From e220d2dcb944c5c488b6855d15ec66d76900514f Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sat, 23 May 2009 18:28:55 +0200 Subject: [PATCH] perf_counter: Fix dynamic irq_period logging We call perf_adjust_freq() from perf_counter_task_tick() which is is called under the rq->lock causing lock recursion. However, it's no longer required to be called under the rq->lock, so remove it from under it. Also, fix up some related comments. Signed-off-by: Peter Zijlstra Cc: Paul Mackerras Cc: Corey Ashford Cc: Arnaldo Carvalho de Melo Cc: John Kacur LKML-Reference: <20090523163012.476197912@chello.nl> Signed-off-by: Ingo Molnar --- include/linux/perf_counter.h | 1 + kernel/perf_counter.c | 3 ++- kernel/sched.c | 3 ++- 3 files changed, 5 insertions(+), 2 deletions(-) diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h index 2eedae8498d3..23ddd29730f8 100644 --- a/include/linux/perf_counter.h +++ b/include/linux/perf_counter.h @@ -260,6 +260,7 @@ enum perf_event_type { /* * struct { * struct perf_event_header header; + * u64 time; * u64 irq_period; * }; */ diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index c10055416dea..2f410ea2cb39 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -2559,7 +2559,8 @@ void perf_counter_munmap(unsigned long addr, unsigned long len, } /* - * + * Log irq_period changes so that analyzing tools can re-normalize the + * event flow. */ static void perf_log_period(struct perf_counter *counter, u64 period) diff --git a/kernel/sched.c b/kernel/sched.c index 4c0d58bce6b2..ad079f07c9c8 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -4875,9 +4875,10 @@ void scheduler_tick(void) update_rq_clock(rq); update_cpu_load(rq); curr->sched_class->task_tick(rq, curr, 0); - perf_counter_task_tick(curr, cpu); spin_unlock(&rq->lock); + perf_counter_task_tick(curr, cpu); + #ifdef CONFIG_SMP rq->idle_at_tick = idle_cpu(cpu); trigger_load_balance(rq, cpu);