kernel_optimize_test/include/net/udp.h
subashab@codeaurora.org dddb64bcb3 net: Add sysctl to toggle early demux for tcp and udp
Certain system process significant unconnected UDP workload.
It would be preferrable to disable UDP early demux for those systems
and enable it for TCP only.

By disabling UDP demux, we see these slight gains on an ARM64 system-
782 -> 788Mbps unconnected single stream UDPv4
633 -> 654Mbps unconnected UDPv4 different sources

The performance impact can change based on CPU architecure and cache
sizes. There will not much difference seen if entire UDP hash table
is in cache.

Both sysctls are enabled by default to preserve existing behavior.

v1->v2: Change function pointer instead of adding conditional as
suggested by Stephen.

v2->v3: Read once in callers to avoid issues due to compiler
optimizations. Also update commit message with the tests.

v3->v4: Store and use read once result instead of querying pointer
again incorrectly.

v4->v5: Refactor to avoid errors due to compilation with IPV6={m,n}

Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Suggested-by: Eric Dumazet <edumazet@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Tom Herbert <tom@herbertland.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-24 13:17:07 -07:00

377 lines
11 KiB
C

/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* Definitions for the UDP module.
*
* Version: @(#)udp.h 1.0.2 05/07/93
*
* Authors: Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
*
* Fixes:
* Alan Cox : Turned on udp checksums. I don't want to
* chase 'memory corruption' bugs that aren't!
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _UDP_H
#define _UDP_H
#include <linux/list.h>
#include <linux/bug.h>
#include <net/inet_sock.h>
#include <net/sock.h>
#include <net/snmp.h>
#include <net/ip.h>
#include <linux/ipv6.h>
#include <linux/seq_file.h>
#include <linux/poll.h>
/**
* struct udp_skb_cb - UDP(-Lite) private variables
*
* @header: private variables used by IPv4/IPv6
* @cscov: checksum coverage length (UDP-Lite only)
* @partial_cov: if set indicates partial csum coverage
*/
struct udp_skb_cb {
union {
struct inet_skb_parm h4;
#if IS_ENABLED(CONFIG_IPV6)
struct inet6_skb_parm h6;
#endif
} header;
__u16 cscov;
__u8 partial_cov;
};
#define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb))
/**
* struct udp_hslot - UDP hash slot
*
* @head: head of list of sockets
* @count: number of sockets in 'head' list
* @lock: spinlock protecting changes to head/count
*/
struct udp_hslot {
struct hlist_head head;
int count;
spinlock_t lock;
} __attribute__((aligned(2 * sizeof(long))));
/**
* struct udp_table - UDP table
*
* @hash: hash table, sockets are hashed on (local port)
* @hash2: hash table, sockets are hashed on (local port, local address)
* @mask: number of slots in hash tables, minus 1
* @log: log2(number of slots in hash table)
*/
struct udp_table {
struct udp_hslot *hash;
struct udp_hslot *hash2;
unsigned int mask;
unsigned int log;
};
extern struct udp_table udp_table;
void udp_table_init(struct udp_table *, const char *);
static inline struct udp_hslot *udp_hashslot(struct udp_table *table,
struct net *net, unsigned int num)
{
return &table->hash[udp_hashfn(net, num, table->mask)];
}
/*
* For secondary hash, net_hash_mix() is performed before calling
* udp_hashslot2(), this explains difference with udp_hashslot()
*/
static inline struct udp_hslot *udp_hashslot2(struct udp_table *table,
unsigned int hash)
{
return &table->hash2[hash & table->mask];
}
extern struct proto udp_prot;
extern atomic_long_t udp_memory_allocated;
/* sysctl variables for udp */
extern long sysctl_udp_mem[3];
extern int sysctl_udp_rmem_min;
extern int sysctl_udp_wmem_min;
struct sk_buff;
/*
* Generic checksumming routines for UDP(-Lite) v4 and v6
*/
static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb)
