Subject: zoned vm counters: conversion of nr_mapped to per zone counter From: Christoph Lameter nr_mapped is important because it allows a determination of how many pages of a zone are not mapped, which would allow a more efficient means of determining when we need to reclaim memory in a zone. We take the nr_mapped field out of the page state structure and define a new per zone counter named NR_FILE_MAPPED (the anonymous pages will be split off from NR_MAPPED in the next patch). We replace the use of nr_mapped in various kernel locations. This avoids the looping over all processors in try_to_free_pages(), writeback, reclaim (swap + zone reclaim). Signed-off-by: Christoph Lameter Index: linux-2.6.17-mm1/arch/i386/mm/pgtable.c =================================================================== --- linux-2.6.17-mm1.orig/arch/i386/mm/pgtable.c 2006-06-17 18:49:35.000000000 -0700 +++ linux-2.6.17-mm1/arch/i386/mm/pgtable.c 2006-06-21 08:06:14.414759983 -0700 @@ -61,7 +61,7 @@ void show_mem(void) get_page_state(&ps); printk(KERN_INFO "%lu pages dirty\n", ps.nr_dirty); printk(KERN_INFO "%lu pages writeback\n", ps.nr_writeback); - printk(KERN_INFO "%lu pages mapped\n", ps.nr_mapped); + printk(KERN_INFO "%lu pages mapped\n", global_page_state(NR_FILE_MAPPED)); printk(KERN_INFO "%lu pages slab\n", ps.nr_slab); printk(KERN_INFO "%lu pages pagetables\n", ps.nr_page_table_pages); } Index: linux-2.6.17-mm1/drivers/base/node.c =================================================================== --- linux-2.6.17-mm1.orig/drivers/base/node.c 2006-06-17 18:49:35.000000000 -0700 +++ linux-2.6.17-mm1/drivers/base/node.c 2006-06-21 08:06:14.415736485 -0700 @@ -53,8 +53,6 @@ static ssize_t node_read_meminfo(struct ps.nr_dirty = 0; if ((long)ps.nr_writeback < 0) ps.nr_writeback = 0; - if ((long)ps.nr_mapped < 0) - ps.nr_mapped = 0; if ((long)ps.nr_slab < 0) ps.nr_slab = 0; @@ -83,7 +81,7 @@ static ssize_t node_read_meminfo(struct nid, K(i.freeram - i.freehigh), nid, K(ps.nr_dirty), nid, K(ps.nr_writeback), - nid, K(ps.nr_mapped), + nid, K(node_page_state(nid, NR_FILE_MAPPED)), nid, K(ps.nr_slab)); n += hugetlb_report_node_meminfo(nid, buf + n); return n; Index: linux-2.6.17-mm1/fs/proc/proc_misc.c =================================================================== --- linux-2.6.17-mm1.orig/fs/proc/proc_misc.c 2006-06-17 18:49:35.000000000 -0700 +++ linux-2.6.17-mm1/fs/proc/proc_misc.c 2006-06-21 08:06:14.416712987 -0700 @@ -190,7 +190,7 @@ static int meminfo_read_proc(char *page, K(i.freeswap), K(ps.nr_dirty), K(ps.nr_writeback), - K(ps.nr_mapped), + K(global_page_state(NR_FILE_MAPPED)), K(ps.nr_slab), K(allowed), K(committed), Index: linux-2.6.17-mm1/include/linux/mmzone.h =================================================================== --- linux-2.6.17-mm1.orig/include/linux/mmzone.h 2006-06-21 08:04:57.507406207 -0700 +++ linux-2.6.17-mm1/include/linux/mmzone.h 2006-06-21 08:06:14.418665992 -0700 @@ -48,6 +48,9 @@ struct zone_padding { #endif enum zone_stat_item { + NR_FILE_MAPPED, /* mapped into pagetables. + only modified from process context */ + NR_VM_ZONE_STAT_ITEMS }; struct per_cpu_pages { Index: linux-2.6.17-mm1/mm/page_alloc.c =================================================================== --- linux-2.6.17-mm1.orig/mm/page_alloc.c 2006-06-21 08:04:57.509359211 -0700 +++ linux-2.6.17-mm1/mm/page_alloc.c 2006-06-21 08:06:14.419642494 -0700 @@ -1314,7 +1314,7 @@ void show_free_areas(void) ps.nr_unstable, nr_free_pages(), ps.nr_slab, - ps.nr_mapped, + global_page_state(NR_FILE_MAPPED), ps.nr_page_table_pages); for_each_zone(zone) { Index: linux-2.6.17-mm1/mm/page-writeback.c =================================================================== --- linux-2.6.17-mm1.orig/mm/page-writeback.c 