• Gustavo Padovan's avatar
    dma-buf/fence: add fence_array fences v6 · b3dfbdf2
    Gustavo Padovan authored
    struct fence_array inherits from struct fence and carries a
    collection of fences that needs to be waited together.
    It is useful to translate a sync_file to a fence to remove the complexity
    of dealing with sync_files on DRM drivers. So even if there are many
    fences in the sync_file that needs to waited for a commit to happen,
    they all get added to the fence_collection and passed for DRM use as
    a standard struct fence.
    That means that no changes needed to any driver besides supporting fences.
    To avoid fence_array's fence allocates a new timeline if needed (when
    combining fences from different timelines).
    v2: Comments by Daniel Vetter:
    	- merge fence_collection_init() and fence_collection_add()
    	- only add callbacks at ->enable_signalling()
    	- remove fence_collection_put()
    	- check for type on to_fence_collection()
    	- adjust fence_is_later() and fence_later() to WARN_ON() if they
    	are used with collection fences.
    v3: - Initialize fence_cb.node at fence init.
        Comments by Chris Wilson:
    	- return "unbound" on fence_collection_get_timeline_name()
    	- don't stop adding callbacks if one fails
    	- remove redundant !! on fence_collection_enable_signaling()
    	- remove redundant () on fence_collection_signaled
    	- use fence_default_wait() instead
    v4 (chk): Rework, simplification and cleanup:
    	- Drop FENCE_NO_CONTEXT handling, always allocate a context.
    	- Rename to fence_array.
    	- Return fixed driver name.
    	- Register only one callback at a time.
    	- Document that create function takes ownership of array.
    v5 (chk): More work and fixes:
    	- Avoid deadlocks by adding all callbacks at once again.
    	- Stop trying to remove the callbacks.
    	- Provide context and sequence number for the array fence.
    v6 (chk): Fixes found during testing
    	- Fix stupid typo in _enable_signaling().
    Signed-off-by: default avatarGustavo Padovan <gustavo.padovan@collabora.co.uk>
    Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
    Reviewed-by: default avatarGustavo Padovan <gustavo.padovan@collabora.co.uk>
    Acked-by: default avatarSumit Semwal <sumit.semwal@linaro.org>
    [danvet: Improve commit message as suggested by Gustavo.]
    Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
    Link: http://patchwork.freedesktop.org/patch/msgid/1464786612-5010-3-git-send-email-deathsimple@vodafone.de
Makefile 109 Bytes