[PATCH] ARM: perf: return -EOPNOTSUPP if requested mode exclusion is unavailable

Will Deacon will.deacon at arm.com
Fri Jun 15 06:41:51 EDT 2012

We currently return -EPERM if the user requests mode exclusion that is
not supported by the CPU. This looks pretty confusing from userspace
and is inconsistent with other architectures (ppc, x86).

This patch returns -EOPNOTSUPP instead.

Signed-off-by: Will Deacon <will.deacon at arm.com>
 arch/arm/kernel/perf_event.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 186c8cb..a02eada 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -503,7 +503,7 @@ __hw_perf_event_init(struct perf_event *event)
 	     event_requires_mode_exclusion(&event->attr)) {
 		pr_debug("ARM performance counters do not support "
 			 "mode exclusion\n");
-		return -EPERM;
+		return -EOPNOTSUPP;

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