net: core: devlink: add dropped stats traps field

Whenever query statistics is issued for trap, devlink subsystem
would also fill-in statistics 'dropped' field. This field indicates
the number of packets HW dropped and failed to report to the device driver,
and thus - to the devlink subsystem itself.
In case if device driver didn't register callback for hard drop
statistics querying, 'dropped' field will be omitted and not filled.

Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/devlink.h b/include/net/devlink.h
index eb045f1..57b738b 100644 (file)
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -1348,6 +1348,16 @@ struct devlink_ops {
                                     enum devlink_trap_action action,
                                     struct netlink_ext_ack *extack);
        /**
+        * @trap_drop_counter_get: Trap drop counter get function.
+        *
+        * Should be used by device drivers to report number of packets
+        * that have been dropped, and cannot be passed to the devlink
+        * subsystem by the underlying device.
+        */
+       int (*trap_drop_counter_get)(struct devlink *devlink,
+                                    const struct devlink_trap *trap,
+                                    u64 *p_drops);
+       /**
         * @trap_policer_init: Trap policer initialization function.
         *
         * Should be used by device drivers to initialize the trap policer in

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 3bdb7ea..566ddd1 100644 (file)
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -7519,8 +7519,9 @@ static void devlink_trap_stats_read(struct devlink_stats __percpu *trap_stats,
        }
 }
 
-static int devlink_trap_stats_put(struct sk_buff *msg,
-                                 struct devlink_stats __percpu *trap_stats)
+static int
+devlink_trap_group_stats_put(struct sk_buff *msg,
+                            struct devlink_stats __percpu *trap_stats)
 {
        struct devlink_stats stats;
        struct nlattr *attr;
@@ -7548,6 +7549,50 @@ nla_put_failure:
        return -EMSGSIZE;
 }
 
+static int devlink_trap_stats_put(struct sk_buff *msg, struct devlink *devlink,
+                                 const struct devlink_trap_item *trap_item)
+{
+       struct devlink_stats stats;
+       struct nlattr *attr;
+       u64 drops = 0;
+       int err;
+
+       if (devlink->ops->trap_drop_counter_get) {
+               err = devlink->ops->trap_drop_counter_get(devlink,
+                                                         trap_item->trap,
+                                                         &drops);
+               if (err)
+                       return err;
+       }
+
+       devlink_trap_stats_read(trap_item->stats, &stats);
+
+       attr = nla_nest_start(msg, DEVLINK_ATTR_STATS);
+       if (!attr)
+               return -EMSGSIZE;
+
+       if (devlink->ops->trap_drop_counter_get &&
+           nla_put_u64_64bit(msg, DEVLINK_ATTR_STATS_RX_DROPPED, drops,
+                             DEVLINK_ATTR_PAD))
+               goto nla_put_failure;
+
+       if (nla_put_u64_64bit(msg, DEVLINK_ATTR_STATS_RX_PACKETS,
+                             stats.rx_packets, DEVLINK_ATTR_PAD))
+               goto nla_put_failure;
+
+       if (nla_put_u64_64bit(msg, DEVLINK_ATTR_STATS_RX_BYTES,
+                             stats.rx_bytes, DEVLINK_ATTR_PAD))
+               goto nla_put_failure;
+
+       nla_nest_end(msg, attr);
+
+       return 0;
+
+nla_put_failure:
+       nla_nest_cancel(msg, attr);
+       return -EMSGSIZE;
+}
+
 static int devlink_nl_trap_fill(struct sk_buff *msg, struct devlink *devlink,
                                const struct devlink_trap_item *trap_item,
                                enum devlink_command cmd, u32 portid, u32 seq,
@@ -7585,7 +7630,7 @@ static int devlink_nl_trap_fill(struct sk_buff *msg, struct devlink *devlink,
        if (err)
                goto nla_put_failure;
 
-       err = devlink_trap_stats_put(msg, trap_item->stats);
+       err = devlink_trap_stats_put(msg, devlink, trap_item);
        if (err)
                goto nla_put_failure;
 
@@ -7802,7 +7847,7 @@ devlink_nl_trap_group_fill(struct sk_buff *msg, struct devlink *devlink,
                        group_item->policer_item->policer->id))
                goto nla_put_failure;
 
-       err = devlink_trap_stats_put(msg, group_item->stats);
+       err = devlink_trap_group_stats_put(msg, group_item->stats);
        if (err)
                goto nla_put_failure;