Event counters [1/3]: Basic counter functionality

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147 lines not on this page · raw message

Index: linux-2.6.15-rc5-mm3/mm/page_alloc.c
===================================================================
@@ -443,7 +443,7 @@ static void __free_pages_ok(struct page 
 
 	kernel_map_pages(page, 1 << order, 0);
 	local_irq_save(flags);
-	__mod_page_state(pgfree, 1 << order);
+	count_events(PGFREE, 1 << order);
 	free_one_page(page_zone(page), page, order);
 	local_irq_restore(flags);
 }

@@ -473,7 +473,7 @@ void fastcall __init __free_pages_bootme
 
 		arch_free_page(page, order);
 
-		mod_page_state(pgfree, 1 << order);
+		count_events(PGFREE, 1 << order);
 
 		list_add(&page->lru, &list);
 		kernel_map_pages(page, 1 << order, 0);

@@ -1030,7 +1030,7 @@ static void fastcall free_hot_cold_page(
 
 	pcp = &zone_pcp(zone, get_cpu())->pcp[cold];
 	local_irq_save(flags);
-	__inc_page_state(pgfree);
+	count_event(PGFREE);
 	list_add(&page->lru, &pcp->list);
 	pcp->count++;
 	if (pcp->count >= pcp->high) {

@@ -1097,7 +1097,7 @@ again:
 			goto failed;
 	}
 
-	__mod_page_state_zone(zone, pgalloc, 1 << order);
+	count_zone_events(PGALLOC, zone, 1 << order);
 	zone_statistics(zonelist, zone, cpu);
 	local_irq_restore(flags);
 	put_cpu();

Index: linux-2.6.15-rc5-mm3/mm/vmscan.c
===================================================================
@@ -227,7 +227,7 @@ int shrink_slab(unsigned long scanned, g
 					(nr_before - shrink_ret));
 			}
 			shrinker_stat_add(shrinker, nr_req, this_scan);
-			mod_page_state(slabs_scanned, this_scan);
+			count_events(SLABS_SCANNED, this_scan);
 			total_scan -= this_scan;
 
 			cond_resched();

@@ -567,7 +567,7 @@ keep:
 	list_splice(&ret_pages, page_list);
 	if (pagevec_count(&freed_pvec))
 		__pagevec_release_nonlru(&freed_pvec);
-	mod_page_state(pgactivate, pgactivate);
+	count_events(PGACTIVATE, pgactivate);
 	sc->nr_reclaimed += reclaimed;
 	return reclaimed;
 }

@@ -888,11 +888,11 @@ static void shrink_cache(struct zone *zo
 
 		local_irq_disable();
 		if (current_is_kswapd()) {
-			__mod_page_state_zone(zone, pgscan_kswapd, nr_scan);
-			__mod_page_state(kswapd_steal, nr_freed);
+			count_zone_events(PGSCAN_KSWAPD, zone, nr_scan);
+			count_events(KSWAPD_STEAL, nr_freed);
 		} else
-			__mod_page_state_zone(zone, pgscan_direct, nr_scan);
-		__mod_page_state_zone(zone, pgsteal, nr_freed);
+			count_zone_events(PGSCAN_DIRECT, zone, nr_scan);
+		count_events(PGACTIVATE, nr_freed);
 
 		spin_lock(&zone->lru_lock);
 		/*

@@ -1056,11 +1056,10 @@ refill_inactive_zone(struct zone *zone, 
 		}
 	}
 	zone->nr_active += pgmoved;
-	spin_unlock(&zone->lru_lock);
+	spin_unlock_irq(&zone->lru_lock);
 
-	__mod_page_state_zone(zone, pgrefill, pgscanned);
-	__mod_page_state(pgdeactivate, pgdeactivate);
-	local_irq_enable();
+	count_zone_events(PGREFILL, zone, pgscanned);
+	count_events(PGDEACTIVATE, pgdeactivate);
 
 	pagevec_release(&pvec);
 }

@@ -1182,7 +1181,7 @@ int try_to_free_pages(struct zone **zone
 	sc.gfp_mask = gfp_mask;
 	sc.may_writepage = 0;
 
