From: Alexander Yarygin Date: Fri, 3 Oct 2014 14:40:12 +0000 (+0400) Subject: perf kvm stat live: Enable events copying X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=673d659f5c5918b7ddbafebf1f129c9eb82973b4;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git 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 Cc: Christian Borntraeger Cc: David Ahern Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Jiri Olsa Cc: Mike Galbraith Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1412347212-28237-3-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c index ef9fc15fbfbf..b65eb0507b38 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);