[tip:perf/core] perf unwind: Pass symbol source to libunwind

[tip-bot for Rabin Vincent <tipbot@zytor.com>]

Commit-ID:  7ed4915ad60788d6b846e2cd034f49ee15698143
Gitweb:     http://git.kernel.org/tip/7ed4915ad60788d6b846e2cd034f49ee15698143
Author:     Rabin Vincent <rabin.vincent@axis.com>
AuthorDate: Thu, 29 Oct 2015 08:49:36 +0100
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Thu, 29 Oct 2015 17:48:38 -0300

perf unwind: Pass symbol source to libunwind

Even if --symfs is used to point to the debug binaries, we send in the
non-debug filenames to libunwind, which leads to libunwind not finding
the debug frame.  Fix this by preferring the file in --symfs, if it is
available.

Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rabin Vincent <rabinv@axis.com>
Link: http://lkml.kernel.org/r/1446104978-26429-1-git-send-email-rabin.vincent@axis.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/unwind-libunwind.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
index f729f9e..c83832b 100644
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -360,12 +360,15 @@ find_proc_info(unw_addr_space_t as, unw_word_t ip, unw_proc_info_t *pi,
 		int fd = dso__data_get_fd(map->dso, ui->machine);
 		int is_exec = elf_is_exec(fd, map->dso->name);
 		unw_word_t base = is_exec ? 0 : map->start;
+		const char *symfile;
 
 		if (fd >= 0)
 			dso__data_put_fd(map->dso);
 
+		symfile = map->dso->symsrc_filename ?: map->dso->name;
+
 		memset(&di, 0, sizeof(di));
-		if (dwarf_find_debug_frame(0, &di, ip, base, map->dso->name,
+		if (dwarf_find_debug_frame(0, &di, ip, base, symfile,
 					   map->start, map->end))
 			return dwarf_search_unwind_table(as, ip, &di, pi,
 							 need_unwind_info, arg);