diff options
author | Hans Verkuil <hans.verkuil@cisco.com> | 2013-12-13 20:13:38 +0400 |
---|---|---|
committer | Mauro Carvalho Chehab <m.chehab@samsung.com> | 2014-01-07 13:00:04 +0400 |
commit | b18a8ff29d80b132018d33479e86ab8ecaee6b46 (patch) | |
tree | f8bc0cec256e75717d36952b278181f887252041 /include/media/videobuf2-core.h | |
parent | b4fcdaf7654f9506f80d4e3f2b045a78333d62dc (diff) | |
download | linux-b18a8ff29d80b132018d33479e86ab8ecaee6b46.tar.xz |
[media] vb2: push the mmap semaphore down to __buf_prepare()
Rather than taking the mmap semaphore at a relatively high-level function,
push it down to the place where it is really needed.
It was placed in vb2_queue_or_prepare_buf() to prevent racing with other
vb2 calls. The only way I can see that a race can happen is when two
threads queue the same buffer. The solution for that it to introduce
a PREPARING state.
Moving it down offers opportunities to simplify the code.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Diffstat (limited to 'include/media/videobuf2-core.h')
-rw-r--r-- | include/media/videobuf2-core.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index 0ae974ee8894..ea766525a268 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -142,6 +142,7 @@ enum vb2_fileio_flags { /** * enum vb2_buffer_state - current video buffer state * @VB2_BUF_STATE_DEQUEUED: buffer under userspace control + * @VB2_BUF_STATE_PREPARING: buffer is being prepared in videobuf * @VB2_BUF_STATE_PREPARED: buffer prepared in videobuf and by the driver * @VB2_BUF_STATE_QUEUED: buffer queued in videobuf, but not in driver * @VB2_BUF_STATE_ACTIVE: buffer queued in driver and possibly used @@ -154,6 +155,7 @@ enum vb2_fileio_flags { */ enum vb2_buffer_state { VB2_BUF_STATE_DEQUEUED, + VB2_BUF_STATE_PREPARING, VB2_BUF_STATE_PREPARED, VB2_BUF_STATE_QUEUED, VB2_BUF_STATE_ACTIVE, |