diff options
authorHendrik Brueckner <brueckner@linux.vnet.ibm.com>2017-06-20 12:26:39 +0200
committerIngo Molnar <mingo@kernel.org>2017-06-21 11:58:30 +0200
commit8a1898db51a3390241cd5fae267dc8aaa9db0f8b (patch)
parent9705596d08ac87c18aee32cc97f2783b7d14624e (diff)
perf/aux: Correct return code of rb_alloc_aux() if !has_aux(ev)
If the event for which an AUX area is about to be allocated, does not support setting up an AUX area, rb_alloc_aux() return -ENOTSUPP. This error condition is being returned unfiltered to the user space, and, for example, the perf tools fails with: failed to mmap with 524 (INTERNAL ERROR: strerror_r(524, 0x3fff497a1c8, 512)=22) This error can be easily seen with "perf record -m 128,256 -e cpu-clock". The 524 error code maps to -ENOTSUPP (in rb_alloc_aux()). The -ENOTSUPP error code shall be only used within the kernel. So the correct error code would then be -EOPNOTSUPP. With this commit, the perf tool then reports: failed to mmap with 95 (Operation not supported) which is more clear. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pu Hou <bjhoupu@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com> Cc: acme@kernel.org Cc: linux-s390@vger.kernel.org Link: http://lkml.kernel.org/r/1497954399-6355-1-git-send-email-brueckner@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 2831480c63a2..ee97196bb151 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -580,7 +580,7 @@ int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event,
int ret = -ENOMEM, max_order = 0;
if (!has_aux(event))
- return -ENOTSUPP;
+ return -EOPNOTSUPP;
if (event->pmu->capabilities & PERF_PMU_CAP_AUX_NO_SG) {