[PATCH v3 2/2] scsi: donot increase scsi_device's iorequest_cnt if dispatch failed

[Wenchao Hao]

If scsi_dispatch_cmd() failed, the scsi command did not send to disks,
so it would never done from LLDs.

scsi scsi_queue_rq() would return BLK_STS_RESOURCE if
scsi_dispatch_cmd() failed, the related request would be requeued, and
the timeout of this request would not fired any more, so no one
would increase iodone_cnt which matches with this increase of
iorequest_cnt.

Signed-off-by: Wenchao Hao <haowe...@huawei.com>
Reviewed-by: Mike Christie <michael....@oracle.com>
---
drivers/scsi/scsi_lib.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index ec890865abae..a29d87e57430 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1464,8 +1464,6 @@ static int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
struct Scsi_Host *host = cmd->device->host;
int rtn = 0;

- atomic_inc(&cmd->device->iorequest_cnt);
-
/* check if the device is still usable */
if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
/* in SDEV_DEL we error all commands. DID_NO_CONNECT
@@ -1764,6 +1762,7 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
goto out_dec_host_busy;
}

+ atomic_inc(&cmd->device->iorequest_cnt);
return BLK_STS_OK;

out_dec_host_busy:
--
2.32.0