[ovs-dev] [PATCH] datapath: recirculation infrastructure.

Andy Zhou azhou at nicira.com
Fri Apr 11 18:23:47 UTC 2014


Had an off-line discussion with Jesse. He suggested to split this into
two patches, one for recirc action and another for hash action.

I will drop this patch. Repost this as a two patch series.

On Mon, Apr 7, 2014 at 8:13 PM, Andy Zhou <azhou at nicira.com> wrote:
> Recirculation implementation for Linux kernel data path.
>
> Signed-off-by: Andy Zhou <azhou at nicira.com>
> ---
>  datapath/actions.c      |   55 ++++++++++++++++++++++++++++++++++++++++++++++-
>  datapath/datapath.c     |   35 ++++++++++++++++++------------
>  datapath/datapath.h     |    3 ++-
>  datapath/flow.h         |    4 ++++
>  datapath/flow_netlink.c |   55 ++++++++++++++++++++++++++++++++++++++++++++++-
>  5 files changed, 135 insertions(+), 17 deletions(-)
>
> diff --git a/datapath/actions.c b/datapath/actions.c
> index 0b66e7c..81ba67e 100644
> --- a/datapath/actions.c
> +++ b/datapath/actions.c
> @@ -1,5 +1,5 @@
>  /*
> - * Copyright (c) 2007-2013 Nicira, Inc.
> + * Copyright (c) 2007-2014 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
> @@ -506,6 +506,37 @@ static int execute_set_action(struct sk_buff *skb,
>         return err;
>  }
>
> +static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
> +                                const struct nlattr *recirc_attr)
> +{
> +       const struct ovs_action_recirc *act_recirc;
> +       struct sw_flow_key *key = OVS_CB(skb)->pkt_key;
> +       struct vport *p;
> +       u32 dp_hash = 0;
> +
> +       act_recirc = (struct ovs_action_recirc *) nla_data(recirc_attr);
> +
> +       key->recirc_id = act_recirc->recirc_id;
> +       if (act_recirc->hash_alg == OVS_RECIRC_HASH_ALG_L4) {
> +               dp_hash = skb_get_rxhash(skb);
> +               /* skb_get_rxhash() can return 0 when there
> +                * is packet error. */
> +               if (!dp_hash)
> +                       dp_hash = 0x1;
> +       }
> +       key->dp_hash = dp_hash;
> +
> +       p = ovs_vport_rcu(dp, key->phy.in_port);
> +       if (unlikely(!p)) {
> +               kfree_skb(skb);
> +               return -ENODEV;
> +       }
> +
> +       ovs_dp_process_packet_with_key(p, skb);
> +
> +       return 0;
> +}
> +
>  /* Execute a list of actions against 'skb'. */
>  static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
>                         const struct nlattr *attr, int len, bool keep_skb)
> @@ -546,12 +577,34 @@ static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
>                         err = pop_vlan(skb);
>                         break;
>
> +               case OVS_ACTION_ATTR_RECIRC: {
> +                       struct sk_buff *recirc_skb;
> +                       const bool last_action = (a->nla_len == rem);
> +
> +                       if (last_action || keep_skb)
> +                               /* Clone skb if not the last action. */
> +                               recirc_skb = skb_clone(skb, GFP_ATOMIC);
> +                       else
> +                               recirc_skb = skb;
> +
> +                       err = execute_recirc(dp, recirc_skb, a);
> +
> +                       /* Return directly if recirc is the last action
> +                        * or err. */
> +                       if (last_action || err)
> +                               return err;
> +
> +                       break;
> +               }
> +
>                 case OVS_ACTION_ATTR_SET:
>                         err = execute_set_action(skb, nla_data(a));
>                         break;
>
>                 case OVS_ACTION_ATTR_SAMPLE:
>                         err = sample(dp, skb, a);
> +                       if (unlikely(err)) /* skb already freed. */
> +                               return err;
>                         break;
>                 }
>
> diff --git a/datapath/datapath.c b/datapath/datapath.c
> index c6d42db..e2a2693 100644
> --- a/datapath/datapath.c
> +++ b/datapath/datapath.c
> @@ -240,33 +240,24 @@ void ovs_dp_detach_port(struct vport *p)
>         ovs_vport_del(p);
>  }
>
> -/* Must be called with rcu_read_lock. */
> -void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
> +void ovs_dp_process_packet_with_key(const struct vport *p, struct sk_buff *skb)
>  {
>         struct datapath *dp = p->dp;
>         struct sw_flow *flow;
>         struct dp_stats_percpu *stats;
> -       struct sw_flow_key key;
