From 9d4dde5215779f4099730194ad30624fdba3d8b2 Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Thu, 22 Dec 2011 23:39:14 +0000 Subject: [PATCH] net: only use a single page of slop in MAX_SKB_FRAGS In order to accommodate a 64K buffer we need 64K/PAGE_SIZE plus one more page in order to allow for a buffer which does not start on a page boundary. Signed-off-by: Ian Campbell Signed-off-by: David S. Miller --- include/linux/skbuff.h | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 12e6fed..f47f0c3 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -128,13 +128,17 @@ struct sk_buff_head { struct sk_buff; -/* To allow 64K frame to be packed as single skb without frag_list. Since - * GRO uses frags we allocate at least 16 regardless of page size. +/* To allow 64K frame to be packed as single skb without frag_list we + * require 64K/PAGE_SIZE pages plus 1 additional page to allow for + * buffers which do not start on a page boundary. + * + * Since GRO uses frags we allocate at least 16 regardless of page + * size. */ -#if (65536/PAGE_SIZE + 2) < 16 +#if (65536/PAGE_SIZE + 1) < 16 #define MAX_SKB_FRAGS 16UL #else -#define MAX_SKB_FRAGS (65536/PAGE_SIZE + 2) +#define MAX_SKB_FRAGS (65536/PAGE_SIZE + 1) #endif typedef struct skb_frag_struct skb_frag_t; -- 2.7.4