Commit 885036d3 authored Nov 13, 2005 by Kirill Korotaev Committed by Linus Torvalds Nov 13, 2005

[PATCH] mm: __GFP_NOFAIL fix



In __alloc_pages():

if ((p->flags & (PF_MEMALLOC | PF_MEMDIE)) && !in_interrupt()) {
         /* go through the zonelist yet again, ignoring mins */
         for (i = 0; zones[i] != NULL; i++) {
                 struct zone *z = zones[i];

                 page = buffered_rmqueue(z, order, gfp_mask);
                 if (page) {
                         zone_statistics(zonelist, z);
                         goto got_pg;
                 }
         }
         goto nopage;                <<<< HERE!!! FAIL...
}

kswapd (which has PF_MEMALLOC flag) can fail to allocate memory even when
it allocates it with __GFP_NOFAIL flag.

Signed-Off-By: Pavel Emelianov <xemul@sw.ru>
Signed-Off-By: Denis Lunev <den@sw.ru>
Signed-Off-By: Kirill Korotaev <dev@sw.ru>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent d4d28dd4

mm/page_alloc.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -895,6 +895,7 @@ __alloc_pages(gfp_t gfp_mask, unsigned int order,
		if (((p->flags & PF_MEMALLOC) \|\| unlikely(test_thread_flag(TIF_MEMDIE)))
		&& !in_interrupt()) {
		if (!(gfp_mask & __GFP_NOMEMALLOC)) {
		nofail_alloc:
		/* go through the zonelist yet again, ignoring mins */
		for (i = 0; (z = zones[i]) != NULL; i++) {
		if (!cpuset_zone_allowed(z, gfp_mask))
		@@ -903,6 +904,10 @@ __alloc_pages(gfp_t gfp_mask, unsigned int order,
		if (page)
		goto got_pg;
		}
		if (gfp_mask & __GFP_NOFAIL) {
		blk_congestion_wait(WRITE, HZ/50);
		goto nofail_alloc;
		}
		}
		goto nopage;
		}