From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Date: Mon, 29 Dec 2008 19:27:30 +0000 (+0100)
Subject: ide: ide_hwgroup_t.rq doesn't need an ide_lock held
X-Git-Tag: v2.6.29-rc1~561^2~26
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=1d0bf587df5b17bb93b32d760171417883ca907f;p=linux-2.6-omap-h63xx.git

ide: ide_hwgroup_t.rq doesn't need an ide_lock held

While at it:
- no need to check for hwgroup presence in ide_dump_opcode()

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
---

diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c
index 42ab6d8715f..31f398577ed 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -317,7 +317,8 @@ static void ide_dump_status_no_sense(ide_drive_t *drive, const char *msg, u8 st)
 static int cdrom_decode_status(ide_drive_t *drive, int good_stat, int *stat_ret)
 {
 	ide_hwif_t *hwif = drive->hwif;
-	struct request *rq = hwif->hwgroup->rq;
+	ide_hwgroup_t *hwgroup = hwif->hwgroup;
+	struct request *rq = hwgroup->rq;
 	int stat, err, sense_key;
 
 	/* check for errors */
@@ -508,9 +509,10 @@ end_request:
 
 		spin_lock_irqsave(&ide_lock, flags);
 		blkdev_dequeue_request(rq);
-		HWGROUP(drive)->rq = NULL;
 		spin_unlock_irqrestore(&ide_lock, flags);
 
+		hwgroup->rq = NULL;
+
 		cdrom_queue_request_sense(drive, rq->sense, rq);
 	} else
 		cdrom_end_request(drive, 0);
@@ -950,7 +952,8 @@ static int cdrom_newpc_intr_dummy_cb(struct request *rq)
 static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
 {
 	ide_hwif_t *hwif = drive->hwif;
-	struct request *rq = HWGROUP(drive)->rq;
+	ide_hwgroup_t *hwgroup = hwif->hwgroup;
+	struct request *rq = hwgroup->rq;
 	xfer_func_t *xferfunc;
 	ide_expiry_t *expiry = NULL;
 	int dma_error = 0, dma, stat, thislen, uptodate = 0;
@@ -1157,8 +1160,9 @@ end_request:
 		spin_lock_irqsave(&ide_lock, flags);
 		if (__blk_end_request(rq, 0, dlen))
 			BUG();
-		HWGROUP(drive)->rq = NULL;
 		spin_unlock_irqrestore(&ide_lock, flags);
+
+		hwgroup->rq = NULL;
 	} else {
 		if (!uptodate)
 			rq->cmd_flags |= REQ_FAILED;
diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
index 35b62588280..8afe7b15dec 100644
--- a/drivers/ide/ide-io.c
+++ b/drivers/ide/ide-io.c
@@ -107,17 +107,10 @@ static int __ide_end_request(ide_drive_t *drive, struct request *rq,
 int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
 {
 	unsigned int nr_bytes = nr_sectors << 9;
-	struct request *rq;
+	struct request *rq = drive->hwif->hwgroup->rq;
 	unsigned long flags;
 	int ret = 1;
 
-	/*
-	 * room for locking improvements here, the calls below don't
-	 * need the queue lock held at all
-	 */
-	spin_lock_irqsave(&ide_lock, flags);
-	rq = HWGROUP(drive)->rq;
-
 	if (!nr_bytes) {
 		if (blk_pc_request(rq))
 			nr_bytes = rq->data_len;
@@ -125,9 +118,10 @@ int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
 			nr_bytes = rq->hard_cur_sectors << 9;
 	}
 
+	spin_lock_irqsave(&ide_lock, flags);
 	ret = __ide_end_request(drive, rq, uptodate, nr_bytes, 1);
-
 	spin_unlock_irqrestore(&ide_lock, flags);
+
 	return ret;
 }
 EXPORT_SYMBOL(ide_end_request);
@@ -245,8 +239,9 @@ int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq,
 	unsigned long flags;
 	int ret;
 
-	spin_lock_irqsave(&ide_lock, flags);
 	BUG_ON(!blk_rq_started(rq));
+
+	spin_lock_irqsave(&ide_lock, flags);
 	ret = __ide_end_request(drive, rq, uptodate, nr_sectors << 9, 0);
 	spin_unlock_irqrestore(&ide_lock, flags);
 
@@ -278,7 +273,11 @@ static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq)
 		drive->dev_flags &= ~IDE_DFLAG_BLOCKED;
 		blk_start_queue(drive->queue);
 	}
-	HWGROUP(drive)->rq = NULL;
+	spin_unlock_irqrestore(&ide_lock, flags);
+
+	drive->hwif->hwgroup->rq = NULL;
+
+	spin_lock_irqsave(&ide_lock, flags);
 	if (__blk_end_request(rq, 0, 0))
 		BUG();
 	spin_unlock_irqrestore(&ide_lock, flags);
@@ -300,12 +299,9 @@ static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq)
  
 void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
 {
+	ide_hwgroup_t *hwgroup = drive->hwif->hwgroup;
+	struct request *rq = hwgroup->rq;
 	unsigned long flags;
-	struct request *rq;
-
-	spin_lock_irqsave(&ide_lock, flags);
-	rq = HWGROUP(drive)->rq;
-	spin_unlock_irqrestore(&ide_lock, flags);
 
 	if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
 		ide_task_t *task = (ide_task_t *)rq->special;
@@ -333,15 +329,16 @@ void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
 		return;
 	}
 
-	spin_lock_irqsave(&ide_lock, flags);
-	HWGROUP(drive)->rq = NULL;
+	hwgroup->rq = NULL;
+
 	rq->errors = err;
+
+	spin_lock_irqsave(&ide_lock, flags);
 	if (unlikely(__blk_end_request(rq, (rq->errors ? -EIO : 0),
 				       blk_rq_bytes(rq))))
 		BUG();
 	spin_unlock_irqrestore(&ide_lock, flags);
 }
-
 EXPORT_SYMBOL(ide_end_drive_cmd);
 
 static void ide_kill_rq(ide_drive_t *drive, struct request *rq)
@@ -1489,11 +1486,12 @@ out:
 
 void ide_do_drive_cmd(ide_drive_t *drive, struct request *rq)
 {
+	ide_hwgroup_t *hwgroup = drive->hwif->hwgroup;
 	unsigned long flags;
-	ide_hwgroup_t *hwgroup = HWGROUP(drive);
 
-	spin_lock_irqsave(&ide_lock, flags);
 	hwgroup->rq = NULL;
+
+	spin_lock_irqsave(&ide_lock, flags);
 	__elv_add_request(drive->queue, rq, ELEVATOR_INSERT_FRONT, 0);
 	blk_start_queueing(drive->queue);
 	spin_unlock_irqrestore(&ide_lock, flags);
diff --git a/drivers/ide/ide-lib.c b/drivers/ide/ide-lib.c
index 9fc4cfb2a27..1932119dfa0 100644
--- a/drivers/ide/ide-lib.c
+++ b/drivers/ide/ide-lib.c
@@ -277,14 +277,9 @@ int ide_set_xfer_rate(ide_drive_t *drive, u8 rate)
 
 static void ide_dump_opcode(ide_drive_t *drive)
 {
-	struct request *rq;
+	struct request *rq = drive->hwif->hwgroup->rq;
 	ide_task_t *task = NULL;
 
-	spin_lock(&ide_lock);
-	rq = NULL;
-	if (HWGROUP(drive))
-		rq = HWGROUP(drive)->rq;
-	spin_unlock(&ide_lock);
 	if (!rq)
 		return;