• Wang Nan's avatar
    perf tools: Enable overwrite settings · 626a6b78
    Wang Nan authored
    This patch allows following config terms and option:
    
    Globally setting events to overwrite;
    
      # perf record --overwrite ...
    
    Set specific events to be overwrite or no-overwrite.
    
      # perf record --event cycles/overwrite/ ...
      # perf record --event cycles/no-overwrite/ ...
    
    Add missing config terms and update the config term array size because
    the longest string length has changed.
    
    For overwritable events, it automatically selects attr.write_backward
    since perf requires it to be backward for reading.
    
    Test result:
    
      # perf record --overwrite -e syscalls:*enter_nanosleep* usleep 1
      [ perf record: Woken up 2 times to write data ]
      [ perf record: Captured and wrote 0.011 MB perf.data (1 samples) ]
      # perf evlist -v
      syscalls:sys_enter_nanosleep: type: 2, size: 112, config: 0x134, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, write_backward: 1
      # Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events
    Signed-off-by: default avatarWang Nan <wangnan0@huawei.com>
    Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
    Cc: Masami Hiramatsu <mhiramat@kernel.org>
    Cc: Namhyung Kim <namhyung@kernel.org>
    Cc: Nilay Vaish <nilayvaish@gmail.com>
    Cc: Zefan Li <lizefan@huawei.com>
    Cc: pi3orama@163.com
    Link: http://lkml.kernel.org/r/1468485287-33422-14-git-send-email-wangnan0@huawei.comSigned-off-by: default avatarHe Kuang <hekuang@huawei.com>
    Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    626a6b78
perf-record.txt 13.8 KB