nfp: flower: split and limit cmsg skb lists

[ Upstream commit cf2cbadc20f5651c3dde9f5ac2ee52fb43aa4ddd ]

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: b985f870a5f0 ("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>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/netronome/nfp/flower/cmsg.c b/drivers/net/ethernet/netronome/nfp/flower/cmsg.c
index baaea6f1a9d8a4c69ae02477bdad13d9ff5e6539..6409957e1657034ae445b1be231a455113a4a2d8 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/cmsg.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/cmsg.c
@@ -242,18 +242,49 @@ nfp_flower_cmsg_process_one_rx(struct nfp_app *app, struct sk_buff *skb)
 
 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);
@@ -270,7 +301,6 @@ void nfp_flower_cmsg_rx(struct nfp_app *app, struct sk_buff *skb)
                nfp_flower_rx_flow_stats(app, skb);
                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 329a9b6d453a7de20f0a610a75fd76e602693077..343f9117fb577f9cc7106037c558d8ed4bc8c90e 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/cmsg.h
+++ b/drivers/net/ethernet/netronome/nfp/flower/cmsg.h
@@ -98,6 +98,8 @@
 #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 742d6f1575b5a3ce66ce9c7bc7dcb98fc7e6f556..6454323be65d747bcfe35448e9b336f98852ac52 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/main.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/main.c
@@ -517,7 +517,8 @@ 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);
 
@@ -544,7 +545,8 @@ 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 332ff0fdc038dea3471822b64eacfb6953c941fc..1eca582c5846cc8e3688bcd799899a2cd3ece3a0 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/main.h
+++ b/drivers/net/ethernet/netronome/nfp/flower/main.h
@@ -89,7 +89,10 @@ struct nfp_fl_stats_id {
  * @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
@@ -117,7 +120,8 @@ 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;