summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMel Gorman <mel@csn.ul.ie>2010-08-09 17:19:31 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-08-09 20:45:00 -0700
commitabe4c3b50c3f25cb1baf56036024860f12f96015 (patch)
tree20ac47ac168b30f1dde6773d103ed13432802049
parent666356297ec4e9e6594c6008803f2b1403ff7950 (diff)
vmscan: set up pagevec as late as possible in shrink_page_list()
shrink_page_list() sets up a pagevec to release pages as according as they are free. It uses significant amounts of stack on the pagevec. This patch adds pages to be freed via pagevec to a linked list which is then freed en-masse at the end. This avoids using stack in the main path that potentially calls writepage(). Signed-off-by: Mel Gorman <mel@csn.ul.ie> Reviewed-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>
-rw-r--r--mm/vmscan.c36
1 files changed, 28 insertions, 8 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 12b692164bcc..512f4630ba8c 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -622,6 +622,24 @@ static enum page_references page_check_references(struct page *page,
return PAGEREF_RECLAIM;
}
+static noinline_for_stack void free_page_list(struct list_head *free_pages)
+{
+ struct pagevec freed_pvec;
+ struct page *page, *tmp;
+
+ pagevec_init(&freed_pvec, 1);
+
+ list_for_each_entry_safe(page, tmp, free_pages, lru) {
+ list_del(&page->lru);
+ if (!pagevec_add(&freed_pvec, page)) {
+ __pagevec_free(&freed_pvec);
+ pagevec_reinit(&freed_pvec);
+ }
+ }
+
+ pagevec_free(&freed_pvec);
+}
+
/*
* shrink_page_list() returns the number of reclaimed pages
*/
@@ -630,13 +648,12 @@ static unsigned long shrink_page_list(struct list_head *page_list,
enum pageout_io sync_writeback)
{
LIST_HEAD(ret_pages);
- struct pagevec freed_pvec;
+ LIST_HEAD(free_pages);
int pgactivate = 0;
unsigned long nr_reclaimed = 0;
cond_resched();
- pagevec_init(&freed_pvec, 1);
while (!list_empty(page_list)) {
enum page_references references;
struct address_space *mapping;
@@ -811,10 +828,12 @@ static unsigned long shrink_page_list(struct list_head *page_list,
__clear_page_locked(page);
free_it:
nr_reclaimed++;
- if (!pagevec_add(&freed_pvec, page)) {
- __pagevec_free(&freed_pvec);
- pagevec_reinit(&freed_pvec);
- }
+
+ /*
+ * Is there need to periodically free_page_list? It would
+ * appear not as the counts should be low
+ */
+ list_add(&page->lru, &free_pages);
continue;
cull_mlocked:
@@ -837,9 +856,10 @@ keep:
list_add(&page->lru, &ret_pages);
VM_BUG_ON(PageLRU(page) || PageUnevictable(page));
}
+
+ free_page_list(&free_pages);
+
list_splice(&ret_pages, page_list);
- if (pagevec_count(&freed_pvec))
- __pagevec_free(&freed_pvec);
count_vm_events(PGACTIVATE, pgactivate);
return nr_reclaimed;
}