1 files changed, 195 insertions, 99 deletions

diff --git a/arch/ppc64/kernel/ItLpQueue.c b/arch/ppc64/kernel/ItLpQueue.c
index cdea00d7707f..4231861288a3 100644
--- a/arch/ppc64/kernel/ItLpQueue.c
+++ b/arch/ppc64/kernel/ItLpQueue.c
@@ -1,7 +1,7 @@
 /*
  * ItLpQueue.c
  * Copyright (C) 2001 Mike Corrigan  IBM Corporation
- * 
+ *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
@@ -11,156 +11,252 @@
 #include <linux/stddef.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
+#include <linux/bootmem.h>
+#include <linux/seq_file.h>
+#include <linux/proc_fs.h>
 #include <asm/system.h>
 #include <asm/paca.h>
 #include <asm/iSeries/ItLpQueue.h>
 #include <asm/iSeries/HvLpEvent.h>
 #include <asm/iSeries/HvCallEvent.h>
 
-static __inline__ int set_inUse( struct ItLpQueue * lpQueue )
-{
-	int t;
-	u32 * inUseP = &(lpQueue->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" (lpQueue->xInUseWord)
-	: "r" (inUseP), "m" (lpQueue->xInUseWord)
-	: "cc");
-
-	return t;
-}
+/*
+ * The LpQueue is used to pass event data from the hypervisor to
+ * the partition.  This is where I/O interrupt events are communicated.
+ *
+ * It is written to by the hypervisor so cannot end up in the BSS.
+ */
+struct hvlpevent_queue hvlpevent_queue __attribute__((__section__(".data")));
 
-static __inline__ void clear_inUse( struct ItLpQueue * lpQueue )
-{
-	lpQueue->xInUseWord = 0;
-}
+DEFINE_PER_CPU(unsigned long[HvLpEvent_Type_NumTypes], hvlpevent_counts);
+
+static char *event_types[HvLpEvent_Type_NumTypes] = {
+	"Hypervisor",
+	"Machine Facilities",
+	"Session Manager",
+	"SPD I/O",
+	"Virtual Bus",
+	"PCI I/O",
+	"RIO I/O",
+	"Virtual Lan",
+	"Virtual I/O"
+};
 
 /* Array of LpEvent handler functions */
 extern LpEventHandler lpEventHandler[HvLpEvent_Type_NumTypes];
-unsigned long ItLpQueueInProcess = 0;
 
-struct HvLpEvent * ItLpQueue_getNextLpEvent( struct ItLpQueue * lpQueue )
+static struct HvLpEvent * get_next_hvlpevent(void)
 {
-	struct HvLpEvent * nextLpEvent = 
-		(struct HvLpEvent *)lpQueue->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 */
-		lpQueue->xSlicCurEventPtr += ((nextLpEvent->xSizeMinus1 +
-				      LpEventAlign ) /
-				      LpEventAlign ) *
-				      LpEventAlign;
+		hvlpevent_queue.xSlicCurEventPtr += ((event->xSizeMinus1 +
+				LpEventAlign) / LpEventAlign) * LpEventAlign;
+
 		/* Wrap to beginning if no room at end */
-		if (lpQueue->xSlicCurEventPtr > lpQueue->xSlicLastValidEventPtr)
-			lpQueue->xSlicCurEventPtr = lpQueue->xSlicEventStackPtr;
+		if (hvlpevent_queue.xSlicCurEventPtr >
+				hvlpevent_queue.xSlicLastValidEventPtr) {
+			hvlpevent_queue.xSlicCurEventPtr =
+				hvlpevent_queue.xSlicEventStackPtr;
+		}
+	} else {
+		event = NULL;
 	}
-	else 
-		nextLpEvent = NULL;
 
