From 0200f240cf9712f1b3d03597bd4282380f9771ce Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 12 Jul 2011 15:38:34 +0200 Subject: [PATCH 236/323] net: Use skbufhead with raw lock Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patches-5.10.215-rt107.tar.xz Use the rps lock as rawlock so we can keep irq-off regions. It looks low latency. However we can't kfree() from this context therefore we defer this to the softirq and use the tofree_queue list for it (similar to process_queue). Signed-off-by: Thomas Gleixner --- include/linux/skbuff.h | 7 +++++++ net/core/dev.c | 6 +++--- 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index a210f19958621..af89bd5e7d568 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -296,6 +296,7 @@ struct sk_buff_head { __u32 qlen; spinlock_t lock; + raw_spinlock_t raw_lock; }; struct sk_buff; @@ -1892,6 +1893,12 @@ static inline void skb_queue_head_init(struct sk_buff_head *list) __skb_queue_head_init(list); } +static inline void skb_queue_head_init_raw(struct sk_buff_head *list) +{ + raw_spin_lock_init(&list->raw_lock); + __skb_queue_head_init(list); +} + static inline void skb_queue_head_init_class(struct sk_buff_head *list, struct lock_class_key *class) { diff --git a/net/core/dev.c b/net/core/dev.c index 7d95a0251617e..48fcb050b5a7b 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -221,14 +221,14 @@ static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) static inline void rps_lock(struct softnet_data *sd) { #ifdef CONFIG_RPS - spin_lock(&sd->input_pkt_queue.lock); + raw_spin_lock(&sd->input_pkt_queue.raw_lock); #endif } static inline void rps_unlock(struct softnet_data *sd) { #ifdef CONFIG_RPS - spin_unlock(&sd->input_pkt_queue.lock); + raw_spin_unlock(&sd->input_pkt_queue.raw_lock); #endif } @@ -11304,7 +11304,7 @@ static int __init net_dev_init(void) INIT_WORK(flush, flush_backlog); - skb_queue_head_init(&sd->input_pkt_queue); + skb_queue_head_init_raw(&sd->input_pkt_queue); skb_queue_head_init(&sd->process_queue); #ifdef CONFIG_XFRM_OFFLOAD skb_queue_head_init(&sd->xfrm_backlog); -- 2.44.0