• Kan Liang's avatar
    perf callchain: Per-event type selection support · d457c963
    Kan Liang authored
    This patchkit adds the ability to set callgraph mode (fp, dwarf, lbr) per
    event. This in term can reduce sampling overhead and the size of the
    perf.data.
    
    Here is an example.
    
      perf record -e 'cpu/cpu-cycles,period=1000,call-graph=fp,time=1/,cpu/instructions,call-graph=lbr/' sleep 1
    
     perf evlist -v
     cpu/cpu-cycles,period=1000,call-graph=fp,time=1/: type: 4, size: 112,
     config: 0x3c, { sample_period, sample_freq }: 1000, sample_type:
     IP|TID|TIME|CALLCHAIN|PERIOD|IDENTIFIER, read_format: ID, 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
     cpu/instructions,call-graph=lbr/: type: 4, size: 112, config: 0xc0, {
     sample_period, sample_freq }: 4000, sample_type:
     IP|TID|TIME|CALLCHAIN|PERIOD|BRANCH_STACK|IDENTIFIER, read_format: ID,
     disabled: 1, inherit: 1, freq: 1, enable_on_exec: 1, sample_id_all: 1,
     exclude_guest: 1
    Signed-off-by: default avatarKan Liang <kan.liang@intel.com>
    Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    Cc: Andi Kleen <ak@linux.intel.com>
    Cc: Jiri Olsa <jolsa@kernel.org>
    Cc: Namhyung Kim <namhyung@kernel.org>
    Link: http://lkml.kernel.org/r/1439289050-40510-1-git-send-email-kan.liang@intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    d457c963
pmu.c 22.2 KB