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

- Allows reclaim to access counter without looping over processor counts.

- Allows accurate statistics on how many pages are used in a zone by
  the slab. This may become useful to balance slab allocations over
  various zones.

[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>

4 files changed, 5 insertions, 5 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 8350720f98a8..a38a11cfb483 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1318,7 +1318,7 @@ void show_free_areas(void)
                 ps.nr_writeback,
                 ps.nr_unstable,
                 nr_free_pages(),
-                ps.nr_slab,
+                global_page_state(NR_SLAB),
                 global_page_state(NR_FILE_MAPPED),
                 ps.nr_page_table_pages);
 
diff --git a/mm/slab.c b/mm/slab.c
index 0c33820038cb..5dcfb9044801 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1507,7 +1507,7 @@ static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid)
         nr_pages = (1 << cachep->gfporder);
         if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
                 atomic_add(nr_pages, &slab_reclaim_pages);
-        add_page_state(nr_slab, nr_pages);
+        add_zone_page_state(page_zone(page), NR_SLAB, nr_pages);
         for (i = 0; i < nr_pages; i++)
                 __SetPageSlab(page + i);
         return page_address(page);
@@ -1522,12 +1522,12 @@ static void kmem_freepages(struct kmem_cache *cachep, void *addr)
         struct page *page = virt_to_page(addr);
         const unsigned long nr_freed = i;
 
+        sub_zone_page_state(page_zone(page), NR_SLAB, nr_freed);
         while (i--) {
                 BUG_ON(!PageSlab(page));
                 __ClearPageSlab(page);
                 page++;
         }
-        sub_page_state(nr_slab, nr_freed);
         if (current->reclaim_state)
                 current->reclaim_state->reclaimed_slab += nr_freed;
         free_pages((unsigned long)addr, cachep->gfporder);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 0960846d649f..d6942436ac97 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1362,7 +1362,7 @@ unsigned long shrink_all_memory(unsigned long nr_pages)
         for_each_zone(zone)
                 lru_pages += zone->nr_active + zone->nr_inactive;
 
-        nr_slab = read_page_state(nr_slab);
+        nr_slab = global_page_state(NR_SLAB);
         /* If slab caches are huge, it's better to hit them first */
         while (nr_slab >= lru_pages) {
                 reclaim_state.reclaimed_slab = 0;
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 3baf4dffa62a..dc9e69209223 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -398,13 +398,13 @@ static char *vmstat_text[] = {
         "nr_anon_pages",
         "nr_mapped",
         "nr_file_pages",
+        "nr_slab",
 
         /* Page state */
         "nr_dirty",
         "nr_writeback",
         "nr_unstable",
         "nr_page_table_pages",
-        "nr_slab",
 
         "pgpgin",
         "pgpgout",