diff --git a/include/linux/swap.h b/include/linux/swap.h index 54eac8a39a4c11d8c760064a8f2fa987ce45d13a..5b1fdf1cff4f057a67eb1c81e487acad031a89b2 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -155,6 +155,7 @@ extern void swapin_readahead(swp_entry_t, unsigned long, struct vm_area_struct * /* linux/mm/page_alloc.c */ extern unsigned long totalram_pages; extern unsigned long totalhigh_pages; +extern unsigned long totalreserve_pages; extern long nr_swap_pages; extern unsigned int nr_free_pages(void); extern unsigned int nr_free_pages_pgdat(pg_data_t *pgdat); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index b8165e037dee9e4110cdb30e60822a9be2de9491..97d6827c7d669529fb7e5607cad4ba838d1847bf 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -51,6 +51,7 @@ nodemask_t node_possible_map __read_mostly = NODE_MASK_ALL; EXPORT_SYMBOL(node_possible_map); unsigned long totalram_pages __read_mostly; unsigned long totalhigh_pages __read_mostly; +unsigned long totalreserve_pages __read_mostly; long nr_swap_pages; int percpu_pagelist_fraction; @@ -2476,6 +2477,38 @@ void __init page_alloc_init(void) hotcpu_notifier(page_alloc_cpu_notify, 0); } +/* + * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio + * or min_free_kbytes changes. + */ +static void calculate_totalreserve_pages(void) +{ + struct pglist_data *pgdat; + unsigned long reserve_pages = 0; + int i, j; + + for_each_online_pgdat(pgdat) { + for (i = 0; i < MAX_NR_ZONES; i++) { + struct zone *zone = pgdat->node_zones + i; + unsigned long max = 0; + + /* Find valid and maximum lowmem_reserve in the zone */ + for (j = i; j < MAX_NR_ZONES; j++) { + if (zone->lowmem_reserve[j] > max) + max = zone->lowmem_reserve[j]; + } + + /* we treat pages_high as reserved pages. */ + max += zone->pages_high; + + if (max > zone->present_pages) + max = zone->present_pages; + reserve_pages += max; + } + } + totalreserve_pages = reserve_pages; +} + /* * setup_per_zone_lowmem_reserve - called whenever * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone @@ -2507,6 +2540,9 @@ static void setup_per_zone_lowmem_reserve(void) } } } + + /* update totalreserve_pages */ + calculate_totalreserve_pages(); } /* @@ -2561,6 +2597,9 @@ void setup_per_zone_pages_min(void) zone->pages_high = zone->pages_min + tmp / 2; spin_unlock_irqrestore(&zone->lru_lock, flags); } + + /* update totalreserve_pages */ + calculate_totalreserve_pages(); } /*