[PATCH][net-next] skbuff: pass the result of data ksize to __build_skb_around
From: Li RongQing <hidden>
Date: 2021-09-22 06:18:34
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Avoid to call ksize again in __build_skb_around by passing the result of data ksize to __build_skb_around nginx stress test shows this change can reduce ksize cpu usage, and give a little performance boost Signed-off-by: Li RongQing <redacted> --- net/core/skbuff.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 9240af2..1e0a930 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c@@ -397,8 +397,9 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, { struct kmem_cache *cache; struct sk_buff *skb; - u8 *data; + unsigned int osize; bool pfmemalloc; + u8 *data; cache = (flags & SKB_ALLOC_FCLONE) ? skbuff_fclone_cache : skbuff_head_cache;
@@ -430,7 +431,8 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, * Put skb_shared_info exactly at the end of allocated zone, * to allow max possible filling before reallocation. */ - size = SKB_WITH_OVERHEAD(ksize(data)); + osize = ksize(data); + size = SKB_WITH_OVERHEAD(osize); prefetchw(data + size); /*
@@ -439,7 +441,7 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, * the tail pointer in struct sk_buff! */ memset(skb, 0, offsetof(struct sk_buff, tail)); - __build_skb_around(skb, data, 0); + __build_skb_around(skb, data, osize); skb->pfmemalloc = pfmemalloc; if (flags & SKB_ALLOC_FCLONE) {
--
1.7.1