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From:   Simon Arlott <simon@octiron.net>
Subject: Re: [PATCH v2] scsi: sr: get rid of sr global mutex
To:     "Merlijn B.W. Wajer" <merlijn@archive.org>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Jens Axboe <jens.axboe@oracle.com>,
        James Bottomley <jejb@linux.ibm.com>
Cc:     linux-scsi@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Christoph Hellwig <hch@infradead.org>
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Date:   Fri, 6 Mar 2020 22:43:02 +0000
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On 24/02/2020 21:20, Merlijn B.W. Wajer wrote:
> Just wanted to check if you planned to apply this v2 (you tried to apply
> v1 but it didn't compile, so I rebased it onto 5.7/scsi-queue as you
> requested). Please let me know if there's anything you'd like to see
> changed.

There's a missing call to mutex_destroy(&cd->lock) in sr_probe() if
there are any failures after calling mutex_init(&cd->lock).

> On 18/02/2020 20:21, Merlijn B.W. Wajer wrote:
>> Perhaps I or someone else can work on removing the usage of the locks,
>> but as it stands I think this addresses the performance issue present in
>> the current kernel, and removing locks and the associated testing
>> required with that is something I am not entirely comfortable doing.

I have a patch to move the locks into the cdrom driver and I've got
multiple PATA drives to test it with.

-- 
Simon Arlott