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| author | Hendrik Brueckner <brueckner@linux.vnet.ibm.com> | 2017-06-20 12:26:39 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-06-21 11:58:30 +0200 |
| commit | 8a1898db51a3390241cd5fae267dc8aaa9db0f8b (patch) | |
| tree | af5992171da843c26f3a072e1fab03b261adf9fb /kernel | |
| parent | 9705596d08ac87c18aee32cc97f2783b7d14624e (diff) | |
| download | linux-8a1898db51a3390241cd5fae267dc8aaa9db0f8b.tar.bz2 | |
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>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/ring_buffer.c | 2 |
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) { /* |