Linux 4.1 added the possibility of perf_event_open() returning EBUSY if an existing exclusive event controls the PMU. This was introduced by the following commit: commit bed5b25ad9c8a2f5d735ef0bc746ec870c01c1b0 Author: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Date: Fri Jan 30 12:31:06 2015 +0200 perf: Add a pmu capability for "exclusive" events Signed-off-by: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Kaixu Xia <kaixu.xia@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Mike Galbraith <efault@xxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Robert Richter <rric@xxxxxxxxxx> Cc: Stephane Eranian <eranian@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: acme@xxxxxxxxxxxxx Cc: adrian.hunter@xxxxxxxxx Cc: kan.liang@xxxxxxxxx Cc: markus.t.metzger@xxxxxxxxx Cc: mathieu.poirier@xxxxxxxxxx Signed-off-by: Vince Weaver <vincent.weaver@xxxxxxxxx> diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2 index b3cd93f..3d03786 100644 --- a/man2/perf_event_open.2 +++ b/man2/perf_event_open.2 @@ -2911,6 +2911,11 @@ the cgroup file descriptor in .I pid is not valid. .TP +.BR EBUSY " (since Linux 4.1)" +.\" bed5b25ad9c8a2f5d735ef0bc746ec870c01c1b0 +Returned if another event already has exclusive +access to the PMU. +.TP .B EFAULT Returned if the .I attr -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