-	inc_page_state(allocstall);
+	count_event(ALLOCSTALL);
 
 	for (i = 0; zones[i] != NULL; i++) {
 		struct zone *zone = zones[i];

@@ -1285,7 +1284,7 @@ loop_again:
 	sc.may_writepage = 0;
 	sc.nr_mapped = global_page_state(NR_MAPPED);
 
-	inc_page_state(pageoutrun);
+	count_event(PAGEOUTRUN);
 
 	for (i = 0; i < pgdat->nr_zones; i++) {
 		struct zone *zone = pgdat->node_zones + i;

Index: linux-2.6.15-rc5-mm3/block/ll_rw_blk.c
===================================================================
@@ -3007,9 +3007,9 @@ void submit_bio(int rw, struct bio *bio)
 	BIO_BUG_ON(!bio->bi_io_vec);
 	bio->bi_rw |= rw;
 	if (rw & WRITE)
-		mod_page_state(pgpgout, count);
+		count_events(PGPGOUT, count);
 	else
-		mod_page_state(pgpgin, count);
+		count_events(PGPGIN, count);
 
 	if (unlikely(block_dump)) {
 		char b[BDEVNAME_SIZE];

Index: linux-2.6.15-rc5-mm3/mm/page_io.c
===================================================================
@@ -101,7 +101,7 @@ int swap_writepage(struct page *page, st
 	}
 	if (wbc->sync_mode == WB_SYNC_ALL)
 		rw |= (1 << BIO_RW_SYNC);
-	inc_page_state(pswpout);
+	count_event(PSWPOUT);
 	set_page_writeback(page);
 	unlock_page(page);
 	submit_bio(rw, bio);

@@ -123,7 +123,7 @@ int swap_readpage(struct file *file, str
 		ret = -ENOMEM;
 		goto out;
 	}
-	inc_page_state(pswpin);
+	count_event(PSWPIN);
 	submit_bio(READ, bio);
 out:
 	return ret;

Index: linux-2.6.15-rc5-mm3/mm/memory.c
===================================================================
@@ -1887,7 +1887,7 @@ static int do_swap_page(struct mm_struct
 
 		/* Had to read the page from swap area: Major fault */
 		ret = VM_FAULT_MAJOR;
-		inc_page_state(pgmajfault);
+		count_event(PGMAJFAULT);
 		grab_swap_token();
 	}
 

@@ -2247,7 +2247,7 @@ int __handle_mm_fault(struct mm_struct *
 
 	__set_current_state(TASK_RUNNING);
 
-	inc_page_state(pgfault);
+	count_event(PGFAULT);
 
 	if (unlikely(is_vm_hugetlb_page(vma)))
 		return hugetlb_fault(mm, vma, address, write_access);

Index: linux-2.6.15-rc5-mm3/fs/inode.c
===================================================================
@@ -462,9 +462,9 @@ static void prune_icache(int nr_to_scan)
 	up(&iprune_sem);
 
 	if (current_is_kswapd())
-		mod_page_state(kswapd_inodesteal, reap);
+		count_events(KSWAPD_INODESTEAL, reap);
 	else
-		mod_page_state(pginodesteal, reap);
+		count_events(PGINODESTEAL, reap);
 }
 
 /*

Index: linux-2.6.15-rc5-mm3/mm/shmem.c
===================================================================
@@ -996,7 +996,7 @@ repeat:
 			spin_unlock(&info->lock);
 			/* here we actually do the io */
 			if (type && *type == VM_FAULT_MINOR) {
-				inc_page_state(pgmajfault);
+				count_event(PGMAJFAULT);
 				*type = VM_FAULT_MAJOR;
 			}
 			swappage = shmem_swapin(info, swap, idx);

Index: linux-2.6.15-rc5-mm3/mm/swap.c
===================================================================
@@ -85,7 +85,7 @@ int rotate_reclaimable_page(struct page 
 	if (PageLRU(page) && !PageActive(page)) {
 		list_del(&page->lru);
 		list_add_tail(&page->lru, &zone->inactive_list);
-		inc_page_state(pgrotated);
+		count_event(PGROTATED);
 	}
 	if (!test_clear_page_writeback(page))
 		BUG();

