From e298e505700604c97e6a9edb21cebb080bdb91f6 Mon Sep 17 00:00:00 2001 From: Pravin B Shelar Date: Tue, 29 Oct 2013 17:22:21 -0700 Subject: [PATCH] openvswitch: Per cpu flow stats. With mega flow implementation ovs flow can be shared between multiple CPUs which makes stats updates highly contended operation. This patch uses per-CPU stats in cases where a flow is likely to be shared (if there is a wildcard in the 5-tuple and therefore likely to be spread by RSS). In other situations, it uses the current strategy, saving memory and allocation time. Signed-off-by: Pravin B Shelar Signed-off-by: Jesse Gross --- net/openvswitch/datapath.c | 50 +++++++--------------- net/openvswitch/flow.c | 96 +++++++++++++++++++++++++++++++++++++++--- net/openvswitch/flow.h | 29 ++++++++++--- net/openvswitch/flow_netlink.c | 56 ++++++++++++++++++++++-- net/openvswitch/flow_netlink.h | 1 + net/openvswitch/flow_table.c | 31 +++++++++++++- net/openvswitch/flow_table.h | 2 +- 7 files changed, 210 insertions(+), 55 deletions(-) diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index 5da2534..50d7782 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -251,9 +251,9 @@ void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb) OVS_CB(skb)->flow = flow; OVS_CB(skb)->pkt_key = &key; - stats_counter = &stats->n_hit; - ovs_flow_used(OVS_CB(skb)->flow, skb); + ovs_flow_stats_update(OVS_CB(skb)->flow, skb); ovs_execute_actions(dp, skb); + stats_counter = &stats->n_hit; out: /* Update datapath statistics. */ @@ -459,14 +459,6 @@ out: return err; } -static void clear_stats(struct sw_flow *flow) -{ - flow->used = 0; - flow->tcp_flags = 0; - flow->packet_count = 0; - flow->byte_count = 0; -} - static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info) { struct ovs_header *ovs_header = info->userhdr; @@ -505,7 +497,7 @@ static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info) packet->protocol = htons(ETH_P_802_2); /* Build an sw_flow for sending this packet. */ - flow = ovs_flow_alloc(); + flow = ovs_flow_alloc(false); err = PTR_ERR(flow); if (IS_ERR(flow)) goto err_kfree_skb; @@ -641,10 +633,10 @@ static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp, const int skb_orig_len = skb->len; struct nlattr *start; struct ovs_flow_stats stats; + __be16 tcp_flags; + unsigned long used; struct ovs_header *ovs_header; struct nlattr *nla; - unsigned long used; - u8 tcp_flags; int err; ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family, flags, cmd); @@ -673,24 +665,17 @@ static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp, nla_nest_end(skb, nla); - spin_lock_bh(&flow->lock); - used = flow->used; - stats.n_packets = flow->packet_count; - stats.n_bytes = flow->byte_count; - tcp_flags = (u8)ntohs(flow->tcp_flags); - spin_unlock_bh(&flow->lock); - + ovs_flow_stats_get(flow, &stats, &used, &tcp_flags); if (used && nla_put_u64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used))) goto nla_put_failure; if (stats.n_packets && - nla_put(skb, OVS_FLOW_ATTR_STATS, - sizeof(struct ovs_flow_stats), &stats)) + nla_put(skb, OVS_FLOW_ATTR_STATS, sizeof(struct ovs_flow_stats), &stats)) goto nla_put_failure; - if (tcp_flags && - nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, tcp_flags)) + if ((u8)ntohs(tcp_flags) && + nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, (u8)ntohs(tcp_flags))) goto nla_put_failure; /* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if @@ -770,6 +755,7 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info) struct datapath *dp; struct sw_flow_actions *acts = NULL; struct sw_flow_match match; + bool exact_5tuple; int error; /* Extract key. */ @@ -778,7 +764,7 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info) goto error; ovs_match_init(&match, &key, &mask); - error = ovs_nla_get_match(&match, + error = ovs_nla_get_match(&match, &exact_5tuple, a[OVS_FLOW_ATTR_KEY], a[OVS_FLOW_ATTR_MASK]); if (error) goto error; @@ -817,12 +803,11 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info) goto err_unlock_ovs; /* Allocate flow. */ - flow = ovs_flow_alloc(); + flow = ovs_flow_alloc(!exact_5tuple); if (IS_ERR(flow)) { error = PTR_ERR(flow); goto err_unlock_ovs; } - clear_stats(flow); flow->key = masked_key; flow->unmasked_key = key; @@ -866,11 +851,8 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info) reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW); /* Clear stats. */ - if (a[OVS_FLOW_ATTR_CLEAR]) { - spin_lock_bh(&flow->lock); - clear_stats(flow); - spin_unlock_bh(&flow->lock); - } + if (a[OVS_FLOW_ATTR_CLEAR]) + ovs_flow_stats_clear(flow); } ovs_unlock(); @@ -908,7 +890,7 @@ static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info) } ovs_match_init(&match, &key, NULL); - err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL); + err = ovs_nla_get_match(&match, NULL, a[OVS_FLOW_ATTR_KEY], NULL); if (err) return err; @@ -962,7 +944,7 @@ static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info) } ovs_match_init(&match, &key, NULL); - err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL); + err = ovs_nla_get_match(&match, NULL, a[OVS_FLOW_ATTR_KEY], NULL); if (err) goto unlock; diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c index b409f52..16f4b46 100644 --- a/net/openvswitch/flow.c +++ b/net/openvswitch/flow.c @@ -35,6 +35,7 @@ #include #include #include +#include #include #include #include @@ -60,10 +61,16 @@ u64 ovs_flow_used_time(unsigned long flow_jiffies) #define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF)) -void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb) +void ovs_flow_stats_update(struct sw_flow *flow, struct sk_buff *skb) { + struct flow_stats *stats; __be16 tcp_flags = 0; + if (!flow->stats.is_percpu) + stats = flow->stats.stat; + else + stats = this_cpu_ptr(flow->stats.cpu_stats); + if ((flow->key.eth.type == htons(ETH_P_IP) || flow->key.eth.type == htons(ETH_P_IPV6)) && flow->key.ip.proto == IPPROTO_TCP && @@ -71,12 +78,87 @@ void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb) tcp_flags = TCP_FLAGS_BE16(tcp_hdr(skb)); } - spin_lock(&flow->lock); - flow->used = jiffies; - flow->packet_count++; - flow->byte_count += skb->len; - flow->tcp_flags |= tcp_flags; - spin_unlock(&flow->lock); + spin_lock(&stats->lock); + stats->used = jiffies; + stats->packet_count++; + stats->byte_count += skb->len; + stats->tcp_flags |= tcp_flags; + spin_unlock(&stats->lock); +} + +static void stats_read(struct flow_stats *stats, + struct ovs_flow_stats *ovs_stats, + unsigned long *used, __be16 *tcp_flags) +{ + spin_lock(&stats->lock); + if (time_after(stats->used, *used)) + *used = stats->used; + *tcp_flags |= stats->tcp_flags; + ovs_stats->n_packets += stats->packet_count; + ovs_stats->n_bytes += stats->byte_count; + spin_unlock(&stats->lock); +} + +void ovs_flow_stats_get(struct sw_flow *flow, struct ovs_flow_stats *ovs_stats, + unsigned long *used, __be16 *tcp_flags) +{ + int cpu, cur_cpu; + + *used = 0; + *tcp_flags = 0; + memset(ovs_stats, 0, sizeof(*ovs_stats)); + + if (!flow->stats.is_percpu) { + stats_read(flow->stats.stat, ovs_stats, used, tcp_flags); + } else { + cur_cpu = get_cpu(); + for_each_possible_cpu(cpu) { + struct flow_stats *stats; + + if (cpu == cur_cpu) + local_bh_disable(); + + stats = per_cpu_ptr(flow->stats.cpu_stats, cpu); + stats_read(stats, ovs_stats, used, tcp_flags); + + if (cpu == cur_cpu) + local_bh_enable(); + } + put_cpu(); + } +} + +static void stats_reset(struct flow_stats *stats) +{ + spin_lock(&stats->lock); + stats->used = 0; + stats->packet_count = 0; + stats->byte_count = 0; + stats->tcp_flags = 0; + spin_unlock(&stats->lock); +} + +void ovs_flow_stats_clear(struct sw_flow *flow) +{ + int cpu, cur_cpu; + + if (!flow->stats.is_percpu) { + stats_reset(flow->stats.stat); + } else { + cur_cpu = get_cpu(); + + for_each_possible_cpu(cpu) { + + if (cpu == cur_cpu) + local_bh_disable(); + + stats_reset(per_cpu_ptr(flow->stats.cpu_stats, cpu)); + + if (cpu == cur_cpu) + local_bh_enable(); + } + put_cpu(); + } } static int check_header(struct sk_buff *skb, int len) diff --git a/net/openvswitch/flow.h b/net/openvswitch/flow.h index 176406d..2d770e2 100644 --- a/net/openvswitch/flow.h +++ b/net/openvswitch/flow.h @@ -19,6 +19,7 @@ #ifndef FLOW_H #define FLOW_H 1 +#include #include #include #include @@ -146,6 +147,22 @@ struct sw_flow_actions { 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_stats { + bool is_percpu; + union { + struct flow_stats *stat; + struct flow_stats __percpu *cpu_stats; + }; +}; + struct sw_flow { struct rcu_head rcu; struct hlist_node hash_node[2]; @@ -155,12 +172,7 @@ struct sw_flow { struct sw_flow_key unmasked_key; struct sw_flow_mask *mask; struct sw_flow_actions __rcu *sf_acts; - - spinlock_t lock; /* Lock for values below. */ - unsigned long used; /* Last used time (in jiffies). */ - u64 packet_count; /* Number of packets matched. */ - u64 byte_count; /* Number of bytes matched. */ - __be16 tcp_flags; /* Union of seen TCP flags. */ + struct sw_flow_stats stats; }; struct arp_eth_header { @@ -177,7 +189,10 @@ struct arp_eth_header { unsigned char ar_tip[4]; /* target IP address */ } __packed; -void ovs_flow_used(struct sw_flow *, struct sk_buff *); +void ovs_flow_stats_update(struct sw_flow *flow, struct sk_buff *skb); +void ovs_flow_stats_get(struct sw_flow *flow, struct ovs_flow_stats *stats, + unsigned long *used, __be16 *tcp_flags); +void ovs_flow_stats_clear(struct sw_flow *flow); u64 ovs_flow_used_time(unsigned long flow_jiffies); int ovs_flow_extract(struct sk_buff *, u16 in_port, struct sw_flow_key *); diff --git a/net/openvswitch/flow_netlink.c b/net/openvswitch/flow_netlink.c index 2bc1bc1..3ccb92f 100644 --- a/net/openvswitch/flow_netlink.c +++ b/net/openvswitch/flow_netlink.c @@ -266,6 +266,20 @@ static bool is_all_zero(const u8 *fp, size_t size) return true; } +static bool is_all_set(const u8 *fp, size_t size) +{ + int i; + + if (!fp) + return false; + + for (i = 0; i < size; i++) + if (fp[i] != 0xff) + return false; + + return true; +} + static int __parse_flow_nlattrs(const struct nlattr *attr, const struct nlattr *a[], u64 *attrsp, bool nz) @@ -487,8 +501,9 @@ static int metadata_from_nlattrs(struct sw_flow_match *match, u64 *attrs, return 0; } -static int ovs_key_from_nlattrs(struct sw_flow_match *match, u64 attrs, - const struct nlattr **a, bool is_mask) +static int ovs_key_from_nlattrs(struct sw_flow_match *match, bool *exact_5tuple, + u64 attrs, const struct nlattr **a, + bool is_mask) { int err; u64 orig_attrs = attrs; @@ -545,6 +560,11 @@ static int ovs_key_from_nlattrs(struct sw_flow_match *match, u64 attrs, SW_FLOW_KEY_PUT(match, eth.type, htons(ETH_P_802_2), is_mask); } + if (is_mask && exact_5tuple) { + if (match->mask->key.eth.type != htons(0xffff)) + *exact_5tuple = false; + } + if (attrs & (1 << OVS_KEY_ATTR_IPV4)) { const struct ovs_key_ipv4 *ipv4_key; @@ -567,6 +587,13 @@ static int ovs_key_from_nlattrs(struct sw_flow_match *match, u64 attrs, SW_FLOW_KEY_PUT(match, ipv4.addr.dst, ipv4_key->ipv4_dst, is_mask); attrs &= ~(1 << OVS_KEY_ATTR_IPV4); + + if (is_mask && exact_5tuple && *exact_5tuple) { + if (ipv4_key->ipv4_proto != 0xff || + ipv4_key->ipv4_src != htonl(0xffffffff) || + ipv4_key->ipv4_dst != htonl(0xffffffff)) + *exact_5tuple = false; + } } if (attrs & (1 << OVS_KEY_ATTR_IPV6)) { @@ -598,6 +625,13 @@ static int ovs_key_from_nlattrs(struct sw_flow_match *match, u64 attrs, is_mask); attrs &= ~(1 << OVS_KEY_ATTR_IPV6); + + if (is_mask && exact_5tuple && *exact_5tuple) { + if (ipv6_key->ipv6_proto != 0xff || + !is_all_set((u8 *)ipv6_key->ipv6_src, sizeof(match->key->ipv6.addr.src)) || + !is_all_set((u8 *)ipv6_key->ipv6_dst, sizeof(match->key->ipv6.addr.dst))) + *exact_5tuple = false; + } } if (attrs & (1 << OVS_KEY_ATTR_ARP)) { @@ -640,6 +674,11 @@ static