• Kajol Jain's avatar
    perf vendor events: Update PMC used in PM_RUN_INST_CMPL event for power10 platform · 3f8b6e5b
    Kajol Jain authored
    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 cf26e043 ("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: 7d473f47 ("perf vendor events: Move JSON/events to appropriate files for power10 platform")
    Reported-by: default avatarDisha Goel <disgoel@linux.vnet.ibm.com>
    Signed-off-by: default avatarKajol Jain <kjain@linux.ibm.com>
    Reviewed-by: default avatarAthira 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.comSigned-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
    3f8b6e5b
pmc.json 6.31 KB