From: Eric Dumazet edumazet@google.com
commit 115f1a5c42bdad9a9ea356fc0b4a39ec7537947f upstream.
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: Eric Dumazet edumazet@google.com Acked-by: Soheil Hassas Yeganeh soheil@google.com Acked-by: Paolo Abeni pabeni@redhat.com Reviewed-by: Alexander Duyck alexanderduyck@fb.com Signed-off-by: Jakub Kicinski kuba@kernel.org [Ajay: Regenerated the patch for v6.1.y] Signed-off-by: Ajay Kaher akaher@vmware.com --- include/linux/skbuff.h | 8 ++++++++ net/core/skbuff.c | 18 ++++++------------ 2 files changed, 14 insertions(+), 12 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index cc5ed2c..2feee14 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -261,6 +261,14 @@ #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)) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 24bf4aa..4aea8f5 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -504,8 +504,7 @@ 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)) @@ -578,8 +577,7 @@ 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; @@ -678,8 +676,7 @@ 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; @@ -1837,8 +1834,7 @@ 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) @@ -6204,8 +6200,7 @@ 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) @@ -6323,8 +6318,7 @@ 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)