{
return (UDP_SKB_CB(skb)->cscov == skb->len ?
__skb_checksum_complete(skb) :
__skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov));
}
static inline int udp_lib_checksum_complete(struct sk_buff *skb)
{
return !skb_csum_unnecessary(skb) &&
__udp_lib_checksum_complete(skb);
}
/**
* udp_csum_outgoing - compute UDPv4/v6 checksum over fragments
* @sk: socket we are writing to
* @skb: sk_buff containing the filled-in UDP header
* (checksum field must be zeroed out)
*/
static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb)
{
__wsum csum = csum_partial(skb_transport_header(skb),
sizeof(struct udphdr), 0);
skb_queue_walk(&sk->sk_write_queue, skb) {
csum = csum_add(csum, skb->csum);
}
return csum;
}
static inline __wsum udp_csum(struct sk_buff *skb)
{
__wsum csum = csum_partial(skb_transport_header(skb),
sizeof(struct udphdr), skb->csum);
for (skb = skb_shinfo(skb)->frag_list; skb; skb = skb->next) {
csum = csum_add(csum, skb->csum);
}
return csum;
}
static inline __sum16 udp_v4_check(int len, __be32 saddr,
__be32 daddr, __wsum base)
{
return csum_tcpudp_magic(saddr, daddr, len, IPPROTO_UDP, base);
}
void udp_set_csum(bool nocheck, struct sk_buff *skb,
__be32 saddr, __be32 daddr, int len);
static inline void udp_csum_pull_header(struct sk_buff *skb)
{
if (!skb->csum_valid && skb->ip_summed == CHECKSUM_NONE)
skb->csum = csum_partial(skb->data, sizeof(struct udphdr),
skb->csum);
skb_pull_rcsum(skb, sizeof(struct udphdr));
UDP_SKB_CB(skb)->cscov -= sizeof(struct udphdr);
}
typedef struct sock *(*udp_lookup_t)(struct sk_buff *skb, __be16 sport,
__be16 dport);
struct sk_buff **udp_gro_receive(struct sk_buff **head, struct sk_buff *skb,
struct udphdr *uh, udp_lookup_t lookup);
int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);
static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
{
struct udphdr *uh;
unsigned int hlen, off;
off = skb_gro_offset(skb);
hlen = off + sizeof(*uh);
uh = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, hlen))
uh = skb_gro_header_slow(skb, hlen, off);
return uh;
}
/* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
static inline int udp_lib_hash(struct sock *sk)
{
BUG();
return 0;
}
void udp_lib_unhash(struct sock *sk);
void udp_lib_rehash(struct sock *sk, u16 new_hash);
static inline void udp_lib_close(struct sock *sk, long timeout)
{
sk_common_release(sk);
}
int udp_lib_get_port(struct sock *sk, unsigned short snum,
unsigned int hash2_nulladdr);
u32 udp_flow_hashrnd(void);
static inline __be16 udp_flow_src_port(struct net *net, struct sk_buff *skb,
int min, int max, bool use_eth)
{
u32 hash;
if (min >= max) {
/* Use default range */
inet_get_local_port_range(net, &min, &max);
}
hash = skb_get_hash(skb);
if (unlikely(!hash)) {
if (use_eth) {
/* Can't find a normal hash, caller has indicated an
* Ethernet packet so use that to compute a hash.
*/
hash = jhash(skb->data, 2 * ETH_ALEN,
(__force u32) skb->protocol);
} else {
/* Can't derive any sort of hash for the packet, set
* to some consistent random value.
*/
hash = udp_flow_hashrnd();
}
}
/* Since this is being sent on the wire obfuscate hash a bit
* to minimize possbility that any useful information to an
* attacker is leaked. Only upper 16 bits are relevant in the
* computation for 16 bit port value.
*/
hash ^= hash << 16;
return htons((((u64) hash * (max - min)) >> 32) + min);
}
/* net/ipv4/udp.c */
void udp_destruct_sock(struct sock *sk);
void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len);
int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb);
void udp_skb_destructor(struct sock *sk, struct sk_buff *skb);
static inline struct sk_buff *
__skb_recv_udp(struct sock *sk, unsigned int flags, int noblock, int *peeked,
int *off, int *err)
{
return __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
udp_skb_destructor, peeked, off, err);
}
