enic: Add Accelerated RFS support
This patch adds supports for Accelerated Receive Flow Steering.
When the desired rx is different from current rq, for a flow, kernel calls the
driver function enic_rx_flow_steer(). enic_rx_flow_steer adds a IP-TCP/UDP
hardware filter.
Driver registers a timer function enic_flow_may_expire. This function is called
every HZ/4 seconds. In this function we check if the added filter has expired
by calling rps_may_expire_flow(). If the flow has expired, it removes the hw
filter.
As of now adaptor supports only IPv4 - TCP/UDP filters.
Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/cisco/enic/enic_clsf.c b/drivers/net/ethernet/cisco/enic/enic_clsf.c
index f6703c4..7f27a4c7 100644
--- a/drivers/net/ethernet/cisco/enic/enic_clsf.c
+++ b/drivers/net/ethernet/cisco/enic/enic_clsf.c
@@ -64,3 +64,216 @@
return ret;
}
+
+#ifdef CONFIG_RFS_ACCEL
+void enic_flow_may_expire(unsigned long data)
+{
+ struct enic *enic = (struct enic *)data;
+ bool res;
+ int j;
+
+ spin_lock(&enic->rfs_h.lock);
+ for (j = 0; j < ENIC_CLSF_EXPIRE_COUNT; j++) {
+ struct hlist_head *hhead;
+ struct hlist_node *tmp;
+ struct enic_rfs_fltr_node *n;
+
+ hhead = &enic->rfs_h.ht_head[enic->rfs_h.toclean++];
+ hlist_for_each_entry_safe(n, tmp, hhead, node) {
+ res = rps_may_expire_flow(enic->netdev, n->rq_id,
+ n->flow_id, n->fltr_id);
+ if (res) {
+ res = enic_delfltr(enic, n->fltr_id);
+ if (unlikely(res))
+ continue;
+ hlist_del(&n->node);
+ kfree(n);
+ enic->rfs_h.free++;
+ }
+ }
+ }
+ spin_unlock(&enic->rfs_h.lock);
+ mod_timer(&enic->rfs_h.rfs_may_expire, jiffies + HZ/4);
+}
+
+/* enic_rfs_flw_tbl_init - initialize enic->rfs_h members
+ * @enic: enic data
+ */
+void enic_rfs_flw_tbl_init(struct enic *enic)
+{
+ int i;
+
+ spin_lock_init(&enic->rfs_h.lock);
+ for (i = 0; i <= ENIC_RFS_FLW_MASK; i++)
+ INIT_HLIST_HEAD(&enic->rfs_h.ht_head[i]);
+ enic->rfs_h.max = enic->config.num_arfs;
+ enic->rfs_h.free = enic->rfs_h.max;
+ enic->rfs_h.toclean = 0;
+ init_timer(&enic->rfs_h.rfs_may_expire);
+ enic->rfs_h.rfs_may_expire.function = enic_flow_may_expire;
+ enic->rfs_h.rfs_may_expire.data = (unsigned long)enic;
+ mod_timer(&enic->rfs_h.rfs_may_expire, jiffies + HZ/4);
+}
+
+void enic_rfs_flw_tbl_free(struct enic *enic)
+{
+ int i, res;
+
+ del_timer_sync(&enic->rfs_h.rfs_may_expire);
+ spin_lock(&enic->rfs_h.lock);
+ enic->rfs_h.free = 0;
+ for (i = 0; i < (1 << ENIC_RFS_FLW_BITSHIFT); i++) {
+ struct hlist_head *hhead;
+ struct hlist_node *tmp;
+ struct enic_rfs_fltr_node *n;
+
+ hhead = &enic->rfs_h.ht_head[i];
+ hlist_for_each_entry_safe(n, tmp, hhead, node) {
+ enic_delfltr(enic, n->fltr_id);
+ hlist_del(&n->node);
+ kfree(n);
+ }
+ }
+ spin_unlock(&enic->rfs_h.lock);
+}
+
+static struct enic_rfs_fltr_node *htbl_key_search(struct hlist_head *h,
+ struct flow_keys *k)
+{
+ struct enic_rfs_fltr_node *tpos;
+
+ hlist_for_each_entry(tpos, h, node)
+ if (tpos->keys.src == k->src &&
+ tpos->keys.dst == k->dst &&
+ tpos->keys.ports == k->ports &&
