sync: dump sync state to console on timeout

Change-Id: I74bca6b4a2afa7ed5b1f5233c5165d2edddf269a
Signed-off-by: Erik Gilling <konkers@android.com>

diff --git a/drivers/base/sync.c b/drivers/base/sync.c
index 7fcc0092ac4e72908154ee5f30a5c74e08318a56..4e63d41d6ffdbe934aed88ae283b373a33126481 100644 (file)
--- a/drivers/base/sync.c
+++ b/drivers/base/sync.c
@@ -31,6 +31,7 @@
 static void sync_fence_signal_pt(struct sync_pt *pt);
 static int _sync_pt_has_signaled(struct sync_pt *pt);
 static void sync_fence_free(struct kref *kref);
+static void sync_dump(void);
 
 static LIST_HEAD(sync_timeline_list_head);
 static DEFINE_SPINLOCK(sync_timeline_list_lock);
@@ -573,8 +574,10 @@ int sync_fence_wait(struct sync_fence *fence, long timeout)
        if (fence->status < 0)
                return fence->status;
 
-       if (fence->status == 0)
+       if (fence->status == 0) {
+               sync_dump();
                return -ETIME;
+       }
 
        return 0;
 }
@@ -914,7 +917,34 @@ static __init int sync_debugfs_init(void)
        debugfs_create_file("sync", S_IRUGO, NULL, NULL, &sync_debugfs_fops);
        return 0;
 }
-
 late_initcall(sync_debugfs_init);
 
+#define DUMP_CHUNK 256
+static char sync_dump_buf[64 * 1024];
+void sync_dump(void)
+{
+       struct seq_file s = {
+               .buf = sync_dump_buf,
+               .size = sizeof(sync_dump_buf) - 1,
+       };
+       int i;
+
+       sync_debugfs_show(&s, NULL);
+
+       for (i = 0; i < s.count; i += DUMP_CHUNK) {
+               if ((s.count - i) > DUMP_CHUNK) {
+                       char c = s.buf[i + DUMP_CHUNK];
+                       s.buf[i + DUMP_CHUNK] = 0;
+                       pr_cont("%s", s.buf + i);
+                       s.buf[i + DUMP_CHUNK] = c;
+               } else {
+                       s.buf[s.count] = 0;
+                       pr_cont("%s", s.buf + i);
+               }
+       }
+}
+#else
+static void sync_dump(void)
+{
+}
 #endif