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Message-ID: <d9319087-1e97-4a55-aaed-dbce8fe3b0f7@redhat.com>
Date: Thu, 8 Feb 2024 14:33:50 -0500
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Subject: Re: [PATCH wq/for-6.9 v5 0/4] workqueue: Enable unbound cpumask
 update on ordered workqueues
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To: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>, linux-kernel@vger.kernel.org,
 Juri Lelli <juri.lelli@redhat.com>, Cestmir Kalina <ckalina@redhat.com>,
 Alex Gladkov <agladkov@redhat.com>, Phil Auld <pauld@redhat.com>,
 Costa Shulyupin <cshulyup@redhat.com>
References: <20240208161014.1084943-1-longman@redhat.com>
 <ZcUq3VnputFml3LK@slm.duckdns.org>
From: Waiman Long <longman@redhat.com>
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On 2/8/24 14:26, Tejun Heo wrote:
> On Thu, Feb 08, 2024 at 11:10:10AM -0500, Waiman Long wrote:
>>   v5:
>>    - [v4] https://lore.kernel.org/lkml/20240207011911.975608-1-longman@redhat.com/
>>    - Streamline patch 2 by simplifying unplug_oldest_pwq() and calling it
>>      only in pwq_release_workfn().
>>
>>   v4:
>>    - [v3] https://lore.kernel.org/lkml/20240205194602.871505-1-longman@redhat.com/
>>    - Rebase on the latest for-6.9 branch again & discard the use of
>>      __WQ_ORDERED_EXPLICIT and resetting of __WQ_ORDERED.
>>    - Add a new patch 1 to change the ordering of pwq's in wq->pwqs from
>>      oldest to newest.
>>    - Change the terminalogy from freeze/thaw to plug/unplug.
>>    - Allow more than 2 pwq's in wq->pwqs of ordered workqueue but only the
>>      oldest one is unplugged. This eliminates the need to wait for
>>      the draining of extra pwq in workqueue_apply_unbound_cpumask().
>>
>>   v3:
>>    - [v2] https://lore.kernel.org/lkml/20240203154334.791910-1-longman@redhat.com/
>>    - Drop patch 1 as it has been merged into the for-6.9 branch.
>>    - Use rcu_access_pointer() to access wq->dfl_pwq.
>>    - Use RCU protection instead of acquiring wq->mutex in
>>      apply_wqattrs_cleanup().
> Applied the series w/ (w/ the updated second patch) to wq/for-6.9.
>
> Thanks for working on this. It's really great that this got solved finally.

Me too. Thanks for all the good suggestions that you had given me as I 
don't have a full understanding of all the different pieces of the 
workqueue code.

Cheers,
Longman