mlxsw: spectrum: Implement offload stats ndo and expose HW stats by default

Change the default statistics ndo to return HW statistics
(like the one returned by ethtool_ops).
The HW stats are collected to a cache by delayed work every 1 sec.
Implement the offload stat ndo.
Add a function to get SW statistics, to be called from this function.

Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 127 insertions, 7 deletions

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index 27bbcaf9cfcd..171f8dd19efa 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -819,9 +819,9 @@ err_span_port_mtu_update:
         return err;
 }
 
-static struct rtnl_link_stats64 *
-mlxsw_sp_port_get_stats64(struct net_device *dev,
-                          struct rtnl_link_stats64 *stats)
+int
+mlxsw_sp_port_get_sw_stats64(const struct net_device *dev,
+                             struct rtnl_link_stats64 *stats)
 {
         struct mlxsw_sp_port *mlxsw_sp_port = netdev_priv(dev);
         struct mlxsw_sp_port_pcpu_stats *p;
@@ -848,6 +848,107 @@ mlxsw_sp_port_get_stats64(struct net_device *dev,
                 tx_dropped      += p->tx_dropped;
         }
         stats->tx_dropped       = tx_dropped;
+        return 0;
+}
+
+bool mlxsw_sp_port_has_offload_stats(int attr_id)
+{
+        switch (attr_id) {
+        case IFLA_OFFLOAD_XSTATS_CPU_HIT:
+                return true;
+        }
+
+        return false;
+}
+
+int mlxsw_sp_port_get_offload_stats(int attr_id, const struct net_device *dev,
+                                    void *sp)
+{
+        switch (attr_id) {
+        case IFLA_OFFLOAD_XSTATS_CPU_HIT:
+                return mlxsw_sp_port_get_sw_stats64(dev, sp);
+        }
+
+        return -EINVAL;
+}
+
+static int mlxsw_sp_port_get_stats_raw(struct net_device *dev, int grp,
+                                       int prio, char *ppcnt_pl)
+{
+        struct mlxsw_sp_port *mlxsw_sp_port = netdev_priv(dev);
+        struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
+
+        mlxsw_reg_ppcnt_pack(ppcnt_pl, mlxsw_sp_port->local_port, grp, prio);
+        return mlxsw_reg_query(mlxsw_sp->core, MLXSW_REG(ppcnt), ppcnt_pl);
+}
+
+static int mlxsw_sp_port_get_hw_stats(struct net_device *dev,
+                                      struct rtnl_link_stats64 *stats)
+{
+        char ppcnt_pl[MLXSW_REG_PPCNT_LEN];
+        int err;
+
+        err = mlxsw_sp_port_get_stats_raw(dev, MLXSW_REG_PPCNT_IEEE_8023_CNT,
+                                          0, ppcnt_pl);
+        if (err)
+                goto out;
+
+        stats->tx_packets =
+                mlxsw_reg_ppcnt_a_frames_transmitted_ok_get(ppcnt_pl);
+        stats->rx_packets =
+                mlxsw_reg_ppcnt_a_frames_received_ok_get(ppcnt_pl);
+        stats->tx_bytes =
+                mlxsw_reg_ppcnt_a_octets_transmitted_ok_get(ppcnt_pl);
+        stats->rx_bytes =
+                mlxsw_reg_ppcnt_a_octets_received_ok_get(ppcnt_pl);
+        stats->multicast =
+                mlxsw_reg_ppcnt_a_multicast_frames_received_ok_get(ppcnt_pl);
+
+        stats->rx_crc_errors =
+                mlxsw_reg_ppcnt_a_frame_check_sequence_errors_get(ppcnt_pl);
+        stats->rx_frame_errors =
+                mlxsw_reg_ppcnt_a_alignment_errors_get(ppcnt_pl);
+
+        stats->rx_length_errors = (
+                mlxsw_reg_ppcnt_a_in_range_length_errors_get(ppcnt_pl) +
+                mlxsw_reg_ppcnt_a_out_of_range_length_field_get(ppcnt_pl) +
+                mlxsw_reg_ppcnt_a_frame_too_long_errors_get(ppcnt_pl));
+
+        stats->rx_errors = (stats->rx_crc_errors +
+                stats->rx_frame_errors + stats->rx_length_errors);
+
+out:
+        return err;
+}
+
+static void update_stats_cache(struct work_struct *work)
+{
+        struct mlxsw_sp_port *mlxsw_sp_port =
+                container_of(work, struct mlxsw_sp_port,
+                             hw_stats.update_dw.work);
+
+        if (!netif_carrier_ok(mlxsw_sp_port->dev))
+                goto out;
+
+        mlxsw_sp_port_get_hw_stats(mlxsw_sp_port->dev,
+                                   mlxsw_sp_port->hw_stats.cache);
+
+out:
+        mlxsw_core_schedule_dw(&mlxsw_sp_port->hw_stats.update_dw,
+                               MLXSW_HW_STATS_UPDATE_TIME);
+}
+
+/* Return the stats from a cache that is updated periodically,
+ * as this function might get called in an atomic context.
+ */
+static struct rtnl_link_stats64 *
+mlxsw_sp_port_get_stats64(struct net_device *dev,
+                          struct rtnl_link_stats64 *stats)
+{
+        struct mlxsw_sp_port *mlxsw_sp_port = netdev_priv(dev);
+
+        memcpy(stats, mlxsw_sp_port->hw_stats.cache, sizeof(*stats));
+
         return stats;
 }
 