> +       struct sw_flow_key *key = OVS_CB(skb)->pkt_key;
>         u64 *stats_counter;
>         u32 n_mask_hit;
> -       int error;
>
>         stats = this_cpu_ptr(dp->stats_percpu);
>
> -       /* Extract flow from 'skb' into 'key'. */
> -       error = ovs_flow_extract(skb, p->port_no, &key);
> -       if (unlikely(error)) {
> -               kfree_skb(skb);
> -               return;
> -       }
> -
>         /* Look up flow. */
> -       flow = ovs_flow_tbl_lookup_stats(&dp->table, &key, &n_mask_hit);
> +       flow = ovs_flow_tbl_lookup_stats(&dp->table, key, &n_mask_hit);
>         if (unlikely(!flow)) {
>                 struct dp_upcall_info upcall;
>
>                 upcall.cmd = OVS_PACKET_CMD_MISS;
> -               upcall.key = &key;
> +               upcall.key = key;
>                 upcall.userdata = NULL;
>                 upcall.portid = p->upcall_portid;
>                 ovs_dp_upcall(dp, skb, &upcall);
> @@ -276,7 +267,6 @@ void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
>         }
>
>         OVS_CB(skb)->flow = flow;
> -       OVS_CB(skb)->pkt_key = &key;
>
>         ovs_flow_stats_update(OVS_CB(skb)->flow, skb);
>         ovs_execute_actions(dp, skb);
> @@ -290,6 +280,23 @@ out:
>         u64_stats_update_end(&stats->sync);
>  }
>
> +/* Must be called with rcu_read_lock. */
> +void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
> +{
> +       int error;
> +       struct sw_flow_key key;
> +
> +       /* Extract flow from 'skb' into 'key'. */
> +       error = ovs_flow_extract(skb, p->port_no, &key);
> +       if (unlikely(error)) {
> +               kfree_skb(skb);
> +               return;
> +       }
> +
> +       OVS_CB(skb)->pkt_key = &key;
> +       ovs_dp_process_packet_with_key(p, skb);
> +}
> +
>  int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
>                   const struct dp_upcall_info *upcall_info)
>  {
> diff --git a/datapath/datapath.h b/datapath/datapath.h
> index 40e0f90..d3b06ee 100644
> --- a/datapath/datapath.h
> +++ b/datapath/datapath.h
> @@ -1,5 +1,5 @@
>  /*
> - * Copyright (c) 2007-2012 Nicira, Inc.
> + * Copyright (c) 2007-2014 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
> @@ -188,6 +188,7 @@ extern struct genl_family dp_vport_genl_family;
>  extern struct genl_multicast_group ovs_dp_vport_multicast_group;
>
>  void ovs_dp_process_received_packet(struct vport *, struct sk_buff *);
> +void ovs_dp_process_packet_with_key(const struct vport *, struct sk_buff *);
>  void ovs_dp_detach_port(struct vport *);
>  int ovs_dp_upcall(struct datapath *, struct sk_buff *,
>                   const struct dp_upcall_info *);
> diff --git a/datapath/flow.h b/datapath/flow.h
> index 5043a6e..3ccaec5 100644
> --- a/datapath/flow.h
> +++ b/datapath/flow.h
> @@ -68,6 +68,8 @@ static inline void ovs_flow_tun_key_init(struct ovs_key_ipv4_tunnel *tun_key,
>  }
>
>  struct sw_flow_key {
> +       u32 dp_hash;                    /* Datapath computed hash value */
> +       u32 recirc_id;                  /* Recirculation ID */
>         struct ovs_key_ipv4_tunnel tun_key;  /* Encapsulating tunnel key. */
>         struct {
>                 u32     priority;       /* Packet QoS priority. */
> @@ -190,4 +192,6 @@ u64 ovs_flow_used_time(unsigned long flow_jiffies);
>
>  int ovs_flow_extract(struct sk_buff *, u16 in_port, struct sw_flow_key *);
>
> +u32 ovs_flow_hash_symmetric_l4(struct sw_flow_key *);
> +
>  #endif /* flow.h */
> diff --git a/datapath/flow_netlink.c b/datapath/flow_netlink.c
> index 5c32cd0..207bdeb 100644
> --- a/datapath/flow_netlink.c
> +++ b/datapath/flow_netlink.c
> @@ -123,14 +123,20 @@ static bool match_validate(const struct sw_flow_match *match,
>                         | (1ULL << OVS_KEY_ATTR_ICMP)
>                         | (1ULL << OVS_KEY_ATTR_ICMPV6)
>                         | (1ULL << OVS_KEY_ATTR_ARP)
> +                       | (1ULL << OVS_KEY_ATTR_DP_HASH)
>                         | (1ULL << OVS_KEY_ATTR_ND));
>
>         /* Always allowed mask fields. */
>         mask_allowed |= ((1ULL << OVS_KEY_ATTR_TUNNEL)
>                        | (1ULL << OVS_KEY_ATTR_IN_PORT)
> -                      | (1ULL << OVS_KEY_ATTR_ETHERTYPE));
> +                      | (1ULL << OVS_KEY_ATTR_ETHERTYPE)
> +                      | (1ULL << OVS_KEY_ATTR_RECIRC_ID));
>
>         /* Check key attributes. */
> +       if (match->key->dp_hash) {
> +               mask_allowed |= (1ULL << OVS_KEY_ATTR_DP_HASH);
