[tip:perfcounters/core] perf_counter: round-robin per-CPU counters too

From: tip-bot for Ingo Molnar
Date: Mon May 04 2009 - 13:34:37 EST


Commit-ID: b82914ce33146186d554b0f5c41e4e13693614ce
Gitweb: http://git.kernel.org/tip/b82914ce33146186d554b0f5c41e4e13693614ce
Author: Ingo Molnar <mingo@xxxxxxx>
AuthorDate: Mon, 4 May 2009 18:54:32 +0200
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Mon, 4 May 2009 19:29:57 +0200

perf_counter: round-robin per-CPU counters too

This used to be unstable when we had the rq->lock dependencies,
but now that they are that of the past we can turn on percpu
counter RR too.

[ Impact: handle counter over-commit for per-CPU counters too ]

LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>


---
kernel/perf_counter.c | 10 +++-------
1 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index 8660ae5..b9679c3 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -1069,18 +1069,14 @@ void perf_counter_task_tick(struct task_struct *curr, int cpu)
{
struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
struct perf_counter_context *ctx = &curr->perf_counter_ctx;
- const int rotate_percpu = 0;

- if (rotate_percpu)
- perf_counter_cpu_sched_out(cpuctx);
+ perf_counter_cpu_sched_out(cpuctx);
perf_counter_task_sched_out(curr, cpu);

- if (rotate_percpu)
- rotate_ctx(&cpuctx->ctx);
+ rotate_ctx(&cpuctx->ctx);
rotate_ctx(ctx);

- if (rotate_percpu)
- perf_counter_cpu_sched_in(cpuctx, cpu);
+ perf_counter_cpu_sched_in(cpuctx, cpu);
perf_counter_task_sched_in(curr, cpu);
}

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/