From 889980b8e3fcc901aaf05b5974c8ed375cfce5c7 Mon Sep 17 00:00:00 2001
From: Michael Ellerman <michael@ellerman.id.au>
Date: Thu, 30 Jun 2005 15:17:02 +1000
Subject: [PATCH] --- yaml --- r: 4032 b: refs/heads/master c:
 719d1cd86780c156f954fc34f34481adac197aec h: refs/heads/master v: v3

---
 [refs]                                      |  2 +-
 trunk/arch/ppc64/kernel/ItLpQueue.c         | 38 ++-------------------
 trunk/include/asm-ppc64/iSeries/ItLpQueue.h |  2 +-
 3 files changed, 4 insertions(+), 38 deletions(-)

diff --git a/[refs] b/[refs]
index d53c3f7280f3..c830deb1add0 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ffe1b7e14e6b606bd84cab564aa2f481dbd4e418
+refs/heads/master: 719d1cd86780c156f954fc34f34481adac197aec
diff --git a/trunk/arch/ppc64/kernel/ItLpQueue.c b/trunk/arch/ppc64/kernel/ItLpQueue.c
index a4f32cbf5297..4231861288a3 100644
--- a/trunk/arch/ppc64/kernel/ItLpQueue.c
+++ b/trunk/arch/ppc64/kernel/ItLpQueue.c
@@ -42,35 +42,8 @@ static char *event_types[HvLpEvent_Type_NumTypes] = {
 	"Virtual I/O"
 };
 
-static __inline__ int set_inUse(void)
-{
-	int t;
-	u32 * inUseP = &hvlpevent_queue.xInUseWord;
-
-	__asm__ __volatile__("\n\
-1:	lwarx	%0,0,%2		\n\
-	cmpwi	0,%0,0		\n\
-	li	%0,0		\n\
-	bne-	2f		\n\
-	addi	%0,%0,1		\n\
-	stwcx.	%0,0,%2		\n\
-	bne-	1b		\n\
-2:	eieio"
-	: "=&r" (t), "=m" (hvlpevent_queue.xInUseWord)
-	: "r" (inUseP), "m" (hvlpevent_queue.xInUseWord)
-	: "cc");
-
-	return t;
-}
-
-static __inline__ void clear_inUse(void)
-{
-	hvlpevent_queue.xInUseWord = 0;
-}
-
 /* Array of LpEvent handler functions */
 extern LpEventHandler lpEventHandler[HvLpEvent_Type_NumTypes];
-unsigned long ItLpQueueInProcess = 0;
 
 static struct HvLpEvent * get_next_hvlpevent(void)
 {
@@ -144,14 +117,9 @@ void process_hvlpevents(struct pt_regs *regs)
 	struct HvLpEvent * event;
 
 	/* If we have recursed, just return */
-	if ( !set_inUse() )
+	if (!spin_trylock(&hvlpevent_queue.lock))
 		return;
 
-	if (ItLpQueueInProcess == 0)
-		ItLpQueueInProcess = 1;
-	else
-		BUG();
-
 	for (;;) {
 		event = get_next_hvlpevent();
 		if (event) {
@@ -187,9 +155,7 @@ void process_hvlpevents(struct pt_regs *regs)
 			break;
 	}
 
-	ItLpQueueInProcess = 0;
-	mb();
-	clear_inUse();
+	spin_unlock(&hvlpevent_queue.lock);
 }
 
 static int set_spread_lpevents(char *str)
diff --git a/trunk/include/asm-ppc64/iSeries/ItLpQueue.h b/trunk/include/asm-ppc64/iSeries/ItLpQueue.h
index 51db08852dba..69b26ad74135 100644
--- a/trunk/include/asm-ppc64/iSeries/ItLpQueue.h
+++ b/trunk/include/asm-ppc64/iSeries/ItLpQueue.h
@@ -69,7 +69,7 @@ struct hvlpevent_queue {
 	char	*xSlicEventStackPtr;	// 0x20
 	u8	xIndex;			// 0x28 unique sequential index.
 	u8	xSlicRsvd[3];		// 0x29-2b
-	u32	xInUseWord;		// 0x2C
+	spinlock_t	lock;
 };
 
 extern struct hvlpevent_queue hvlpevent_queue;