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Date: Tue, 21 May 2024 15:52:55 +0530
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Subject: Re: [PATCH v3 1/1] nvme: multipath: Implemented new iopolicy
 "queue-depth"
To: Sagi Grimberg <sagi@grimberg.me>, John Meneghini <jmeneghi@redhat.com>,
        kbusch@kernel.org, hch@lst.de, emilne@redhat.com
Cc: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
        jrani@purestorage.com, randyj@purestorage.com, hare@kernel.org
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From: Nilay Shroff <nilay@linux.ibm.com>
In-Reply-To: <073ae18a-a80e-4a95-a093-36210a3bb230@grimberg.me>
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On 5/21/24 15:45, Sagi Grimberg wrote:
> 
> 
> On 21/05/2024 13:11, Sagi Grimberg wrote:
>>
>>>> Don't think this matters because cancellation only happens when we
>>>> teardown the controller anyways...
>>>>
>>> I think in case if we reset the nvme controller then we don't teardown
>>> controller, isn't it? In this case we cancel all pending requests, and
>>> later restart the controller.
>>
>> Exactly, nvme_mpath_init_ctrl resets the counter.
> 
> Except you're right, the counter reset needs to move to nvme_mpath_init_identify()
> or some place that is called on every controller reset.
Yeah that was my point. Unfortunately, nvme_mpath_init_ctrl() is not called when we do nvme 
controller reset. So either we move nvme_mpath_init_ctrl() to some common place which 
is called from regular controller init code as well as controller reset code path 
or we may explicitly reset nr_active counter from nvme_timeout().

Thanks,
--Nilay