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Date:   Wed, 24 May 2023 08:15:07 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Bart Van Assche <bvanassche@acm.org>
Cc:     Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
        linux-block@vger.kernel.org, Mike Snitzer <snitzer@kernel.org>,
        Damien Le Moal <dlemoal@kernel.org>,
        Jaegeuk Kim <jaegeuk@kernel.org>
Subject: Re: [PATCH v3 0/7] Submit zoned writes in order
Message-ID: <20230524061507.GF19611@lst.de>
References: <20230522183845.354920-1-bvanassche@acm.org> <20230523072216.GE8758@lst.de> <d372a3b8-f5ef-f281-bb3d-315030504d4f@acm.org>
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On Tue, May 23, 2023 at 01:04:44PM -0700, Bart Van Assche wrote:
>> Can you explain why?  The resulting code looks rather odd to me as we
>> now reach out to a global list from the per-hctx run_queue helper,
>> which seems a bit awkward.
>
> Hi Christoph,
>
> This change is based on the assumption that requeuing and flushing are 
> relatively rare events.

The former are, the latter not so much.  But more importantly you now
look into a global list in the per-hctx dispatch, adding cache line
sharing.

> Do you perhaps want me to change the approach back 
> to one requeue list and one flush list per hctx?

Unless we have a very good reason to make them global that would
be my preference.