 68835aba4d
			
		
	
	
	68835aba4d
	
	
	
		
			
			Followup of commit b178bb3dfc (net: reorder struct sock fields)
Optimize INET input path a bit further, by :
1) moving sk_refcnt close to sk_lock.
This reduces number of dirtied cache lines by one on 64bit arches (and
64 bytes cache line size).
2) moving inet_daddr & inet_rcv_saddr at the beginning of sk
(same cache line than hash / family / bound_dev_if / nulls_node)
This reduces number of accessed cache lines in lookups by one, and dont
increase size of inet and timewait socks.
inet and tw sockets now share same place-holder for these fields.
Before patch :
offsetof(struct sock, sk_refcnt) = 0x10
offsetof(struct sock, sk_lock) = 0x40
offsetof(struct sock, sk_receive_queue) = 0x60
offsetof(struct inet_sock, inet_daddr) = 0x270
offsetof(struct inet_sock, inet_rcv_saddr) = 0x274
After patch :
offsetof(struct sock, sk_refcnt) = 0x44
offsetof(struct sock, sk_lock) = 0x48
offsetof(struct sock, sk_receive_queue) = 0x68
offsetof(struct inet_sock, inet_daddr) = 0x0
offsetof(struct inet_sock, inet_rcv_saddr) = 0x4
compute_score() (udp or tcp) now use a single cache line per ignored
item, instead of two.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
		
	
			
		
			
				
	
	
		
			236 lines
		
	
	
	
		
			6.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			236 lines
		
	
	
	
		
