From 072f9b8b3f58807983f326e38dec3681f301f511 Mon Sep 17 00:00:00 2001
From: Michael Ellerman <michael@ellerman.id.au>
Date: Thu, 30 Jun 2005 15:16:48 +1000
Subject: [PATCH] --- yaml --- r: 4031 b: refs/heads/master c:
 ffe1b7e14e6b606bd84cab564aa2f481dbd4e418 h: refs/heads/master i:   4029:
 15d25db3cd97075e4ba8b4570b6efb9a8da75afe   4027:
 0dd3e789db5e8f9d640a2be4a55f336554851975   4023:
 218429626fdc960a4c443a279c0cebd8d18169c9   4015:
 d1628a200883352c4f88143276ab3dc006cb026a   3999:
 48ef3adb146540f3c3e3315f20178663501e820a   3967:
 f31dc674bc5ae222012748f4533e77e4220b7399 v: v3

---
 [refs]                              |  2 +-
 trunk/arch/ppc64/kernel/ItLpQueue.c | 72 ++++++++++++++++-------------
 2 files changed, 42 insertions(+), 32 deletions(-)

diff --git a/[refs] b/[refs]
index ab9282d8882d..d53c3f7280f3 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 38fcdcfe38fc3f8972c906db64cd7d540b7760e8
+refs/heads/master: ffe1b7e14e6b606bd84cab564aa2f481dbd4e418
diff --git a/trunk/arch/ppc64/kernel/ItLpQueue.c b/trunk/arch/ppc64/kernel/ItLpQueue.c
index 61a9dbdd295a..a4f32cbf5297 100644
--- a/trunk/arch/ppc64/kernel/ItLpQueue.c
+++ b/trunk/arch/ppc64/kernel/ItLpQueue.c
@@ -74,24 +74,27 @@ unsigned long ItLpQueueInProcess = 0;
 
 static struct HvLpEvent * get_next_hvlpevent(void)
 {
-	struct HvLpEvent * nextLpEvent =
-		(struct HvLpEvent *)hvlpevent_queue.xSlicCurEventPtr;
-	if (nextLpEvent->xFlags.xValid) {
+	struct HvLpEvent * event;
+	event = (struct HvLpEvent *)hvlpevent_queue.xSlicCurEventPtr;
+
+	if (event->xFlags.xValid) {
 		/* rmb() needed only for weakly consistent machines (regatta) */
 		rmb();
 		/* Set pointer to next potential event */
-		hvlpevent_queue.xSlicCurEventPtr += ((nextLpEvent->xSizeMinus1 +
-				      LpEventAlign) /
-				      LpEventAlign) *
-				      LpEventAlign;
+		hvlpevent_queue.xSlicCurEventPtr += ((event->xSizeMinus1 +
+				LpEventAlign) / LpEventAlign) * LpEventAlign;
+
 		/* Wrap to beginning if no room at end */
-		if (hvlpevent_queue.xSlicCurEventPtr > hvlpevent_queue.xSlicLastValidEventPtr)
-			hvlpevent_queue.xSlicCurEventPtr = hvlpevent_queue.xSlicEventStackPtr;
+		if (hvlpevent_queue.xSlicCurEventPtr >
+				hvlpevent_queue.xSlicLastValidEventPtr) {
+			hvlpevent_queue.xSlicCurEventPtr =
+				hvlpevent_queue.xSlicEventStackPtr;
+		}
+	} else {
+		event = NULL;
 	}
-	else
-		nextLpEvent = NULL;
 
-	return nextLpEvent;
+	return event;
 }
 
 static unsigned long spread_lpevents = NR_CPUS;
@@ -104,34 +107,41 @@ int hvlpevent_is_pending(void)
 		return 0;
 
 	next_event = (struct HvLpEvent *)hvlpevent_queue.xSlicCurEventPtr;
-	return next_event->xFlags.xValid | hvlpevent_queue.xPlicOverflowIntPending;
+
+	return next_event->xFlags.xValid |
+		hvlpevent_queue.xPlicOverflowIntPending;
 }
 
 static void hvlpevent_clear_valid(struct HvLpEvent * event)
 {
-	/* Clear the valid bit of the event
-	 * Also clear bits within this event that might
-	 * look like valid bits (on 64-byte boundaries)
+	/* Tell the Hypervisor that we're done with this event.
+	 * Also clear bits within this event that might look like valid bits.
+	 * ie. on 64-byte boundaries.
 	 */
+	struct HvLpEvent *tmp;
 	unsigned extra = ((event->xSizeMinus1 + LpEventAlign) /
 						 LpEventAlign) - 1;
+
 	switch (extra) {
 	case 3:
-	   ((struct HvLpEvent*)((char*)event+3*LpEventAlign))->xFlags.xValid=0;
+		tmp = (struct HvLpEvent*)((char*)event + 3 * LpEventAlign);
+		tmp->xFlags.xValid = 0;
 	case 2:
-	   ((struct HvLpEvent*)((char*)event+2*LpEventAlign))->xFlags.xValid=0;
+		tmp = (struct HvLpEvent*)((char*)event + 2 * LpEventAlign);
+		tmp->xFlags.xValid = 0;
 	case 1:
-	   ((struct HvLpEvent*)((char*)event+1*LpEventAlign))->xFlags.xValid=0;
-	case 0:
-		;
+		tmp = (struct HvLpEvent*)((char*)event + 1 * LpEventAlign);
+		tmp->xFlags.xValid = 0;
 	}
+
 	mb();
+
 	event->xFlags.xValid = 0;
 }
 
 void process_hvlpevents(struct pt_regs *regs)
 {
-	struct HvLpEvent * nextLpEvent;
+	struct HvLpEvent * event;
 
 	/* If we have recursed, just return */
 	if ( !set_inUse() )
@@ -143,8 +153,8 @@ void process_hvlpevents(struct pt_regs *regs)
 		BUG();
 
 	for (;;) {
-		nextLpEvent = get_next_hvlpevent();
-		if (nextLpEvent) {
+		event = get_next_hvlpevent();
+		if (event) {
 			/* Call appropriate handler here, passing
 			 * a pointer to the LpEvent.  The handler
 			 * must make a copy of the LpEvent if it
@@ -158,15 +168,15 @@ void process_hvlpevents(struct pt_regs *regs)
 			 * registered for, so no type check is necessary
 			 * here!
 			 */
-			if (nextLpEvent->xType < HvLpEvent_Type_NumTypes)
-				__get_cpu_var(hvlpevent_counts)[nextLpEvent->xType]++;
-			if (nextLpEvent->xType < HvLpEvent_Type_NumTypes &&
-					lpEventHandler[nextLpEvent->xType])
-				lpEventHandler[nextLpEvent->xType](nextLpEvent, regs);
+			if (event->xType < HvLpEvent_Type_NumTypes)
+				__get_cpu_var(hvlpevent_counts)[event->xType]++;
+			if (event->xType < HvLpEvent_Type_NumTypes &&
+					lpEventHandler[event->xType])
+				lpEventHandler[event->xType](event, regs);
 			else
-				printk(KERN_INFO "Unexpected Lp Event type=%d\n", nextLpEvent->xType );
+				printk(KERN_INFO "Unexpected Lp Event type=%d\n", event->xType );
 
-			hvlpevent_clear_valid(nextLpEvent);
+			hvlpevent_clear_valid(event);
 		} else if (hvlpevent_queue.xPlicOverflowIntPending)
 			/*
 			 * No more valid events. If overflow events are