linux-kernel - Re: [PATCH v2 1/2] blk-mq: In blk_mq_dispatch_rq

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 3 Apr 2020 09:55:16 +0800
From:   Ming Lei <ming.lei@...hat.com>
To:     Douglas Anderson <dianders@...omium.org>
Cc:     axboe@...nel.dk, jejb@...ux.ibm.com, martin.petersen@...cle.com,
        paolo.valente@...aro.org, sqazi@...gle.com,
        linux-block@...r.kernel.org, linux-scsi@...r.kernel.org,
        groeck@...omium.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 1/2] blk-mq: In blk_mq_dispatch_rq_list() "no budget"
 is a reason to kick

On Thu, Apr 02, 2020 at 08:51:29AM -0700, Douglas Anderson wrote:
> In blk_mq_dispatch_rq_list(), if blk_mq_sched_needs_restart() returns
> true and the driver returns BLK_STS_RESOURCE then we'll kick the
> queue.  However, there's another case where we might need to kick it.
> If we were unable to get budget we can be in much the same state as
> when the driver returns BLK_STS_RESOURCE, so we should treat it the
> same.

The situation is really similar, especially the restart handler may
not see the request which may not be added to hctx->dispatch, so

Reviewed-by: Ming Lei <ming.lei@...hat.com>


Thanks, 
Ming