@@ -105,7 +105,7 @@ void fastcall activate_page(struct page 
 		del_page_from_inactive_list(zone, page);
 		SetPageActive(page);
 		add_page_to_active_list(zone, page);
-		inc_page_state(pgactivate);
+		count_event(PGACTIVATE);
 	}
 	spin_unlock_irq(&zone->lru_lock);
 }

Index: linux-2.6.15-rc5-mm3/mm/filemap.c
===================================================================
@@ -1283,7 +1283,7 @@ retry_find:
 		 */
 		if (!did_readaround) {
 			majmin = VM_FAULT_MAJOR;
-			inc_page_state(pgmajfault);
+			count_event(PGMAJFAULT);
 		}
 		did_readaround = 1;
 		ra_pages = max_sane_readahead(file->f_ra.ra_pages);

@@ -1354,7 +1354,7 @@ no_cached_page:
 page_not_uptodate:
 	if (!did_readaround) {
 		majmin = VM_FAULT_MAJOR;
-		inc_page_state(pgmajfault);
+		count_event(PGMAJFAULT);
 	}
 	lock_page(page);
 

Index: linux-2.6.15-rc5-mm3/fs/ncpfs/mmap.c
===================================================================
@@ -93,7 +93,7 @@ static struct page* ncp_file_mmap_nopage
 	 */
 	if (type)
 		*type = VM_FAULT_MAJOR;
-	inc_page_state(pgmajfault);
+	count_event(PGMAJFAULT);
 	return page;
 }
 

Index: linux-2.6.15-rc5-mm3/drivers/parisc/led.c
===================================================================
@@ -410,14 +410,12 @@ static __inline__ int led_get_net_activi
 static __inline__ int led_get_diskio_activity(void)
 {	
 	static unsigned long last_pgpgin, last_pgpgout;
-	struct page_state pgstat;
 	int changed;
 
-	get_full_page_state(&pgstat); /* get no of sectors in & out */
-
 	/* Just use a very simple calculation here. Do not care about overflow,
 	   since we only want to know if there was activity or not. */
-	changed = (pgstat.pgpgin != last_pgpgin) || (pgstat.pgpgout != last_pgpgout);
+	changed = (get_global_events(PGPGIN) != last_pgpgin) ||
+		  (get_global_events(PGPGOUT) != last_pgpgout);
 	last_pgpgin  = pgstat.pgpgin;
 	last_pgpgout = pgstat.pgpgout;
 

Index: linux-2.6.15-rc5-mm3/include/linux/mmzone.h
===================================================================
@@ -79,14 +79,6 @@ struct per_cpu_pageset {
 	s8 vm_stat_diff[NR_STAT_ITEMS];
 #endif
 
-#ifdef CONFIG_NUMA
-	unsigned long numa_hit;		/* allocated in intended node */
-	unsigned long numa_miss;	/* allocated in non intended node */
-	unsigned long numa_foreign;	/* was intended here, hit elsewhere */
-	unsigned long interleave_hit; 	/* interleaver prefered this zone */
-	unsigned long local_node;	/* allocation from local node */
-	unsigned long other_node;	/* allocation from other node */
-#endif
 } ____cacheline_aligned_in_smp;
 
 #ifdef CONFIG_NUMA

Index: linux-2.6.15-rc5-mm3/include/linux/page-flags.h
===================================================================
@@ -103,6 +103,9 @@ enum event_item { PGPGIN, PGPGOUT, PSWPI
 		FOR_ALL_ZONES(PGSCAN_DIRECT),
 		PGINODESTEAL, SLABS_SCANNED, KSWAPD_STEAL, KSWAPD_INODESTEAL,
 		PAGEOUTRUN, ALLOCSTALL, PGROTATED,
+#ifdef CONFIG_NUMA
+		NUMA_MISS, NUMA_OFF_NODE,
+#endif
 		NR_EVENT_ITEMS
 };
 

