[PATCH] vm: per-zone vmscan instrumentation

To check on zone balancing, split the /proc/vmstat:pgsteal, pgreclaim pgalloc
and pgscan stats into per-zone counters.

Additionally, split the pgscan stats into pgscan_direct and pgscan_kswapd to
see who's doing how much scanning.

And add a metric for the number of slab objects which were scanned.

2 files changed, 39 insertions, 6 deletions

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 1cbccb4d226f..147870f47c03 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -288,6 +288,11 @@ static inline int is_highmem(struct zone *zone)
 	return (zone - zone->zone_pgdat->node_zones == ZONE_HIGHMEM);
 }
 
+static inline int is_normal(struct zone *zone)
+{
+	return (zone - zone->zone_pgdat->node_zones == ZONE_NORMAL);
+}
+
 /* These two functions are used to setup the per zone pages min values */
 struct ctl_table;
 struct file;
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 0b35e7111465..f58c9e68d3d8 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -98,23 +98,38 @@ struct page_state {
 	unsigned long pgpgout;		/* Disk writes */
 	unsigned long pswpin;		/* swap reads */
 	unsigned long pswpout;		/* swap writes */
-	unsigned long pgalloc;		/* page allocations */
+	unsigned long pgalloc_high;	/* page allocations */
 
+	unsigned long pgalloc_normal;
+	unsigned long pgalloc_dma;
 	unsigned long pgfree;		/* page freeings */
 	unsigned long pgactivate;	/* pages moved inactive->active */
 	unsigned long pgdeactivate;	/* pages moved active->inactive */
+
 	unsigned long pgfault;		/* faults (major+minor) */
 	unsigned long pgmajfault;	/* faults (major only) */
-
-	unsigned long pgscan;		/* pages scanned by page reclaim */
-	unsigned long pgrefill;		/* inspected in refill_inactive_zone */
-	unsigned long pgsteal;		/* total pages reclaimed */
+	unsigned long pgrefill_high;	/* inspected in refill_inactive_zone */
+	unsigned long pgrefill_normal;
+	unsigned long pgrefill_dma;
+
+	unsigned long pgsteal_high;	/* total highmem pages reclaimed */
+	unsigned long pgsteal_normal;
+	unsigned long pgsteal_dma;
+	unsigned long pgscan_kswapd_high;/* total highmem pages scanned */
+	unsigned long pgscan_kswapd_normal;
+
+	unsigned long pgscan_kswapd_dma;
+	unsigned long pgscan_direct_high;/* total highmem pages scanned */
+	unsigned long pgscan_direct_normal;
+	unsigned long pgscan_direct_dma;
 	unsigned long pginodesteal;	/* pages reclaimed via inode freeing */
-	unsigned long kswapd_steal;	/* pages reclaimed by kswapd */
 
+	unsigned long slabs_scanned;	/* slab objects scanned */
+	unsigned long kswapd_steal;	/* pages reclaimed by kswapd */
 	unsigned long kswapd_inodesteal;/* reclaimed via kswapd inode freeing */
 	unsigned long pageoutrun;	/* kswapd's calls to page reclaim */
 	unsigned long allocstall;	/* direct reclaim calls */
+
 	unsigned long pgrotated;	/* pages rotated to tail of the LRU */
 } ____cacheline_aligned;
 
@@ -131,11 +146,24 @@ extern void get_full_page_state(struct page_state *ret);
 		local_irq_restore(flags);				\
 	} while (0)
 
+
 #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 mod_page_state_zone(zone, member, delta)			\
+	do {								\
+		unsigned long flags;					\
+		local_irq_save(flags);					\
+		if (is_highmem(zone))					\
+			__get_cpu_var(page_states).member##_high += (delta);\
+		else if (is_normal(zone))				\
+			__get_cpu_var(page_states).member##_normal += (delta);\
+		else							\
+			__get_cpu_var(page_states).member##_dma += (delta);\
+		local_irq_restore(flags);				\
+	} while (0)
 
 /*
  * Manipulation of page state flags