+ tpos->keys.ip_proto == k->ip_proto &&
+ tpos->keys.n_proto == k->n_proto)
+ return tpos;
+ return NULL;
+}
+
+int enic_rx_flow_steer(struct net_device *dev, const struct sk_buff *skb,
+ u16 rxq_index, u32 flow_id)
+{
+ struct flow_keys keys;
+ struct enic_rfs_fltr_node *n;
+ struct enic *enic;
+ u16 tbl_idx;
+ int res, i;
+
+ enic = netdev_priv(dev);
+ res = skb_flow_dissect(skb, &keys);
+ if (!res || keys.n_proto != htons(ETH_P_IP) ||
+ (keys.ip_proto != IPPROTO_TCP && keys.ip_proto != IPPROTO_UDP))
+ return -EPROTONOSUPPORT;
+
+ tbl_idx = skb_get_hash_raw(skb) & ENIC_RFS_FLW_MASK;
+ spin_lock(&enic->rfs_h.lock);
+ n = htbl_key_search(&enic->rfs_h.ht_head[tbl_idx], &keys);
+
+ if (n) { /* entry already present */
+ if (rxq_index == n->rq_id) {
+ res = -EEXIST;
+ goto ret_unlock;
+ }
+
+ /* desired rq changed for the flow, we need to delete
+ * old fltr and add new one
+ *
+ * The moment we delete the fltr, the upcoming pkts
+ * are put it default rq based on rss. When we add
+ * new filter, upcoming pkts are put in desired queue.
+ * This could cause ooo pkts.
+ *
+ * Lets 1st try adding new fltr and then del old one.
+ */
+ i = --enic->rfs_h.free;
+ /* clsf tbl is full, we have to del old fltr first*/
+ if (unlikely(i < 0)) {
+ enic->rfs_h.free++;
+ res = enic_delfltr(enic, n->fltr_id);
+ if (unlikely(res < 0))
+ goto ret_unlock;
+ res = enic_addfltr_5t(enic, &keys, rxq_index);
+ if (res < 0) {
+ hlist_del(&n->node);
+ enic->rfs_h.free++;
+ goto ret_unlock;
+ }
+ /* add new fltr 1st then del old fltr */
+ } else {
+ int ret;
+
+ res = enic_addfltr_5t(enic, &keys, rxq_index);
+ if (res < 0) {
+ enic->rfs_h.free++;
+ goto ret_unlock;
+ }
+ ret = enic_delfltr(enic, n->fltr_id);
+ /* deleting old fltr failed. Add old fltr to list.
+ * enic_flow_may_expire() will try to delete it later.
+ */
+ if (unlikely(ret < 0)) {
+ struct enic_rfs_fltr_node *d;
+ struct hlist_head *head;
+
+ head = &enic->rfs_h.ht_head[tbl_idx];
+ d = kmalloc(sizeof(*d), GFP_ATOMIC);
+ if (d) {
+ d->fltr_id = n->fltr_id;
+ INIT_HLIST_NODE(&d->node);
+ hlist_add_head(&d->node, head);
+ }
+ } else {
+ enic->rfs_h.free++;
+ }
+ }
+ n->rq_id = rxq_index;
+ n->fltr_id = res;
+ n->flow_id = flow_id;
+ /* entry not present */
+ } else {
+ i = --enic->rfs_h.free;
+ if (i <= 0) {
+ enic->rfs_h.free++;
+ res = -EBUSY;
+ goto ret_unlock;
+ }
+
+ n = kmalloc(sizeof(*n), GFP_ATOMIC);
+ if (!n) {
+ res = -ENOMEM;
+ enic->rfs_h.free++;
+ goto ret_unlock;
+ }
+
+ res = enic_addfltr_5t(enic, &keys, rxq_index);
+ if (res < 0) {
+ kfree(n);
+ enic->rfs_h.free++;
+ goto ret_unlock;
+ }
+ n->rq_id = rxq_index;
+ n->fltr_id = res;
+ n->flow_id = flow_id;
+ n->keys = keys;
+ INIT_HLIST_NODE(&n->node);
+ hlist_add_head(&n->node, &enic->rfs_h.ht_head[tbl_idx]);
+ }
+
+ret_unlock:
+ spin_unlock(&enic->rfs_h.lock);
+ return res;
+}
+
+#else
+
+void enic_rfs_flw_tbl_init(struct enic *enic)
+{
+}
+
+void enic_rfs_flw_tbl_free(struct enic *enic)
+{
+}
+
+#endif /* CONFIG_RFS_ACCEL */