[PATCH] adjust gfp mask passed on nested vmalloc() invocation (v2)

[Jan Beulich]

- avoid wasting more precious resources (DMA or DMA32 pools), when
  being called through vmalloc_32{,_user}()
- explicitly allow using high memory here even if the outer allocation
  request doesn't allow it, unless is collides with __GFP_ZERO

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>
Cc: Hugh Dickins <hugh.dickins@xxxxxxxxxxxxx>

---
 mm/vmalloc.c |    7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

--- linux-2.6.32-rc3/mm/vmalloc.c	2009-10-05 11:59:56.000000000 +0200
+++ 2.6.32-rc3-vmalloc-nested-gfp/mm/vmalloc.c	2009-10-07 14:39:38.000000000 +0200
@@ -1410,6 +1410,7 @@ static void *__vmalloc_area_node(struct 
 {
 	struct page **pages;
 	unsigned int nr_pages, array_size, i;
+	gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
 
 	nr_pages = (area->size - PAGE_SIZE) >> PAGE_SHIFT;
 	array_size = (nr_pages * sizeof(struct page *));
@@ -1417,13 +1418,11 @@ static void *__vmalloc_area_node(struct 
 	area->nr_pages = nr_pages;
 	/* Please note that the recursion is strictly bounded. */
 	if (array_size > PAGE_SIZE) {
-		pages = __vmalloc_node(array_size, gfp_mask | __GFP_ZERO,
+		pages = __vmalloc_node(array_size, nested_gfp | __GFP_HIGHMEM,
 				PAGE_KERNEL, node, caller);
 		area->flags |= VM_VPAGES;
 	} else {
-		pages = kmalloc_node(array_size,
-				(gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO,
-				node);
+		pages = kmalloc_node(array_size, nested_gfp, node);
 	}
 	area->pages = pages;
 	area->caller = caller;



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/