@@ -1209,6 +1310,8 @@ static const struct net_device_ops mlxsw_sp_port_netdev_ops = {
         .ndo_set_mac_address    = mlxsw_sp_port_set_mac_address,
         .ndo_change_mtu         = mlxsw_sp_port_change_mtu,
         .ndo_get_stats64        = mlxsw_sp_port_get_stats64,
+        .ndo_has_offload_stats  = mlxsw_sp_port_has_offload_stats,
+        .ndo_get_offload_stats  = mlxsw_sp_port_get_offload_stats,
         .ndo_vlan_rx_add_vid    = mlxsw_sp_port_add_vid,
         .ndo_vlan_rx_kill_vid   = mlxsw_sp_port_kill_vid,
         .ndo_neigh_construct    = mlxsw_sp_router_neigh_construct,
@@ -1547,8 +1650,6 @@ static void __mlxsw_sp_port_get_stats(struct net_device *dev,
                                       enum mlxsw_reg_ppcnt_grp grp, int prio,
                                       u64 *data, int data_index)
 {
-        struct mlxsw_sp_port *mlxsw_sp_port = netdev_priv(dev);
-        struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
         struct mlxsw_sp_port_hw_stats *hw_stats;
         char ppcnt_pl[MLXSW_REG_PPCNT_LEN];
         int i, len;
@@ -1557,8 +1658,7 @@ static void __mlxsw_sp_port_get_stats(struct net_device *dev,
         err = mlxsw_sp_get_hw_stats_by_group(&hw_stats, &len, grp);
         if (err)
                 return;
-        mlxsw_reg_ppcnt_pack(ppcnt_pl, mlxsw_sp_port->local_port, grp, prio);
-        err = mlxsw_reg_query(mlxsw_sp->core, MLXSW_REG(ppcnt), ppcnt_pl);
+        mlxsw_sp_port_get_stats_raw(dev, grp, prio, ppcnt_pl);
         for (i = 0; i < len; i++)
                 data[data_index + i] = !err ? hw_stats[i].getter(ppcnt_pl) : 0;
 }
@@ -2145,6 +2245,16 @@ static int mlxsw_sp_port_create(struct mlxsw_sp *mlxsw_sp, u8 local_port,
                 goto err_alloc_stats;
         }
 
+        mlxsw_sp_port->hw_stats.cache =
+                kzalloc(sizeof(*mlxsw_sp_port->hw_stats.cache), GFP_KERNEL);
+
+        if (!mlxsw_sp_port->hw_stats.cache) {
+                err = -ENOMEM;
+                goto err_alloc_hw_stats;
+        }
+        INIT_DELAYED_WORK(&mlxsw_sp_port->hw_stats.update_dw,
+                          &update_stats_cache);
+
         dev->netdev_ops = &mlxsw_sp_port_netdev_ops;
         dev->ethtool_ops = &mlxsw_sp_port_ethtool_ops;
 
@@ -2245,6 +2355,7 @@ static int mlxsw_sp_port_create(struct mlxsw_sp *mlxsw_sp, u8 local_port,
                 goto err_core_port_init;
         }
 
+        mlxsw_core_schedule_dw(&mlxsw_sp_port->hw_stats.update_dw, 0);
         return 0;
 
 err_core_port_init:
@@ -2265,6 +2376,8 @@ err_port_system_port_mapping_set:
 err_dev_addr_init:
         mlxsw_sp_port_swid_set(mlxsw_sp_port, MLXSW_PORT_SWID_DISABLED_PORT);
 err_port_swid_set:
+        kfree(mlxsw_sp_port->hw_stats.cache);
+err_alloc_hw_stats:
         free_percpu(mlxsw_sp_port->pcpu_stats);
 err_alloc_stats:
         kfree(mlxsw_sp_port->untagged_vlans);
@@ -2281,6 +2394,7 @@ static void mlxsw_sp_port_remove(struct mlxsw_sp *mlxsw_sp, u8 local_port)
 
         if (!mlxsw_sp_port)
                 return;
+        cancel_delayed_work_sync(&mlxsw_sp_port->hw_stats.update_dw);
         mlxsw_core_port_fini(&mlxsw_sp_port->core_port);
         unregister_netdev(mlxsw_sp_port->dev); /* This calls ndo_stop */
         mlxsw_sp->ports[local_port] = NULL;
@@ -2290,6 +2404,7 @@ static void mlxsw_sp_port_remove(struct mlxsw_sp *mlxsw_sp, u8 local_port)
         mlxsw_sp_port_swid_set(mlxsw_sp_port, MLXSW_PORT_SWID_DISABLED_PORT);
         mlxsw_sp_port_module_unmap(mlxsw_sp, mlxsw_sp_port->local_port);
         free_percpu(mlxsw_sp_port->pcpu_stats);
+        kfree(mlxsw_sp_port->hw_stats.cache);
         kfree(mlxsw_sp_port->untagged_vlans);
         kfree(mlxsw_sp_port->active_vlans);
         WARN_ON_ONCE(!list_empty(&mlxsw_sp_port->vports_list));
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
index 969c250b3048..49f4cafce148 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
@@ -361,6 +361,11 @@ struct mlxsw_sp_port {
         struct list_head vports_list;
         /* TC handles */
         struct list_head mall_tc_list;
+        struct {
+                #define MLXSW_HW_STATS_UPDATE_TIME HZ
+                struct rtnl_link_stats64 *cache;
+                struct delayed_work update_dw;
+        } hw_stats;
 };
 
 struct mlxsw_sp_port *mlxsw_sp_port_lower_dev_hold(struct net_device *dev);