Commit 115f1a5c authored by Eric Dumazet's avatar Eric Dumazet Committed by Jakub Kicinski
Browse files

net: add SKB_HEAD_ALIGN() helper 



We have many places using this expression:

 SKB_DATA_ALIGN(sizeof(struct skb_shared_info))

Use of SKB_HEAD_ALIGN() will allow to clean them.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: default avatarPaolo Abeni <pabeni@redhat.com>
Reviewed-by: default avatarAlexander Duyck <alexanderduyck@fb.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 61d731e6

include/linux/skbuff.h

+8 −0
Original line number Diff line number Diff line
@@ -255,6 +255,14 @@ 
#define SKB_DATA_ALIGN(X)	ALIGN(X, SMP_CACHE_BYTES)

#define SKB_WITH_OVERHEAD(X)	\

	((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))



/* For X bytes available in skb->head, what is the minimal

 * allocation needed, knowing struct skb_shared_info needs

 * to be aligned.

 */

#define SKB_HEAD_ALIGN(X) (SKB_DATA_ALIGN(X) + \

	SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))



#define SKB_MAX_ORDER(X, ORDER) \

	SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))

#define SKB_MAX_HEAD(X)		(SKB_MAX_ORDER((X), 0))

net/core/skbuff.c

+6 −12
Original line number Diff line number Diff line
@@ -558,8 +558,7 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, 
	 * aligned memory blocks, unless SLUB/SLAB debug is enabled.

	 * Both skb->head and skb_shared_info are cache line aligned.

	 */

	size = SKB_DATA_ALIGN(size);

	size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

	size = SKB_HEAD_ALIGN(size);

	osize = kmalloc_size_roundup(size);

	data = kmalloc_reserve(osize, gfp_mask, node, &pfmemalloc);

	if (unlikely(!data))
@@ -632,8 +631,7 @@ struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int len, 
		goto skb_success;

	}



	len += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

	len = SKB_DATA_ALIGN(len);

	len = SKB_HEAD_ALIGN(len);



	if (sk_memalloc_socks())

		gfp_mask |= __GFP_MEMALLOC;
@@ -732,8 +730,7 @@ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len, 
		data = page_frag_alloc_1k(&nc->page_small, gfp_mask);

		pfmemalloc = NAPI_SMALL_PAGE_PFMEMALLOC(nc->page_small);

	} else {

		len += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

		len = SKB_DATA_ALIGN(len);

		len = SKB_HEAD_ALIGN(len);



		data = page_frag_alloc(&nc->page, len, gfp_mask);

		pfmemalloc = nc->page.pfmemalloc;
@@ -1938,8 +1935,7 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, 
	if (skb_pfmemalloc(skb))

		gfp_mask |= __GFP_MEMALLOC;



	size = SKB_DATA_ALIGN(size);

	size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

	size = SKB_HEAD_ALIGN(size);

	size = kmalloc_size_roundup(size);

	data = kmalloc_reserve(size, gfp_mask, NUMA_NO_NODE, NULL);

	if (!data)
@@ -6289,8 +6285,7 @@ static int pskb_carve_inside_header(struct sk_buff *skb, const u32 off, 
	if (skb_pfmemalloc(skb))

		gfp_mask |= __GFP_MEMALLOC;



	size = SKB_DATA_ALIGN(size);

	size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

	size = SKB_HEAD_ALIGN(size);

	size = kmalloc_size_roundup(size);

	data = kmalloc_reserve(size, gfp_mask, NUMA_NO_NODE, NULL);

	if (!data)
@@ -6408,8 +6403,7 @@ static int pskb_carve_inside_nonlinear(struct sk_buff *skb, const u32 off, 
	if (skb_pfmemalloc(skb))

		gfp_mask |= __GFP_MEMALLOC;



	size = SKB_DATA_ALIGN(size);

	size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

	size = SKB_HEAD_ALIGN(size);

	size = kmalloc_size_roundup(size);

	data = kmalloc_reserve(size, gfp_mask, NUMA_NO_NODE, NULL);

	if (!data)