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perf vendor events: Update PMC used in PM_RUN_INST_CMPL event for power10 platform 

[ Upstream commit 3f8b6e5b11 ]

The CPI_STALL_RATIO metric group can be used to present the high
level CPI stall breakdown metrics in powerpc, which will show:

- DISPATCH_STALL_CPI ( Dispatch stall cycles per insn )
- ISSUE_STALL_CPI ( Issue stall cycles per insn )
- EXECUTION_STALL_CPI ( Execution stall cycles per insn )
- COMPLETION_STALL_CPI ( Completion stall cycles per insn )

Commit cf26e043c2 ("perf vendor events power10: Add JSON
metric events to present CPI stall cycles in powerpc)" which added
the CPI_STALL_RATIO metric group, also modified
the PMC value used in PM_RUN_INST_CMPL event from PMC4 to PMC5,
to avoid multiplexing of events.
But that got revert in recent changes. Fix this issue by changing
back the PMC value used in PM_RUN_INST_CMPL to PMC5.

Result with the fix:

 ./perf stat --metric-no-group -M CPI_STALL_RATIO <workload>

 Performance counter stats for 'workload':

        68,745,426      PM_CMPL_STALL                    #     0.21 COMPLETION_STALL_CPI
         7,692,827      PM_ISSUE_STALL                   #     0.02 ISSUE_STALL_CPI
       322,638,223      PM_RUN_INST_CMPL                 #     0.05 DISPATCH_STALL_CPI
                                                  #     0.48 EXECUTION_STALL_CPI
        16,858,553      PM_DISP_STALL_CYC
       153,880,133      PM_EXEC_STALL

       0.089774592 seconds time elapsed

"--metric-no-group" is used for forcing PM_RUN_INST_CMPL to be scheduled
in all group for more accuracy.

Fixes: 7d473f475b ("perf vendor events: Move JSON/events to appropriate files for power10 platform")
Reported-by: Disha Goel <disgoel@linux.vnet.ibm.com>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Disha Goel<disgoel@linux.ibm.com>
Cc: maddy@linux.ibm.com
Link: https://lore.kernel.org/r/20231016143110.244255-1-kjain@linux.ibm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Kajol Jain 2023-10-16 20:01:10 +05:30 committed by Greg Kroah-Hartman
parent ed905e38c0
commit 056a838504
1 changed files with 1 additions and 1 deletions
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2
tools/perf/pmu-events/arch/powerpc/power10/pmc.json
View File

@ -190,7 +190,7 @@
"BriefDescription": "Threshold counter exceeded a value of 128."
},
{
"EventCode": "0x400FA",
"EventCode": "0x500FA",
"EventName": "PM_RUN_INST_CMPL",
"BriefDescription": "PowerPC instruction completed while the run latch is set."
}