[PATCH] memory hotplug: __GFP_NOWARN is better for __kmalloc_section_memmap()

Add __GFP_NOWARN flag to calling of __alloc_pages() in
__kmalloc_section_memmap().  It can reduce noisy failure message.

In ia64, section size is 1 GB, this means that order 8 pages are necessary
for each section's memmap.  It is often very hard requirement under heavy
memory pressure as you know.  So, __alloc_pages() gives up allocation and
shows many noisy stack traces which means no page for each sections.
(Current my environment shows 32 times of stack trace....)

But, __kmalloc_section_memmap() calls vmalloc() after failure of it, and it
can succeed allocation of memmap.  So, its stack trace warning becomes just
noisy.  I suppose it shouldn't be shown.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/sparse.c b/mm/sparse.c
index 86c52ab..b3c82ba 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -211,7 +211,7 @@
 	struct page *page, *ret;
 	unsigned long memmap_size = sizeof(struct page) * nr_pages;
 
-	page = alloc_pages(GFP_KERNEL, get_order(memmap_size));
+	page = alloc_pages(GFP_KERNEL|__GFP_NOWARN, get_order(memmap_size));
 	if (page)
 		goto got_map_page;