Index: linux-2.6.15-rc5-mm3/mm/mempolicy.c
===================================================================
@@ -1072,15 +1072,9 @@ static struct page *alloc_page_interleav
 					unsigned nid)
 {
 	struct zonelist *zl;
-	struct page *page;
 
 	zl = NODE_DATA(nid)->node_zonelists + gfp_zone(gfp);
-	page = __alloc_pages(gfp, order, zl);
-	if (page && page_zone(page) == zl->zones[0]) {
-		zone_pcp(zl->zones[0],get_cpu())->interleave_hit++;
-		put_cpu();
-	}
-	return page;
+	return __alloc_pages(gfp, order, zl);
 }
 
 /**

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60 lines not on this page · raw message

Index: linux-2.6.15-rc5-mm3/include/linux/mmzone.h
===================================================================
@@ -79,14 +79,6 @@ struct per_cpu_pageset {
 	s8 vm_stat_diff[NR_STAT_ITEMS];
 #endif
 
-#ifdef CONFIG_NUMA
-	unsigned long numa_hit;		/* allocated in intended node */
-	unsigned long numa_miss;	/* allocated in non intended node */
-	unsigned long numa_foreign;	/* was intended here, hit elsewhere */
-	unsigned long interleave_hit; 	/* interleaver prefered this zone */
-	unsigned long local_node;	/* allocation from local node */
-	unsigned long other_node;	/* allocation from other node */
-#endif
 } ____cacheline_aligned_in_smp;
 
 #ifdef CONFIG_NUMA

Index: linux-2.6.15-rc5-mm3/include/linux/page-flags.h
===================================================================
@@ -103,6 +103,9 @@ enum event_item { PGPGIN, PGPGOUT, PSWPI
 		FOR_ALL_ZONES(PGSCAN_DIRECT),
 		PGINODESTEAL, SLABS_SCANNED, KSWAPD_STEAL, KSWAPD_INODESTEAL,
 		PAGEOUTRUN, ALLOCSTALL, PGROTATED,
+#ifdef CONFIG_NUMA
+		NUMA_MISS, NUMA_OFF_NODE,
+#endif
 		NR_EVENT_ITEMS
 };
 

@@ -131,6 +134,8 @@ static inline void count_events(enum eve
 	__get_cpu_var(event_states).event[item] += delta;
 }
 
+extern char *vmstat_text[];
+
 #else
 /* Disable counters */
 #define get_cpu_events(e)	0L

Index: linux-2.6.15-rc5-mm3/mm/mempolicy.c
===================================================================
@@ -1072,15 +1072,9 @@ static struct page *alloc_page_interleav
 					unsigned nid)
 {
 	struct zonelist *zl;
-	struct page *page;
 
 	zl = NODE_DATA(nid)->node_zonelists + gfp_zone(gfp);
-	page = __alloc_pages(gfp, order, zl);
-	if (page && page_zone(page) == zl->zones[0]) {
-		zone_pcp(zl->zones[0],get_cpu())->interleave_hit++;
-		put_cpu();
-	}
-	return page;
+	return __alloc_pages(gfp, order, zl);
 }
 
 /**

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51 lines not on this page · raw message

Index: linux-2.6.15-rc5-mm3/drivers/base/cpu.c
===================================================================
@@ -8,6 +8,7 @@
 #include <linux/cpu.h>
 #include <linux/topology.h>
 #include <linux/device.h>
+#include <linux/page-flags.h>
 
 #include "base.h"
 

@@ -83,6 +84,26 @@ static inline void register_cpu_control(
 }
 #endif /* CONFIG_HOTPLUG_CPU */
 
+static ssize_t cpu_read_vmstat(struct sys_device * dev, char * buf)
+{
+	int i;
+	char *p = buf;
+	cpumask_t mask;
+	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
+	unsigned long v[NR_EVENT_ITEMS];
+
+	cpus_clear(mask);
+	cpu_set(cpu->sysdev.id, mask);
+	sum_events(v, &mask);
+
+	for (i = 0; i < NR_EVENT_ITEMS; i++)
+		p += sprintf(p, "%s %ld\n",
+			vmstat_text[NR_STAT_ITEMS + i], v[i]);
+	return p - buf;
+}
+static SYSDEV_ATTR(vmstat, S_IRUGO, cpu_read_vmstat, NULL);
+
+
 #ifdef CONFIG_KEXEC
 #include <linux/kexec.h>
 

