nfp: flower: split and limit cmsg skb lists

Introduce a second skb list for handling control messages and limit the
number of allowed messages. Some control messages are considered more
crucial than others, resulting in the need for a second skb list. By
splitting the list into a separate high and low priority list we can
ensure that messages on the high list get added to the head of the list
that gets processed, this however has no functional impact. Previously
there was no limit on the number of messages allowed on the queue, this
could result in the queue growing boundlessly and eventually the host
running out of memory.

Fixes: 0c9b49d3d217 ("nfp: process control messages in workqueue in flower app")
Signed-off-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/netronome/nfp/flower/cmsg.c b/drivers/net/ethernet/netronome/nfp/flower/cmsg.c
index 8ad857eb89c67794d5360142aaddc77f493f1780..577659f332e41e9b36befa3188d1644193466578 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/cmsg.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/cmsg.c
@@ -272,18 +272,49 @@ out:
 
 void nfp_flower_cmsg_process_rx(struct work_struct *work)
 {
+       struct sk_buff_head cmsg_joined;
        struct nfp_flower_priv *priv;
        struct sk_buff *skb;
 
        priv = container_of(work, struct nfp_flower_priv, cmsg_work);
+       skb_queue_head_init(&cmsg_joined);
 
-       while ((skb = skb_dequeue(&priv->cmsg_skbs)))
+       spin_lock_bh(&priv->cmsg_skbs_high.lock);
+       skb_queue_splice_tail_init(&priv->cmsg_skbs_high, &cmsg_joined);
+       spin_unlock_bh(&priv->cmsg_skbs_high.lock);
+
+       spin_lock_bh(&priv->cmsg_skbs_low.lock);
+       skb_queue_splice_tail_init(&priv->cmsg_skbs_low, &cmsg_joined);
+       spin_unlock_bh(&priv->cmsg_skbs_low.lock);
+
+       while ((skb = __skb_dequeue(&cmsg_joined)))
                nfp_flower_cmsg_process_one_rx(priv->app, skb);
 }
 
-void nfp_flower_cmsg_rx(struct nfp_app *app, struct sk_buff *skb)
+static void
+nfp_flower_queue_ctl_msg(struct nfp_app *app, struct sk_buff *skb, int type)
 {
        struct nfp_flower_priv *priv = app->priv;
+       struct sk_buff_head *skb_head;
+
+       if (type == NFP_FLOWER_CMSG_TYPE_PORT_REIFY ||
+           type == NFP_FLOWER_CMSG_TYPE_PORT_MOD)
+               skb_head = &priv->cmsg_skbs_high;
+       else
+               skb_head = &priv->cmsg_skbs_low;
+
+       if (skb_queue_len(skb_head) >= NFP_FLOWER_WORKQ_MAX_SKBS) {
+               nfp_flower_cmsg_warn(app, "Dropping queued control messages\n");
+               dev_kfree_skb_any(skb);
+               return;
+       }
+
+       skb_queue_tail(skb_head, skb);
+       schedule_work(&priv->cmsg_work);
+}
+
+void nfp_flower_cmsg_rx(struct nfp_app *app, struct sk_buff *skb)
+{
        struct nfp_flower_cmsg_hdr *cmsg_hdr;
 
        cmsg_hdr = nfp_flower_cmsg_get_hdr(skb);
@@ -307,7 +338,6 @@ void nfp_flower_cmsg_rx(struct nfp_app *app, struct sk_buff *skb)
                /* Acks from the NFP that the route is added - ignore. */
                dev_consume_skb_any(skb);
        } else {
-               skb_queue_tail(&priv->cmsg_skbs, skb);
-               schedule_work(&priv->cmsg_work);
+               nfp_flower_queue_ctl_msg(app, skb, cmsg_hdr->type);
        }
 }

diff --git a/drivers/net/ethernet/netronome/nfp/flower/cmsg.h b/drivers/net/ethernet/netronome/nfp/flower/cmsg.h
index 96bc0e33980c1066650e7aa3c6c2fcead3db8ba6..b6c0fd053a503d8f087ccca90e0d9655cecd0661 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/cmsg.h
+++ b/drivers/net/ethernet/netronome/nfp/flower/cmsg.h
@@ -108,6 +108,8 @@
 #define NFP_FL_IPV4_TUNNEL_TYPE                GENMASK(7, 4)
 #define NFP_FL_IPV4_PRE_TUN_INDEX      GENMASK(2, 0)
 
