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Date: Mon, 5 Feb 2024 10:48:28 +0100
From: Juri Lelli <juri.lelli@redhat.com>
To: Waiman Long <longman@redhat.com>
Cc: Tejun Heo <tj@kernel.org>, Lai Jiangshan <jiangshanlai@gmail.com>,
	linux-kernel@vger.kernel.org, Cestmir Kalina <ckalina@redhat.com>,
	Alex Gladkov <agladkov@redhat.com>, Phil Auld <pauld@redhat.com>,
	Costa Shulyupin <cshulyup@redhat.com>
Subject: Re: [PATCH-wq v2 0/5] workqueue: Enable unbound cpumask update on
 ordered workqueues
Message-ID: <ZcCu7GWMPWOFYAFY@localhost.localdomain>
References: <20240203154334.791910-1-longman@redhat.com>
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In-Reply-To: <20240203154334.791910-1-longman@redhat.com>

Hi,

On 03/02/24 10:43, Waiman Long wrote:
>  v2:
>   - [v1] https://lore.kernel.org/all/20240130183336.511948-1-longman@redhat.com/
>   - Rebased on top of wq's for-v6.9 branch.
>   - Use the new pwq_tryinc_nr_active() mechanism to freeze the new
>     pwq of an ordered workqueue until the old pwq has been properly
>     drained to maintain ordering.
>   - Make rescuer follow changes in workqueue unbound cpumask as well
>     as its sysfs cpumask, if available.
> 
> Ordered workqueues does not currently follow changes made to the
> global unbound cpumask because per-pool workqueue changes may break
> the ordering guarantee. IOW, a work function in an ordered workqueue
> may run on a cpuset isolated CPU.
> 
> This series enables ordered workqueues to follow changes made to
> the global unbound cpumask by temporaily freeze the newly allocated
> pool_workqueue by using the new frozen flag to freeze execution of
> newly queued work items until the old pwq has been properly flushed.
> 
> The cpumask of the rescuer task of each workqueue is also made to follow
> changes in workqueue unbound cpumask as well as its sysfs cpumask,
> if available.

From a testing point of view this now looks good to me.

Tested-by: Juri Lelli <juri.lelli@redhat.com>

Best,
Juri