RE: Regarding WQ_MEM_RECLAIM

From: Xue, Zhan
Date: Fri Aug 26 2022 - 03:08:28 EST


Hi Tejun,
The brief point seems the answer to one concern about " workqueue: WQ_MEM_RECLAIM (current wq) is flushing !WQ_MEM_RECLAIM events:(target wq)". If current wq is for memory reclaim , the target wq should be marked with WQ_MEM_RECLAIM as well in case that the flushing target wq (its work items) in the context of current wq is inevitable.


BR
Xuezhan
-----Original Message-----
From: Tejun Heo <htejun@xxxxxxxxx> On Behalf Of tj@xxxxxxxxxx
Sent: Friday, August 26, 2022 2:03 AM
To: Xue, Zhan <zhan.xue@xxxxxxxxx>
Cc: florian@xxxxxxxxxxx; LKML <linux-kernel@xxxxxxxxxxxxxxx>
Subject: Re: Regarding WQ_MEM_RECLAIM

On Wed, Aug 24, 2022 at 06:10:56AM +0000, Xue, Zhan wrote:
> Convert to plain text..

The email's formatting is too painful to reply directly.

Here are two brief points:

* Just don't share the same workqueue between work items which need forward
progress guarantee and ones which don't.

* If something can block memory reclaim, it is in the memory reclaim path by
definition.

Thanks.

--
tejun