leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

perf tools: Compare dso's also when comparing symbols

Browse Source 
Linus reported that sometimes 'perf report -s symbol' exits without any
message on TUI.  David and Jiri found that it's because it failed to add
a hist entry due to an invalid symbol length.

It turns out that sorting by symbol (address) was broken since it only
compares symbol addresses.  The symbol address is a relative address
within a dso thus just checking its address can result in merging
unrelated symbols together.  Fix it by checking dso before comparing
symbol address.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1381802517-18812-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Namhyung Kim 2013-10-15 11:01:56 +09:00 committed by Arnaldo Carvalho de Melo
parent e369517ce5
commit 09600e0f9e
1 changed files with 10 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
tools/perf/util/sort.c
View File

@ -182,9 +182,19 @@ static int64_t _sort__sym_cmp(struct symbol *sym_l, struct symbol *sym_r)
static int64_t
sort__sym_cmp(struct hist_entry *left, struct hist_entry *right)
{
int64_t ret;
if (!left->ms.sym && !right->ms.sym)
return right->level - left->level;
/*
* comparing symbol address alone is not enough since it's a
* relative address within a dso.
*/
ret = sort__dso_cmp(left, right);
if (ret != 0)
return ret;
return _sort__sym_cmp(left->ms.sym, right->ms.sym);
}