perf stat: Support L2 Topdown events
The TMA method level 2 metrics is supported from the Intel Sapphire Rapids server, which expose four L2 Topdown metrics events to user space. There are eight L2 events in total. The other four L2 Topdown metrics events are calculated from the corresponding L1 and the exposed L2 events. Now, the --topdown prints the complete top-down metrics that supported by the CPU. For the Intel Sapphire Rapids server, there are 4 L1 events and 8 L2 events displyed in one line. Add a new option, --td-level, to display the top-down statistics that equal to or lower than the input level. The L2 event is marked only when both its L1 parent event and itself crosse the threshold. Here is an example: $ perf stat --topdown --td-level=2 --no-metric-only sleep 1 Topdown accuracy may decrease when measuring long periods. Please print the result regularly, e.g. -I1000 Performance counter stats for 'sleep 1': 16,734,390 slots 2,100,001 topdown-retiring # 12.6% retiring 2,034,376 topdown-bad-spec # 12.3% bad speculation 4,003,128 topdown-fe-bound # 24.1% frontend bound 328,125 topdown-heavy-ops # 2.0% heavy operations # 10.6% light operations 1,968,751 topdown-br-mispredict # 11.9% branch mispredict # 0.4% machine clears 2,953,127 topdown-fetch-lat # 17.8% fetch latency # 6.3% fetch bandwidth 5,906,255 topdown-mem-bound # 35.6% memory bound # 15.4% core bound Signed-off-by:Kan Liang <kan.liang@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/1612296553-21962-9-git-send-email-kan.liang@linux.intel.com Signed-off-by:
Arnaldo Carvalho de Melo <acme@redhat.com>
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c7444297