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author | Greg Price <price@MIT.EDU> | 2012-12-06 21:48:05 -0800 |
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committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2013-07-12 13:53:55 -0300 |
commit | b21484f1a1f300d422cfe5d4f8f50015e22cea24 (patch) | |
tree | 145db22403268858a54a07db111464ff24b6818c /tools/perf/builtin-top.c | |
parent | dc098b35b56f83ae088e4291a4e389a6ff126965 (diff) | |
download | lwn-b21484f1a1f300d422cfe5d4f8f50015e22cea24.tar.gz lwn-b21484f1a1f300d422cfe5d4f8f50015e22cea24.zip |
perf report/top: Add option to collapse undesired parts of call graph
For example, in an application with an expensive function implemented
with deeply nested recursive calls, the default call-graph presentation
is dominated by the different callchains within that function. By
ignoring these callees, we can collect the callchains leading into the
function and compactly identify what to blame for expensive calls.
For example, in this report the callers of garbage_collect() are
scattered across the tree:
$ perf report -d ruby 2>- | grep -m10 ^[^#]*[a-z]
22.03% ruby [.] gc_mark
--- gc_mark
|--59.40%-- mark_keyvalue
| st_foreach
| gc_mark_children
| |--99.75%-- rb_gc_mark
| | rb_vm_mark
| | gc_mark_children
| | gc_marks
| | |--99.00%-- garbage_collect
If we ignore the callees of garbage_collect(), its callers are coalesced:
$ perf report --ignore-callees garbage_collect -d ruby 2>- | grep -m10 ^[^#]*[a-z]
72.92% ruby [.] garbage_collect
--- garbage_collect
vm_xmalloc
|--47.08%-- ruby_xmalloc
| st_insert2
| rb_hash_aset
| |--98.45%-- features_index_add
| | rb_provide_feature
| | rb_require_safe
| | vm_call_method
Signed-off-by: Greg Price <price@mit.edu>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20130623031720.GW22203@biohazard-cafe.mit.edu
Link: http://lkml.kernel.org/r/20130708115746.GO22203@biohazard-cafe.mit.edu
Cc: Fengguang Wu <fengguang.wu@intel.com>
[ remove spaces at beginning of line, reported by Fengguang Wu ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/builtin-top.c')
-rw-r--r-- | tools/perf/builtin-top.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index a237059f51cf..bbf463572777 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -773,8 +773,7 @@ static void perf_event__process_sample(struct perf_tool *tool, sample->callchain) { err = machine__resolve_callchain(machine, evsel, al.thread, sample, - &parent); - + &parent, &al); if (err) return; } @@ -1109,6 +1108,9 @@ int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused) OPT_CALLBACK_DEFAULT('G', "call-graph", &top.record_opts, "mode[,dump_size]", record_callchain_help, &parse_callchain_opt, "fp"), + OPT_CALLBACK(0, "ignore-callees", NULL, "regex", + "ignore callees of these functions in call graphs", + report_parse_ignore_callees_opt), OPT_BOOLEAN(0, "show-total-period", &symbol_conf.show_total_period, "Show a column with the sum of periods"), OPT_STRING(0, "dsos", &symbol_conf.dso_list_str, "dso[,dso...]", |