• Namhyung Kim's avatar
    perf lock: Print the number of lost entries for BPF · 6d499a6b
    Namhyung Kim authored
    Like the normal 'perf lock contention' output, it'd print the number of
    lost entries for BPF if exists or -v option is passed.
    
    Currently it uses BROKEN_CONTENDED stat for the lost count (due to full
    stack maps).
    
      $ sudo perf lock con -a -b --map-nr-entries 128 sleep 5
      ...
      === output for debug===
    
      bad: 43, total: 14903
      bad rate: 0.29 %
      histogram of events caused bad sequence
          acquire: 0
         acquired: 0
        contended: 43
          release: 0
    Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
    Cc: Blake Jones <blakejones@google.com>
    Cc: Boqun Feng <boqun.feng@gmail.com>
    Cc: Davidlohr Bueso <dave@stgolabs.net>
    Cc: Ian Rogers <irogers@google.com>
    Cc: Ingo Molnar <mingo@kernel.org>
    Cc: Jiri Olsa <jolsa@kernel.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Song Liu <songliubraving@fb.com>
    Cc: Waiman Long <longman@redhat.com>
    Cc: Will Deacon <will@kernel.org>
    Link: https://lore.kernel.org/r/20220802191004.347740-3-namhyung@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    6d499a6b
lock_contention.bpf.c 3.59 KB