kernel_optimize_test/net/openvswitch/flow.h
Tonghao Zhang c4b2bf6b4a openvswitch: Optimize operations for OvS flow_stats.
When calling the flow_free() to free the flow, we call many times
(cpu_possible_mask, eg. 128 as default) cpumask_next(). That will
take up our CPU usage if we call the flow_free() frequently.
When we put all packets to userspace via upcall, and OvS will send
them back via netlink to ovs_packet_cmd_execute(will call flow_free).

The test topo is shown as below. VM01 sends TCP packets to VM02,
and OvS forward packtets. When testing, we use perf to report the
system performance.

VM01 --- OvS-VM --- VM02

Without this patch, perf-top show as below: The flow_free() is
3.02% CPU usage.

	4.23%  [kernel]            [k] _raw_spin_unlock_irqrestore
	3.62%  [kernel]            [k] __do_softirq
	3.16%  [kernel]            [k] __memcpy
	3.02%  [kernel]            [k] flow_free
	2.42%  libc-2.17.so        [.] __memcpy_ssse3_back
	2.18%  [kernel]            [k] copy_user_generic_unrolled
	2.17%  [kernel]            [k] find_next_bit

When applied this patch, perf-top show as below: Not shown on
the list anymore.

	4.11%  [kernel]            [k] _raw_spin_unlock_irqrestore
	3.79%  [kernel]            [k] __do_softirq
	3.46%  [kernel]            [k] __memcpy
	2.73%  libc-2.17.so        [.] __memcpy_ssse3_back
	2.25%  [kernel]            [k] copy_user_generic_unrolled
	1.89%  libc-2.17.so        [.] _int_malloc
	1.53%  ovs-vswitchd        [.] xlate_actions

With this patch, the TCP throughput(we dont use Megaflow Cache
+ Microflow Cache) between VMs is 1.18Gbs/sec up to 1.30Gbs/sec
(maybe ~10% performance imporve).

This patch adds cpumask struct, the cpu_used_mask stores the cpu_id
that the flow used. And we only check the flow_stats on the cpu we
used, and it is unncessary to check all possible cpu when getting,
cleaning, and updating the flow_stats. Adding the cpu_used_mask to
sw_flow struct does’t increase the cacheline number.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-19 13:49:39 -07:00

