• Bhaktipriya Shridhar's avatar
    [media] pvrusb2: Remove deprecated create_singlethread_workqueue · 29a3006e
    Bhaktipriya Shridhar authored
    The workqueue "workqueue" is involved in polling the pvrusb2 hardware
    (pvr2_hdw).
    
    It has a single work item(&hdw->workpoll) and hence doesn't require
    ordering. Also, it is not being used on a memory reclaim path.
    Hence, the singlethreaded workqueue has been replaced with the use of
    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.
    
    Work item has been flushed in pvr2_hdw_destroy to ensure that there are no
    pending tasks while disconnecting the driver.
    Signed-off-by: default avatarBhaktipriya Shridhar <bhaktipriya96@gmail.com>
    Acked-by: default avatarTejun Heo <tj@kernel.org>
    Signed-off-by: default avatarHans Verkuil <hans.verkuil@cisco.com>
    Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
    29a3006e
pvrusb2-hdw.c 138 KB