From 339f7c90b8a2f3aa2dd4267e79f797999e8a3c59 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 6 Apr 2009 11:45:06 +0200 Subject: [PATCH] perf_counter: PERF_RECORD_TIME By popular request, provide means to log a timestamp along with the counter overflow event. Signed-off-by: Peter Zijlstra Cc: Paul Mackerras Cc: Corey Ashford LKML-Reference: <20090406094518.024173282@chello.nl> Signed-off-by: Ingo Molnar --- include/linux/perf_counter.h | 2 ++ kernel/perf_counter.c | 14 ++++++++++++++ 2 files changed, 16 insertions(+) diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h index ca2d4df29e0c..928a7fae0961 100644 --- a/include/linux/perf_counter.h +++ b/include/linux/perf_counter.h @@ -102,6 +102,7 @@ enum perf_counter_record_format { PERF_RECORD_TID = 1U << 1, PERF_RECORD_GROUP = 1U << 2, PERF_RECORD_CALLCHAIN = 1U << 3, + PERF_RECORD_TIME = 1U << 4, }; /* @@ -221,6 +222,7 @@ enum perf_event_type { __PERF_EVENT_TID = PERF_RECORD_TID, __PERF_EVENT_GROUP = PERF_RECORD_GROUP, __PERF_EVENT_CALLCHAIN = PERF_RECORD_CALLCHAIN, + __PERF_EVENT_TIME = PERF_RECORD_TIME, }; #ifdef __KERNEL__ diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index c841563de043..19990d1f0215 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1826,6 +1826,7 @@ static void perf_counter_output(struct perf_counter *counter, } group_entry; struct perf_callchain_entry *callchain = NULL; int callchain_size = 0; + u64 time; header.type = PERF_EVENT_COUNTER_OVERFLOW; header.size = sizeof(header); @@ -1862,6 +1863,16 @@ static void perf_counter_output(struct perf_counter *counter, } } + if (record_type & PERF_RECORD_TIME) { + /* + * Maybe do better on x86 and provide cpu_clock_nmi() + */ + time = sched_clock(); + + header.type |= __PERF_EVENT_TIME; + header.size += sizeof(u64); + } + ret = perf_output_begin(&handle, counter, header.size, nmi); if (ret) return; @@ -1895,6 +1906,9 @@ static void perf_counter_output(struct perf_counter *counter, if (callchain) perf_output_copy(&handle, callchain, callchain_size); + if (record_type & PERF_RECORD_TIME) + perf_output_put(&handle, time); + perf_output_end(&handle); }