vmscan: set up pagevec as late as possible in shrink_inactive_list()

shrink_inactive_list() sets up a pagevec to release unfreeable pages.  It
uses significant amounts of stack doing this.  This patch splits
shrink_inactive_list() to take the stack usage out of the main path so
that callers to writepage() do not contain an unused pagevec on the stack.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michael Rubin <mrubin@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mel Gorman 2010-08-09 17:19:30 -07:00 committed by Linus Torvalds
parent d4debc66d1
commit 666356297e

View File

@ -1132,20 +1132,66 @@ static int too_many_isolated(struct zone *zone, int file,
return isolated > inactive;
}
/*
* TODO: Try merging with migrations version of putback_lru_pages
*/
static noinline_for_stack void
putback_lru_pages(struct zone *zone, struct zone_reclaim_stat *reclaim_stat,
unsigned long nr_anon, unsigned long nr_file,
struct list_head *page_list)
{
struct page *page;
struct pagevec pvec;
pagevec_init(&pvec, 1);
/*
* Put back any unfreeable pages.
*/
spin_lock(&zone->lru_lock);
while (!list_empty(page_list)) {
int lru;
page = lru_to_page(page_list);
VM_BUG_ON(PageLRU(page));
list_del(&page->lru);
if (unlikely(!page_evictable(page, NULL))) {
spin_unlock_irq(&zone->lru_lock);
putback_lru_page(page);
spin_lock_irq(&zone->lru_lock);
continue;
}
SetPageLRU(page);
lru = page_lru(page);
add_page_to_lru_list(zone, page, lru);
if (is_active_lru(lru)) {
int file = is_file_lru(lru);
reclaim_stat->recent_rotated[file]++;
}
if (!pagevec_add(&pvec, page)) {
spin_unlock_irq(&zone->lru_lock);
__pagevec_release(&pvec);
spin_lock_irq(&zone->lru_lock);
}
}
__mod_zone_page_state(zone, NR_ISOLATED_ANON, -nr_anon);
__mod_zone_page_state(zone, NR_ISOLATED_FILE, -nr_file);
spin_unlock_irq(&zone->lru_lock);
pagevec_release(&pvec);
}
/*
* shrink_inactive_list() is a helper for shrink_zone(). It returns the number
* of reclaimed pages
*/
static unsigned long shrink_inactive_list(unsigned long nr_to_scan,
struct zone *zone, struct scan_control *sc,
int priority, int file)
static noinline_for_stack unsigned long
shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
struct scan_control *sc, int priority, int file)
{
LIST_HEAD(page_list);
struct pagevec pvec;
unsigned long nr_scanned;
unsigned long nr_reclaimed = 0;
struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
struct page *page;
unsigned long nr_taken;
unsigned long nr_active;
unsigned int count[NR_LRU_LISTS] = { 0, };
@ -1161,8 +1207,6 @@ static unsigned long shrink_inactive_list(unsigned long nr_to_scan,
}
pagevec_init(&pvec, 1);
lru_add_drain();
spin_lock_irq(&zone->lru_lock);
@ -1192,8 +1236,10 @@ static unsigned long shrink_inactive_list(unsigned long nr_to_scan,
*/
}
if (nr_taken == 0)
goto done;
if (nr_taken == 0) {
spin_unlock_irq(&zone->lru_lock);
return 0;
}
nr_active = clear_active_flags(&page_list, count);
__count_vm_events(PGDEACTIVATE, nr_active);
@ -1244,40 +1290,7 @@ static unsigned long shrink_inactive_list(unsigned long nr_to_scan,
__count_vm_events(KSWAPD_STEAL, nr_reclaimed);
__count_zone_vm_events(PGSTEAL, zone, nr_reclaimed);
spin_lock(&zone->lru_lock);
/*
* Put back any unfreeable pages.
*/
while (!list_empty(&page_list)) {
int lru;
page = lru_to_page(&page_list);
VM_BUG_ON(PageLRU(page));
list_del(&page->lru);
if (unlikely(!page_evictable(page, NULL))) {
spin_unlock_irq(&zone->lru_lock);
putback_lru_page(page);
spin_lock_irq(&zone->lru_lock);
continue;
}
SetPageLRU(page);
lru = page_lru(page);
add_page_to_lru_list(zone, page, lru);
if (is_active_lru(lru)) {
int file = is_file_lru(lru);
reclaim_stat->recent_rotated[file]++;
}
if (!pagevec_add(&pvec, page)) {
spin_unlock_irq(&zone->lru_lock);
__pagevec_release(&pvec);
spin_lock_irq(&zone->lru_lock);
}
}
__mod_zone_page_state(zone, NR_ISOLATED_ANON, -nr_anon);
__mod_zone_page_state(zone, NR_ISOLATED_FILE, -nr_file);
done:
spin_unlock_irq(&zone->lru_lock);
pagevec_release(&pvec);
putback_lru_pages(zone, reclaim_stat, nr_anon, nr_file, &page_list);
return nr_reclaimed;
}