perf tools: Compare dso's also when comparing symbols
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>
diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 32c5637..1f9821d 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -182,9 +182,19 @@
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);
}