289 lines
8.2 KiB
C

/*
* Copyright (c) 2007-2017 Nicira, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA
*/
#ifndef FLOW_H
#define FLOW_H 1
#include <linux/cache.h>
#include <linux/kernel.h>
#include <linux/netlink.h>
#include <linux/openvswitch.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/rcupdate.h>
#include <linux/if_ether.h>
#include <linux/in6.h>
#include <linux/jiffies.h>
#include <linux/time.h>
#include <linux/flex_array.h>
#include <linux/cpumask.h>
#include <net/inet_ecn.h>
#include <net/ip_tunnels.h>
#include <net/dst_metadata.h>
struct sk_buff;
enum sw_flow_mac_proto {
MAC_PROTO_NONE = 0,
MAC_PROTO_ETHERNET,
};
#define SW_FLOW_KEY_INVALID 0x80
/* Store options at the end of the array if they are less than the
* maximum size. This allows us to get the benefits of variable length
* matching for small options.
*/
#define TUN_METADATA_OFFSET(opt_len) \
(FIELD_SIZEOF(struct sw_flow_key, tun_opts) - opt_len)
#define TUN_METADATA_OPTS(flow_key, opt_len) \
((void *)((flow_key)->tun_opts + TUN_METADATA_OFFSET(opt_len)))
struct ovs_tunnel_info {
struct metadata_dst *tun_dst;
};
struct vlan_head {
__be16 tpid; /* Vlan type. Generally 802.1q or 802.1ad.*/
__be16 tci; /* 0 if no VLAN, VLAN_TAG_PRESENT set otherwise. */
};
#define OVS_SW_FLOW_KEY_METADATA_SIZE \
(offsetof(struct sw_flow_key, recirc_id) + \
FIELD_SIZEOF(struct sw_flow_key, recirc_id))
struct sw_flow_key {
u8 tun_opts[IP_TUNNEL_OPTS_MAX];
u8 tun_opts_len;
struct ip_tunnel_key tun_key; /* Encapsulating tunnel key. */
struct {
u32 priority; /* Packet QoS priority. */
u32 skb_mark; /* SKB mark. */
u16 in_port; /* Input switch port (or DP_MAX_PORTS). */
} __packed phy; /* Safe when right after 'tun_key'. */
u8 mac_proto; /* MAC layer protocol (e.g. Ethernet). */
u8 tun_proto; /* Protocol of encapsulating tunnel. */
u32 ovs_flow_hash; /* Datapath computed hash value. */
u32 recirc_id; /* Recirculation ID. */
struct {
u8 src[ETH_ALEN]; /* Ethernet source address. */
u8 dst[ETH_ALEN]; /* Ethernet destination address. */
struct vlan_head vlan;
struct vlan_head cvlan;
__be16 type; /* Ethernet frame type. */
} eth;
/* Filling a hole of two bytes. */
u8 ct_state;
u8 ct_orig_proto; /* CT original direction tuple IP
* protocol.
*/
union {
struct {
__be32 top_lse; /* top label stack entry */
} mpls;
struct {
u8 proto; /* IP protocol or lower 8 bits of ARP opcode. */
u8 tos; /* IP ToS. */
u8 ttl; /* IP TTL/hop limit. */
u8 frag; /* One of OVS_FRAG_TYPE_*. */
} ip;
};
u16 ct_zone; /* Conntrack zone. */
struct {
__be16 src; /* TCP/UDP/SCTP source port. */
__be16 dst; /* TCP/UDP/SCTP destination port. */
__be16 flags; /* TCP flags. */
} tp;
union {
struct {
struct {
__be32 src; /* IP source address. */
__be32 dst; /* IP destination address. */
} addr;
union {
struct {
__be32 src;
__be32 dst;
} ct_orig; /* Conntrack original direction fields. */
struct {
u8 sha[ETH_ALEN]; /* ARP source hardware address. */
u8 tha[ETH_ALEN]; /* ARP target hardware address. */
} arp;
};
} ipv4;
struct {
struct {
struct in6_addr src; /* IPv6 source address. */
struct in6_addr dst; /* IPv6 destination address. */
} addr;
__be32 label; /* IPv6 flow label. */
union {
struct {
struct in6_addr src;
struct in6_addr dst;
} ct_orig; /* Conntrack original direction fields. */
struct {
struct in6_addr target; /* ND target address. */
u8 sll[ETH_ALEN]; /* ND source link layer address. */
u8 tll[ETH_ALEN]; /* ND target link layer address. */
} nd;
};
} ipv6;
};
struct {
/* Connection tracking fields not packed above. */
struct {
__be16 src; /* CT orig tuple tp src port. */
__be16 dst; /* CT orig tuple tp dst port. */
} orig_tp;
u32 mark;
struct ovs_key_ct_labels labels;
} ct;
} __aligned(BITS_PER_LONG/8); /* Ensure that we can do comparisons as longs. */
static inline bool sw_flow_key_is_nd(const struct sw_flow_key *key)
{
return key->eth.type == htons(ETH_P_IPV6) &&
key->ip.proto == NEXTHDR_ICMP &&
key->tp.dst == 0 &&
(key->tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
key->tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT));
}
struct sw_flow_key_range {
unsigned short int start;
unsigned short int end;
};
struct sw_flow_mask {
int ref_count;
struct rcu_head rcu;
struct list_head list;
struct sw_flow_key_range range;
struct sw_flow_key key;
};
struct sw_flow_match {
struct sw_flow_key *key;
struct sw_flow_key_range range;
struct sw_flow_mask *mask;
};
#define MAX_UFID_LENGTH 16 /* 128 bits */
struct sw_flow_id {
u32 ufid_len;
union {
u32 ufid[MAX_UFID_LENGTH / 4];
struct sw_flow_key *unmasked_key;
};
};
struct sw_flow_actions {
struct rcu_head rcu;
size_t orig_len; /* From flow_cmd_new netlink actions size */
u32 actions_len;
struct nlattr actions[];
};
struct flow_stats {
u64 packet_count; /* Number of packets matched. */
u64 byte_count; /* Number of bytes matched. */
unsigned long used; /* Last used time (in jiffies). */
spinlock_t lock; /* Lock for atomic stats update. */
__be16 tcp_flags; /* Union of seen TCP flags. */
};
struct sw_flow {
struct rcu_head rcu;
struct {
struct hlist_node node[2];
u32 hash;
} flow_table, ufid_table;
int stats_last_writer; /* CPU id of the last writer on
* 'stats[0]'.
*/
struct sw_flow_key key;
struct sw_flow_id id;
struct cpumask cpu_used_mask;
struct sw_flow_mask *mask;
struct sw_flow_actions __rcu *sf_acts;
struct flow_stats __rcu *stats[]; /* One for each CPU. First one
* is allocated at flow creation time,
* the rest are allocated on demand
* while holding the 'stats[0].lock'.
*/
};
struct arp_eth_header {
__be16 ar_hrd; /* format of hardware address */
__be16 ar_pro; /* format of protocol address */
unsigned char ar_hln; /* length of hardware address */
unsigned char ar_pln; /* length of protocol address */
__be16 ar_op; /* ARP opcode (command) */
/* Ethernet+IPv4 specific members. */
unsigned char ar_sha[ETH_ALEN]; /* sender hardware address */
unsigned char ar_sip[4]; /* sender IP address */
unsigned char ar_tha[ETH_ALEN]; /* target hardware address */
unsigned char ar_tip[4]; /* target IP address */
} __packed;
static inline u8 ovs_key_mac_proto(const struct sw_flow_key *key)
{
return key->mac_proto & ~SW_FLOW_KEY_INVALID;
}
static inline u16 __ovs_mac_header_len(u8 mac_proto)
{
return mac_proto == MAC_PROTO_ETHERNET ? ETH_HLEN : 0;
}
static inline u16 ovs_mac_header_len(const struct sw_flow_key *key)
{
return __ovs_mac_header_len(ovs_key_mac_proto(key));
}
static inline bool ovs_identifier_is_ufid(const struct sw_flow_id *sfid)
{
return sfid->ufid_len;
}
static inline bool ovs_identifier_is_key(const struct sw_flow_id *sfid)
{
return !ovs_identifier_is_ufid(sfid);
}
void ovs_flow_stats_update(struct sw_flow *, __be16 tcp_flags,
const struct sk_buff *);
void ovs_flow_stats_get(const struct sw_flow *, struct ovs_flow_stats *,
unsigned long *used, __be16 *tcp_flags);
void ovs_flow_stats_clear(struct sw_flow *);
u64 ovs_flow_used_time(unsigned long flow_jiffies);
int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key);
int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
struct sk_buff *skb,
struct sw_flow_key *key);
/* Extract key from packet coming from userspace. */
int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
struct sk_buff *skb,
struct sw_flow_key *key, bool log);
#endif /* flow.h */