static inline struct sk_buff *skb_recv_udp(struct sock *sk, unsigned int flags,
int noblock, int *err)
{
int peeked, off = 0;
return __skb_recv_udp(sk, flags, noblock, &peeked, &off, err);
}
void udp_v4_early_demux(struct sk_buff *skb);
int udp_get_port(struct sock *sk, unsigned short snum,
int (*saddr_cmp)(const struct sock *,
const struct sock *));
void udp_err(struct sk_buff *, u32);
int udp_abort(struct sock *sk, int err);
int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len);
int udp_push_pending_frames(struct sock *sk);
void udp_flush_pending_frames(struct sock *sk);
void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst);
int udp_rcv(struct sk_buff *skb);
int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
int udp_init_sock(struct sock *sk);
int __udp_disconnect(struct sock *sk, int flags);
int udp_disconnect(struct sock *sk, int flags);
unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait);
struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb,
netdev_features_t features,
bool is_ipv6);
int udp_lib_getsockopt(struct sock *sk, int level, int optname,
char __user *optval, int __user *optlen);
int udp_lib_setsockopt(struct sock *sk, int level, int optname,
char __user *optval, unsigned int optlen,
int (*push_pending_frames)(struct sock *));
struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
__be32 daddr, __be16 dport, int dif);
struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
__be32 daddr, __be16 dport, int dif,
struct udp_table *tbl, struct sk_buff *skb);
struct sock *udp4_lib_lookup_skb(struct sk_buff *skb,
__be16 sport, __be16 dport);
struct sock *udp6_lib_lookup(struct net *net,
const struct in6_addr *saddr, __be16 sport,
const struct in6_addr *daddr, __be16 dport,
int dif);
struct sock *__udp6_lib_lookup(struct net *net,
const struct in6_addr *saddr, __be16 sport,
const struct in6_addr *daddr, __be16 dport,
int dif, struct udp_table *tbl,
struct sk_buff *skb);
struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
__be16 sport, __be16 dport);
/*
* SNMP statistics for UDP and UDP-Lite
*/
#define UDP_INC_STATS(net, field, is_udplite) do { \
if (is_udplite) SNMP_INC_STATS((net)->mib.udplite_statistics, field); \
else SNMP_INC_STATS((net)->mib.udp_statistics, field); } while(0)
#define __UDP_INC_STATS(net, field, is_udplite) do { \
if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_statistics, field); \
else __SNMP_INC_STATS((net)->mib.udp_statistics, field); } while(0)
#define __UDP6_INC_STATS(net, field, is_udplite) do { \
if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_stats_in6, field);\
else __SNMP_INC_STATS((net)->mib.udp_stats_in6, field); \
} while(0)
#define UDP6_INC_STATS(net, field, __lite) do { \
if (__lite) SNMP_INC_STATS((net)->mib.udplite_stats_in6, field); \
else SNMP_INC_STATS((net)->mib.udp_stats_in6, field); \
} while(0)
#if IS_ENABLED(CONFIG_IPV6)
#define __UDPX_INC_STATS(sk, field) \
do { \
if ((sk)->sk_family == AF_INET) \
__UDP_INC_STATS(sock_net(sk), field, 0); \
else \
__UDP6_INC_STATS(sock_net(sk), field, 0); \
} while (0)
#else
#define __UDPX_INC_STATS(sk, field) __UDP_INC_STATS(sock_net(sk), field, 0)
#endif
/* /proc */
int udp_seq_open(struct inode *inode, struct file *file);
struct udp_seq_afinfo {
char *name;
sa_family_t family;
struct udp_table *udp_table;
const struct file_operations *seq_fops;
struct seq_operations seq_ops;
};
struct udp_iter_state {
struct seq_net_private p;
sa_family_t family;
int bucket;
struct udp_table *udp_table;
};
#ifdef CONFIG_PROC_FS
int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo);
void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo);
int udp4_proc_init(void);
void udp4_proc_exit(void);
#endif
int udpv4_offload_init(void);
void udp_init(void);
void udp_encap_enable(void);
#if IS_ENABLED(CONFIG_IPV6)
void udpv6_encap_enable(void);
#endif
#endif /* _UDP_H */