[PATCH net-next v2 1/2] netdev: Add queue stats for TX stop and wake

[Daniel Jurgens <danielj@nvidia.com>]

TX queue stop and wake are counted by some drivers.
Support reporting these via netdev-genl queue stats.

Signed-off-by: Daniel Jurgens <danielj@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
---
 Documentation/netlink/specs/netdev.yaml | 14 ++++++++++++++
 include/net/netdev_queues.h             |  3 +++
 include/uapi/linux/netdev.h             |  2 ++
 net/core/netdev-genl.c                  |  4 +++-
 tools/include/uapi/linux/netdev.h       |  2 ++
 5 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index 2be4b3714d17..11a32373365a 100644
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -439,6 +439,20 @@ attribute-sets:
           Number of the packets dropped by the device due to the transmit
           packets bitrate exceeding the device rate limit.
         type: uint
+      -
+        name: tx-stop
+        doc: |
+          Number of times driver paused accepting new tx packets
+          from the stack to this queue, because the queue was full.
+          Note that if BQL is supported and enabled on the device
+          the networking stack will avoid queuing a lot of data at once.
+        type: uint
+      -
+        name: tx-wake
+        doc: |
+          Number of times driver re-started accepting send
+          requests to this queue from the stack.
+        type: uint
 
 operations:
   list:
diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h
index e7b84f018cee..a8a7e48dfa6c 100644
--- a/include/net/netdev_queues.h
+++ b/include/net/netdev_queues.h
@@ -41,6 +41,9 @@ struct netdev_queue_stats_tx {
 	u64 hw_gso_wire_bytes;
 
 	u64 hw_drop_ratelimits;
+
+	u64 stop;
+	u64 wake;
 };
 
 /**
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index cf24f1d9adf8..a8188202413e 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -165,6 +165,8 @@ enum {
 	NETDEV_A_QSTATS_TX_HW_GSO_WIRE_PACKETS,
 	NETDEV_A_QSTATS_TX_HW_GSO_WIRE_BYTES,
 	NETDEV_A_QSTATS_TX_HW_DROP_RATELIMITS,
+	NETDEV_A_QSTATS_TX_STOP,
+	NETDEV_A_QSTATS_TX_WAKE,
 
 	__NETDEV_A_QSTATS_MAX,
 	NETDEV_A_QSTATS_MAX = (__NETDEV_A_QSTATS_MAX - 1)
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 4b5054087309..1f6ae6379e0f 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -517,7 +517,9 @@ netdev_nl_stats_write_tx(struct sk_buff *rsp, struct netdev_queue_stats_tx *tx)
 	    netdev_stat_put(rsp, NETDEV_A_QSTATS_TX_HW_GSO_BYTES, tx->hw_gso_bytes) ||
 	    netdev_stat_put(rsp, NETDEV_A_QSTATS_TX_HW_GSO_WIRE_PACKETS, tx->hw_gso_wire_packets) ||
 	    netdev_stat_put(rsp, NETDEV_A_QSTATS_TX_HW_GSO_WIRE_BYTES, tx->hw_gso_wire_bytes) ||
-	    netdev_stat_put(rsp, NETDEV_A_QSTATS_TX_HW_DROP_RATELIMITS, tx->hw_drop_ratelimits))
+	    netdev_stat_put(rsp, NETDEV_A_QSTATS_TX_HW_DROP_RATELIMITS, tx->hw_drop_ratelimits) ||
+	    netdev_stat_put(rsp, NETDEV_A_QSTATS_TX_STOP, tx->stop) ||
+	    netdev_stat_put(rsp, NETDEV_A_QSTATS_TX_WAKE, tx->wake))
 		return -EMSGSIZE;
 	return 0;
 }
diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
index cf24f1d9adf8..a8188202413e 100644
--- a/tools/include/uapi/linux/netdev.h
+++ b/tools/include/uapi/linux/netdev.h
@@ -165,6 +165,8 @@ enum {
 	NETDEV_A_QSTATS_TX_HW_GSO_WIRE_PACKETS,
 	NETDEV_A_QSTATS_TX_HW_GSO_WIRE_BYTES,
 	NETDEV_A_QSTATS_TX_HW_DROP_RATELIMITS,
+	NETDEV_A_QSTATS_TX_STOP,
+	NETDEV_A_QSTATS_TX_WAKE,
 
 	__NETDEV_A_QSTATS_MAX,
 	NETDEV_A_QSTATS_MAX = (__NETDEV_A_QSTATS_MAX - 1)
-- 
2.45.0