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| author | Jani Nikula <jani.nikula@intel.com> | 2018-11-20 13:14:08 +0200 |
|---|---|---|
| committer | Jani Nikula <jani.nikula@intel.com> | 2018-11-20 13:14:08 +0200 |
| commit | 2ac5e38ea4203852d6e99edd3cf11f044b0a409f (patch) | |
| tree | 1ef02da98d56309368ad2b6a4e492bafe5bb4faf /kernel/events/ring_buffer.c | |
| parent | f48cc647f3e196a3179d695d3c2d56c13e9dec98 (diff) | |
| parent | 9235dd441af43599b9cdcce599a3da4083fcad3c (diff) | |
| download | talos-op-linux-2ac5e38ea4203852d6e99edd3cf11f044b0a409f.tar.gz talos-op-linux-2ac5e38ea4203852d6e99edd3cf11f044b0a409f.zip | |
Merge drm/drm-next into drm-intel-next-queued
Pull in v4.20-rc3 via drm-next.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Diffstat (limited to 'kernel/events/ring_buffer.c')
| -rw-r--r-- | kernel/events/ring_buffer.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 5d3cf407e374..4a9937076331 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -459,10 +459,20 @@ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size) if (size || handle->aux_flags) { /* * Only send RECORD_AUX if we have something useful to communicate + * + * Note: the OVERWRITE records by themselves are not considered + * useful, as they don't communicate any *new* information, + * aside from the short-lived offset, that becomes history at + * the next event sched-in and therefore isn't useful. + * The userspace that needs to copy out AUX data in overwrite + * mode should know to use user_page::aux_head for the actual + * offset. So, from now on we don't output AUX records that + * have *only* OVERWRITE flag set. */ - perf_event_aux_event(handle->event, aux_head, size, - handle->aux_flags); + if (handle->aux_flags & ~(u64)PERF_AUX_FLAG_OVERWRITE) + perf_event_aux_event(handle->event, aux_head, size, + handle->aux_flags); } rb->user_page->aux_head = rb->aux_head; |
