• Arnaldo Carvalho de Melo's avatar
    perf trace: Allow configuring default for perf_event_attr.inherit · d32de87e
    Arnaldo Carvalho de Melo authored
    I.f. if children should inherit the parent perf_event configuration,
    i.e. if we should trace children as well or just the parent.
    
    The default is to follow children, to disable this and have a behaviour
    similar to strace, set this config option or use the --no_inherit 'perf
    trace' option.
    
    E.g.:
    
    Default:
    
      # perf config trace.no_inherit
      # trace -e clone,*sleep time sleep 1
         0.000 time/21107 clone(clone_flags: CHILD_CLEARTID|CHILD_SETTID|0x11, newsp: 0, child_tidptr: 0x7f7b8f9ae810) = 21108 (time)
             ? time/21108  ... [continued]: clone()
         0.691 sleep/21108 nanosleep(rqtp: 0x7ffed01d0540, rmtp: 0                               ) = 0
      0.00user 0.00system 0:01.00elapsed 0%CPU (0avgtext+0avgdata 1988maxresident)k
      0inputs+0outputs (0major+76minor)pagefaults 0swaps
      #
    
    Disable it:
    
      # trace -e clone,*sleep time sleep 1
         0.000 clone(clone_flags: CHILD_CLEARTID|CHILD_SETTID|0x11, newsp: 0, child_tidptr: 0x7ff41e100810) = 21414 (time)
      0.00user 0.00system 0:01.00elapsed 0%CPU (0avgtext+0avgdata 1964maxresident)k
      0inputs+0outputs (0major+76minor)pagefaults 0swaps
      #
    
    Notice that since there is just one thread, the "comm/TID" column is
    suppressed.
    
    Cc: Adrian Hunter <adrian.hunter@intel.com>
    Cc: Jiri Olsa <jolsa@kernel.org>
    Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
    Cc: Namhyung Kim <namhyung@kernel.org>
    Cc: Wang Nan <wangnan0@huawei.com>
    Link: https://lkml.kernel.org/n/tip-thd8s16pagyza71ufi5vjlan@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    d32de87e
builtin-trace.c 107 KB