[PATCH 23/30] staging: sync: Update new fence status with sync_fence_signal_pt

From: John Stultz
Date: Thu Feb 28 2013 - 19:44:24 EST


From: Erik Gilling <konkers@xxxxxxxxxxx>

If a fence's pt is signaled before sync_fence_create is called, the fence
will never transition into the signaled state. This also address a tiny
race if a merged fence's pt after sync_fence_get_status checks it's status
and before fence->status is updated.

Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxx>
Cc: Erik Gilling <konkers@xxxxxxxxxxx>
Cc: Daniel Vetter <daniel.vetter@xxxxxxxx>
Cc: Rob Clark <robclark@xxxxxxxxx>
Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
Cc: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: Android Kernel Team <kernel-team@xxxxxxxxxxx>
Signed-off-by: Erik Gilling <konkers@xxxxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
drivers/staging/android/sync.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c
index 2394189..889ca6e 100644
--- a/drivers/staging/android/sync.c
+++ b/drivers/staging/android/sync.c
@@ -295,6 +295,12 @@ struct sync_fence *sync_fence_create(const char *name, struct sync_pt *pt)
list_add(&pt->pt_list, &fence->pt_list_head);
sync_pt_activate(pt);

+ /*
+ * signal the fence in case pt was activated before
+ * sync_pt_activate(pt) was called
+ */
+ sync_fence_signal_pt(pt);
+
return fence;
}
EXPORT_SYMBOL(sync_fence_create);
@@ -457,7 +463,13 @@ struct sync_fence *sync_fence_merge(const char *name,
if (err < 0)
goto err;

- fence->status = sync_fence_get_status(fence);
+ /*
+ * signal the fence in case one of it's pts were activated before
+ * they were activated
+ */
+ sync_fence_signal_pt(list_first_entry(&fence->pt_list_head,
+ struct sync_pt,
+ pt_list));

return fence;
err:
--
1.7.10.4

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