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Message-ID: <3ed022dd-3026-542a-c3b0-e4f4005208aa@linux.ibm.com>
Date:   Mon, 15 Aug 2022 18:53:45 +0200
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Subject: Re: [PATCH] scsi: increase scsi device's iodone_cnt in scsi_timeout()
Content-Language: en-US
To:     Wenchao Hao <haowenchao22@gmail.com>,
        "James E . J . Bottomley" <jejb@linux.ibm.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     Wenchao Hao <haowenchao@huawei.com>
References: <20220815164324.645550-1-haowenchao@huawei.com>
From:   Steffen Maier <maier@linux.ibm.com>
In-Reply-To: <20220815164324.645550-1-haowenchao@huawei.com>
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On 8/15/22 18:43, Wenchao Hao wrote:
> The iodone_cnt might be less than iorequest_cnt because
> we did not increase the iodone_cnt when a command is done
> from timeout.
> 
> Signed-off-by: Wenchao Hao <haowenchao@huawei.com>
> ---
>   drivers/scsi/scsi_error.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
> index 448748e3fba5..d21ae0090166 100644
> --- a/drivers/scsi/scsi_error.c
> +++ b/drivers/scsi/scsi_error.c
> @@ -355,6 +355,7 @@ enum blk_eh_timer_return scsi_timeout(struct request *req)
>   		 */
>   		if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state))
>   			return BLK_EH_RESET_TIMER;
> +		atomic_inc(&scmd->device->iodone_cnt);
>   		if (scsi_abort_command(scmd) != SUCCESS) {
>   			set_host_byte(scmd, DID_TIME_OUT);
>   			scsi_eh_scmd_add(scmd);

Not sure, but can't we still get a (late) regular completion even after the 
timeout happened (double accounting) and before we successfully aborted the 
command?


-- 
Mit freundlichen Gruessen / Kind regards
Steffen Maier

Linux on IBM Z and LinuxONE

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