unsigned long nr_mapped; /* From page_state */
- /* How many pages shrink_cache() should reclaim */
- int nr_to_reclaim;
-
/* Ask shrink_caches, or shrink_zone to scan at this priority */
unsigned int priority;
/* This context's GFP mask */
- unsigned int gfp_mask;
+ gfp_t gfp_mask;
int may_writepage;
- /* Can pages be swapped as part of reclaim? */
- int may_swap;
-
/* This context's SWAP_CLUSTER_MAX. If freeing memory for
* suspend, we effectively ignore SWAP_CLUSTER_MAX.
* In this context, it doesn't matter that we scan the
*
* Returns the number of slab objects which we shrunk.
*/
-static int shrink_slab(unsigned long scanned, unsigned int gfp_mask,
- unsigned long lru_pages)
+int shrink_slab(unsigned long scanned, gfp_t gfp_mask, unsigned long lru_pages)
{
struct shrinker *shrinker;
int ret = 0;
list_for_each_entry(shrinker, &shrinker_list, list) {
unsigned long long delta;
unsigned long total_scan;
+ unsigned long max_pass = (*shrinker->shrinker)(0, gfp_mask);
delta = (4 * scanned) / shrinker->seeks;
- delta *= (*shrinker->shrinker)(0, gfp_mask);
+ delta *= max_pass;
do_div(delta, lru_pages + 1);
shrinker->nr += delta;
- if (shrinker->nr < 0)
- shrinker->nr = LONG_MAX; /* It wrapped! */
+ if (shrinker->nr < 0) {
+ printk(KERN_ERR "%s: nr=%ld\n",
+ __FUNCTION__, shrinker->nr);
+ shrinker->nr = max_pass;
+ }
+
+ /*
+ * Avoid risking looping forever due to too large nr value:
+ * never try to free more than twice the estimate number of
+ * freeable entries.
+ */
+ if (shrinker->nr > max_pass * 2)
+ shrinker->nr = max_pass * 2;
total_scan = shrinker->nr;
shrinker->nr = 0;
res = mapping->a_ops->writepage(page, &wbc);
if (res < 0)
handle_write_error(mapping, page, res);
- if (res == WRITEPAGE_ACTIVATE) {
+ if (res == AOP_WRITEPAGE_ACTIVATE) {
ClearPageReclaim(page);
return PAGE_ACTIVATE;
}
if (PageWriteback(page))
goto keep_locked;
- referenced = page_referenced(page, 1, sc->priority <= 0);
+ referenced = page_referenced(page, 1);
/* In active use or really unfreeable? Activate it. */
if (referenced && page_mapping_inuse(page))
goto activate_locked;
* Anonymous process memory has backing store?
* Try to allocate it some swap space here.
*/
- if (PageAnon(page) && !PageSwapCache(page) && sc->may_swap) {
+ if (PageAnon(page) && !PageSwapCache(page)) {
if (!add_to_swap(page))
goto activate_locked;
}
#ifdef CONFIG_SWAP
if (PageSwapCache(page)) {
- swp_entry_t swap = { .val = page->private };
+ swp_entry_t swap = { .val = page_private(page) };
__delete_from_swap_cache(page);
write_unlock_irq(&mapping->tree_lock);
swap_free(swap);
page = lru_to_page(src);
prefetchw_prev_lru_page(page, src, flags);
- if (!TestClearPageLRU(page))
- BUG();
- list_del(&page->lru);
- if (get_page_testone(page)) {
- /*
- * It is being freed elsewhere
- */
- __put_page(page);
- SetPageLRU(page);
- list_add(&page->lru, src);
- continue;
- } else {
- list_add(&page->lru, dst);
+ switch (__isolate_lru_page(page)) {
+ case 1:
+ /* Succeeded to isolate page */
+ list_move(&page->lru, dst);
nr_taken++;
+ break;
+ case -ENOENT:
+ /* Not possible to isolate */
+ list_move(&page->lru, src);
+ break;
+ default:
+ BUG();
}
}
return nr_taken;
}
+static void lru_add_drain_per_cpu(void *dummy)
+{
+ lru_add_drain();
+}
+
+/*
+ * Isolate one page from the LRU lists and put it on the
+ * indicated list. Do necessary cache draining if the
+ * page is not on the LRU lists yet.
