From 179e96395b1f01e95ebe1ff5ef306b810dbbd147 Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Wed, 22 Mar 2006 00:08:18 -0800 Subject: [PATCH] [PATCH] vmscan: scan_control cleanup Initialise as much of scan_control as possible at the declaration site. This tidies things up a bit and assures us that all unmentioned fields are zeroed out. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmscan.c | 108 ++++++++++++++++++++++++++++++---------------------- 1 file changed, 62 insertions(+), 46 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index f7c4f37c3b1..5feef4d4650 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1431,13 +1431,14 @@ int try_to_free_pages(struct zone **zones, gfp_t gfp_mask) int ret = 0; int total_scanned = 0, total_reclaimed = 0; struct reclaim_state *reclaim_state = current->reclaim_state; - struct scan_control sc; unsigned long lru_pages = 0; int i; - - sc.gfp_mask = gfp_mask; - sc.may_writepage = !laptop_mode; - sc.may_swap = 1; + struct scan_control sc = { + .gfp_mask = gfp_mask, + .may_writepage = !laptop_mode, + .swap_cluster_max = SWAP_CLUSTER_MAX, + .may_swap = 1, + }; inc_page_state(allocstall); @@ -1455,7 +1456,6 @@ int try_to_free_pages(struct zone **zones, gfp_t gfp_mask) sc.nr_mapped = read_page_state(nr_mapped); sc.nr_scanned = 0; sc.nr_reclaimed = 0; - sc.swap_cluster_max = SWAP_CLUSTER_MAX; if (!priority) disable_swap_token(); shrink_caches(priority, zones, &sc); @@ -1478,7 +1478,8 @@ int try_to_free_pages(struct zone **zones, gfp_t gfp_mask) * that's undesirable in laptop mode, where we *want* lumpy * writeout. So in laptop mode, write out the whole world. */ - if (total_scanned > sc.swap_cluster_max + sc.swap_cluster_max/2) { + if (total_scanned > sc.swap_cluster_max + + sc.swap_cluster_max / 2) { wakeup_pdflush(laptop_mode ? 0 : total_scanned); sc.may_writepage = 1; } @@ -1532,14 +1533,16 @@ static int balance_pgdat(pg_data_t *pgdat, int nr_pages, int order) int i; int total_scanned, total_reclaimed; struct reclaim_state *reclaim_state = current->reclaim_state; - struct scan_control sc; + struct scan_control sc = { + .gfp_mask = GFP_KERNEL, + .may_swap = 1, + .swap_cluster_max = nr_pages ? nr_pages : SWAP_CLUSTER_MAX, + }; loop_again: total_scanned = 0; total_reclaimed = 0; - sc.gfp_mask = GFP_KERNEL; - sc.may_writepage = !laptop_mode; - sc.may_swap = 1; + sc.may_writepage = !laptop_mode, sc.nr_mapped = read_page_state(nr_mapped); inc_page_state(pageoutrun); @@ -1621,7 +1624,6 @@ scan: zone->prev_priority = priority; sc.nr_scanned = 0; sc.nr_reclaimed = 0; - sc.swap_cluster_max = nr_pages? nr_pages : SWAP_CLUSTER_MAX; shrink_zone(priority, zone, &sc); reclaim_state->reclaimed_slab = 0; nr_slab = shrink_slab(sc.nr_scanned, GFP_KERNEL, @@ -1869,46 +1871,21 @@ int zone_reclaim_interval __read_mostly = 30*HZ; /* * Try to free up some pages from this zone through reclaim. */ -int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order) +static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order) { - int nr_pages; + const int nr_pages = 1 << order; struct task_struct *p = current; struct reclaim_state reclaim_state; - struct scan_control sc; - cpumask_t mask; - int node_id; int priority; - - if (time_before(jiffies, - zone->last_unsuccessful_zone_reclaim + zone_reclaim_interval)) - return 0; - - if (!(gfp_mask & __GFP_WAIT) || - zone->all_unreclaimable || - atomic_read(&zone->reclaim_in_progress) > 0 || - (p->flags & PF_MEMALLOC)) - return 0; - - node_id = zone->zone_pgdat->node_id; - mask = node_to_cpumask(node_id); - if (!cpus_empty(mask) && node_id != numa_node_id()) - return 0; - - sc.may_writepage = !!(zone_reclaim_mode & RECLAIM_WRITE); - sc.may_swap = !!(zone_reclaim_mode & RECLAIM_SWAP); - sc.nr_scanned = 0; - sc.nr_reclaimed = 0; - sc.nr_mapped = read_page_state(nr_mapped); - sc.gfp_mask = gfp_mask; + 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), + .swap_cluster_max = max(nr_pages, SWAP_CLUSTER_MAX), + .gfp_mask = gfp_mask, + }; disable_swap_token(); - - nr_pages = 1 << order; - if (nr_pages > SWAP_CLUSTER_MAX) - sc.swap_cluster_max = nr_pages; - else - sc.swap_cluster_max = SWAP_CLUSTER_MAX; - cond_resched(); /* * We need to be able to allocate from the reserves for RECLAIM_SWAP @@ -1949,5 +1926,44 @@ int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order) return sc.nr_reclaimed >= nr_pages; } + +int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order) +{ + cpumask_t mask; + int node_id; + + /* + * Do not reclaim if there was a recent unsuccessful attempt at zone + * reclaim. In that case we let allocations go off node for the + * zone_reclaim_interval. Otherwise we would scan for each off-node + * page allocation. + */ + if (time_before(jiffies, + zone->last_unsuccessful_zone_reclaim + zone_reclaim_interval)) + return 0; + + /* + * Avoid concurrent zone reclaims, do not reclaim in a zone that does + * not have reclaimable pages and if we should not delay the allocation + * then do not scan. + */ + if (!(gfp_mask & __GFP_WAIT) || + zone->all_unreclaimable || + atomic_read(&zone->reclaim_in_progress) > 0 || + (current->flags & PF_MEMALLOC)) + return 0; + + /* + * Only run zone reclaim on the local zone or on zones that do not + * have associated processors. This will favor the local processor + * over remote processors and spread off node memory allocations + * as wide as possible. + */ + node_id = zone->zone_pgdat->node_id; + mask = node_to_cpumask(node_id); + if (!cpus_empty(mask) && node_id != numa_node_id()) + return 0; + return __zone_reclaim(zone, gfp_mask, order); +} #endif -- 2.20.1