kernel: relay: use __GFP_ZERO in relay_alloc_buf

Passing the __GFP_ZERO flag to alloc_page should result in less overhead
th= an using memset()

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Elijah Wright <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: elijah-wright

kernel/relay.c

@@ -118,7 +118,7 @@ static void *relay_alloc_buf(struct rchan_buf *buf, size_t *size)
 		return NULL;
 
 	for (i = 0; i < n_pages; i++) {
-		buf->page_array[i] = alloc_page(GFP_KERNEL);
+		buf->page_array[i] = alloc_page(GFP_KERNEL | __GFP_ZERO);
 		if (unlikely(!buf->page_array[i]))
 			goto depopulate;
 		set_page_private(buf->page_array[i], (unsigned long)buf);
@@ -127,7 +127,6 @@ static void *relay_alloc_buf(struct rchan_buf *buf, size_t *size)
 	if (!mem)
 		goto depopulate;
 
-	memset(mem, 0, *size);
 	buf->page_count = n_pages;
 	return mem;