@@ -138,6 +159,7 @@ int __devinit register_cpu(struct cpu *c
 	if (!error)
 		error = sysdev_create_file(&cpu->sysdev, &attr_crash_notes);
 #endif
+	sysdev_create_file(&cpu->sysdev, &attr_vmstat);
 	return error;
 }
 

index 343083f..f173e0f 100644
@@ -83,10 +83,14 @@
 struct page_state {
 	unsigned long nr_dirty;		/* Dirty writeable pages */
 	unsigned long nr_writeback;	/* Pages under writeback */
+					/* also modified from IRQ context */
 	unsigned long nr_unstable;	/* NFS unstable pages */
 	unsigned long nr_page_table_pages;/* Pages used for pagetables */
+					/* only modified from process context */
 	unsigned long nr_mapped;	/* mapped into pagetables */
+					/* only modified from process context */
 	unsigned long nr_slab;		/* In slab */
+					/* also modified from IRQ context */
 #define GET_PAGE_STATE_LAST nr_slab
 
 	/*

diff -Nur -p --exclude-from=linux-2.6.15-rc5/Documentation/dontdiff /tmp/2.6.15-rc5-mm3.orig/fs/buffer.c linux-2.6.15-rc5/fs/buffer.c
@@ -857,7 +857,7 @@ int __set_page_dirty_buffers(struct page
 		write_lock_irq(&mapping->tree_lock);
 		if (page->mapping) {	/* Race with truncate? */
 			if (mapping_cap_account_dirty(mapping))
-				inc_page_state(nr_dirty);
+				___inc_page_state(nr_dirty);
 			radix_tree_tag_set(&mapping->page_tree,
 						page_index(page),
 						PAGECACHE_TAG_DIRTY);

diff -Nur -p --exclude-from=linux-2.6.15-rc5/Documentation/dontdiff /tmp/2.6.15-rc5-mm3.orig/fs/inode.c linux-2.6.15-rc5/fs/inode.c
@@ -462,9 +462,9 @@ static void prune_icache(int nr_to_scan)
 	up(&iprune_sem);
 
 	if (current_is_kswapd())
-		mod_page_state(kswapd_inodesteal, reap);
+		__mod_page_state(kswapd_inodesteal, reap);
 	else
-		mod_page_state(pginodesteal, reap);
+		__mod_page_state(pginodesteal, reap);
 }
 
 /*

diff -Nur -p --exclude-from=linux-2.6.15-rc5/Documentation/dontdiff /tmp/2.6.15-rc5-mm3.orig/include/linux/page-flags.h linux-2.6.15-rc5/include/linux/page-flags.h
@@ -157,6 +157,7 @@ extern void get_page_state_node(struct p
 extern void get_full_page_state(struct page_state *ret);
 extern unsigned long read_page_state_offset(unsigned long offset);
 extern void mod_page_state_offset(unsigned long offset, unsigned long delta);
+extern void ___mod_page_state_offset(unsigned long offset, unsigned long delta);
 extern void __mod_page_state_offset(unsigned long offset, unsigned long delta);
 
 #define read_page_state(member) \

@@ -168,16 +169,27 @@ extern void __mod_page_state_offset(unsi
 #define __mod_page_state(member, delta)	\
 	__mod_page_state_offset(offsetof(struct page_state, member), (delta))
 
+#define ___mod_page_state(member, delta)	\
+	___mod_page_state_offset(offsetof(struct page_state, member), (delta))
+
+/* preempt/IRQ safe */
 #define inc_page_state(member)		mod_page_state(member, 1UL)
 #define dec_page_state(member)		mod_page_state(member, 0UL - 1)
 #define add_page_state(member,delta)	mod_page_state(member, (delta))
 #define sub_page_state(member,delta)	mod_page_state(member, 0UL - (delta))
 