+ *
+ * Result:
+ * 0 = page not on LRU list
+ * 1 = page removed from LRU list and added to the specified list.
+ * -ENOENT = page is being freed elsewhere.
+ */
+int isolate_lru_page(struct page *page)
+{
+ int rc = 0;
+ struct zone *zone = page_zone(page);
+
+redo:
+ spin_lock_irq(&zone->lru_lock);
+ rc = __isolate_lru_page(page);
+ if (rc == 1) {
+ if (PageActive(page))
+ del_page_from_active_list(zone, page);
+ else
+ del_page_from_inactive_list(zone, page);
+ }
+ spin_unlock_irq(&zone->lru_lock);
+ if (rc == 0) {
+ /*
+ * Maybe this page is still waiting for a cpu to drain it
+ * from one of the lru lists?
+ */
+ rc = schedule_on_each_cpu(lru_add_drain_per_cpu, NULL);
+ if (rc == 0 && PageLRU(page))
+ goto redo;
+ }
+ return rc;
+}
+
/*
* shrink_cache() adds the number of pages reclaimed to sc->nr_reclaimed
*/
goto done;
max_scan -= nr_scan;
- if (current_is_kswapd())
- mod_page_state_zone(zone, pgscan_kswapd, nr_scan);
- else
- mod_page_state_zone(zone, pgscan_direct, nr_scan);
nr_freed = shrink_list(&page_list, sc);
- if (current_is_kswapd())
- mod_page_state(kswapd_steal, nr_freed);
- mod_page_state_zone(zone, pgsteal, nr_freed);
- sc->nr_to_reclaim -= nr_freed;
- spin_lock_irq(&zone->lru_lock);
+ local_irq_disable();
+ if (current_is_kswapd()) {
+ __mod_page_state_zone(zone, pgscan_kswapd, nr_scan);
+ __mod_page_state(kswapd_steal, nr_freed);
+ } else
+ __mod_page_state_zone(zone, pgscan_direct, nr_scan);
+ __mod_page_state_zone(zone, pgsteal, nr_freed);
+
+ spin_lock(&zone->lru_lock);
/*
* Put back any unfreeable pages.
*/
pagevec_release(&pvec);
}
+static inline void move_to_lru(struct page *page)
+{
+ list_del(&page->lru);
+ if (PageActive(page)) {
+ /*
+ * lru_cache_add_active checks that
+ * the PG_active bit is off.
+ */
+ ClearPageActive(page);
+ lru_cache_add_active(page);
+ } else {
+ lru_cache_add(page);
+ }
+ put_page(page);
+}
+
+/*
+ * Add isolated pages on the list back to the LRU
+ *
+ * returns the number of pages put back.
+ */
+int putback_lru_pages(struct list_head *l)
+{
+ struct page *page;
+ struct page *page2;
+ int count = 0;
+
+ list_for_each_entry_safe(page, page2, l, lru) {
+ move_to_lru(page);
+ count++;
+ }
+ return count;
+}
+
/*
* This moves pages from the active list to the inactive list.
