[tip:perf/core] perf callchain: Fix double mapping al->addr for children without self period

From: tip-bot for Namhyung Kim
Date: Fri Nov 03 2017 - 10:23:18 EST


Commit-ID: d6332a176b869df1839abb26c8f80026a66d21d6
Gitweb: https://git.kernel.org/tip/d6332a176b869df1839abb26c8f80026a66d21d6
Author: Namhyung Kim <namhyung@xxxxxxxxxx>
AuthorDate: Fri, 20 Oct 2017 14:15:33 +0900
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Tue, 31 Oct 2017 16:14:50 -0300

perf callchain: Fix double mapping al->addr for children without self period

Milian Wolff found a problem he described in [1] and that for him would
get fixed:

"Note how most of the large offset values are now gone. Most notably, we
get proper srcline resolution for the random.h and complex headers."

Then Namhyung found the root cause:

"I looked into it and found a bug handling cumulative (children)
entries. For children entries that have no self period, the al->addr (so
he->ip) ends up having an doubly-mapped address.

It seems to be there from the beginning but only affects entries that
have no srclines - finding srcline itself is done using a different
address but it will show the invalid address if no srcline was found. I
think we should fix the commit c7405d85d7a3 ("perf tools: Update cpumode
for each cumulative entry")."

[1] https://lkml.kernel.org/r/20171018185350.14893-7-milian.wolff@xxxxxxxx

Reported-by: Milian Wolff <milian.wolff@xxxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Tested-by: Milian Wolff <milian.wolff@xxxxxxxx>
Cc: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: kernel-team@xxxxxxx
Fixes: c7405d85d7a3 ("perf tools: Update cpumode for each cumulative entry")
Link: https://lkml.kernel.org/r/20171020051533.GA2746@sejong
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/callchain.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 3a39169..8370121 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -1091,10 +1091,7 @@ int fill_callchain_info(struct addr_location *al, struct callchain_cursor_node *
al->map = node->map;
al->sym = node->sym;
al->srcline = node->srcline;
- if (node->map)
- al->addr = node->map->map_ip(node->map, node->ip);
- else
- al->addr = node->ip;
+ al->addr = node->ip;

if (al->sym == NULL) {
if (hide_unresolved)