op 04-03-14 09:14, Daniel Vetter schreef:
On Tue, Mar 04, 2014 at 08:50:38AM +0100, Maarten Lankhorst wrote:
op 03-03-14 22:11, Daniel Vetter schreef:
On Mon, Feb 17, 2014 at 04:57:19PM +0100, Maarten Lankhorst wrote:
Android syncpoints can be mapped to a timeline. This removes the need
to maintain a separate api for synchronization. I've left the android
trace events in place, but the core fence events should already be
sufficient for debugging.

- Call fence_remove_callback in sync_fence_free if not all fences have fired.
- Merge Colin Cross' bugfixes, and the android fence merge optimization.
- Merge with the upstream fixes.

Signed-off-by: Maarten Lankhorst <maarten.lankho...@canonical.com>
Snipped everything but headers - Ian Lister from our android team is
signed up to have a more in-depth look at proper integration with android
syncpoints. Adding him to cc.

diff --git a/drivers/staging/android/sync.h b/drivers/staging/android/sync.h
index 62e2255b1c1e..6036dbdc8e6f 100644
--- a/drivers/staging/android/sync.h
+++ b/drivers/staging/android/sync.h
@@ -21,6 +21,7 @@
  #include <linux/list.h>
  #include <linux/spinlock.h>
  #include <linux/wait.h>
+#include <linux/fence.h>

  struct sync_timeline;
  struct sync_pt;
@@ -40,8 +41,6 @@ struct sync_fence;
   * -1 if a will signal before b
   * @free_pt: called before sync_pt is freed
   * @release_obj: called before sync_timeline is freed
- * @print_obj: deprecated
- * @print_pt: deprecated
   * @fill_driver_data: write implementation specific driver data to data.
   *  should return an error if there is not enough room
   *  as specified by size.  This information is returned
@@ -67,13 +66,6 @@ struct sync_timeline_ops {
   /* optional */
   void (*release_obj)(struct sync_timeline *sync_timeline);

- /* deprecated */
- void (*print_obj)(struct seq_file *s,
-  struct sync_timeline *sync_timeline);
- /* deprecated */
- void (*print_pt)(struct seq_file *s, struct sync_pt *sync_pt);
   /* optional */
   int (*fill_driver_data)(struct sync_pt *syncpt, void *data, int size);

@@ -104,42 +96,48 @@ struct sync_timeline {

   /* protected by child_list_lock */
   bool destroyed;
+ int context, value;

   struct list_head child_list_head;
   spinlock_t child_list_lock;

   struct list_head active_list_head;
- spinlock_t active_list_lock;

   struct list_head sync_timeline_list;

   * struct sync_pt - sync point
- * @parent: sync_timeline to which this sync_pt belongs
+ * @fence: base fence class
   * @child_list: membership in sync_timeline.child_list_head
   * @active_list: membership in sync_timeline.active_list_head
+<<<<<<< current
   * @signaled_list: membership in temporary signaled_list on stack
   * @fence: sync_fence to which the sync_pt belongs
   * @pt_list: membership in sync_fence.pt_list_head
   * @status: 1: signaled, 0:active, <0: error
   * @timestamp: time which sync_pt status transitioned from active to
   *  signaled or error.
+>>>>>>> patched
Conflict markers ...
  struct sync_pt {
- struct sync_timeline *parent;
- struct list_head child_list;
+ struct fence base;
Hm, embedding feels wrong, since that still means that I'll need to
implement two kinds of fences in i915 - one using the seqno fence to make
dma-buf sync work, and one to implmenent sync_pt to make the android folks

If I can dream I think we should have a pointer to an underlying fence
here, i.e. a struct sync_pt would just be a userspace interface wrapper to
do explicit syncing using native fences, instead of implicit syncing like
with dma-bufs. But this is all drive-by comments from a very cursory
high-level look. I might be full of myself again ;-)

No, the idea is that because android syncpoint is simply another type of
dma-fence, that if you deal with normal fences then android can
automatically be handled too. The userspace fence api android exposes
could be very easily made to work for dma-fence, just pass a dma-fence
to sync_fence_create.
So exposing dma-fence would probably work for android too.
Hm, then why do we still have struct sync_pt around? Since it's just the
internal bit, with the userspace facing object being struct sync_fence,
I'd opt to shuffle any useful features into the core struct fence.
To keep compatibility with the android api. I think that gradually converting 
them is going to be
more useful than to force all drivers to use a new api all at once. They could 
keep android
syncpoint api for exporting, as long as they accept dma-fence for 

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