From f38b0dbb491a6987e198aa6b428db8692a6480f8 Mon Sep 17 00:00:00 2001 From: Kan Liang Date: Sun, 10 May 2015 15:13:14 -0400 Subject: perf/x86/intel: Introduce PERF_RECORD_LOST_SAMPLES After enlarging the PEBS interrupt threshold, there may be some mixed up PEBS samples which are discarded by the kernel. This patch makes the kernel emit a PERF_RECORD_LOST_SAMPLES record with the number of possible discarded records when it is impossible to demux the samples. It makes sure the user is not left in the dark about such discards. Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: acme@infradead.org Cc: eranian@google.com Link: http://lkml.kernel.org/r/1431285195-14269-8-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar --- include/uapi/linux/perf_event.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include/uapi/linux/perf_event.h') diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index c4622f1ce046..613ed9ad588f 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -802,6 +802,18 @@ enum perf_event_type { */ PERF_RECORD_ITRACE_START = 12, + /* + * Records the dropped/lost sample number. + * + * struct { + * struct perf_event_header header; + * + * u64 lost; + * struct sample_id sample_id; + * }; + */ + PERF_RECORD_LOST_SAMPLES = 13, + PERF_RECORD_MAX, /* non-ABI */ }; -- cgit v1.2.3