+/* only preempt safe */
 #define __inc_page_state(member)	__mod_page_state(member, 1UL)
 #define __dec_page_state(member)	__mod_page_state(member, 0UL - 1)
 #define __add_page_state(member,delta)	__mod_page_state(member, (delta))
 #define __sub_page_state(member,delta)	__mod_page_state(member, 0UL - (delta))
 
+/* preempt/IRQ unsafe (plain inc/dec operations) */
+#define ___inc_page_state(member)	___mod_page_state(member, 1UL)
+#define ___dec_page_state(member)	___mod_page_state(member, 0UL - 1)
+#define ___add_page_state(member,delta)	___mod_page_state(member, (delta))
+#define ___sub_page_state(member,delta)	___mod_page_state(member, 0UL - (delta))
+
 #define page_state(member) (*__page_state(offsetof(struct page_state, member)))
 
 #define state_zone_offset(zone, member)					\

@@ -194,6 +206,11 @@ extern void __mod_page_state_offset(unsi
 	offset;								\
 })
 
+#define ___mod_page_state_zone(zone, member, delta)			\
+ do {									\
+	___mod_page_state_offset(state_zone_offset(zone, member), (delta)); \
+ } while (0)
+
 #define __mod_page_state_zone(zone, member, delta)			\
  do {									\
 	__mod_page_state_offset(state_zone_offset(zone, member), (delta)); \

diff -Nur -p --exclude-from=linux-2.6.15-rc5/Documentation/dontdiff /tmp/2.6.15-rc5-mm3.orig/mm/memory.c linux-2.6.15-rc5/mm/memory.c
@@ -116,7 +116,7 @@ static void free_pte_range(struct mmu_ga
 	pmd_clear(pmd);
 	pte_lock_deinit(page);
 	pte_free_tlb(tlb, page);
-	dec_page_state(nr_page_table_pages);
+	__dec_page_state(nr_page_table_pages);
 	tlb->mm->nr_ptes--;
 }
 

@@ -302,7 +302,10 @@ int __pte_alloc(struct mm_struct *mm, pm
 		pte_free(new);
 	} else {
 		mm->nr_ptes++;
-		inc_page_state(nr_page_table_pages);
+		/* nr_page_table_pages is never touched by interrupt 
+		 * context, so its not necessary to disable them.
+		 */
+		__inc_page_state(nr_page_table_pages);
 		pmd_populate(mm, pmd, new);
 	}
 	spin_unlock(&mm->page_table_lock);

diff -Nur -p --exclude-from=linux-2.6.15-rc5/Documentation/dontdiff /tmp/2.6.15-rc5-mm3.orig/mm/page_alloc.c linux-2.6.15-rc5/mm/page_alloc.c
@@ -443,7 +443,7 @@ static void __free_pages_ok(struct page 
 
 	kernel_map_pages(page, 1 << order, 0);
 	local_irq_save(flags);
-	__mod_page_state(pgfree, 1 << order);
+	___mod_page_state(pgfree, 1 << order);
 	free_one_page(page_zone(page), page, order);
 	local_irq_restore(flags);
 }

@@ -753,7 +753,7 @@ static void fastcall free_hot_cold_page(
 
 	pcp = &zone_pcp(zone, get_cpu())->pcp[cold];
 	local_irq_save(flags);
-	__inc_page_state(pgfree);
+	___inc_page_state(pgfree);
 	list_add(&page->lru, &pcp->list);
 	pcp->count++;
 	if (pcp->count >= pcp->high) {

@@ -820,7 +820,7 @@ again:
 			goto failed;
 	}
 
-	__mod_page_state_zone(zone, pgalloc, 1 << order);
+	___mod_page_state_zone(zone, pgalloc, 1 << order);
 	zone_statistics(zonelist, zone, cpu);
 	local_irq_restore(flags);
 	put_cpu();