*
if (page_mapped(page)) {
if (!reclaim_mapped ||
(total_swap_pages == 0 && PageAnon(page)) ||
- page_referenced(page, 0, sc->priority <= 0)) {
+ page_referenced(page, 0)) {
list_add(&page->lru, &l_active);
continue;
}
}
}
zone->nr_active += pgmoved;
- spin_unlock_irq(&zone->lru_lock);
- pagevec_release(&pvec);
+ spin_unlock(&zone->lru_lock);
- mod_page_state_zone(zone, pgrefill, pgscanned);
- mod_page_state(pgdeactivate, pgdeactivate);
+ __mod_page_state_zone(zone, pgrefill, pgscanned);
+ __mod_page_state(pgdeactivate, pgdeactivate);
+ local_irq_enable();
+
+ pagevec_release(&pvec);
}
/*
else
nr_inactive = 0;
- sc->nr_to_reclaim = sc->swap_cluster_max;
-
while (nr_active || nr_inactive) {
if (nr_active) {
sc->nr_to_scan = min(nr_active,
(unsigned long)sc->swap_cluster_max);
nr_inactive -= sc->nr_to_scan;
shrink_cache(zone, sc);
- if (sc->nr_to_reclaim <= 0)
- break;
}
}
for (i = 0; zones[i] != NULL; i++) {
struct zone *zone = zones[i];
- if (zone->present_pages == 0)
+ if (!populated_zone(zone))
continue;
if (!cpuset_zone_allowed(zone, __GFP_HARDWALL))
* holds filesystem locks which prevent writeout this might not work, and the
* allocation attempt will fail.
*/
-int try_to_free_pages(struct zone **zones, unsigned int gfp_mask)
+int try_to_free_pages(struct zone **zones, gfp_t gfp_mask)
{
int priority;
int ret = 0;
sc.gfp_mask = gfp_mask;
sc.may_writepage = 0;
- sc.may_swap = 1;
inc_page_state(allocstall);
sc.nr_reclaimed = 0;
sc.priority = priority;
sc.swap_cluster_max = SWAP_CLUSTER_MAX;
+ if (!priority)
+ disable_swap_token();
shrink_caches(zones, &sc);
shrink_slab(sc.nr_scanned, gfp_mask, lru_pages);
if (reclaim_state) {
total_reclaimed = 0;
sc.gfp_mask = GFP_KERNEL;
sc.may_writepage = 0;
- sc.may_swap = 1;
sc.nr_mapped = read_page_state(nr_mapped);
inc_page_state(pageoutrun);
int end_zone = 0; /* Inclusive. 0 = ZONE_DMA */
unsigned long lru_pages = 0;
+ /* The swap token gets in the way of swapout... */
+ if (!priority)
+ disable_swap_token();
+
all_zones_ok = 1;
if (nr_pages == 0) {
for (i = pgdat->nr_zones - 1; i >= 0; i--) {
struct zone *zone = pgdat->node_zones + i;
- if (zone->present_pages == 0)
+ if (!populated_zone(zone))
continue;
if (zone->all_unreclaimable &&
continue;
if (!zone_watermark_ok(zone, order,
- zone->pages_high, 0, 0, 0)) {
+ zone->pages_high, 0, 0)) {
end_zone = i;
goto scan;
}
struct zone *zone = pgdat->node_zones + i;
int nr_slab;
- if (zone->present_pages == 0)
+ if (!populated_zone(zone))
continue;
if (zone->all_unreclaimable && priority != DEF_PRIORITY)
if (nr_pages == 0) { /* Not software suspend */
if (!zone_watermark_ok(zone, order,
- zone->pages_high, end_zone, 0, 0))
+ zone->pages_high, end_zone, 0))
all_zones_ok = 0;
}
zone->temp_priority = priority;
{
pg_data_t *pgdat;
- if (zone->present_pages == 0)
+ if (!populated_zone(zone))
return;
pgdat = zone->zone_pgdat;
- if (zone_watermark_ok(zone, order, zone->pages_low, 0, 0, 0))
+ if (zone_watermark_ok(zone, order, zone->pages_low, 0, 0))
return;
if (pgdat->kswapd_max_order < order)
pgdat->kswapd_max_order = order;
}
module_init(kswapd_init)
-
-
-/*
- * Try to free up some pages from this zone through reclaim.
- */
-int zone_reclaim(struct zone *zone, unsigned int 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;
-
- 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;
-}
projects / powerpc.git / blobdiff