021b462a51
We should support this because it would allow easily to collect metrics for different threads in applications. Original patch from posted by Jin Yao in here [1]. 1. Current output, for example: root@skl:/tmp# perf stat --per-thread -p 21623 ^C Performance counter stats for process id '21623': vmstat-21623 0.517479 task-clock (msec) # 0.000 CPUs utilized vmstat-21623 1 context-switches vmstat-21623 0 cpu-migrations vmstat-21623 0 page-faults vmstat-21623 461,306 cycles vmstat-21623 630,724 instructions vmstat-21623 136,265 branches vmstat-21623 2,520 branch-misses 1.444020756 seconds time elapsed root@skl:/tmp# perf stat --per-thread --metrics ipc -p 21623 ^C Performance counter stats for process id '21623': vmstat-21623 631,185 inst_retired.any vmstat-21623 605,893 cpu_clk_unhalted.thread 1.415679293 seconds time elapsed 2. With this patch, the result would be: root@skl:/tmp# perf stat --per-thread -p 21623 ^C Performance counter stats for process id '21623': vmstat-21623 0.533759 task-clock (msec) # 0.000 CPUs utilized vmstat-21623 1 context-switches # 0.002 M/sec vmstat-21623 0 cpu-migrations # 0.000 K/sec vmstat-21623 0 page-faults # 0.000 K/sec vmstat-21623 473,896 cycles # 0.888 GHz vmstat-21623 631,072 instructions # 1.33 insn per cycle vmstat-21623 136,307 branches # 255.372 M/sec vmstat-21623 2,524 branch-misses # 1.85% of all branches 1.544862861 seconds time elapsed root@skl:/tmp# perf stat --per-thread --metrics ipc -p 21623 ^C Performance counter stats for process id '21623': vmstat-21623 1,259,104 inst_retired.any # 1.2 IPC vmstat-21623 1,056,756 cpu_clk_unhalted.thread 2.040954502 seconds time elapsed [1] https://marc.info/?l=linux-kernel&m=150777054620511&w=2 Originally-from: Jin Yao <yao.jin@linux.intel.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Changbin Du <changbin.du@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-tr8ntktxmy4qc5769ajg5u6c@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>