[PATCH RFC 09/15] mm: handle book relocks on lumpy reclaim

Konstantin Khlebnikov
2012-02-15T22:57:43Z

Prepare for lock splitting in move_active_pages_to_lru() and putback_inactive_pages()
on lumpy reclaim they can put pages into different books.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
---
mm/vmscan.c | 26 ++++++++++++++++++--------
1 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 0b973ff..9a3fb72 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1335,7 +1335,10 @@ static int too_many_isolated(struct zone *zone, int file,
return isolated > inactive;
}

-static noinline_for_stack void
+/*
+ * Returns currently locked book
+ */
+static noinline_for_stack struct book *
putback_inactive_pages(struct book *book,
struct list_head *page_list)
{
@@ -1386,6 +1389,8 @@ putback_inactive_pages(struct book *book,
* To save our caller's stack, now use input list for pages to free.
*/
list_splice(&pages_to_free, page_list);
+
+ return book;
}

static noinline_for_stack void
@@ -1555,7 +1560,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct book *book,
__count_vm_events(KSWAPD_STEAL, nr_reclaimed);
__count_zone_vm_events(PGSTEAL, zone, nr_reclaimed);

- putback_inactive_pages(book, &page_list);
+ book = putback_inactive_pages(book, &page_list);

__mod_zone_page_state(zone, NR_ISOLATED_ANON, -nr_anon);
__mod_zone_page_state(zone, NR_ISOLATED_FILE, -nr_file);
@@ -1614,12 +1619,15 @@ shrink_inactive_list(unsigned long nr_to_scan, struct book *book,
*
* The downside is that we have to touch page->_count against each page.
* But we had to alter page->flags anyway.
+ *
+ * Returns currently locked book
*/

-static void move_active_pages_to_lru(struct book *book,
- struct list_head *list,
- struct list_head *pages_to_free,
- enum lru_list lru)
+static struct book *
+move_active_pages_to_lru(struct book *book,
+ struct list_head *list,
+ struct list_head *pages_to_free,
+ enum lru_list lru)
{
unsigned long pgmoved = 0;
struct page *page;
@@ -1667,6 +1675,8 @@ static void move_active_pages_to_lru(struct book *book,
__mod_zone_page_state(book_zone(book), NR_LRU_BASE + lru, pgmoved);
if (!is_active_lru(lru))
__count_vm_events(PGDEACTIVATE, pgmoved);
+
+ return book;
}

static void shrink_active_list(unsigned long nr_to_scan,
@@ -1755,9 +1765,9 @@ static void shrink_active_list(unsigned long nr_to_scan,
*/
reclaim_stat->recent_rotated[file] += nr_rotated;

- move_active_pages_to_lru(book, &l_active, &l_hold,
+ book = move_active_pages_to_lru(book, &l_active, &l_hold,
LRU_ACTIVE + file * LRU_FILE);
- move_active_pages_to_lru(book, &l_inactive, &l_hold,
+ book = move_active_pages_to_lru(book, &l_inactive, &l_hold,
LRU_BASE + file * LRU_FILE);
__mod_zone_page_state(zone, NR_ISOLATED_ANON + file, -nr_taken);
unlock_book_irq(book);