ps3: Remove deprecated create_singlethread_workqueue
authorBhaktipriya Shridhar <bhaktipriya96@gmail.com>
Tue, 30 Aug 2016 17:14:51 +0000 (22:44 +0530)
committerMichael Ellerman <mpe@ellerman.id.au>
Mon, 4 Dec 2017 04:01:08 +0000 (15:01 +1100)
commitf0200c02883367f0eb6c9e2f19a8ab6335a52b86
tree1f134b60e94a40451cf3fcbb323b6f6405d3dfec
parent0aa8ff9b76282300d16e0a1403b115996ff88a4c
ps3: Remove deprecated create_singlethread_workqueue

The workqueue "ps3av->wq" queues a single work item &ps3av->work and hence
doesn't require ordering. It is involved in waking up ps3avd to do the
video mode setting and hence it's not being used on a memory reclaim
path. Hence, it has been converted to use system_wq.

System workqueues have been able to handle high level of concurrency
for a long time now and hence it's not required to have a singlethreaded
workqueue just to gain concurrency. Unlike a dedicated per-cpu workqueue
created with create_singlethread_workqueue(), system_wq allows multiple
work items to overlap executions even on the same CPU; however, a
per-cpu workqueue doesn't have any CPU locality or global ordering
guarantee unless the target CPU is explicitly specified and thus the
increase of local concurrency shouldn't make any difference.

The work item has been flushed in ps3av_remove to ensure that
there are no pending tasks while disconnecting the driver.

Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
drivers/ps3/ps3av.c