From c11171a413385c1a72291cdb4a7435cb189762ab Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Tue, 29 Sep 2020 22:25:12 +0200 Subject: [PATCH] net: Add netif_rx_any_context() Quite some drivers make conditional decisions based on in_interrupt() to invoke either netif_rx() or netif_rx_ni(). Conditionals based on in_interrupt() or other variants of preempt count checks in drivers should not exist for various reasons and Linus clearly requested to either split the code pathes or pass an argument to the common functions which provides the context. This is obviously the correct solution, but for some of the affected drivers this needs a major rewrite due to their convoluted structure. As in_interrupt() usage in drivers needs to be phased out, provide netif_rx_any_context() as a stop gap for these drivers. This confines the in_interrupt() conditional to core code which in turn allows to remove the access to this check for driver code and provides one central place to do further modifications once the driver maze is cleaned up. Suggested-by: Thomas Gleixner Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Signed-off-by: David S. Miller --- include/linux/netdevice.h | 1 + net/core/dev.c | 15 +++++++++++++++ 2 files changed, 16 insertions(+) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index a431c3229cbf..28cfa53daf72 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3785,6 +3785,7 @@ void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog); int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb); int netif_rx(struct sk_buff *skb); int netif_rx_ni(struct sk_buff *skb); +int netif_rx_any_context(struct sk_buff *skb); int netif_receive_skb(struct sk_buff *skb); int netif_receive_skb_core(struct sk_buff *skb); void netif_receive_skb_list(struct list_head *head); diff --git a/net/core/dev.c b/net/core/dev.c index 873b50ac9668..9d55bf5d1a65 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4841,6 +4841,21 @@ int netif_rx_ni(struct sk_buff *skb) } EXPORT_SYMBOL(netif_rx_ni); +int netif_rx_any_context(struct sk_buff *skb) +{ + /* + * If invoked from contexts which do not invoke bottom half + * processing either at return from interrupt or when softrqs are + * reenabled, use netif_rx_ni() which invokes bottomhalf processing + * directly. + */ + if (in_interrupt()) + return netif_rx(skb); + else + return netif_rx_ni(skb); +} +EXPORT_SYMBOL(netif_rx_any_context); + static __latent_entropy void net_tx_action(struct softirq_action *h) { struct softnet_data *sd = this_cpu_ptr(&softnet_data);