diff options
| -rw-r--r-- | tools/perf/util/evlist.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index dc1dc2c181ef..6b58a47a79ec 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -634,11 +634,18 @@ static struct perf_evsel *perf_evlist__event2evsel(struct perf_evlist *evlist, union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx) { struct perf_mmap *md = &evlist->mmap[idx]; - u64 head = perf_mmap__read_head(md); + u64 head; u64 old = md->prev; unsigned char *data = md->base + page_size; union perf_event *event = NULL; + /* + * Check if event was unmapped due to a POLLHUP/POLLERR. + */ + if (!atomic_read(&md->refcnt)) + return NULL; + + head = perf_mmap__read_head(md); if (evlist->overwrite) { /* * If we're further behind than half the buffer, there's a chance |