Initial implementation of sFlow.

[sliver-openvswitch.git] / datapath / actions.c

diff --git a/datapath/actions.c b/datapath/actions.c
index 1526328..7c618cc 100644 (file)
--- a/datapath/actions.c
+++ b/datapath/actions.c
@@ -37,7 +37,7 @@ make_writable(struct sk_buff *skb, unsigned min_headroom, gfp_t gfp)
                        nskb->ip_summed = skb->ip_summed;
                        nskb->csum = skb->csum;
 #endif
-#if defined(CONFIG_XEN) && LINUX_VERSION_CODE == KERNEL_VERSION(2,6,18)
+#if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID)
                        /* These fields are copied in skb_clone but not in
                         * skb_copy or related functions.  We need to manually
                         * copy them over here. */
@@ -112,7 +112,7 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
                 * when we send the packet out on the wire, and it will fail at
                 * that point because skb_checksum_setup() will not look inside
                 * an 802.1Q header. */
-               skb_checksum_setup(skb);
+               vswitch_skb_checksum_setup(skb);
 
                /* GSO is not implemented for packets with an 802.1Q header, so
                 * we have to do segmentation before we add that header.
@@ -275,8 +275,8 @@ set_tp_port(struct sk_buff *skb, struct odp_flow_key *key,
                u16 *f = a->type == ODPAT_SET_TP_SRC ? &th->source : &th->dest;
                u16 old = *f;
                u16 new = a->tp_port;
-               update_csum((u16*)((u8*)skb->data + check_ofs),
-                           skb, old, new, 1);
+               update_csum((u16*)(skb_transport_header(skb) + check_ofs), 
+                               skb, old, new, 1);
                *f = new;
        }
        return skb;
@@ -323,7 +323,7 @@ do_output(struct datapath *dp, struct sk_buff *skb, int out_port)
        dev = skb->dev = p->dev;
        if (is_dp_dev(dev))
                dp_dev_recv(dev, skb);
-        else
+       else
                dp_xmit_skb(skb);
        return;
 
@@ -366,6 +366,33 @@ output_control(struct datapath *dp, struct sk_buff *skb, u32 arg, gfp_t gfp)
        return dp_output_control(dp, skb, _ODPL_ACTION_NR, arg);
 }
 
+/* Send a copy of this packet up to the sFlow agent, along with extra
+ * information about what happened to it. */
+static void sflow_sample(struct datapath *dp, struct sk_buff *skb,
+                        const union odp_action *a, int n_actions, gfp_t gfp)
+{
+       struct odp_sflow_sample_header *hdr;
+       unsigned int actlen = n_actions * sizeof(union odp_action);
+       unsigned int hdrlen = sizeof(struct odp_sflow_sample_header);
+       struct sk_buff *nskb;
+       int i;
+
+       nskb = skb_copy_expand(skb, actlen + hdrlen, 0, gfp);
+       if (!nskb)
+               return;
+
+       memcpy(__skb_push(nskb, actlen), a, actlen);
+       hdr = (struct odp_sflow_sample_header*)__skb_push(nskb, hdrlen);
+       hdr->n_actions = n_actions;
+       hdr->sample_pool = 0;
+       for_each_possible_cpu (i) {
+               const struct dp_stats_percpu *stats;
+               stats = per_cpu_ptr(dp->stats_percpu, i);
+               hdr->sample_pool += stats->sflow_pool;
+       }
+       dp_output_control(dp, nskb, _ODPL_SFLOW_NR, 0);
+}
+
 /* Execute a list of actions against 'skb'. */
 int execute_actions(struct datapath *dp, struct sk_buff *skb,
                    struct odp_flow_key *key,
@@ -377,7 +404,20 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
         * then freeing the original skbuff is wasteful.  So the following code
         * is slightly obscure just to avoid that. */
        int prev_port = -1;
-       int err = 0;
+       int err;
+
+       if (dp->sflow_probability) {
+               /* Increment sample pool. */
+               int cpu = get_cpu();
+               per_cpu_ptr(dp->stats_percpu, cpu)->sflow_pool++;
+               put_cpu();
+
+               /* Sample packet. */
+               if (dp->sflow_probability == UINT_MAX ||
+                   net_random() < dp->sflow_probability)
+                       sflow_sample(dp, skb, a, n_actions, gfp);
+       }
+
        for (; n_actions > 0; a++, n_actions--) {
                WARN_ON_ONCE(skb_shared(skb));
                if (prev_port != -1) {
@@ -436,5 +476,5 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
                do_output(dp, skb, prev_port);
        else
                kfree_skb(skb);
-       return err;
+       return 0;
 }