-	return nextLpEvent;
+	return event;
 }
 
-int ItLpQueue_isLpIntPending( struct ItLpQueue * lpQueue )
+static unsigned long spread_lpevents = NR_CPUS;
+
+int hvlpevent_is_pending(void)
 {
-	int retval = 0;
-	struct HvLpEvent * nextLpEvent;
-	if ( lpQueue ) {
-		nextLpEvent = (struct HvLpEvent *)lpQueue->xSlicCurEventPtr;
-		retval = nextLpEvent->xFlags.xValid | lpQueue->xPlicOverflowIntPending;
-	}
-	return retval;
+	struct HvLpEvent *next_event;
+
+	if (smp_processor_id() >= spread_lpevents)
+		return 0;
+
+	next_event = (struct HvLpEvent *)hvlpevent_queue.xSlicCurEventPtr;
+
+	return next_event->xFlags.xValid |
+		hvlpevent_queue.xPlicOverflowIntPending;
 }
 
-void ItLpQueue_clearValid( struct HvLpEvent * event )
+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)
-   	 */
-	unsigned extra = (( event->xSizeMinus1 + LpEventAlign ) /
-						 LpEventAlign ) - 1;
-	switch ( extra ) {
-	  case 3:
-	   ((struct HvLpEvent*)((char*)event+3*LpEventAlign))->xFlags.xValid=0;
-	  case 2:
-	   ((struct HvLpEvent*)((char*)event+2*LpEventAlign))->xFlags.xValid=0;
-	  case 1:
-	   ((struct HvLpEvent*)((char*)event+1*LpEventAlign))->xFlags.xValid=0;
-	  case 0:
-	   ;	
+	/* 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:
+		tmp = (struct HvLpEvent*)((char*)event + 3 * LpEventAlign);
+		tmp->xFlags.xValid = 0;
+	case 2:
+		tmp = (struct HvLpEvent*)((char*)event + 2 * LpEventAlign);
+		tmp->xFlags.xValid = 0;
+	case 1:
+		tmp = (struct HvLpEvent*)((char*)event + 1 * LpEventAlign);
+		tmp->xFlags.xValid = 0;
 	}
+
 	mb();
+
 	event->xFlags.xValid = 0;
 }
 
-unsigned ItLpQueue_process( struct ItLpQueue * lpQueue, struct pt_regs *regs )
+void process_hvlpevents(struct pt_regs *regs)
 {
-	unsigned numIntsProcessed = 0;
-	struct HvLpEvent * nextLpEvent;
+	struct HvLpEvent * event;
 
 	/* If we have recursed, just return */
-	if ( !set_inUse( lpQueue ) )
-		return 0;
-	
-	if (ItLpQueueInProcess == 0)
-		ItLpQueueInProcess = 1;
-	else
-		BUG();
+	if (!spin_trylock(&hvlpevent_queue.lock))
+		return;
 
 	for (;;) {
-		nextLpEvent = ItLpQueue_getNextLpEvent( lpQueue );
-		if ( nextLpEvent ) {
-			/* Count events to return to caller
-			 * and count processed events in lpQueue
- 			 */
-			++numIntsProcessed;
-			lpQueue->xLpIntCount++;		
-			/* Call appropriate handler here, passing 
+		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
 			 * needs it in a bottom half. (perhaps for
 			 * an ACK)
-			 *	
-			 *  Handlers are responsible for ACK processing 
+			 *
+			 *  Handlers are responsible for ACK processing
 			 *
 			 * The Hypervisor guarantees that LpEvents will
 			 * only be delivered with types that we have
 			 * registered for, so no type check is necessary
 			 * here!
-  			 */
-			if ( nextLpEvent->xType < HvLpEvent_Type_NumTypes )
-				lpQueue->xLpIntCountByType[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 );
-			
-			ItLpQueue_clearValid( nextLpEvent );
-		} else if ( lpQueue->xPlicOverflowIntPending )
+				printk(KERN_INFO "Unexpected Lp Event type=%d\n", event->xType );
+
+			hvlpevent_clear_valid(event);
+		} else if (hvlpevent_queue.xPlicOverflowIntPending)
 			/*
 			 * No more valid events. If overflow events are
 			 * pending process them
 			 */
-			HvCallEvent_getOverflowLpEvents( lpQueue->xIndex);
+			HvCallEvent_getOverflowLpEvents(hvlpevent_queue.xIndex);
 		else
 			break;
 	}
 