> +       }
> +
>         if (match->key->eth.type == htons(ETH_P_ARP)
>                         || match->key->eth.type == htons(ETH_P_RARP)) {
>                 key_expected |= 1ULL << OVS_KEY_ATTR_ARP;
> @@ -252,6 +258,8 @@ static const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
>         [OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
>         [OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
>         [OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
> +       [OVS_KEY_ATTR_DP_HASH] = sizeof(u32),
> +       [OVS_KEY_ATTR_RECIRC_ID] = sizeof(u32),
>         [OVS_KEY_ATTR_TUNNEL] = -1,
>  };
>
> @@ -455,6 +463,35 @@ static int ipv4_tun_to_nlattr(struct sk_buff *skb,
>  static int metadata_from_nlattrs(struct sw_flow_match *match,  u64 *attrs,
>                                  const struct nlattr **a, bool is_mask)
>  {
> +       if (*attrs & (1ULL << OVS_KEY_ATTR_DP_HASH)) {
> +               u32 hash_val = nla_get_u32(a[OVS_KEY_ATTR_DP_HASH]);
> +
> +               if (!is_mask && !hash_val) {
> +                       OVS_NLERR("Hash value can not be zero\n");
> +                       return -EINVAL;
> +               }
> +
> +               SW_FLOW_KEY_PUT(match, dp_hash, hash_val, is_mask);
> +               *attrs &= ~(1ULL << OVS_KEY_ATTR_DP_HASH);
> +       }
> +
> +       if (*attrs & (1ULL << OVS_KEY_ATTR_RECIRC_ID)) {
> +               u32 recirc_id = nla_get_u32(a[OVS_KEY_ATTR_RECIRC_ID]);
> +
> +               if (is_mask && (recirc_id > 0 && recirc_id < UINT_MAX)) {
> +                       OVS_NLERR("Reicrc_id mask is neither wildcard, nor exact match \n");
> +                       return -EINVAL;
> +               }
> +
> +               SW_FLOW_KEY_PUT(match, recirc_id, recirc_id, is_mask);
> +               *attrs &= ~(1ULL << OVS_KEY_ATTR_RECIRC_ID);
> +       }
> +
> +       if (is_mask) {
> +               /* Always exact match recirc_id. */
> +               SW_FLOW_KEY_PUT(match, recirc_id, UINT_MAX, is_mask);
> +       }
> +
>         if (*attrs & (1ULL << OVS_KEY_ATTR_PRIORITY)) {
>                 SW_FLOW_KEY_PUT(match, phy.priority,
>                           nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]), is_mask);
> @@ -859,6 +896,8 @@ int ovs_nla_get_flow_metadata(struct sw_flow *flow,
>         flow->key.phy.in_port = DP_MAX_PORTS;
>         flow->key.phy.priority = 0;
>         flow->key.phy.skb_mark = 0;
> +       flow->key.dp_hash = 0;
> +       flow->key.recirc_id = 0;
>         memset(tun_key, 0, sizeof(flow->key.tun_key));
>
>         err = parse_flow_nlattrs(attr, a, &attrs);
> @@ -882,6 +921,16 @@ int ovs_nla_put_flow(const struct sw_flow_key *swkey,
>         struct nlattr *nla, *encap;
>         bool is_mask = (swkey != output);
>
> +       /* Only output dp_hash and recric_id if their key values are none zero*/
> +       /* Ommitting those key attributes implies zero on the other size */
> +       if (swkey->dp_hash)
> +               if (nla_put_u32(skb, OVS_KEY_ATTR_DP_HASH, output->dp_hash))
> +                       goto nla_put_failure;
> +
> +       if (swkey->recirc_id)
> +               if (nla_put_u32(skb, OVS_KEY_ATTR_RECIRC_ID, output->recirc_id))
> +                       goto nla_put_failure;
> +
>         if (nla_put_u32(skb, OVS_KEY_ATTR_PRIORITY, output->phy.priority))
>                 goto nla_put_failure;
>
> @@ -1418,6 +1467,7 @@ int ovs_nla_copy_actions(const struct nlattr *attr,
>                 /* Expected argument lengths, (u32)-1 for variable length. */
>                 static const u32 action_lens[OVS_ACTION_ATTR_MAX + 1] = {
>                         [OVS_ACTION_ATTR_OUTPUT] = sizeof(u32),
> +                       [OVS_ACTION_ATTR_RECIRC] = sizeof(struct ovs_action_recirc),
>                         [OVS_ACTION_ATTR_USERSPACE] = (u32)-1,
>                         [OVS_ACTION_ATTR_PUSH_VLAN] = sizeof(struct ovs_action_push_vlan),
>                         [OVS_ACTION_ATTR_POP_VLAN] = 0,
> @@ -1461,6 +1511,9 @@ int ovs_nla_copy_actions(const struct nlattr *attr,
>                                 return -EINVAL;
>                         break;
>
> +               case OVS_ACTION_ATTR_RECIRC:
> +                       break;
> +
>                 case OVS_ACTION_ATTR_SET:
>                         err = validate_set(a, key, sfa, &skip_copy);
>                         if (err)
> --
> 1.7.9.5
>



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