---

yaml --- r: 72232 b: refs/heads/master c: a98ce5c h: refs/heads/master v: v3
git-mirror · Oct 23, 2007 · 2f4ac6d · 2f4ac6d
1 parent 6856c2b
commit 2f4ac6d
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Showing 2 changed files with 19 additions and 3 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 48d2268473a66fe3aa78fb13b09ee59d6ee95073
+refs/heads/master: a98ce5c6feead6bfedefabd46cb3d7f5be148d9a
diff --git a/trunk/kernel/irq/manage.c b/trunk/kernel/irq/manage.c
@@ -29,12 +29,28 @@
 void synchronize_irq(unsigned int irq)
 {
 	struct irq_desc *desc = irq_desc + irq;
+	unsigned int status;
 
 	if (irq >= NR_IRQS)
 		return;
 
-	while (desc->status & IRQ_INPROGRESS)
-		cpu_relax();
+	do {
+		unsigned long flags;
+
+		/*
+		 * Wait until we're out of the critical section.  This might
+		 * give the wrong answer due to the lack of memory barriers.
+		 */
+		while (desc->status & IRQ_INPROGRESS)
+			cpu_relax();
+
+		/* Ok, that indicated we're done: double-check carefully. */
+		spin_lock_irqsave(&desc->lock, flags);
+		status = desc->status;
+		spin_unlock_irqrestore(&desc->lock, flags);
+
+		/* Oops, that failed? */
+	} while (status & IRQ_INPROGRESS);
 }
 EXPORT_SYMBOL(synchronize_irq);