The hists__match_hierarchy() is to find matching hist entries in a
group. A matching entry has the same values for all sort keys given.
With an event group (e.g.: -e "{cycles,instructions}"), a leader event
should show other members in a group. So each entry in the leader
should be able to find its pair entries which have same values.
With hierarchy mode, it needs to search all matching children in a
hierarchy.
An example output looks like:
# Overhead Command / Shared Object / Symbol
# ...................... ..................................
#
25.74% 27.18% sh
19.96% 24.14% libc-2.24.so
9.55% 14.64% [.] __strcmp_sse2
1.54% 0.00% [.] __tfind
1.07% 1.13% [.] _int_malloc
...
In the above example, two overheads are shown - one for the leader and
another for the other group member. They were matched since their
command, dso and symbol have the same values.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20160913074552.13284-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
09034de63e