Commit-ID: 673d659f5c5918b7ddbafebf1f129c9eb82973b4 Gitweb: http://git.kernel.org/tip/673d659f5c5918b7ddbafebf1f129c9eb82973b4 Author: Alexander Yarygin <yarygin@xxxxxxxxxxxxxxxxxx> AuthorDate: Fri, 3 Oct 2014 18:40:12 +0400 Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> CommitDate: Wed, 15 Oct 2014 17:39:03 -0300 perf kvm stat live: Enable events copying Process of analyzing events caused by 2 functions: mmap_read() and finished_round(). During mmap_read(), perf receives events from shared memory, queues their pointers for further processing in finished_round() and notifies the kernel that the events have been processed. By the time when finished_round() is invoked, queued events can be overwritten by the kernel, so the finished_round() occurs on potentially corrupted memory. Since there is no place where the event can be safely consumed, let's copy events when queueing. Signed-off-by: Alexander Yarygin <yarygin@xxxxxxxxxxxxxxxxxx> Cc: Christian Borntraeger <borntraeger@xxxxxxxxxx> Cc: David Ahern <dsahern@xxxxxxxxx> Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Mike Galbraith <efault@xxxxxx> Cc: Namhyung Kim <namhyung.kim@xxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Cc: Stephane Eranian <eranian@xxxxxxxxxx> Link: http://lkml.kernel.org/r/1412347212-28237-3-git-send-email-yarygin@xxxxxxxxxxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/perf/builtin-kvm.c | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c index ef9fc15..b65eb050 100644 --- a/tools/perf/builtin-kvm.c +++ b/tools/perf/builtin-kvm.c @@ -1358,6 +1358,7 @@ static int kvm_events_live(struct perf_kvm_stat *kvm, } kvm->session->evlist = kvm->evlist; perf_session__set_id_hdr_size(kvm->session); + ordered_events__set_copy_on_queue(&kvm->session->ordered_events, true); machine__synthesize_threads(&kvm->session->machines.host, &kvm->opts.target, kvm->evlist->threads, false); err = kvm_live_open_events(kvm); -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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