int ovs_key_from_nlattrs(struct sw_flow_match *match, u64 attrs, tcp_key->tcp_dst, is_mask); } attrs &= ~(1 << OVS_KEY_ATTR_TCP); + + if (is_mask && exact_5tuple && *exact_5tuple && + (tcp_key->tcp_src != htons(0xffff) || + tcp_key->tcp_dst != htons(0xffff))) + *exact_5tuple = false; } if (attrs & (1 << OVS_KEY_ATTR_TCP_FLAGS)) { @@ -671,6 +710,11 @@ static int ovs_key_from_nlattrs(struct sw_flow_match *match, u64 attrs, udp_key->udp_dst, is_mask); } attrs &= ~(1 << OVS_KEY_ATTR_UDP); + + if (is_mask && exact_5tuple && *exact_5tuple && + (udp_key->udp_src != htons(0xffff) || + udp_key->udp_dst != htons(0xffff))) + *exact_5tuple = false; } if (attrs & (1 << OVS_KEY_ATTR_SCTP)) { @@ -756,6 +800,7 @@ static void sw_flow_mask_set(struct sw_flow_mask *mask, * attribute specifies the mask field of the wildcarded flow. */ int ovs_nla_get_match(struct sw_flow_match *match, + bool *exact_5tuple, const struct nlattr *key, const struct nlattr *mask) { @@ -803,10 +848,13 @@ int ovs_nla_get_match(struct sw_flow_match *match, } } - err = ovs_key_from_nlattrs(match, key_attrs, a, false); + err = ovs_key_from_nlattrs(match, NULL, key_attrs, a, false); if (err) return err; + if (exact_5tuple) + *exact_5tuple = true; + if (mask) { err = parse_flow_mask_nlattrs(mask, a, &mask_attrs); if (err) @@ -844,7 +892,7 @@ int ovs_nla_get_match(struct sw_flow_match *match, } } - err = ovs_key_from_nlattrs(match, mask_attrs, a, true); + err = ovs_key_from_nlattrs(match, exact_5tuple, mask_attrs, a, true); if (err) return err; } else { diff --git a/net/openvswitch/flow_netlink.h b/net/openvswitch/flow_netlink.h index 4401510..b31fbe2 100644 --- a/net/openvswitch/flow_netlink.h +++ b/net/openvswitch/flow_netlink.h @@ -45,6 +45,7 @@ int ovs_nla_put_flow(const struct sw_flow_key *, int ovs_nla_get_flow_metadata(struct sw_flow *flow, const struct nlattr *attr); int ovs_nla_get_match(struct sw_flow_match *match, + bool *exact_5tuple, const struct nlattr *, const struct nlattr *); diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c index 7b9cf2c..299ea8b 100644 --- a/net/openvswitch/flow_table.c +++ b/net/openvswitch/flow_table.c @@ -72,19 +72,42 @@ void ovs_flow_mask_key(struct sw_flow_key *dst, const struct sw_flow_key *src, *d++ = *s++ & *m++; } -struct sw_flow *ovs_flow_alloc(void) +struct sw_flow *ovs_flow_alloc(bool percpu_stats) { struct sw_flow *flow; + int cpu; flow = kmem_cache_alloc(flow_cache, GFP_KERNEL); if (!flow) return ERR_PTR(-ENOMEM); - spin_lock_init(&flow->lock); flow->sf_acts = NULL; flow->mask = NULL; + flow->stats.is_percpu = percpu_stats; + + if (!percpu_stats) { + flow->stats.stat = kzalloc(sizeof(*flow->stats.stat), GFP_KERNEL); + if (!flow->stats.stat) + goto err; + + spin_lock_init(&flow->stats.stat->lock); + } else { + flow->stats.cpu_stats = alloc_percpu(struct flow_stats); + if (!flow->stats.cpu_stats) + goto err; + + for_each_possible_cpu(cpu) { + struct flow_stats *cpu_stats; + + cpu_stats = per_cpu_ptr(flow->stats.cpu_stats, cpu); + spin_lock_init(&cpu_stats->lock); + } + } return flow; +err: + kfree(flow); + return ERR_PTR(-ENOMEM); } int ovs_flow_tbl_count(struct flow_table *table) @@ -118,6 +141,10 @@ static struct flex_array *alloc_buckets(unsigned int n_buckets) static void flow_free(struct sw_flow *flow) { kfree((struct sf_flow_acts __force *)flow->sf_acts); + if (flow->stats.is_percpu) + free_percpu(flow->stats.cpu_stats); + else + kfree(flow->stats.stat); kmem_cache_free(flow_cache, flow); } diff --git a/net/openvswitch/flow_table.h b/net/openvswitch/flow_table.h index f54aa82..1996e34 100644 --- a/net/openvswitch/flow_table.h +++ b/net/openvswitch/flow_table.h @@ -55,7 +55,7 @@ struct flow_table { int ovs_flow_init(void); void ovs_flow_exit(void); -struct sw_flow *ovs_flow_alloc(void); +struct sw_flow *ovs_flow_alloc(bool percpu_stats); void ovs_flow_free(struct sw_flow *, bool deferred); int ovs_flow_tbl_init(struct flow_table *); -- 2.7.4