@@ -1375,8 +1375,16 @@ unsigned long read_page_state_offset(uns
 	return ret;
 }
 
+
 void __mod_page_state_offset(unsigned long offset, unsigned long delta)
 {
+	preempt_disable();
+	___mod_page_state_offset(offset, delta);
+	preempt_enable();
+}
+
+void ___mod_page_state_offset(unsigned long offset, unsigned long delta)
+{
 	void *ptr;
 
 	ptr = &__get_cpu_var(page_states);

diff -Nur -p --exclude-from=linux-2.6.15-rc5/Documentation/dontdiff /tmp/2.6.15-rc5-mm3.orig/mm/page-writeback.c linux-2.6.15-rc5/mm/page-writeback.c
@@ -632,7 +632,7 @@ int __set_page_dirty_nobuffers(struct pa
 			if (mapping2) { /* Race with truncate? */
 				BUG_ON(mapping2 != mapping);
 				if (mapping_cap_account_dirty(mapping))
-					inc_page_state(nr_dirty);
+					___inc_page_state(nr_dirty);
 				radix_tree_tag_set(&mapping->page_tree,
 					page_index(page), PAGECACHE_TAG_DIRTY);
 			}

diff -Nur -p --exclude-from=linux-2.6.15-rc5/Documentation/dontdiff /tmp/2.6.15-rc5-mm3.orig/mm/rmap.c linux-2.6.15-rc5/mm/rmap.c
@@ -453,7 +453,8 @@ static void __page_set_anon_rmap(struct 
 
 	/*
 	 * nr_mapped state can be updated without turning off
-	 * interrupts because it is not modified via interrupt.
+	 * interrupts because it is not modified via interrupt. 
+	 * But it must be guarded against preemption.
 	 */
 	__inc_page_state(nr_mapped);
 }

diff -Nur -p --exclude-from=linux-2.6.15-rc5/Documentation/dontdiff /tmp/2.6.15-rc5-mm3.orig/mm/swap.c linux-2.6.15-rc5/mm/swap.c
@@ -85,7 +85,7 @@ int rotate_reclaimable_page(struct page 
 	if (PageLRU(page) && !PageActive(page)) {
 		list_del(&page->lru);
 		list_add_tail(&page->lru, &zone->inactive_list);
-		inc_page_state(pgrotated);
+		___inc_page_state(pgrotated);
 	}
 	if (!test_clear_page_writeback(page))
 		BUG();

@@ -105,7 +105,7 @@ void fastcall activate_page(struct page 
 		del_page_from_inactive_list(zone, page);
 		SetPageActive(page);
 		add_page_to_active_list(zone, page);
-		inc_page_state(pgactivate);
+		___inc_page_state(pgactivate);
 	}
 	spin_unlock_irq(&zone->lru_lock);
 }

diff -Nur -p --exclude-from=linux-2.6.15-rc5/Documentation/dontdiff /tmp/2.6.15-rc5-mm3.orig/mm/vmscan.c linux-2.6.15-rc5/mm/vmscan.c
@@ -1058,8 +1058,8 @@ refill_inactive_zone(struct zone *zone, 
 	zone->nr_active += pgmoved;
 	spin_unlock(&zone->lru_lock);
 
-	__mod_page_state_zone(zone, pgrefill, pgscanned);
-	__mod_page_state(pgdeactivate, pgdeactivate);
+	___mod_page_state_zone(zone, pgrefill, pgscanned);
+	___mod_page_state(pgdeactivate, pgdeactivate);
 	local_irq_enable();
 
 	pagevec_release(&pvec);

@@ -1182,7 +1182,7 @@ int try_to_free_pages(struct zone **zone
 	sc.gfp_mask = gfp_mask;
 	sc.may_writepage = 0;
 
-	inc_page_state(allocstall);
+	__inc_page_state(allocstall);
 
 	for (i = 0; zones[i] != NULL; i++) {
 		struct zone *zone = zones[i];

@@ -1285,7 +1285,7 @@ loop_again:
 	sc.may_writepage = 0;
 	sc.nr_mapped = read_page_state(nr_mapped);
 
-	inc_page_state(pageoutrun);
+	__inc_page_state(pageoutrun);
 
 	for (i = 0; i < pgdat->nr_zones; i++) {
 		struct zone *zone = pgdat->node_zones + i;