Subject: Re: [PATCH RFT 0/3] blk-mq: Optimise blk_mq_queue_tag_busy_iter() for
 shared tags
From:   John Garry <john.garry@huawei.com>
To:     Kashyap Desai <kashyap.desai@broadcom.com>, <axboe@kernel.dk>
CC:     <linux-block@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <ming.lei@redhat.com>, <hare@suse.de>
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Date:   Mon, 6 Dec 2021 09:57:39 +0000
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On 26/11/2021 11:51, John Garry wrote:
>> This patch set improves above call trace even after disk_util=0 is set.
> ok, fine. Thanks for testing.
> 
> So I guess that this is a regression, and you would want this series for 
> v5.16, right? My changes were made with v5.17 in mind.
> 
> I am not sure how Jens feels about it, since the changes are 
> significant. It would be a lot easier to argue for v5.16 if we got to 
> this point earlier in the cycle...
> 

note: I will now resend for 5.17 and add your tested-by, please let me 
know if unhappy about that.

> Anyway, it would be good to have full review first, so please help with 
> that.
> 
> @Ming, can you please give feedback on 3/3 here?

Thanks and also to Hannes for the reviews.

john