• Kyle Meyer's avatar
    perf tools: Increase MAX_NR_CPUS and MAX_CACHES · 9f94c7f9
    Kyle Meyer authored
    Attempting to profile 1024 or more CPUs with perf causes two errors:
    
      perf record -a
      [ perf record: Woken up X times to write data ]
      way too many cpu caches..
      [ perf record: Captured and wrote X MB perf.data (X samples) ]
    
      perf report -C 1024
      Error: failed to set  cpu bitmap
      Requested CPU 1024 too large. Consider raising MAX_NR_CPUS
    
      Increasing MAX_NR_CPUS from 1024 to 2048 and redefining MAX_CACHES as
      MAX_NR_CPUS * 4 returns normal functionality to perf:
    
      perf record -a
      [ perf record: Woken up X times to write data ]
      [ perf record: Captured and wrote X MB perf.data (X samples) ]
    
      perf report -C 1024
      ...
    Signed-off-by: default avatarKyle Meyer <kyle.meyer@hpe.com>
    Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
    Cc: Jiri Olsa <jolsa@redhat.com>
    Cc: Namhyung Kim <namhyung@kernel.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Link: http://lkml.kernel.org/r/20190620193630.154025-1-meyerk@stormcage.eag.rdlabs.hpecorp.netSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    9f94c7f9
perf.h 2.47 KB