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From: "Ed L. Cashin" <ecashin@coraid.com>
To: linux-kernel@vger.kernel.org
Cc: "Ed L. Cashin" <ecashin@coraid.com>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH 05/13] eliminate goto and improve readability
Date: Thu, 20 Dec 2007 17:15:53 -0500	[thread overview]
Message-ID: <1198188961-25147-5-git-send-email-ecashin@coraid.com> (raw)
In-Reply-To: <1198188961-25147-1-git-send-email-ecashin@coraid.com>

Adam Richter suggested eliminating this goto.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoechr.c |   69 +++++++++++++++++++++----------------------
 1 files changed, 34 insertions(+), 35 deletions(-)

diff --git a/drivers/block/aoe/aoechr.c b/drivers/block/aoe/aoechr.c
index 03c7f4a..f112466 100644
--- a/drivers/block/aoe/aoechr.c
+++ b/drivers/block/aoe/aoechr.c
@@ -194,52 +194,51 @@ aoechr_read(struct file *filp, char __user *buf, size_t cnt, loff_t *off)
 	ulong flags;
 
 	n = (unsigned long) filp->private_data;
-	switch (n) {
-	case MINOR_ERR:
-		spin_lock_irqsave(&emsgs_lock, flags);
-loop:
-		em = emsgs + emsgs_head_idx;
-		if ((em->flags & EMFL_VALID) == 0) {
-			if (filp->f_flags & O_NDELAY) {
-				spin_unlock_irqrestore(&emsgs_lock, flags);
-				return -EAGAIN;
-			}
-			nblocked_emsgs_readers++;
+	if (n != MINOR_ERR)
+		return -EFAULT;
+
+	spin_lock_irqsave(&emsgs_lock, flags);
 
+	for (;;) {
+		em = emsgs + emsgs_head_idx;
+		if ((em->flags & EMFL_VALID) != 0)
+			break;
+		if (filp->f_flags & O_NDELAY) {
 			spin_unlock_irqrestore(&emsgs_lock, flags);
+			return -EAGAIN;
+		}
+		nblocked_emsgs_readers++;
+
+		spin_unlock_irqrestore(&emsgs_lock, flags);
 
-			n = down_interruptible(&emsgs_sema);
+		n = down_interruptible(&emsgs_sema);
 
-			spin_lock_irqsave(&emsgs_lock, flags);
+		spin_lock_irqsave(&emsgs_lock, flags);
 
-			nblocked_emsgs_readers--;
+		nblocked_emsgs_readers--;
 
-			if (n) {
-				spin_unlock_irqrestore(&emsgs_lock, flags);
-				return -ERESTARTSYS;
-			}
-			goto loop;
-		}
-		if (em->len > cnt) {
+		if (n) {
 			spin_unlock_irqrestore(&emsgs_lock, flags);
-			return -EAGAIN;
+			return -ERESTARTSYS;
 		}
-		mp = em->msg;
-		len = em->len;
-		em->msg = NULL;
-		em->flags &= ~EMFL_VALID;
+	}
+	if (em->len > cnt) {
+		spin_unlock_irqrestore(&emsgs_lock, flags);
+		return -EAGAIN;
+	}
+	mp = em->msg;
+	len = em->len;
+	em->msg = NULL;
+	em->flags &= ~EMFL_VALID;
 
-		emsgs_head_idx++;
-		emsgs_head_idx %= ARRAY_SIZE(emsgs);
+	emsgs_head_idx++;
+	emsgs_head_idx %= ARRAY_SIZE(emsgs);
 
-		spin_unlock_irqrestore(&emsgs_lock, flags);
+	spin_unlock_irqrestore(&emsgs_lock, flags);
 
-		n = copy_to_user(buf, mp, len);
-		kfree(mp);
-		return n == 0 ? len : -EFAULT;
-	default:
-		return -EFAULT;
-	}
+	n = copy_to_user(buf, mp, len);
+	kfree(mp);
+	return n == 0 ? len : -EFAULT;
 }
 
 static const struct file_operations aoe_fops = {
-- 
1.5.3.4


  parent reply	other threads:[~2007-12-20 22:17 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-12-20 22:15 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
2007-12-20 22:15 ` [PATCH 02/13] handle multiple network paths to AoE device Ed L. Cashin
2007-12-20 22:15 ` [PATCH 03/13] mac_addr: avoid 64-bit arch compiler warnings Ed L. Cashin
2007-12-20 22:15 ` [PATCH 04/13] clean up udev configuration example Ed L. Cashin
2007-12-20 22:15 ` Ed L. Cashin [this message]
2007-12-20 22:15 ` [PATCH 06/13] user can ask driver to forget previously detected devices Ed L. Cashin
2007-12-20 22:15 ` [PATCH 07/13] dynamically allocate a capped number of skbs when necessary Ed L. Cashin
2007-12-20 22:15 ` [PATCH 08/13] only install new AoE device once Ed L. Cashin
2007-12-20 22:15 ` [PATCH 09/13] remove race between use and initialization of locks Ed L. Cashin
2007-12-22  6:00   ` Andrew Morton
2007-12-26 19:28     ` Ed L. Cashin
2007-12-26 20:25     ` [PATCH] aoe: initialize locking structures before registering char devices Ed L. Cashin
2007-12-26 20:35     ` [PATCH] aoe: document the behavior of /dev/etherd/err Ed L. Cashin
2007-12-20 22:15 ` [PATCH 10/13] add module parameter for users who need more outstanding I/O Ed L. Cashin
2007-12-20 22:15 ` [PATCH 11/13] the aoeminor doesn't need a long format Ed L. Cashin
2007-12-20 22:16 ` [PATCH 12/13] make error messages more specific Ed L. Cashin
2007-12-20 22:16 ` [PATCH 13/13] update copyright date Ed L. Cashin
2007-12-22  6:03   ` Andrew Morton
  -- strict thread matches above, loose matches on Subject: below --
2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
2007-12-07 17:48 ` [PATCH 05/13] eliminate goto and improve readability Ed L. Cashin

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