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From: Sumit Saxena <sumit.saxena@broadcom.com>
Date: Thu, 14 Apr 2022 06:36:01 -0400
Subject: [PATCH] scsi: core: Increase max device queue_depth to 4096
Git-commit: f9bdac31cf4b8609c1b241749b0ceb8f67c8685b
Patch-mainline: v5.19-rc1
References: jsc#PED-1559

The maximum SCSI device queue depth of 1024 is not sufficient for RAID
volumes configured behind Broadcom RAID controllers.  For a 16-drive RAID
volume with a device queue depth limit of 1024, only 64 I/Os (1024/16) can
be issued per drive. That is not sufficient to saturate the device.

Link: https://lore.kernel.org/r/20220414103601.140687-1-sumit.saxena@broadcom.com
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Sumanesh Samanta <sumanesh.samanta@broadcom.com>
Signed-off-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 drivers/scsi/scsi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 211aace69c22..735b6c862b46 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -200,11 +200,11 @@ void scsi_finish_command(struct scsi_cmnd *cmd)
 
 
 /*
- * 1024 is big enough for saturating fast SCSI LUNs.
+ * 4096 is big enough for saturating fast SCSI LUNs.
  */
 int scsi_device_max_queue_depth(struct scsi_device *sdev)
 {
-	return min_t(int, sdev->host->can_queue, 1024);
+	return min_t(int, sdev->host->can_queue, 4096);
 }
 
 /**
-- 
2.35.3