From 9e3961ba2be51a88c6223143568c80e0616d93ce Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Tue, 29 Nov 2005 23:12:59 -0600 Subject: [SCSI] iscsi: lower queue depth From Wang Zhenyu: High queue depth was a problem for some targets so make queue_depth adjustable From Mike Christie Make default queue_depth a little lower Signed-off-by: Mike Christie Signed-off-by: Alex Aizman Signed-off-by: Dmitry Yusupov Signed-off-by: James Bottomley --- drivers/scsi/iscsi_tcp.c | 20 +++++++++++++++----- drivers/scsi/iscsi_tcp.h | 3 ++- 2 files changed, 17 insertions(+), 6 deletions(-) (limited to 'drivers') diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c index 83e2f8c8e496..5b14c404069f 100644 --- a/drivers/scsi/iscsi_tcp.c +++ b/drivers/scsi/iscsi_tcp.c @@ -2401,6 +2401,15 @@ fault: return 0; } +static int +iscsi_change_queue_depth(struct scsi_device *sdev, int depth) +{ + if (depth > ISCSI_MAX_CMD_PER_LUN) + depth = ISCSI_MAX_CMD_PER_LUN; + scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth); + return sdev->queue_depth; +} + static int iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size) { @@ -3260,13 +3269,14 @@ iscsi_r2tpool_free(struct iscsi_session *session) static struct scsi_host_template iscsi_sht = { .name = "iSCSI Initiator over TCP/IP, v." ISCSI_VERSION_STR, - .queuecommand = iscsi_queuecommand, + .queuecommand = iscsi_queuecommand, + .change_queue_depth = iscsi_change_queue_depth, .can_queue = ISCSI_XMIT_CMDS_MAX - 1, .sg_tablesize = ISCSI_SG_TABLESIZE, - .cmd_per_lun = ISCSI_CMD_PER_LUN, - .eh_abort_handler = iscsi_eh_abort, - .eh_host_reset_handler = iscsi_eh_host_reset, - .use_clustering = DISABLE_CLUSTERING, + .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN, + .eh_abort_handler = iscsi_eh_abort, + .eh_host_reset_handler = iscsi_eh_host_reset, + .use_clustering = DISABLE_CLUSTERING, .proc_name = "iscsi_tcp", .this_id = -1, }; diff --git a/drivers/scsi/iscsi_tcp.h b/drivers/scsi/iscsi_tcp.h index d23ae68fae0d..855f2dfd18af 100644 --- a/drivers/scsi/iscsi_tcp.h +++ b/drivers/scsi/iscsi_tcp.h @@ -71,7 +71,8 @@ #define ISCSI_MGMT_CMDS_MAX 32 /* must be power of 2 */ #define ISCSI_MGMT_ITT_OFFSET 0xa00 #define ISCSI_SG_TABLESIZE SG_ALL -#define ISCSI_CMD_PER_LUN 128 +#define ISCSI_DEF_CMD_PER_LUN 32 +#define ISCSI_MAX_CMD_PER_LUN 128 #define ISCSI_TCP_MAX_CMD_LEN 16 #define ITT_MASK (0xfff) -- cgit v1.2.3