6.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: Athira Rajeev <[email protected]> [ Upstream commit 789d22d77879eabb042627f6627cdb62787bc142 ] perf trace record fails some cases in powerpc # perf test "perf trace record and replay" 128: perf trace record and replay : FAILED! # perf trace record sleep 1 # echo $? 32 This is happening because of non-zero err value from auxtrace_record__init() function. static int record__auxtrace_init(struct record *rec) { int err; if ((rec->opts.auxtrace_snapshot_opts || rec->opts.auxtrace_sample_opts) && record__threads_enabled(rec)) { pr_err("AUX area tracing options are not available in parallel streaming mode.\n"); return -EINVAL; } if (!rec->itr) { rec->itr = auxtrace_record__init(rec->evlist, &err); if (err) return err; } Here "int err" is not initialised. The code expects "err" to be set from auxtrace_record__init() function. Update auxtrace_record__init() in arch/powerpc/util/auxtrace.c to clear err value in the beginning. - Clear err value in beginning of function. Any fail later will set appropriate return code to err. - Even if we haven't found any event for auxtrace, perf record should continue for other events. NULL return will indicate that there is no auxtrace record initialized. - Not having "err" set here will affect monitoring of other events also because perf record will fail seeing random value in err. Set err to -EINVAL before invoking auxtrace_record__init() in builtin-record.c With the fix, # perf trace record sleep 1 [ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 0.033 MB perf.data (228 samples) ] Fixes: 1dbfaf94cf66ec4b ("perf powerpc: Add basic CONFIG_AUXTRACE support for VPA pmu on powerpc") Reviewed-by: Adrian Hunter <[email protected]> Signed-off-by: Athira Rajeev <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Athira Rajeev <[email protected]> Cc: Hari Bathini <[email protected]> Cc: Ian Rogers <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: [email protected] Cc: Madhavan Srinivasan <[email protected]> Cc: Michael Petlan <[email protected]> Cc: Shivani Nittor <[email protected]> Cc: Tanushree Shah <[email protected]> Cc: Tejas Manhas <[email protected]> Cc: Thomas Richter <[email protected]> Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- tools/perf/arch/powerpc/util/auxtrace.c | 6 ++++++ tools/perf/builtin-record.c | 1 + 2 files changed, 7 insertions(+) diff --git a/tools/perf/arch/powerpc/util/auxtrace.c b/tools/perf/arch/powerpc/util/auxtrace.c index 62c6f67f1bbe66..57f2910c0b0198 100644 --- a/tools/perf/arch/powerpc/util/auxtrace.c +++ b/tools/perf/arch/powerpc/util/auxtrace.c @@ -70,6 +70,12 @@ struct auxtrace_record *auxtrace_record__init(struct evlist *evlist, struct evsel *pos; int found = 0; + /* + * Set err value to zero here. Any fail later + * will set appropriate return code to err. + */ + *err = 0; + evlist__for_each_entry(evlist, pos) { if (strstarts(pos->name, "vpa_dtl")) { found = 1; diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index b1fb87016d5aa9..2563ef66a4d946 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -867,6 +867,7 @@ static int record__auxtrace_init(struct record *rec) } if (!rec->itr) { + err = -EINVAL; rec->itr = auxtrace_record__init(rec->evlist, &err); if (err) return err; -- 2.53.0
