perf lock contention: Add -G/--cgroup-filter option

The -G/--cgroup-filter is to limit lock contention collection on the
tasks in the specific cgroups only.

  $ sudo ./perf lock con -abt -G /user.slice/.../vte-spawn-52221fb8-b33f-4a52-b5c3-e35d1e6fc0e0.scope \
    ./perf bench sched messaging
  # Running 'sched/messaging' benchmark:
  # 20 sender and receiver processes per group
  # 10 groups == 400 processes run

       Total time: 0.174 [sec]
   contended   total wait     max wait     avg wait          pid   comm

           4    114.45 us     60.06 us     28.61 us       214847   sched-messaging
           2    111.40 us     60.84 us     55.70 us       214848   sched-messaging
           2    106.09 us     59.42 us     53.04 us       214837   sched-messaging
           1     81.70 us     81.70 us     81.70 us       214709   sched-messaging
          68     78.44 us      6.83 us      1.15 us       214633   sched-messaging
          69     73.71 us      2.69 us      1.07 us       214632   sched-messaging
           4     72.62 us     60.83 us     18.15 us       214850   sched-messaging
           2     71.75 us     67.60 us     35.88 us       214840   sched-messaging
           2     69.29 us     67.53 us     34.65 us       214804   sched-messaging
           2     69.00 us     68.23 us     34.50 us       214826   sched-messaging
  ...

Export cgroup__new() function as it's needed from outside.

Reviewed-by: Ian Rogers <[email protected]>
Signed-off-by: Namhyung Kim <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Hao Luo <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Song Liu <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

0 files changed, 0 insertions, 0 deletions