lkml.org 
[lkml]   [2008]   [Jul]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[resend][PATCH -mm] split_lru: fix pagevec_move_tail() doesn't treat unevictable page

Agghh!
I am really stupid. I forgot CCed Andrew ;-)

So, I resend this.


--------------------------------------
even under writebacking, page can move to unevictable list.
so shouldn't pagevec_move_tail() check unevictable?

if pagevec_move_tail() doesn't PageUnevictable(),
below race can occur.


CPU1 CPU2
==================================================================
1. rotate_reclaimable_page()
2. PageUnevictable(page) return 0
3. local_irq_save()
4. pagevec_move_tail()
SetPageUnevictable() //mlock?
move to unevictable list
5. spin_lock(&zone->lru_lock);
6. list_move_tail(); (move to inactive list)



Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>

---
mm/swap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

Index: b/mm/swap.c
===================================================================
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -116,7 +116,7 @@ static void pagevec_move_tail(struct pag
zone = pagezone;
spin_lock(&zone->lru_lock);
}
- if (PageLRU(page) && !PageActive(page)) {
+ if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
int lru = page_is_file_cache(page);
list_move_tail(&page->lru, &zone->lru[lru].list);
pgmoved++;





\
 
 \ /
  Last update: 2008-07-01 10:31    [W:0.084 / U:0.100 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site