From: Christoph Lameter Conversion of nr_writeback to per zone counter Avoids per processor loop during writeback state determination. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton --- arch/i386/mm/pgtable.c | 4 +--- drivers/base/node.c | 5 +---- fs/proc/proc_misc.c | 2 +- include/linux/mmzone.h | 1 + include/linux/page-flags.h | 9 ++++----- mm/page-writeback.c | 2 +- mm/page_alloc.c | 6 +++--- 7 files changed, 12 insertions(+), 17 deletions(-) diff -puN arch/i386/mm/pgtable.c~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter arch/i386/mm/pgtable.c --- devel/arch/i386/mm/pgtable.c~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter 2006-06-09 15:17:44.000000000 -0700 +++ devel-akpm/arch/i386/mm/pgtable.c 2006-06-09 15:17:44.000000000 -0700 @@ -30,7 +30,6 @@ void show_mem(void) struct page *page; pg_data_t *pgdat; unsigned long i; - struct page_state ps; unsigned long flags; printk(KERN_INFO "Mem-info:\n"); @@ -58,9 +57,8 @@ void show_mem(void) printk(KERN_INFO "%d pages shared\n", shared); printk(KERN_INFO "%d pages swap cached\n", cached); - get_page_state(&ps); printk(KERN_INFO "%lu pages dirty\n", global_page_state(NR_DIRTY)); - printk(KERN_INFO "%lu pages writeback\n", ps.nr_writeback); + printk(KERN_INFO "%lu pages writeback\n", global_page_state(NR_WRITEBACK)); printk(KERN_INFO "%lu pages mapped\n", global_page_state(NR_MAPPED)); printk(KERN_INFO "%lu pages slab\n", global_page_state(NR_SLAB)); printk(KERN_INFO "%lu pages pagetables\n", global_page_state(NR_PAGETABLE)); diff -puN drivers/base/node.c~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter drivers/base/node.c --- devel/drivers/base/node.c~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter 2006-06-09 15:17:44.000000000 -0700 +++ devel-akpm/drivers/base/node.c 2006-06-09 15:17:44.000000000 -0700 @@ -53,9 +53,6 @@ static ssize_t node_read_meminfo(struct for (j = 0; j < NR_STAT_ITEMS; j++) nr[j] = node_page_state(nid, j); - /* Check for negative values in these approximate counters */ - if ((long)ps.nr_writeback < 0) - ps.nr_writeback = 0; n = sprintf(buf, "\n" "Node %d MemTotal: %8lu kB\n" @@ -82,7 +79,7 @@ static ssize_t node_read_meminfo(struct nid, K(i.totalram - i.totalhigh), nid, K(i.freeram - i.freehigh), nid, K(nr[NR_DIRTY]), - nid, K(ps.nr_writeback), + nid, K(nr[NR_WRITEBACK]), nid, K(nr[NR_MAPPED]), nid, K(nr[NR_PAGECACHE]), nid, K(nr[NR_SLAB])); diff -puN fs/proc/proc_misc.c~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter fs/proc/proc_misc.c --- devel/fs/proc/proc_misc.c~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter 2006-06-09 15:17:44.000000000 -0700 +++ devel-akpm/fs/proc/proc_misc.c 2006-06-09 15:17:44.000000000 -0700 @@ -189,7 +189,7 @@ static int meminfo_read_proc(char *page, K(i.totalswap), K(i.freeswap), K(global_page_state(NR_DIRTY)), - K(ps.nr_writeback), + K(global_page_state(NR_WRITEBACK)), K(global_page_state(NR_MAPPED)), K(global_page_state(NR_SLAB)), K(allowed), diff -puN include/linux/mmzone.h~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter include/linux/mmzone.h --- devel/include/linux/mmzone.h~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter 2006-06-09 15:17:44.000000000 -0700 +++ devel-akpm/include/linux/mmzone.h 