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From: Bart Van Assche <bvanassche-HInyCGIudOg@public.gmane.org>
To: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: dillowda-1Heg1YXhbW8@public.gmane.org,
	roland-BHEL68pLQRGGvPXPguhicg@public.gmane.org
Subject: [PATCH 03/15] ib_srp: Micro-optimize srp_queuecommand()
Date: Sun, 25 Mar 2012 14:50:21 +0000	[thread overview]
Message-ID: <28993193.JhpOJ9jIEO@asus> (raw)
In-Reply-To: <5207288.nSt5MkVMpO@asus>

Block the SCSI host while reconnecting instead of representing
the reconnect activity as a distinct SRP target state.

Signed-off-by: Bart Van Assche <bvanassche-HInyCGIudOg@public.gmane.org>
Cc: David Dillow <dillowda-1Heg1YXhbW8@public.gmane.org>
Cc: Roland Dreier <roland-BHEL68pLQRGGvPXPguhicg@public.gmane.org>
---
 drivers/infiniband/ulp/srp/ib_srp.c |   16 ++++++++--------
 drivers/infiniband/ulp/srp/ib_srp.h |    1 -
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index 6279343..04fbc43 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -610,13 +610,16 @@ static void srp_reset_req(struct srp_target_port *target, struct srp_request *re
 
 static int srp_reconnect_target(struct srp_target_port *target)
 {
+	struct Scsi_Host *shost = target->scsi_host;
 	struct ib_qp_attr qp_attr;
 	struct ib_wc wc;
 	int i, ret;
 
-	if (!srp_change_state(target, SRP_TARGET_LIVE, SRP_TARGET_CONNECTING))
+	if (target->state != SRP_TARGET_LIVE)
 		return -EAGAIN;
 
+	scsi_target_block(&shost->shost_gendev);
+
 	srp_disconnect_target(target);
 	/*
 	 * Now get a new local CM ID so that we avoid confusing the
@@ -654,8 +657,7 @@ static int srp_reconnect_target(struct srp_target_port *target)
 	if (ret)
 		goto err;
 
-	if (!srp_change_state(target, SRP_TARGET_CONNECTING, SRP_TARGET_LIVE))
-		ret = -EAGAIN;
+	scsi_target_unblock(&shost->shost_gendev);
 
 	return ret;
 
@@ -673,13 +675,15 @@ err:
 	 * the flush_scheduled_work() in srp_remove_one().
 	 */
 	spin_lock_irq(&target->lock);
-	if (target->state == SRP_TARGET_CONNECTING) {
+	if (target->state == SRP_TARGET_LIVE) {
 		target->state = SRP_TARGET_DEAD;
 		INIT_WORK(&target->work, srp_remove_work);
 		queue_work(ib_wq, &target->work);
 	}
 	spin_unlock_irq(&target->lock);
 
+	scsi_target_unblock(&shost->shost_gendev);
+
 	return ret;
 }
 
@@ -1268,9 +1272,6 @@ static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
 	unsigned long flags;
 	int len;
 
-	if (target->state == SRP_TARGET_CONNECTING)
-		goto err;
-
 	if (target->state == SRP_TARGET_DEAD ||
 	    target->state == SRP_TARGET_REMOVED) {
 		scmnd->result = DID_BAD_TARGET << 16;
@@ -1334,7 +1335,6 @@ err_iu:
 err_unlock:
 	spin_unlock_irqrestore(&target->lock, flags);
 
-err:
 	return SCSI_MLQUEUE_HOST_BUSY;
 }
 
diff --git a/drivers/infiniband/ulp/srp/ib_srp.h b/drivers/infiniband/ulp/srp/ib_srp.h
index f0daeb3..02dc3ac 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.h
+++ b/drivers/infiniband/ulp/srp/ib_srp.h
@@ -80,7 +80,6 @@ enum {
 
 enum srp_target_state {
 	SRP_TARGET_LIVE,
-	SRP_TARGET_CONNECTING,
 	SRP_TARGET_DEAD,
 	SRP_TARGET_REMOVED
 };
-- 
1.7.7


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  parent reply	other threads:[~2012-03-25 14:50 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-03-25 14:45 [PATCH 00/15, v3] Make ib_srp better suited for H.A. purposes Bart Van Assche
2012-03-25 14:47 ` [PATCH 01/15] ib_srp: Enlarge block layer timeout Bart Van Assche
2012-03-29 16:59   ` Dave Dillow
     [not found]     ` <20120329165931.GA19700-1Heg1YXhbW8@public.gmane.org>
2012-04-22 16:01       ` Bart Van Assche
     [not found]         ` <4F942B74.4040106-HInyCGIudOg@public.gmane.org>
2012-04-30 15:11           ` David Dillow
     [not found]             ` <1335798691.441.2.camel-zHLflQxYYDO4Hhoo1DtQwJ9G+ZOsUmrO@public.gmane.org>
2012-05-19 10:50               ` Bart Van Assche
     [not found]                 ` <4FB77AEE.7030100-HInyCGIudOg@public.gmane.org>
2012-05-30  4:56                   ` David Dillow
2012-03-25 14:48 ` [PATCH 02/15] ib_srp: Introduce srp_handle_qp_err() Bart Van Assche
2012-03-25 14:50 ` Bart Van Assche [this message]
2012-03-25 14:52 ` [PATCH 04/15] ib_srp: Suppress superfluous error messages Bart Van Assche
2012-03-25 14:53 ` [PATCH 05/15] ib_srp: Avoid that SCSI error handling triggers a crash Bart Van Assche
2012-03-25 14:54 ` [PATCH 06/15] ib_srp: Introduce the helper function srp_remove_target() Bart Van Assche
2012-03-25 14:55 ` [PATCH 07/15] ib_srp: Eliminate state SRP_TARGET_DEAD Bart Van Assche
2012-03-25 14:56 ` [PATCH 08/15] ib_srp: Make srp_disconnect_target() wait for IB completions Bart Van Assche
2012-03-25 14:57 ` [PATCH 09/15] srp_transport: Fix atttribute registration Bart Van Assche
2012-03-25 14:58 ` [PATCH 10/15] srp_transport: Simplify attribute initialization code Bart Van Assche
2012-03-25 14:59 ` [PATCH 11/15] srp_transport: Document sysfs attributes Bart Van Assche
2012-03-25 15:00 ` [PATCH 12/15] ib_srp: " Bart Van Assche
2012-03-25 15:01 ` [PATCH 13/15] ib_srp: Allow SRP disconnect through sysfs Bart Van Assche
2012-07-16 22:20   ` Mike Christie
     [not found]     ` <500493B4.4010303-hcNo3dDEHLuVc3sceRu5cw@public.gmane.org>
2012-07-17 12:55       ` bart-LmZ/31Jx5xYUl6sPKNhdgg
2012-03-25 15:02 ` [PATCH 14/15] ib_srp: Introduce a temporary variable in srp_remove_target() Bart Van Assche
2012-03-25 15:03 ` [PATCH 15/15] ib_srp: Maintain a single connection per I_T nexus Bart Van Assche
2012-03-25 15:18 ` [PATCH 00/15, v3] Make ib_srp better suited for H.A. purposes Bart Van Assche
2012-03-27 16:37   ` Dave Dillow

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