Re: [PATCH] perf vendor events: Update datasource event name to fix duplicate events
From: Ian Rogers <irogers@google.com>
Date: 2023-12-04 20:14:02
Also in:
linux-perf-users
On Thu, Nov 23, 2023 at 8:01 AM Athira Rajeev [off-list ref] wrote:
Running "perf list" on powerpc fails with segfault
as below:
./perf list
Segmentation fault (core dumped)
This happens because of duplicate events in the json list.
The powerpc Json event list contains some event with same
event name, but different event code. They are:
- PM_INST_FROM_L3MISS (Present in datasource and frontend)
- PM_MRK_DATA_FROM_L2MISS (Present in datasource and marked)
- PM_MRK_INST_FROM_L3MISS (Present in datasource and marked)
- PM_MRK_DATA_FROM_L3MISS (Present in datasource and marked)
pmu_events_table__num_events uses the value from
table_pmu->num_entries which includes duplicate events as
well. This causes issue during "perf list" and results in
segmentation fault.
Since both event codes are valid, append _DSRC to the Data
Source events (datasource.json), so that they would have a
unique name. Also add PM_DATA_FROM_L2MISS_DSRC and
PM_DATA_FROM_L3MISS_DSRC events. With the fix, perf list
works as expected.
Fixes: fc1435807533 ("perf vendor events power10: Update JSON/events")
Signed-off-by: Athira Rajeev <redacted>Given duplicate events creates broken pmu-events.c we should capture that as an exception in jevents.py. That way a JEVENTS_ARCH=all build will fail if any vendor/architecture would break in this way. We should also add JEVENTS_ARCH=all to tools/perf/tests/make. Athira, do you want to look at doing this? Thanks, Ian
quoted hunk ↗ jump to hunk
--- .../arch/powerpc/power10/datasource.json | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-)diff --git a/tools/perf/pmu-events/arch/powerpc/power10/datasource.json b/tools/perf/pmu-events/arch/powerpc/power10/datasource.json index 6b0356f2d301..0eeaaf1a95b8 100644 --- a/tools/perf/pmu-events/arch/powerpc/power10/datasource.json +++ b/tools/perf/pmu-events/arch/powerpc/power10/datasource.json@@ -99,6 +99,11 @@ "EventName": "PM_INST_FROM_L2MISS", "BriefDescription": "The processor's instruction cache was reloaded from a source beyond the local core's L2 due to a demand miss." }, + { + "EventCode": "0x0003C0000000C040", + "EventName": "PM_DATA_FROM_L2MISS_DSRC", + "BriefDescription": "The processor's L1 data cache was reloaded from a source beyond the local core's L2 due to a demand miss." + }, { "EventCode": "0x000380000010C040", "EventName": "PM_INST_FROM_L2MISS_ALL",@@ -161,9 +166,14 @@ }, { "EventCode": "0x000780000000C040", - "EventName": "PM_INST_FROM_L3MISS", + "EventName": "PM_INST_FROM_L3MISS_DSRC", "BriefDescription": "The processor's instruction cache was reloaded from beyond the local core's L3 due to a demand miss." }, + { + "EventCode": "0x0007C0000000C040", + "EventName": "PM_DATA_FROM_L3MISS_DSRC", + "BriefDescription": "The processor's L1 data cache was reloaded from beyond the local core's L3 due to a demand miss." + }, { "EventCode": "0x000780000010C040", "EventName": "PM_INST_FROM_L3MISS_ALL",@@ -981,7 +991,7 @@ }, { "EventCode": "0x0003C0000000C142", - "EventName": "PM_MRK_DATA_FROM_L2MISS", + "EventName": "PM_MRK_DATA_FROM_L2MISS_DSRC", "BriefDescription": "The processor's L1 data cache was reloaded from a source beyond the local core's L2 due to a demand miss for a marked instruction." }, {@@ -1046,12 +1056,12 @@ }, { "EventCode": "0x000780000000C142", - "EventName": "PM_MRK_INST_FROM_L3MISS", + "EventName": "PM_MRK_INST_FROM_L3MISS_DSRC", "BriefDescription": "The processor's instruction cache was reloaded from beyond the local core's L3 due to a demand miss for a marked instruction." }, { "EventCode": "0x0007C0000000C142", - "EventName": "PM_MRK_DATA_FROM_L3MISS", + "EventName": "PM_MRK_DATA_FROM_L3MISS_DSRC", "BriefDescription": "The processor's L1 data cache was reloaded from beyond the local core's L3 due to a demand miss for a marked instruction." }, { --2.39.3