2006-06-17 18:49:35.000000000 -0700 +++ linux-2.6.17-mm1/mm/page-writeback.c 2006-06-21 08:06:14.420618996 -0700 @@ -111,7 +111,7 @@ static void get_writeback_state(struct w { wbs->nr_dirty = read_page_state(nr_dirty); wbs->nr_unstable = read_page_state(nr_unstable); - wbs->nr_mapped = read_page_state(nr_mapped); + wbs->nr_mapped = global_page_state(NR_FILE_MAPPED); wbs->nr_writeback = read_page_state(nr_writeback); } Index: linux-2.6.17-mm1/mm/rmap.c =================================================================== --- linux-2.6.17-mm1.orig/mm/rmap.c 2006-06-17 18:49:35.000000000 -0700 +++ linux-2.6.17-mm1/mm/rmap.c 2006-06-21 08:06:14.421595498 -0700 @@ -493,7 +493,7 @@ static void __page_set_anon_rmap(struct * nr_mapped state can be updated without turning off * interrupts because it is not modified via interrupt. */ - __inc_page_state(nr_mapped); + __inc_zone_page_state(page, NR_FILE_MAPPED); } /** @@ -537,7 +537,7 @@ void page_add_new_anon_rmap(struct page void page_add_file_rmap(struct page *page) { if (atomic_inc_and_test(&page->_mapcount)) - __inc_page_state(nr_mapped); + __inc_zone_page_state(page, NR_FILE_MAPPED); } /** @@ -569,7 +569,7 @@ void page_remove_rmap(struct page *page) */ if (page_test_and_clear_dirty(page)) set_page_dirty(page); - __dec_page_state(nr_mapped); + __dec_zone_page_state(page, NR_FILE_MAPPED); } } Index: linux-2.6.17-mm1/mm/vmscan.c =================================================================== --- linux-2.6.17-mm1.orig/mm/vmscan.c 2006-06-17 18:49:35.000000000 -0700 +++ linux-2.6.17-mm1/mm/vmscan.c 2006-06-21 08:06:14.422572000 -0700 @@ -972,7 +972,7 @@ unsigned long try_to_free_pages(struct z } for (priority = DEF_PRIORITY; priority >= 0; priority--) { - sc.nr_mapped = read_page_state(nr_mapped); + sc.nr_mapped = global_page_state(NR_FILE_MAPPED); sc.nr_scanned = 0; if (!priority) disable_swap_token(); @@ -1062,7 +1062,7 @@ loop_again: total_scanned = 0; nr_reclaimed = 0; sc.may_writepage = !laptop_mode; - sc.nr_mapped = read_page_state(nr_mapped); + sc.nr_mapped = global_page_state(NR_FILE_MAPPED); inc_page_state(pageoutrun); @@ -1412,7 +1412,7 @@ static int __zone_reclaim(struct zone *z struct scan_control sc = { .may_writepage = !!(zone_reclaim_mode & RECLAIM_WRITE), .may_swap = !!(zone_reclaim_mode & RECLAIM_SWAP), - .nr_mapped = read_page_state(nr_mapped), + .nr_mapped = global_page_state(NR_FILE_MAPPED), .swap_cluster_max = max_t(unsigned long, nr_pages, SWAP_CLUSTER_MAX), .gfp_mask = gfp_mask, Index: linux-2.6.17-mm1/mm/vmstat.c =================================================================== --- linux-2.6.17-mm1.orig/mm/vmstat.c 2006-06-21 08:04:57.514241722 -0700 +++ linux-2.6.17-mm1/mm/vmstat.c 2006-06-21 08:06:14.423548502 -0700 @@ -463,13 +463,13 @@ struct seq_operations fragmentation_op = static char *vmstat_text[] = { /* Zoned VM counters */ + "nr_mapped", /* Page state */ "nr_dirty", "nr_writeback", "nr_unstable", "nr_page_table_pages", - "nr_mapped", "nr_slab", "pgpgin", Index: linux-2.6.17-mm1/include/linux/vmstat.h =================================================================== --- linux-2.6.17-mm1.orig/include/linux/vmstat.h 2006-06-21 08:04:57.512288718 -0700 +++ linux-2.6.17-mm1/include/linux/vmstat.h 2006-06-22 08:10:13.219810354 -0700 @@ -25,8 +25,6 @@ struct page_state { unsigned long nr_writeback; /* Pages under writeback */ unsigned long nr_unstable; /* NFS unstable pages */ unsigned long nr_page_table_pages;/* Pages used for pagetables */ - unsigned long nr_mapped; /* mapped into pagetables. - * only modified from process context */ unsigned long nr_slab; /* In slab */ #define GET_PAGE_STATE_LAST nr_slab