * We want to keep the following priority order:
+ * cpu pinned (that don't need to move), task pinned,
+ * cpu flexible, task flexible.
+ */
+ cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
+
+ ctx_sched_in(ctx, cpuctx, EVENT_PINNED);
+ cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE);
+ ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE);
+
+ cpuctx->task_ctx = ctx;
}
#define MAX_INTERRUPTS (~0ULL)