			6.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * INET		An implementation of the TCP/IP protocol suite for the LINUX
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|  *		operating system.  INET is implemented using the  BSD Socket
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|  *		interface as the means of communication with the user level.
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|  *
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|  *		Definitions for a generic INET TIMEWAIT sock
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|  *
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|  *		From code originally in net/tcp.h
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|  *
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|  *		This program is free software; you can redistribute it and/or
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|  *		modify it under the terms of the GNU General Public License
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|  *		as published by the Free Software Foundation; either version
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|  *		2 of the License, or (at your option) any later version.
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|  */
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| #ifndef _INET_TIMEWAIT_SOCK_
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| #define _INET_TIMEWAIT_SOCK_
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| 
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| 
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| #include <linux/kmemcheck.h>
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| #include <linux/list.h>
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| #include <linux/module.h>
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| #include <linux/timer.h>
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| #include <linux/types.h>
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| #include <linux/workqueue.h>
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| 
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| #include <net/inet_sock.h>
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| #include <net/sock.h>
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| #include <net/tcp_states.h>
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| #include <net/timewait_sock.h>
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| 
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| #include <asm/atomic.h>
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| 
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| struct inet_hashinfo;
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| 
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| #define INET_TWDR_RECYCLE_SLOTS_LOG	5
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| #define INET_TWDR_RECYCLE_SLOTS		(1 << INET_TWDR_RECYCLE_SLOTS_LOG)
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| 
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| /*
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|  * If time > 4sec, it is "slow" path, no recycling is required,
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|  * so that we select tick to get range about 4 seconds.
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|  */
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| #if HZ <= 16 || HZ > 4096
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| # error Unsupported: HZ <= 16 or HZ > 4096
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| #elif HZ <= 32
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| # define INET_TWDR_RECYCLE_TICK (5 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
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| #elif HZ <= 64
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| # define INET_TWDR_RECYCLE_TICK (6 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
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| #elif HZ <= 128
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| # define INET_TWDR_RECYCLE_TICK (7 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
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| #elif HZ <= 256
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| # define INET_TWDR_RECYCLE_TICK (8 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
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| #elif HZ <= 512
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| # define INET_TWDR_RECYCLE_TICK (9 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
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| #elif HZ <= 1024
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| # define INET_TWDR_RECYCLE_TICK (10 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
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| #elif HZ <= 2048
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| # define INET_TWDR_RECYCLE_TICK (11 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
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| #else
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| # define INET_TWDR_RECYCLE_TICK (12 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
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| #endif
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| 
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| /* TIME_WAIT reaping mechanism. */
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| #define INET_TWDR_TWKILL_SLOTS	8 /* Please keep this a power of 2. */
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| 
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| #define INET_TWDR_TWKILL_QUOTA 100
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| 
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| struct inet_timewait_death_row {
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| 	/* Short-time timewait calendar */
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| 	int			twcal_hand;
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| 	unsigned long		twcal_jiffie;
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| 	struct timer_list	twcal_timer;
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| 	struct hlist_head	twcal_row[INET_TWDR_RECYCLE_SLOTS];
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| 
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| 	spinlock_t		death_lock;
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| 	int			tw_count;
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| 	int			period;
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| 	u32			thread_slots;
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| 	struct work_struct	twkill_work;
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| 	struct timer_list	tw_timer;
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| 	int			slot;
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| 	struct hlist_head	cells[INET_TWDR_TWKILL_SLOTS];
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| 	struct inet_hashinfo 	*hashinfo;
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| 	int			sysctl_tw_recycle;
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| 	int			sysctl_max_tw_buckets;
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| };
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| 
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| extern void inet_twdr_hangman(unsigned long data);
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| extern void inet_twdr_twkill_work(struct work_struct *work);
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| extern void inet_twdr_twcal_tick(unsigned long data);
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| 
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| struct inet_bind_bucket;
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| 
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| /*
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|  * This is a TIME_WAIT sock. It works around the memory consumption
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|  * problems of sockets in such a state on heavily loaded servers, but
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|  * without violating the protocol specification.
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|  */
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| struct inet_timewait_sock {
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| 	/*
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| 	 * Now struct sock also uses sock_common, so please just
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| 	 * don't add nothing before this first member (__tw_common) --acme
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| 	 */
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| 	struct sock_common	__tw_common;
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| #define tw_family		__tw_common.skc_family
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| #define tw_state		__tw_common.skc_state
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| #define tw_reuse		__tw_common.skc_reuse
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| #define tw_bound_dev_if		__tw_common.skc_bound_dev_if
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| #define tw_node			__tw_common.skc_nulls_node
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| #define tw_bind_node		__tw_common.skc_bind_node
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| #define tw_refcnt		__tw_common.skc_refcnt
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| #define tw_hash			__tw_common.skc_hash
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| #define tw_prot			__tw_common.skc_prot
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| #define tw_net			__tw_common.skc_net
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| #define tw_daddr        	__tw_common.skc_daddr
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| #define tw_rcv_saddr    	__tw_common.skc_rcv_saddr
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| 	int			tw_timeout;
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| 	volatile unsigned char	tw_substate;
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| 	unsigned char		tw_rcv_wscale;
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| 
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| 	/* Socket demultiplex comparisons on incoming packets. */
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| 	/* these three are in inet_sock */
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| 	__be16			tw_sport;
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| 	__be16			tw_dport;
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| 	__u16			tw_num;
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| 	kmemcheck_bitfield_begin(flags);
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| 	/* And these are ours. */
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| 	unsigned int		tw_ipv6only     : 1,
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| 				tw_transparent  : 1,
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| 				tw_pad		: 14,	/* 14 bits hole */
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| 				tw_ipv6_offset  : 16;
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| 	kmemcheck_bitfield_end(flags);
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| 	unsigned long		tw_ttd;
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| 	struct inet_bind_bucket	*tw_tb;
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| 	struct hlist_node	tw_death_node;
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| };
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| 
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| static inline void inet_twsk_add_node_rcu(struct inet_timewait_sock *tw,
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| 				      struct hlist_nulls_head *list)
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| {
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| 	hlist_nulls_add_head_rcu(&tw->tw_node, list);
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| }
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| 
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| static inline void inet_twsk_add_bind_node(struct inet_timewait_sock *tw,
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| 					   struct hlist_head *list)
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| {
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| 	hlist_add_head(&tw->tw_bind_node, list);
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| }
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| 
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| static inline int inet_twsk_dead_hashed(const struct inet_timewait_sock *tw)
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| {
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| 	return !hlist_unhashed(&tw->tw_death_node);
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| }
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| 
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| static inline void inet_twsk_dead_node_init(struct inet_timewait_sock *tw)
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| {
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| 	tw->tw_death_node.pprev = NULL;
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| }
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| 
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| static inline void __inet_twsk_del_dead_node(struct inet_timewait_sock *tw)
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| {
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| 	__hlist_del(&tw->tw_death_node);
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| 	inet_twsk_dead_node_init(tw);
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| }
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| 
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| static inline int inet_twsk_del_dead_node(struct inet_timewait_sock *tw)
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| {
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| 	if (inet_twsk_dead_hashed(tw)) {
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| 		__inet_twsk_del_dead_node(tw);
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| 		return 1;
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| 	}
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| 	return 0;
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| }
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| 
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| #define inet_twsk_for_each(tw, node, head) \
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| 	hlist_nulls_for_each_entry(tw, node, head, tw_node)
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| 
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| #define inet_twsk_for_each_inmate(tw, node, jail) \
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| 	hlist_for_each_entry(tw, node, jail, tw_death_node)
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| 
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| #define inet_twsk_for_each_inmate_safe(tw, node, safe, jail) \
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| 	hlist_for_each_entry_safe(tw, node, safe, jail, tw_death_node)
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| 
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| static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
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| {
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| 	return (struct inet_timewait_sock *)sk;
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| }
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| 
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| static inline __be32 sk_rcv_saddr(const struct sock *sk)
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| {
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| /* both inet_sk() and inet_twsk() store rcv_saddr in skc_rcv_saddr */
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| 	return sk->__sk_common.skc_rcv_saddr;
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| }
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| 
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| extern void inet_twsk_put(struct inet_timewait_sock *tw);
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| 
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| extern int inet_twsk_unhash(struct inet_timewait_sock *tw);
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| 
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| extern int inet_twsk_bind_unhash(struct inet_timewait_sock *tw,
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| 				 struct inet_hashinfo *hashinfo);
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| 
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| extern struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
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| 						  const int state);
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| 
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| extern void __inet_twsk_hashdance(struct inet_timewait_sock *tw,
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| 				  struct sock *sk,
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| 				  struct inet_hashinfo *hashinfo);
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| 
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| extern void inet_twsk_schedule(struct inet_timewait_sock *tw,
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| 			       struct inet_timewait_death_row *twdr,
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| 			       const int timeo, const int timewait_len);
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| extern void inet_twsk_deschedule(struct inet_timewait_sock *tw,
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| 				 struct inet_timewait_death_row *twdr);
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| 
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| extern void inet_twsk_purge(struct inet_hashinfo *hashinfo,
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| 			    struct inet_timewait_death_row *twdr, int family);
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| 
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| static inline
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| struct net *twsk_net(const struct inet_timewait_sock *twsk)
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| {
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| #ifdef CONFIG_NET_NS
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| 	return rcu_dereference_raw(twsk->tw_net); /* protected by locking, */
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| 						  /* reference counting, */
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| 						  /* initialization, or RCU. */
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| #else
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| 	return &init_net;
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| #endif
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| }
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| 
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| static inline
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| void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
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| {
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| #ifdef CONFIG_NET_NS
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| 	rcu_assign_pointer(twsk->tw_net, net);
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| #endif
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| }
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| #endif	/* _INET_TIMEWAIT_SOCK_ */
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