scsi: ufs: Remove the SCSI timeout handler

This change “scsi: ufs: Remove the SCSI timeout handler” (commit 0dd0dec) in Linux kernel is authored by Bart Van Assche <bvanassche [at] acm.org> on Tue Dec 24 14:02:48 2019 -0800.

Description of "scsi: ufs: Remove the SCSI timeout handler"

The change “scsi: ufs: Remove the SCSI timeout handler” introduces changes as follows.

scsi: ufs: Remove the SCSI timeout handler

The UFS SCSI timeout handler was needed to compensate that
ufshcd_queuecommand() could return SCSI_MLQUEUE_HOST_BUSY for a long
time. Commit a276c19e3e98 ("scsi: ufs: Avoid busy-waiting by eliminating
tag conflicts") fixed this so the timeout handler is no longer necessary.

See also commit f550c65b543b ("scsi: ufs: implement scsi host timeout handler").

Cc: Bean Huo <beanhuo@micron.com>
Cc: Can Guo <cang@codeaurora.org>
Cc: Avri Altman <avri.altman@wdc.com>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20191224220248.30138-7-bvanassche@acm.org
Reviewed-by: Can Guo <cang@codeaurora.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Linux kernel releases containing commit 0dd0dec

The Linux kernel releases containing this commit are as follows.

Linux kernel code changes from "scsi: ufs: Remove the SCSI timeout handler"

There are 36 lines of Linux source code added/deleted in this change. Code changes to Linux kernel are as follows.

 drivers/scsi/ufs/ufshcd.c | 36 ------------------------------------
 1 file changed, 36 deletions(-)
 
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index f8e5f2d9af17..b01c58ff8e8f 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -7068,41 +7068,6 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
 	ufshcd_probe_hba(hba);
 }
 
-static enum blk_eh_timer_return ufshcd_eh_timed_out(struct scsi_cmnd *scmd)
-{
-	unsigned long flags;
-	struct Scsi_Host *host;
-	struct ufs_hba *hba;
-	int index;
-	bool found = false;
-
-	if (!scmd || !scmd->device || !scmd->device->host)
-		return BLK_EH_DONE;
-
-	host = scmd->device->host;
-	hba = shost_priv(host);
-	if (!hba)
-		return BLK_EH_DONE;
-
-	spin_lock_irqsave(host->host_lock, flags);
-
-	for_each_set_bit(index, &hba->outstanding_reqs, hba->nutrs) {
-		if (hba->lrb[index].cmd == scmd) {
-			found = true;
-			break;
-		}
-	}
-
-	spin_unlock_irqrestore(host->host_lock, flags);
-
-	/*
-	 * Bypass SCSI error handling and reset the block layer timer if this
-	 * SCSI command was not actually dispatched to UFS driver, otherwise
-	 * let SCSI layer handle the error as usual.
-	 */
-	return found ? BLK_EH_DONE : BLK_EH_RESET_TIMER;
-}
-
 static const struct attribute_group *ufshcd_driver_groups[] = {
 	&ufs_sysfs_unit_descriptor_group,
 	&ufs_sysfs_lun_attributes_group,
@@ -7121,7 +7086,6 @@ static struct scsi_host_template ufshcd_driver_template = {
 	.eh_abort_handler	= ufshcd_abort,
 	.eh_device_reset_handler = ufshcd_eh_device_reset_handler,
 	.eh_host_reset_handler   = ufshcd_eh_host_reset_handler,
-	.eh_timed_out		= ufshcd_eh_timed_out,
 	.this_id		= -1,
 	.sg_tablesize		= SG_ALL,
 	.cmd_per_lun		= UFSHCD_CMD_PER_LUN,

The commit for this change in Linux stable tree is 0dd0dec (patch).

Last modified: 2020/02/08