2006-06-09 15:17:44.000000000 -0700 @@ -53,6 +53,7 @@ enum zone_stat_item { NR_SLAB, /* used by slab allocator */ NR_PAGETABLE, /* used for pagetables */ NR_DIRTY, + NR_WRITEBACK, NR_STAT_ITEMS }; struct per_cpu_pages { diff -puN include/linux/page-flags.h~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter include/linux/page-flags.h --- devel/include/linux/page-flags.h~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter 2006-06-09 15:17:44.000000000 -0700 +++ devel-akpm/include/linux/page-flags.h 2006-06-09 15:17:44.000000000 -0700 @@ -117,7 +117,6 @@ * commented here. */ struct page_state { - unsigned long nr_writeback; /* Pages under writeback */ unsigned long nr_unstable; /* NFS unstable pages */ #define GET_PAGE_STATE_LAST nr_unstable @@ -347,7 +346,7 @@ void dec_zone_page_state(struct page *, do { \ if (!test_and_set_bit(PG_writeback, \ &(page)->flags)) \ - inc_page_state(nr_writeback); \ + inc_zone_page_state(page, NR_WRITEBACK); \ } while (0) #define TestSetPageWriteback(page) \ ({ \ @@ -355,14 +354,14 @@ void dec_zone_page_state(struct page *, ret = test_and_set_bit(PG_writeback, \ &(page)->flags); \ if (!ret) \ - inc_page_state(nr_writeback); \ + inc_zone_page_state(page, NR_WRITEBACK); \ ret; \ }) #define ClearPageWriteback(page) \ do { \ if (test_and_clear_bit(PG_writeback, \ &(page)->flags)) \ - dec_page_state(nr_writeback); \ + dec_zone_page_state(page, NR_WRITEBACK); \ } while (0) #define TestClearPageWriteback(page) \ ({ \ @@ -370,7 +369,7 @@ void dec_zone_page_state(struct page *, ret = test_and_clear_bit(PG_writeback, \ &(page)->flags); \ if (ret) \ - dec_page_state(nr_writeback); \ + dec_zone_page_state(page, NR_WRITEBACK); \ ret; \ }) diff -puN mm/page_alloc.c~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter mm/page_alloc.c --- devel/mm/page_alloc.c~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter 2006-06-09 15:17:44.000000000 -0700 +++ devel-akpm/mm/page_alloc.c 2006-06-09 15:17:44.000000000 -0700 @@ -614,7 +614,7 @@ static int rmqueue_bulk(struct zone *zon } char *vm_stat_item_descr[NR_STAT_ITEMS] = { - "mapped", "pagecache", "slab", "pagetable", "dirty" + "mapped", "pagecache", "slab", "pagetable", "dirty", "writeback" }; /* @@ -1720,7 +1720,7 @@ void show_free_areas(void) active, inactive, global_page_state(NR_DIRTY), - ps.nr_writeback, + global_page_state(NR_WRITEBACK), ps.nr_unstable, nr_free_pages(), global_page_state(NR_SLAB), @@ -2717,9 +2717,9 @@ static char *vmstat_text[] = { "nr_slab", "nr_page_table_pages", "nr_dirty", + "nr_writeback", /* Page state */ - "nr_writeback", "nr_unstable", "pgpgin", diff -puN mm/page-writeback.c~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter mm/page-writeback.c --- devel/mm/page-writeback.c~zoned-vm-counters-conversion-of-nr_writeback-to-per-zone-counter 2006-06-09 15:17:44.000000000 -0700 +++ devel-akpm/mm/page-writeback.c 2006-06-09 15:17:44.000000000 -0700 @@ -112,7 +112,7 @@ static void get_writeback_state(struct w wbs->nr_dirty = global_page_state(NR_DIRTY); wbs->nr_unstable = read_page_state(nr_unstable); wbs->nr_mapped = global_page_state(NR_MAPPED); - wbs->nr_writeback = read_page_state(nr_writeback); + wbs->nr_writeback = global_page_state(NR_WRITEBACK); } /* _