-	ItLpQueueInProcess = 0;
-	mb();
-	clear_inUse( lpQueue );
+	spin_unlock(&hvlpevent_queue.lock);
+}
+
+static int set_spread_lpevents(char *str)
+{
+	unsigned long val = simple_strtoul(str, NULL, 0);
+
+	/*
+	 * The parameter is the number of processors to share in processing
+	 * lp events.
+	 */
+	if (( val > 0) && (val <= NR_CPUS)) {
+		spread_lpevents = val;
+		printk("lpevent processing spread over %ld processors\n", val);
+	} else {
+		printk("invalid spread_lpevents %ld\n", val);
+	}
 
-	get_paca()->lpevent_count += numIntsProcessed;
+	return 1;
+}
+__setup("spread_lpevents=", set_spread_lpevents);
+
+void setup_hvlpevent_queue(void)
+{
+	void *eventStack;
+
+	/*
+	 * Allocate a page for the Event Stack. The Hypervisor needs the
+	 * absolute real address, so we subtract out the KERNELBASE and add
+	 * in the absolute real address of the kernel load area.
+	 */
+	eventStack = alloc_bootmem_pages(LpEventStackSize);
+	memset(eventStack, 0, LpEventStackSize);
+
+	/* Invoke the hypervisor to initialize the event stack */
+	HvCallEvent_setLpEventStack(0, eventStack, LpEventStackSize);
+
+	hvlpevent_queue.xSlicEventStackPtr = (char *)eventStack;
+	hvlpevent_queue.xSlicCurEventPtr = (char *)eventStack;
+	hvlpevent_queue.xSlicLastValidEventPtr = (char *)eventStack +
+					(LpEventStackSize - LpEventMaxSize);
+	hvlpevent_queue.xIndex = 0;
+}
+
+static int proc_lpevents_show(struct seq_file *m, void *v)
+{
+	int cpu, i;
+	unsigned long sum;
+	static unsigned long cpu_totals[NR_CPUS];
+
+	/* FIXME: do we care that there's no locking here? */
+	sum = 0;
+	for_each_online_cpu(cpu) {
+		cpu_totals[cpu] = 0;
+		for (i = 0; i < HvLpEvent_Type_NumTypes; i++) {
+			cpu_totals[cpu] += per_cpu(hvlpevent_counts, cpu)[i];
+		}
+		sum += cpu_totals[cpu];
+	}
+
+	seq_printf(m, "LpEventQueue 0\n");
+	seq_printf(m, "  events processed:\t%lu\n", sum);
+
+	for (i = 0; i < HvLpEvent_Type_NumTypes; ++i) {
+		sum = 0;
+		for_each_online_cpu(cpu) {
+			sum += per_cpu(hvlpevent_counts, cpu)[i];
+		}
+
+		seq_printf(m, "    %-20s %10lu\n", event_types[i], sum);
+	}
+
+	seq_printf(m, "\n  events processed by processor:\n");
+
+	for_each_online_cpu(cpu) {
+		seq_printf(m, "    CPU%02d  %10lu\n", cpu, cpu_totals[cpu]);
+	}
+
+	return 0;
+}
+
+static int proc_lpevents_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, proc_lpevents_show, NULL);
+}
 
-	return numIntsProcessed;
+static struct file_operations proc_lpevents_operations = {
+	.open		= proc_lpevents_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static int __init proc_lpevents_init(void)
+{
+	struct proc_dir_entry *e;
+
+	e = create_proc_entry("iSeries/lpevents", S_IFREG|S_IRUGO, NULL);
+	if (e)
+		e->proc_fops = &proc_lpevents_operations;
+
+	return 0;
 }
+__initcall(proc_lpevents_init);
+