[PATCH 2/2] perf probe: Find compilation directory path for lazy matching

[Naohiro Aota <naota@elisp.net>]

If we use lazy matching, it failed to open a souce file if perf command
is invoked outside of compilation directory:

$ perf probe -a '__schedule;clear_*'
Failed to open kernel/sched/core.c: No such file or directory
  Error: Failed to add events. (-2)

OTOH, other commands like "probe -L" can solve the souce directory by
themselves. Let's make it possible for lazy matching too!

Signed-off-by: Naohiro Aota <naota@elisp.net>
---
 tools/perf/util/probe-finder.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index b5247d7..8e0714c 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -39,6 +39,7 @@
 #include "util.h"
 #include "symbol.h"
 #include "probe-finder.h"
+#include "probe-event.h"
 
 /* Kprobe tracer basic type is up to u64 */
 #define MAX_BASIC_TYPE_BITS	64
@@ -849,11 +850,23 @@ static int probe_point_lazy_walker(const char *fname, int lineno,
 static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
 {
 	int ret = 0;
+	char *fpath;
 
 	if (intlist__empty(pf->lcache)) {
+		const char *comp_dir;
+
+		comp_dir = cu_get_comp_dir(&pf->cu_die);
+		ret = get_real_path(pf->fname, comp_dir, &fpath);
+		if (ret < 0) {
+			free(fpath);
+			pr_warning("Failed to find source file path.\n");
+			return ret;
+		}
+
 		/* Matching lazy line pattern */
-		ret = find_lazy_match_lines(pf->lcache, pf->fname,
+		ret = find_lazy_match_lines(pf->lcache, fpath,
 					    pf->pev->point.lazy_line);
+		free(fpath);
 		if (ret <= 0)
 			return ret;
 	}
-- 
2.3.0