From: Zhengjun Xing zhengjun.xing@linux.intel.com
commit 91c9923a473a694eb1c5c01ab778a77114969707 upstream.
This bug happened on hybrid systems when both cpu_core and cpu_atom have the same event name such as "UOPS_RETIRED.MS" while their event terms are different, then during perf stat, the event for cpu_atom will parse fail and then no output for cpu_atom.
UOPS_RETIRED.MS -> cpu_core/period=0x1e8483,umask=0x4,event=0xc2,frontend=0x8/ UOPS_RETIRED.MS -> cpu_atom/period=0x1e8483,umask=0x1,event=0xc2/
It is because event terms in the "head" of parse_events_multi_pmu_add will be changed to event terms for cpu_core after parsing UOPS_RETIRED.MS for cpu_core, then when parsing the same event for cpu_atom, it still uses the event terms for cpu_core, but event terms for cpu_atom are different with cpu_core, the event parses for cpu_atom will fail. This patch fixes it, the event terms should be parsed from the original event.
This patch can work for the hybrid systems that have the same event in more than 2 PMUs. It also can work in non-hybrid systems.
Before:
# perf stat -v -e UOPS_RETIRED.MS -a sleep 1
Using CPUID GenuineIntel-6-97-1 UOPS_RETIRED.MS -> cpu_core/period=0x1e8483,umask=0x4,event=0xc2,frontend=0x8/ Control descriptor is not initialized UOPS_RETIRED.MS: 2737845 16068518485 16068518485
Performance counter stats for 'system wide':
2,737,845 cpu_core/UOPS_RETIRED.MS/
1.002553850 seconds time elapsed
After:
# perf stat -v -e UOPS_RETIRED.MS -a sleep 1
Using CPUID GenuineIntel-6-97-1 UOPS_RETIRED.MS -> cpu_core/period=0x1e8483,umask=0x4,event=0xc2,frontend=0x8/ UOPS_RETIRED.MS -> cpu_atom/period=0x1e8483,umask=0x1,event=0xc2/ Control descriptor is not initialized UOPS_RETIRED.MS: 1977555 16076950711 16076950711 UOPS_RETIRED.MS: 568684 8038694234 8038694234
Performance counter stats for 'system wide':
1,977,555 cpu_core/UOPS_RETIRED.MS/ 568,684 cpu_atom/UOPS_RETIRED.MS/
1.004758259 seconds time elapsed
Fixes: fb0811535e92c6c1 ("perf parse-events: Allow config on kernel PMU events") Reviewed-by: Kan Liang kan.liang@linux.intel.com Signed-off-by: Zhengjun Xing zhengjun.xing@linux.intel.com Cc: Adrian Hunter adrian.hunter@intel.com Cc: Alexander Shishkin alexander.shishkin@intel.com Cc: Andi Kleen ak@linux.intel.com Cc: Ian Rogers irogers@google.com Cc: Ingo Molnar mingo@redhat.com Cc: Jiri Olsa jolsa@kernel.org Cc: Peter Zijlstra peterz@infradead.org Link: https://lore.kernel.org/r/20220307151627.30049-1-zhengjun.xing@linux.intel.c... Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/perf/util/parse-events.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -1648,6 +1648,7 @@ int parse_events_multi_pmu_add(struct pa { struct parse_events_term *term; struct list_head *list = NULL; + struct list_head *orig_head = NULL; struct perf_pmu *pmu = NULL; int ok = 0; char *config; @@ -1674,7 +1675,6 @@ int parse_events_multi_pmu_add(struct pa } list_add_tail(&term->list, head);
- /* Add it for all PMUs that support the alias */ list = malloc(sizeof(struct list_head)); if (!list) @@ -1687,13 +1687,15 @@ int parse_events_multi_pmu_add(struct pa
list_for_each_entry(alias, &pmu->aliases, list) { if (!strcasecmp(alias->name, str)) { + parse_events_copy_term_list(head, &orig_head); if (!parse_events_add_pmu(parse_state, list, - pmu->name, head, + pmu->name, orig_head, true, true)) { pr_debug("%s -> %s/%s/\n", str, pmu->name, alias->str); ok++; } + parse_events_terms__delete(orig_head); } } }