From 4ab8455f8bd83298bf7f67ab9357e3b1cc765c7d Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 3 Oct 2018 23:20:52 +0200 Subject: [PATCH] perf evsel: Store ids for events with their own cpus perf_event__synthesize_event_update_cpus John reported crash when recording on an event under PMU with cpumask defined: root@localhost:~# ./perf_debug_ record -e armv8_pmuv3_0/br_mis_pred/ sleep 1 perf: Segmentation fault Obtained 9 stack frames. ./perf_debug_() [0x4c5ef8] [0xffff82ba267c] ./perf_debug_() [0x4bc5a8] ./perf_debug_() [0x419550] ./perf_debug_() [0x41a928] ./perf_debug_() [0x472f58] ./perf_debug_() [0x473210] ./perf_debug_() [0x4070f4] /lib/aarch64-linux-gnu/libc.so.6(__libc_start_main+0xe0) [0xffff8294c8a0] Segmentation fault (core dumped) We synthesize an update event that needs to touch the evsel id array, which is not defined at that time. Fixing this by forcing the id allocation for events with their own cpus. Reported-by: John Garry Signed-off-by: Jiri Olsa Tested-by: John Garry Cc: Alexander Shishkin Cc: Andi Kleen Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Cc: linuxarm@huawei.com Fixes: bfd8f72c2778 ("perf record: Synthesize unit/scale/... in event update") Link: http://lkml.kernel.org/r/20181003212052.GA32371@krava Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-report.c | 1 + tools/perf/util/evsel.c | 3 +++ 2 files changed, 4 insertions(+) diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index 76e12bcd1765..b2188e623e22 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -981,6 +981,7 @@ int cmd_report(int argc, const char **argv) .id_index = perf_event__process_id_index, .auxtrace_info = perf_event__process_auxtrace_info, .auxtrace = perf_event__process_auxtrace, + .event_update = perf_event__process_event_update, .feature = process_feature_event, .ordered_events = true, .ordering_requires_timestamps = true, diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 1a61628a1c12..e596ae358c4d 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -1089,6 +1089,9 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts, attr->exclude_user = 1; } + if (evsel->own_cpus) + evsel->attr.read_format |= PERF_FORMAT_ID; + /* * Apply event specific term settings, * it overloads any global configuration. -- 2.30.2