2 * net busy poll support
3 * Copyright(c) 2013 Intel Corporation.
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18 * Author: Eliezer Tamir
20 * Contact Information:
21 * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
24 #ifndef _LINUX_NET_BUSY_POLL_H
25 #define _LINUX_NET_BUSY_POLL_H
27 #include <linux/netdevice.h>
28 #include <linux/sched/clock.h>
31 #ifdef CONFIG_NET_RX_BUSY_POLL
34 extern unsigned int sysctl_net_busy_read __read_mostly;
35 extern unsigned int sysctl_net_busy_poll __read_mostly;
37 static inline bool net_busy_loop_on(void)
39 return sysctl_net_busy_poll;
42 static inline u64 busy_loop_us_clock(void)
44 return local_clock() >> 10;
47 static inline unsigned long sk_busy_loop_end_time(struct sock *sk)
49 return busy_loop_us_clock() + ACCESS_ONCE(sk->sk_ll_usec);
52 /* in poll/select we use the global sysctl_net_ll_poll value */
53 static inline unsigned long busy_loop_end_time(void)
55 return busy_loop_us_clock() + ACCESS_ONCE(sysctl_net_busy_poll);
58 static inline bool sk_can_busy_loop(const struct sock *sk)
60 return sk->sk_ll_usec && sk->sk_napi_id && !signal_pending(current);
64 static inline bool busy_loop_timeout(unsigned long end_time)
66 unsigned long now = busy_loop_us_clock();
68 return time_after(now, end_time);
71 bool sk_busy_loop(struct sock *sk, int nonblock);
73 /* used in the NIC receive handler to mark the skb */
74 static inline void skb_mark_napi_id(struct sk_buff *skb,
75 struct napi_struct *napi)
77 skb->napi_id = napi->napi_id;
81 #else /* CONFIG_NET_RX_BUSY_POLL */
82 static inline unsigned long net_busy_loop_on(void)
87 static inline unsigned long busy_loop_end_time(void)
92 static inline bool sk_can_busy_loop(struct sock *sk)
97 static inline void skb_mark_napi_id(struct sk_buff *skb,
98 struct napi_struct *napi)
102 static inline bool busy_loop_timeout(unsigned long end_time)
107 static inline bool sk_busy_loop(struct sock *sk, int nonblock)
112 #endif /* CONFIG_NET_RX_BUSY_POLL */
114 /* used in the protocol hanlder to propagate the napi_id to the socket */
115 static inline void sk_mark_napi_id(struct sock *sk, const struct sk_buff *skb)
117 #ifdef CONFIG_NET_RX_BUSY_POLL
118 sk->sk_napi_id = skb->napi_id;
122 /* variant used for unconnected sockets */
123 static inline void sk_mark_napi_id_once(struct sock *sk,
124 const struct sk_buff *skb)
126 #ifdef CONFIG_NET_RX_BUSY_POLL
128 sk->sk_napi_id = skb->napi_id;
132 #endif /* _LINUX_NET_BUSY_POLL_H */