Re: (subset) [PATCHSET wq/for-6.5] workqueue: Ordered workqueue creation cleanup

From: Bjorn Andersson
Date: Thu May 25 2023 - 00:57:56 EST


On Thu, 20 Apr 2023 16:50:24 -1000, Tejun Heo wrote:
> When multiple work items are queued to a workqueue, their execution order
> doesn't match the queueing order. They may get executed in any order and
> simultaneously. When fully serialized execution - one by one in the queueing
> order - is needed, an ordered workqueue should be used which can be created
> with alloc_ordered_workqueue().
>
> However, alloc_ordered_workqueue() was a later addition. Before it, an
> ordered workqueue could be obtained by creating an UNBOUND workqueue with
> @max_active==1. This originally was an implementation side-effect which was
> broken by 4c16bd327c74 ("workqueue: restore WQ_UNBOUND/max_active==1 to be
> ordered"). Because there were users that depended on the ordered execution,
> 5c0338c68706 ("workqueue: restore WQ_UNBOUND/max_active==1 to be ordered")
> made workqueue allocation path to implicitly promote UNBOUND workqueues w/
> @max_active==1 to ordered workqueues.
>
> [...]

Applied, thanks!

[14/22] soc: qcom: qmi: Use alloc_ordered_workqueue() to create ordered workqueues
commit: 56310520308ab863030e9baa9a8f63bb31c94e27

Best regards,
--
Bjorn Andersson <andersson@xxxxxxxxxx>