[tip:perf/urgent] perf symbols: Fix reading of build-id from vDSO

[tip-bot for Ben Hutchings]

Commit-ID:  40c4a0f92aed570cc529a1e5c24c7e04a0ce8b85
Gitweb:     http://git.kernel.org/tip/40c4a0f92aed570cc529a1e5c24c7e04a0ce8b85
Author:     Ben Hutchings <ben@xxxxxxxxxxxxxxx>
AuthorDate: Wed, 13 Jan 2016 17:23:01 +0000
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Fri, 15 Jan 2016 16:31:58 -0300

perf symbols: Fix reading of build-id from vDSO

We need to use the long name (the filename) when reading the build-id
from a DSO.  Using the short name doesn't work for (at least) vDSOs.

Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20160113172301.GT28542@xxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/symbol.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 3b2de6e..ab02209 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1466,7 +1466,7 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
 	 * Read the build id if possible. This is required for
 	 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
 	 */
-	if (filename__read_build_id(dso->name, build_id, BUILD_ID_SIZE) > 0)
+	if (filename__read_build_id(dso->long_name, build_id, BUILD_ID_SIZE) > 0)
 		dso__set_build_id(dso, build_id);
 
 	/*