Commit 3425fbfe authored Apr 08, 2011 by Moger, Babu Committed by James Bottomley May 01, 2011

[SCSI] scsi_dh_rdac : decide whether to send mode select based on operating mode



Based on the operating modes, handler decides whether to send mode
select or not. Purpose here is to reduce io-shipping as much as
possible whenever there is an option.

Signed-off-by: Babu Moger <babu.moger@lsi.com>
Reviewed-by: Yanling Qi <yanling.qi@lsi.com>
Reviewed-by: Sudhir Dachepalli <Sudhir.Dachepalli@lis.com>
Reviewed-by: Somasundaram Krishnasamy <Somasundaram.Krishnasamy@lsi.com>
Reviewed-by: Bob Stankey <Robert.Stankey@lsi.com>
Reviewed-by: Vijay Chauhan <Vijay.Chauhan@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

parent 1c3afc42

drivers/scsi/device_handler/scsi_dh_rdac.c

+16 −1

Original line number	Diff line number	Diff line
		@@ -670,12 +670,27 @@ static int rdac_activate(struct scsi_device *sdev,
		{
		struct rdac_dh_data *h = get_rdac_data(sdev);
		int err = SCSI_DH_OK;
		int act = 0;

		err = check_ownership(sdev, h);
		if (err != SCSI_DH_OK)
		goto done;

		if (h->lun_state == RDAC_LUN_UNOWNED) {
		switch (h->mode) {
		case RDAC_MODE:
		if (h->lun_state == RDAC_LUN_UNOWNED)
		act = 1;
		break;
		case RDAC_MODE_IOSHIP:
		if ((h->lun_state == RDAC_LUN_UNOWNED) &&
		(h->preferred == RDAC_PREFERRED))
		act = 1;
		break;
		default:
		break;
		}

		if (act) {
		err = queue_mode_select(sdev, fn, data);
		if (err == SCSI_DH_OK)
		return 0;