+#define NFP_FLOWER_WORKQ_MAX_SKBS      30000
+
 #define nfp_flower_cmsg_warn(app, fmt, args...)                         \
        do {                                                            \
                if (net_ratelimit())                                    \

diff --git a/drivers/net/ethernet/netronome/nfp/flower/main.c b/drivers/net/ethernet/netronome/nfp/flower/main.c
index 6357e0720f43af301451ce15df3a69b8024f3718..ad02592a82b748de1d83bfd26224e3e8b452411d 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/main.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/main.c
@@ -519,7 +519,8 @@ static int nfp_flower_init(struct nfp_app *app)
 
        app->priv = app_priv;
        app_priv->app = app;
-       skb_queue_head_init(&app_priv->cmsg_skbs);
+       skb_queue_head_init(&app_priv->cmsg_skbs_high);
+       skb_queue_head_init(&app_priv->cmsg_skbs_low);
        INIT_WORK(&app_priv->cmsg_work, nfp_flower_cmsg_process_rx);
        init_waitqueue_head(&app_priv->reify_wait_queue);
 
@@ -549,7 +550,8 @@ static void nfp_flower_clean(struct nfp_app *app)
 {
        struct nfp_flower_priv *app_priv = app->priv;
 
-       skb_queue_purge(&app_priv->cmsg_skbs);
+       skb_queue_purge(&app_priv->cmsg_skbs_high);
+       skb_queue_purge(&app_priv->cmsg_skbs_low);
        flush_work(&app_priv->cmsg_work);
 
        nfp_flower_metadata_cleanup(app);

diff --git a/drivers/net/ethernet/netronome/nfp/flower/main.h b/drivers/net/ethernet/netronome/nfp/flower/main.h
index e030b3ce45106cbe21a1dce850ae37c6deff7ed4..c67e1b54c6141e494d9f30735755ce7b6f8e2b20 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/main.h
+++ b/drivers/net/ethernet/netronome/nfp/flower/main.h
@@ -107,7 +107,10 @@ struct nfp_mtu_conf {
  * @mask_table:                Hash table used to store masks
  * @flow_table:                Hash table used to store flower rules
  * @cmsg_work:         Workqueue for control messages processing
- * @cmsg_skbs:         List of skbs for control message processing
+ * @cmsg_skbs_high:    List of higher priority skbs for control message
+ *                     processing
+ * @cmsg_skbs_low:     List of lower priority skbs for control message
+ *                     processing
  * @nfp_mac_off_list:  List of MAC addresses to offload
  * @nfp_mac_index_list:        List of unique 8-bit indexes for non NFP netdevs
  * @nfp_ipv4_off_list: List of IPv4 addresses to offload
@@ -136,7 +139,8 @@ struct nfp_flower_priv {
        DECLARE_HASHTABLE(mask_table, NFP_FLOWER_MASK_HASH_BITS);
        DECLARE_HASHTABLE(flow_table, NFP_FLOWER_HASH_BITS);
        struct work_struct cmsg_work;
-       struct sk_buff_head cmsg_skbs;
+       struct sk_buff_head cmsg_skbs_high;
+       struct sk_buff_head cmsg_skbs_low;
        struct list_head nfp_mac_off_list;
        struct list_head nfp_mac_index_list;
        struct list_head nfp_ipv4_off_list;