e2eb96ae62
[ Upstream commit 3f8b6e5b11192dacb721d2d28ea4589917f5e822 ]
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 cf26e043c2a9 ("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: 7d473f475b2a ("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>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.