Slab allocators: Replace explicit zeroing with __GFP_ZERO

kmalloc_node() and kmem_cache_alloc_node() were not available in a zeroing
variant in the past.  But with __GFP_ZERO it is possible now to do zeroing
while allocating.

Use __GFP_ZERO to remove the explicit clearing of memory via memset whereever
we can.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 7 insertions, 11 deletions

diff --git a/mm/allocpercpu.c b/mm/allocpercpu.c
index b2486cf887a0..00b02623f008 100644
--- a/mm/allocpercpu.c
+++ b/mm/allocpercpu.c
@@ -53,12 +53,9 @@ void *percpu_populate(void *__pdata, size_t size, gfp_t gfp, int cpu)
         int node = cpu_to_node(cpu);
 
         BUG_ON(pdata->ptrs[cpu]);
-        if (node_online(node)) {
-                /* FIXME: kzalloc_node(size, gfp, node) */
-                pdata->ptrs[cpu] = kmalloc_node(size, gfp, node);
-                if (pdata->ptrs[cpu])
-                        memset(pdata->ptrs[cpu], 0, size);
-        } else
+        if (node_online(node))
+                pdata->ptrs[cpu] = kmalloc_node(size, gfp|__GFP_ZERO, node);
+        else
                 pdata->ptrs[cpu] = kzalloc(size, gfp);
         return pdata->ptrs[cpu];
 }
diff --git a/mm/mempool.c b/mm/mempool.c
index 3e8f1fed0e1f..02d5ec3feabc 100644
--- a/mm/mempool.c
+++ b/mm/mempool.c
@@ -62,10 +62,9 @@ mempool_t *mempool_create_node(int min_nr, mempool_alloc_t *alloc_fn,
                         mempool_free_t *free_fn, void *pool_data, int node_id)
 {
         mempool_t *pool;
-        pool = kmalloc_node(sizeof(*pool), GFP_KERNEL, node_id);
+        pool = kmalloc_node(sizeof(*pool), GFP_KERNEL | __GFP_ZERO, node_id);
         if (!pool)
                 return NULL;
-        memset(pool, 0, sizeof(*pool));
         pool->elements = kmalloc_node(min_nr * sizeof(void *),
                                         GFP_KERNEL, node_id);
         if (!pool->elements) {
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index ddf87145cc49..8e05a11155c9 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -432,11 +432,12 @@ void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
         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, PAGE_KERNEL, node);
+                pages = __vmalloc_node(array_size, gfp_mask | __GFP_ZERO,
+                                        PAGE_KERNEL, node);
                 area->flags |= VM_VPAGES;
         } else {
                 pages = kmalloc_node(array_size,
-                                (gfp_mask & GFP_LEVEL_MASK),
+                                (gfp_mask & GFP_LEVEL_MASK) | __GFP_ZERO,
                                 node);
         }
         area->pages = pages;
@@ -445,7 +446,6 @@ void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
                 kfree(area);
                 return NULL;
         }
-        memset(area->pages, 0, array_size);
 
         for (i = 0; i < area->nr_pages; i++) {
                 if (node < 0)