linux/drivers/dma-buf
Gustavo Padovan e241655373 dma-buf/sync_file: only enable fence signalling on poll()
Signalling doesn't need to be enabled at sync_file creation, it is only
required if userspace waiting the fence to signal through poll().

Thus we delay fence_add_callback() until poll is called. It only adds the
callback the first time poll() is called. This avoid re-adding the same
callback multiple times.

v2: rebase and update to work with new fence support for sync_file

v3: use atomic operation to set enabled and protect fence_add_callback()

v4: use user bit from fence flags (comment from Chris Wilson)

v5: use ternary if on poll return (comment from Chris Wilson)

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
  [sumits: remove unused var status]
Link: http://patchwork.freedesktop.org/patch/msgid/1470404378-27961-1-git-send-email-gustavo@padovan.org
2016-08-11 15:39:38 +05:30
..
Kconfig dma-buf/sync_file: improve Kconfig description for Sync Files 2016-07-13 19:52:08 +05:30
Makefile dma-buf/fence: add fence_array fences v6 2016-06-02 09:26:15 +02:00
dma-buf.c dma-buf: Release module reference on creation failure 2016-07-18 14:10:49 +02:00
fence-array.c dma-buf/fence-array: add fence_is_array() 2016-08-11 15:33:23 +05:30
fence.c dma-buf/fence: make fence context 64 bit v2 2016-06-02 08:27:41 +02:00
reservation.c reservation: add headerdoc comments 2016-05-31 22:12:43 +05:30
seqno-fence.c dma-buf: Minor coding style fixes 2015-05-21 11:29:59 +05:30
sync_file.c dma-buf/sync_file: only enable fence signalling on poll() 2016-08-11 15:39:38 +05:30