perf tools: Add __data_loc support

This patch is required to test the next patch for perf lock.

At 064739bc4b3d7f424b2f25547e6611bcf0132415 ,
support for the modifier "__data_loc" of format is added.

But, when I wanted to parse format of lock_acquired (or some
event else), raw_field_ptr() did not returned correct pointer.

So I modified raw_field_ptr() like this patch. Then
raw_field_ptr() works well.

Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <1264851813-8413-2-git-send-email-mitake@dcl.info.waseda.ac.jp>
[ v3: fixed minor stylistic detail ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 9 insertions, 0 deletions

diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index c5c32be040bf..c4b3cb8a02b1 100644
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -1925,6 +1925,15 @@ void *raw_field_ptr(struct event *event, const char *name, void *data)
         if (!field)
                 return NULL;
 
+        if (field->flags & FIELD_IS_STRING) {
+                int offset;
+
+                offset = *(int *)(data + field->offset);
+                offset &= 0xffff;
+
+                return data + offset;
+        }
+
         return data + field->offset;
 }