linux/tools
Greg Price b21484f1a1 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>
2013-07-12 13:53:55 -03:00
..
cgroup cgroups: fix cgroup_event_listener error handling 2013-01-08 10:00:44 -08:00
firewire tools/firewire: nosy-dump: check for allocation failure 2012-12-02 20:10:18 +01:00
hv tools: hv: Improve error logging in KVP daemon. 2013-06-17 15:54:59 -07:00
include/tools tools/include: Add byteshift headers for endian access 2012-02-28 10:22:51 -08:00
lguest lguest: fix paths in comments 2013-03-07 09:56:46 +11:00
lib tools lib traceevent: Port kbuffer parser routines 2013-07-12 13:52:16 -03:00
net filter: add minimal BPF JIT image disassembler 2013-03-21 11:35:41 -04:00
nfsd NFSD: Added fault injection script 2011-11-07 21:10:47 -05:00
perf perf report/top: Add option to collapse undesired parts of call graph 2013-07-12 13:53:55 -03:00
power turbostat: Increase output buffer size to accommodate C8-C10 2013-06-13 09:55:56 -07:00
scripts tools: Get only verbose output with V=1 2013-07-08 17:31:34 -03:00
testing revert "selftest: add simple test for soft-dirty bit" 2013-05-24 16:22:52 -07:00
usb tools: usb: ffs-test: Fix build failure 2013-03-07 12:23:17 +08:00
virtio tools/virtio: remove virtqueue_add_buf() from tests. 2013-03-20 15:45:07 +10:30
vm tools/vm: Switch to liblk library 2013-03-15 13:06:01 -03:00
Makefile Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-05-01 14:08:52 -07:00