[PATCH] allow PF_MEMALLOC tasks to directly reclaim pages

[Marcelo Tosatti]

Linus,

Currently __alloc_pages() does not allow PF_MEMALLOC tasks to free clean
inactive pages.

This is senseless --- if the allocation has __GFP_WAIT set, its ok to grab
the pagemap_lru_lock/pagecache_lock/etc.

I checked all possible codepaths after reclaim_page() and they are ok.

The following patch fixes that.

--- linux/mm/page_alloc.c.orig	Fri Apr 27 05:59:35 2001
+++ linux/mm/page_alloc.c	Fri Apr 27 05:59:48 2001
@@ -295,8 +295,7 @@
 	 * Can we take pages directly from the inactive_clean
 	 * list?
 	 */
-	if (order == 0 && (gfp_mask & __GFP_WAIT) &&
-			!(current->flags & PF_MEMALLOC))
+	if (order == 0 && (gfp_mask & __GFP_WAIT))
 		direct_reclaim = 1;
 
 	/*