• Namhyung Kim's avatar
    perf lock contention: Fix memory sanitizer issue · 005ef2b4
    Namhyung Kim authored
    
    
    The msan reported a use-of-uninitialized-value warning for the struct
    lock_contention_data in lock_contention_read().  While it'd be filled
    by bpf_map_lookup_elem(), let's just initialize it to silence the
    warning.
    
      ==12524==WARNING: MemorySanitizer: use-of-uninitialized-value
      #0 0x562b0f16b1cd in lock_contention_read  util/bpf_lock_contention.c:139:7
      #1 0x562b0ef65ec6 in __cmd_contention  builtin-lock.c:1737:3
      #2 0x562b0ef65ec6 in cmd_lock  builtin-lock.c:1992:8
      #3 0x562b0ee7f50b in run_builtin  perf.c:322:11
      #4 0x562b0ee7efc1 in handle_internal_command  perf.c:376:8
      #5 0x562b0ee7e1e9 in run_argv  perf.c:420:2
      #6 0x562b0ee7e1e9 in main  perf.c:550:3
      #7 0x7f065f10e632 in __libc_start_main (/usr/lib64/libc.so.6+0x61632)
      #8 0x562b0edf2fa9 in _start (perf+0xfa9)
      SUMMARY: MemorySanitizer: use-of-uninitialized-value (perf+0xe15160) in lock_contention_read
    Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
    Cc: Adrian Hunter <adrian.hunter@intel.com>
    Cc: Ian Rogers <irogers@google.com>
    Cc: Ingo Molnar <mingo@kernel.org>
    Cc: Jiri Olsa <jolsa@kernel.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Link: https://lore.kernel.org/r/20221028180128.3311491-2-namhyung@kernel.org
    
    Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    005ef2b4
bpf_lock_contention.c 4.22 KB