[PATCH] zoned vm counters: conversion of nr_bounce to per zone counter

Conversion of nr_bounce to a per zone counter

nr_bounce is only used for proc output.  So it could be left as an event
counter.  However, the event counters may not be accurate and nr_bounce is
categorizing types of pages in a zone.  So we really need this to also be a
per zone counter.

[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/base/node.c

@@ -65,6 +65,7 @@ static ssize_t node_read_meminfo(struct sys_device * dev, char * buf)
 		       "Node %d AnonPages:    %8lu kB\n"
 		       "Node %d PageTables:   %8lu kB\n"
 		       "Node %d NFS Unstable: %8lu kB\n"
+		       "Node %d Bounce:       %8lu kB\n"
 		       "Node %d Slab:         %8lu kB\n",
 		       nid, K(i.totalram),
 		       nid, K(i.freeram),
@@ -82,6 +83,7 @@ static ssize_t node_read_meminfo(struct sys_device * dev, char * buf)
 		       nid, K(node_page_state(nid, NR_ANON_PAGES)),
 		       nid, K(node_page_state(nid, NR_PAGETABLE)),
 		       nid, K(node_page_state(nid, NR_UNSTABLE_NFS)),
+		       nid, K(node_page_state(nid, NR_BOUNCE)),
 		       nid, K(node_page_state(nid, NR_SLAB)));
 	n += hugetlb_report_node_meminfo(nid, buf + n);
 	return n;

fs/proc/proc_misc.c

@@ -171,6 +171,7 @@ static int meminfo_read_proc(char *page, char **start, off_t off,
 		"Slab:         %8lu kB\n"
 		"PageTables:   %8lu kB\n"
 		"NFS Unstable: %8lu kB\n"
+		"Bounce:       %8lu kB\n"
 		"CommitLimit:  %8lu kB\n"
 		"Committed_AS: %8lu kB\n"
 		"VmallocTotal: %8lu kB\n"
@@ -196,6 +197,7 @@ static int meminfo_read_proc(char *page, char **start, off_t off,
 		K(global_page_state(NR_SLAB)),
 		K(global_page_state(NR_PAGETABLE)),
 		K(global_page_state(NR_UNSTABLE_NFS)),
+		K(global_page_state(NR_BOUNCE)),
 		K(allowed),
 		K(committed),
 		(unsigned long)VMALLOC_TOTAL >> 10,

include/linux/mmzone.h

@@ -56,6 +56,7 @@ enum zone_stat_item {
 	NR_FILE_DIRTY,
 	NR_WRITEBACK,
 	NR_UNSTABLE_NFS,	/* NFS unstable pages */
+	NR_BOUNCE,
 	NR_VM_ZONE_STAT_ITEMS };
 
 struct per_cpu_pages {

include/linux/vmstat.h

@@ -67,7 +67,6 @@ struct page_state {
 	unsigned long allocstall;	/* direct reclaim calls */
 
 	unsigned long pgrotated;	/* pages rotated to tail of the LRU */
-	unsigned long nr_bounce;	/* pages for bounce buffers */
 };
 
 extern void get_full_page_state(struct page_state *ret);

mm/highmem.c

@@ -315,8 +315,8 @@ static void bounce_end_io(struct bio *bio, mempool_t *pool, int err)
 		if (bvec->bv_page == org_vec->bv_page)
 			continue;
 
-		mempool_free(bvec->bv_page, pool);	
-		dec_page_state(nr_bounce);
+		dec_zone_page_state(bvec->bv_page, NR_BOUNCE);
+		mempool_free(bvec->bv_page, pool);
 	}
 
 	bio_endio(bio_orig, bio_orig->bi_size, err);
@@ -397,7 +397,7 @@ static void __blk_queue_bounce(request_queue_t *q, struct bio **bio_orig,
 		to->bv_page = mempool_alloc(pool, q->bounce_gfp);
 		to->bv_len = from->bv_len;
 		to->bv_offset = from->bv_offset;
-		inc_page_state(nr_bounce);
+		inc_zone_page_state(to->bv_page, NR_BOUNCE);
 
 		if (rw == WRITE) {
 			char *vto, *vfrom;

mm/vmstat.c

@@ -381,6 +381,7 @@ static char *vmstat_text[] = {
 	"nr_dirty",
 	"nr_writeback",
 	"nr_unstable",
+	"nr_bounce",
 
 	/* Event counters */
 	"pgpgin",
@@ -428,7 +429,6 @@ static char *vmstat_text[] = {
 	"allocstall",
 
 	"pgrotated",
-	"nr_bounce",
 };
 
 /*