From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758695AbcIHUsa (ORCPT ); Thu, 8 Sep 2016 16:48:30 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:48792 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757993AbcIHUqj (ORCPT ); Thu, 8 Sep 2016 16:46:39 -0400 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Mark Rutland , Alexander Shishkin , Peter Zijlstra , Will Deacon , Arnaldo Carvalho de Melo Subject: [PATCH 10/12] perf evlist: Only open events on CPUs an evsel permits Date: Thu, 8 Sep 2016 17:46:19 -0300 Message-Id: <1473367581-5996-11-git-send-email-acme@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1473367581-5996-1-git-send-email-acme@kernel.org> References: <1473367581-5996-1-git-send-email-acme@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mark Rutland In systems with heterogeneous CPU PMUs, it's possible for each evsel to cover a distinct set of CPUs, and hence the cpu_map associated with each evsel may have a distinct idx<->id mapping. Any of these may be distinct from the evlist's cpu map. Events can be tied to the same fd so long as they use the same per-cpu ringbuffer (i.e. so long as they are on the same CPU). To acquire the correct FDs, we must compare the Linux logical IDs rather than the evsel or evlist indices. This path adds logic to perf_evlist__mmap_per_evsel to handle this, translating IDs as required. As PMUs may cover a subset of CPUs from the evlist, we skip the CPUs a PMU cannot handle. Without this patch, perf record may try to mmap erroneous FDs on heterogeneous systems, and will bail out early rather than running the workload. Signed-off-by: Mark Rutland Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Mark Rutland Cc: Peter Zijlstra Cc: Will Deacon Link: http://lkml.kernel.org/r/1473330112-28528-7-git-send-email-mark.rutland@arm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/evlist.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 097b3ed77fdd..ea34c5a32c11 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1032,16 +1032,18 @@ perf_evlist__should_poll(struct perf_evlist *evlist __maybe_unused, } static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx, - struct mmap_params *mp, int cpu, + struct mmap_params *mp, int cpu_idx, int thread, int *_output, int *_output_backward) { struct perf_evsel *evsel; int revent; + int evlist_cpu = cpu_map__cpu(evlist->cpus, cpu_idx); evlist__for_each_entry(evlist, evsel) { struct perf_mmap *maps = evlist->mmap; int *output = _output; int fd; + int cpu; if (evsel->attr.write_backward) { output = _output_backward; @@ -1060,6 +1062,10 @@ static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx, if (evsel->system_wide && thread) continue; + cpu = cpu_map__idx(evsel->cpus, evlist_cpu); + if (cpu == -1) + continue; + fd = FD(evsel, cpu, thread); if (*output == -1) { -- 2.7.4