diff options
| author | Bhaktipriya Shridhar <bhaktipriya96@gmail.com> | 2016-08-30 23:29:51 +0530 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2016-09-07 19:34:28 +0200 |
| commit | 3706feacd007c89f49bdb20c5c1dd17c8badfc43 (patch) | |
| tree | a719e04c4f1871e8271eb3d2091cef727a3288db | |
| parent | f15a75eedc18e1fece8e01f1a6f7d135e61b0750 (diff) | |
KVM: Remove deprecated create_singlethread_workqueue
The workqueue "irqfd_cleanup_wq" queues a single work item
&irqfd->shutdown and hence doesn't require ordering. It is a host-wide
workqueue for issuing deferred shutdown requests aggregated from all
vm* instances. It is not being used on a memory reclaim path.
Hence, it has been converted to use system_wq.
The work item has been flushed in kvm_irqfd_release().
The workqueue "wqueue" queues a single work item &timer->expired
and hence doesn't require ordering. Also, it is 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.
Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>