[RFC v2 0/3] dma-buf/sync_file: rework fences on struct sync_file

[Gustavo Padovan]

From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx>

Hi all,

This is an attempt to improve fence support on Sync File. The basic idea
is to have only sync_file->fence and store all fences there, either as
normal fences or fence_arrays. That way we can remove some potential
duplication when using fence_array with sync_file: the duplication of the array
of fences and the duplication of fence_add_callback() for all fences.

Now when creating a new sync_file during the merge process sync_file_set_fence()
will set sync_file->fence based on the number of fences for that sync_file. If
there is more than one fence a fence_array is created. One important advantage
approach is that we only add one fence callback now, no matter how many fences
there are in a sync_file - the individual callbacks are added by fence_array.

Please review! Thanks!

	Gustavo

Changes since v1 (Comments from Chris Wilson and Christian KÃnig):
	- Not using fence_ops anymore.
	- fence_is_array() was created to differentiate fence from fence_array
	- fence_array_teardown() is now exported and used under fence_is_array()
	- struct sync_file lost num_fences member

Gustavo Padovan (3):
  dma-buf/fence-array: add fence_is_array()
  dma-buf/fence-array: add fence_array_teardown()
  dma-buf/sync_file: rework fence storage in struct file

 drivers/dma-buf/fence-array.c        |  25 ++++++
 drivers/dma-buf/sync_file.c          | 148 +++++++++++++++++++++++------------
 drivers/staging/android/sync_debug.c |   9 ++-
 include/linux/fence-array.h          |  11 +++
 include/linux/sync_file.h            |  15 ++--
 5 files changed, 147 insertions(+), 61 deletions(-)

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2.5.5