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Date:   Mon, 3 Apr 2023 01:21:38 -0400
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Reply-To: dgilbert@interlog.com
Subject: Re: [PATCH v3 09/11] scsi: scsi_debug: Use scsi_host_busy() in
 delay_store() and ndelay_store()
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To:     John Garry <john.g.garry@oracle.com>, jejb@linux.ibm.com,
        martin.petersen@oracle.com
Cc:     linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        bvanassche@acm.org
References: <20230327074310.1862889-1-john.g.garry@oracle.com>
 <20230327074310.1862889-10-john.g.garry@oracle.com>
From:   Douglas Gilbert <dgilbert@interlog.com>
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On 2023-03-27 03:43, John Garry wrote:
> The functions to update ndelay and delay value first check whether we have
> any in-flight IO for any host. It does this by checking if any tag is used
> in the global submit queues.
> 
> We can achieve the same by setting the host as blocked and then ensuring
> that we have no in-flight commands with scsi_host_busy().
> 
> Note that scsi_host_busy() checks SCMD_STATE_INFLIGHT flag, which is only
> set per command after we ensure that the host is not blocked, i.e. we
> see more commands active after the check for scsi_host_busy() returns 0.
> 
> Signed-off-by: John Garry <john.g.garry@oracle.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>

Thanks.