Date:   Mon, 27 Feb 2023 15:15:51 -0800
From:   Jaegeuk Kim <jaegeuk@kernel.org>
To:     Christoph Hellwig <hch@infradead.org>
Cc:     linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        Bart Van Assche <bvanassche@acm.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Avri Altman <avri.altman@wdc.com>,
        Bean Huo <beanhuo@micron.com>,
        Stanley Chu <stanley.chu@mediatek.com>,
        Can Guo <cang@codeaurora.org>
Subject: Re: [PATCH] scsi: ufs: support IO traces for zoned block device
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References: <20230215190448.1687786-1-jaegeuk@kernel.org>
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On 02/15, Christoph Hellwig wrote:
> Why does UFS even have it's own common tracing instad of just relying
> on the core SCSI one, and even worse pokes into command set specifics
> which is a no-go for LLDDs.  This code simply needs to go away instead
> of beeing "enhanced".

I'm not sure how all the other vendors use the trace tho, at least to me,
it's quite useful when debugging any UFS-specific information such as
group_id and doorbell status along with the attached scsi command, in
addition to the accurate latency measurements.