f0c86a2bae
In perf/Documentation/perf-stat.txt, for "--td-level" the default "0" means
the max level that the current hardware support.
So we need initialize the stat_config.topdown_level to TOPDOWN_MAX_LEVEL
when “--td-level=0” or no “--td-level” option. Otherwise, for the
hardware with a max level is 2, the 2nd level metrics disappear for raw
events in this case.
The issue cannot be observed for the perf stat default or "--topdown"
options. This commit fixes the raw events issue and removes the
duplicated code for the perf stat default.
Before:
# ./perf stat -e "cpu-clock,context-switches,cpu-migrations,page-faults,instructions,cycles,ref-cycles,branches,branch-misses,{slots,topdown-retiring,topdown-bad-spec,topdown-fe-bound,topdown-be-bound,topdown-heavy-ops,topdown-br-mispredict,topdown-fetch-lat,topdown-mem-bound}" sleep 1
Performance counter stats for 'sleep 1':
1.03 msec cpu-clock # 0.001 CPUs utilized
1 context-switches # 966.216 /sec
0 cpu-migrations # 0.000 /sec
60 page-faults # 57.973 K/sec
1,132,112 instructions # 1.41 insn per cycle
803,872 cycles # 0.777 GHz
1,909,120 ref-cycles # 1.845 G/sec
236,634 branches # 228.640 M/sec
6,367 branch-misses # 2.69% of all branches
4,823,232 slots # 4.660 G/sec
1,210,536 topdown-retiring # 25.1% Retiring
699,841 topdown-bad-spec # 14.5% Bad Speculation
1,777,975 topdown-fe-bound # 36.9% Frontend Bound
1,134,878 topdown-be-bound # 23.5% Backend Bound
189,146 topdown-heavy-ops # 182.756 M/sec
662,012 topdown-br-mispredict # 639.647 M/sec
1,097,048 topdown-fetch-lat # 1.060 G/sec
416,121 topdown-mem-bound # 402.063 M/sec
1.002423690 seconds time elapsed
0.002494000 seconds user
0.000000000 seconds sys
After:
# ./perf stat -e "cpu-clock,context-switches,cpu-migrations,page-faults,instructions,cycles,ref-cycles,branches,branch-misses,{slots,topdown-retiring,topdown-bad-spec,topdown-fe-bound,topdown-be-bound,topdown-heavy-ops,topdown-br-mispredict,topdown-fetch-lat,topdown-mem-bound}" sleep 1
Performance counter stats for 'sleep 1':
1.13 msec cpu-clock # 0.001 CPUs utilized
1 context-switches # 882.128 /sec
0 cpu-migrations # 0.000 /sec
61 page-faults # 53.810 K/sec
1,137,612 instructions # 1.29 insn per cycle
881,477 cycles # 0.778 GHz
2,093,496 ref-cycles # 1.847 G/sec
236,356 branches # 208.496 M/sec
7,090 branch-misses # 3.00% of all branches
5,288,862 slots # 4.665 G/sec
1,223,697 topdown-retiring # 23.1% Retiring
767,403 topdown-bad-spec # 14.5% Bad Speculation
2,053,322 topdown-fe-bound # 38.8% Frontend Bound
1,244,438 topdown-be-bound # 23.5% Backend Bound
186,665 topdown-heavy-ops # 3.5% Heavy Operations # 19.6% Light Operations
725,922 topdown-br-mispredict # 13.7% Branch Mispredict # 0.8% Machine Clears
1,327,400 topdown-fetch-lat # 25.1% Fetch Latency # 13.7% Fetch Bandwidth
497,775 topdown-mem-bound # 9.4% Memory Bound # 14.1% Core Bound
1.002701530 seconds time elapsed
0.002744000 seconds user
0.000000000 seconds sys
Fixes: 63e39aa6ae ("perf stat: Support L2 Topdown events")
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Xing Zhengjun <zhengjun.xing@linux.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: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220826140057.3289401-1-zhengjun.xing@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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.