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 <[email protected]>
Date: Fri Jan 30 12:31:06 2015 +0200
perf: Add a pmu capability for "exclusive" events
Signed-off-by: Alexander Shishkin <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Kaixu Xia <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Robert Richter <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Vince Weaver <[email protected]>
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