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Date:   Mon, 16 Jan 2023 17:09:58 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Kemeng Shi <shikemeng@huaweicloud.com>
Cc:     Christoph Hellwig <hch@lst.de>, axboe@kernel.dk, dwagner@suse.de,
        hare@suse.de, ming.lei@redhat.com, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, john.garry@huawei.com, jack@suse.cz
Subject: Re: [PATCH v3 07/14] blk-mq: make blk_mq_commit_rqs a general
 function for all commits
Message-ID: <20230116160958.GB23434@lst.de>
References: <20230111130159.3741753-1-shikemeng@huaweicloud.com> <20230111130159.3741753-8-shikemeng@huaweicloud.com> <20230111054520.GA17158@lst.de> <c51cbadb-bfd8-5f26-6bc3-5ad975b5db39@huaweicloud.com> <e2ba1495-e9a8-8dfc-4eee-d9a2984bc0d2@huaweicloud.com>
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On Mon, Jan 16, 2023 at 09:07:00AM +0800, Kemeng Shi wrote:
> >> Why?  I think always having the trace even for the commit case seems
> >> very useful for making the traces useful.
> > I think unplug event more likely means that request going to be sent to driver
> > was plugged and in plug list. And the current code do only trace unplug event
> > when dispatching requests from plug list. If so, would it be better to add
> > a new event to trace commit?
> Hi Christoph, which way do you prefer now? Keep unplug event consistent to
> trace commit of requests from plug list only or trace all commits with
> unplug event. Please let me know and I will consider it in next version.
> Thanks.

To me always having the trace feels more useful, but let's see if Jens
has an opinion on it.