diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/ring_buffer.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 232f00f273cb..725c416085e3 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -493,6 +493,20 @@ int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event, rb->aux_pages[rb->aux_nr_pages] = page_address(page++); } + /* + * In overwrite mode, PMUs that don't support SG may not handle more + * than one contiguous allocation, since they rely on PMI to do double + * buffering. In this case, the entire buffer has to be one contiguous + * chunk. + */ + if ((event->pmu->capabilities & PERF_PMU_CAP_AUX_NO_SG) && + overwrite) { + struct page *page = virt_to_page(rb->aux_pages[0]); + + if (page_private(page) != max_order) + goto out; + } + rb->aux_priv = event->pmu->setup_aux(event->cpu, rb->aux_pages, nr_pages, overwrite); if (!rb->aux_priv) |