-
-
-/*
- * Try to free up some pages from this zone through reclaim.
- */
-int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
-{
- struct scan_control sc;
- int nr_pages = 1 << order;
- int total_reclaimed = 0;
-
- /* The reclaim may sleep, so don't do it if sleep isn't allowed */
- if (!(gfp_mask & __GFP_WAIT))
- return 0;
- if (zone->all_unreclaimable)
- return 0;
-
- sc.gfp_mask = gfp_mask;
- sc.may_writepage = 0;
- sc.may_swap = 0;
- sc.nr_mapped = read_page_state(nr_mapped);
- sc.nr_scanned = 0;
- sc.nr_reclaimed = 0;
- /* scan at the highest priority */
- sc.priority = 0;
- disable_swap_token();
-
- if (nr_pages > SWAP_CLUSTER_MAX)
- sc.swap_cluster_max = nr_pages;
- else
- sc.swap_cluster_max = SWAP_CLUSTER_MAX;
-
- /* Don't reclaim the zone if there are other reclaimers active */
- if (atomic_read(&zone->reclaim_in_progress) > 0)
- goto out;
-
- shrink_zone(zone, &sc);
- total_reclaimed = sc.nr_reclaimed;
-
- out:
- return total_reclaimed;
-}
-
-asmlinkage long sys_set_zone_reclaim(unsigned int node, unsigned int zone,
- unsigned int state)
-{
- struct zone *z;
- int i;
-
- if (!capable(CAP_SYS_ADMIN))
- return -EACCES;
-
- if (node >= MAX_NUMNODES || !node_online(node))
- return -EINVAL;
-
- /* This will break if we ever add more zones */
- if (!(zone & (1<<ZONE_DMA|1<<ZONE_NORMAL|1<<ZONE_HIGHMEM)))
- return -EINVAL;
-
- for (i = 0; i < MAX_NR_ZONES; i++) {
- if (!(zone & 1<<i))
- continue;
-
- z = &NODE_DATA(node)->node_zones[i];
-
- if (state)
- z->reclaim_pages = 1;
- else
- z->reclaim_pages = 0;
- }
-
- return 0;
-}