Merge branch 'introduce-queue-and-napi-support-in-netdev-genl-was-introduce-napi-queues-support'

Amritha Nambiar says:

====================
Introduce queue and NAPI support in netdev-genl (Was: Introduce NAPI queues support)

Add the capability to export the following via netdev-genl interface:
- queue information supported by the device
- NAPI information supported by the device

Introduce support for associating queue and NAPI instance.
Extend the netdev_genl generic netlink family for netdev
with queue and NAPI data.

The queue parameters exposed are:
- queue index
- queue type
- ifindex
- NAPI id associated with the queue

Additional rx and tx queue parameters can be exposed in follow up
patches by stashing them in netdev queue structures. XDP queue type
can also be supported in future.

The NAPI fields exposed are:
- NAPI id
- NAPI device ifindex
- Interrupt number associated with the NAPI instance
- PID for the NAPI thread

This series only supports 'get' ability for retrieving
certain queue and NAPI attributes. The 'set' ability for
configuring queue and associated NAPI instance via netdev-genl
will be submitted as a separate patch series.

Previous discussion at:
https://lore.kernel.org/netdev/c8476530638a5f4381d64db0e024ed49c2db3b02.camel@gmail.com/T/#m00999652a8b4731fbdb7bf698d2e3666c65a60e7

$ ./cli.py --spec netdev.yaml --do queue-get  --json='{"ifindex": 12, "id": 0, "type": 0}'
{'id': 0, 'ifindex': 12, 'napi-id': 593, 'type': 'rx'}

$ ./cli.py --spec netdev.yaml  --do queue-get --json='{"ifindex": 12, "id": 0, "type": 1}'
{'id': 0, 'ifindex': 12, 'napi-id': 593, 'type': 'tx'}

$ ./cli.py --spec netdev.yaml  --dump queue-get --json='{"ifindex": 12}'
[{'id': 0, 'ifindex': 12, 'napi-id': 593, 'type': 'rx'},
 {'id': 1, 'ifindex': 12, 'napi-id': 594, 'type': 'rx'},
 {'id': 2, 'ifindex': 12, 'napi-id': 595, 'type': 'rx'},
 {'id': 3, 'ifindex': 12, 'napi-id': 596, 'type': 'rx'},
 {'id': 0, 'ifindex': 12, 'napi-id': 593, 'type': 'tx'},
 {'id': 1, 'ifindex': 12, 'napi-id': 594, 'type': 'tx'},
 {'id': 2, 'ifindex': 12, 'napi-id': 595, 'type': 'tx'},
 {'id': 3, 'ifindex': 12, 'napi-id': 596, 'type': 'tx'}]

$ ./cli.py --spec netdev.yaml --do napi-get --json='{"id": 593}'
{'id': 593, 'ifindex': 12, 'irq': 291, 'pid': 3727}

$ ./cli.py --spec netdev.yaml --dump napi-get --json='{"ifindex": 12}'
[{'id': 596, 'ifindex': 12, 'irq': 294, 'pid': 3724},
 {'id': 595, 'ifindex': 12, 'irq': 293, 'pid': 3725},
 {'id': 594, 'ifindex': 12, 'irq': 292, 'pid': 3726},
 {'id': 593, 'ifindex': 12, 'irq': 291, 'pid': 3727}]
====================

Link: https://lore.kernel.org/r/170147307026.5260.9300080745237900261.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 45 insertions, 0 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index c2d74bc112dd..5551177e024e 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -382,6 +382,7 @@ struct napi_struct {
 	/* control-path-only fields follow */
 	struct list_head	dev_list;
 	struct hlist_node	napi_hash_node;
+	int			irq;
 };
 
 enum {
@@ -665,6 +666,10 @@ struct netdev_queue {
 #ifdef CONFIG_XDP_SOCKETS
 	struct xsk_buff_pool    *pool;
 #endif
+	/* NAPI instance for the queue
+	 * Readers and writers must hold RTNL
+	 */
+	struct napi_struct      *napi;
 /*
  * write-mostly part
  */
@@ -2657,6 +2662,15 @@ static inline void *netdev_priv(const struct net_device *dev)
  */
 #define SET_NETDEV_DEVTYPE(net, devtype)	((net)->dev.type = (devtype))
 
+void netif_queue_set_napi(struct net_device *dev, unsigned int queue_index,
+			  enum netdev_queue_type type,
+			  struct napi_struct *napi);
+
+static inline void netif_napi_set_irq(struct napi_struct *napi, int irq)
+{
+	napi->irq = irq;
+}
+
 /* Default NAPI poll() weight
  * Device drivers are strongly advised to not use bigger value
  */
diff --git a/include/net/netdev_rx_queue.h b/include/net/netdev_rx_queue.h
index cdcafb30d437..aa1716fb0e53 100644
--- a/include/net/netdev_rx_queue.h
+++ b/include/net/netdev_rx_queue.h
@@ -21,6 +21,10 @@ struct netdev_rx_queue {
 #ifdef CONFIG_XDP_SOCKETS
 	struct xsk_buff_pool            *pool;
 #endif
+	/* NAPI instance for the queue
+	 * Readers and writers must hold RTNL
+	 */
+	struct napi_struct		*napi;
 } ____cacheline_aligned_in_smp;
 
 /*
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index 6244c0164976..424c5e28f495 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -62,6 +62,11 @@ enum netdev_xsk_flags {
 	NETDEV_XSK_FLAGS_TX_CHECKSUM = 2,
 };
 
+enum netdev_queue_type {
+	NETDEV_QUEUE_TYPE_RX,
+	NETDEV_QUEUE_TYPE_TX,
+};
+
 enum {
 	NETDEV_A_DEV_IFINDEX = 1,
 	NETDEV_A_DEV_PAD,
@@ -105,6 +110,26 @@ enum {
 };
 
 enum {
+	NETDEV_A_NAPI_IFINDEX = 1,
+	NETDEV_A_NAPI_ID,
+	NETDEV_A_NAPI_IRQ,
+	NETDEV_A_NAPI_PID,
+
+	__NETDEV_A_NAPI_MAX,
+	NETDEV_A_NAPI_MAX = (__NETDEV_A_NAPI_MAX - 1)
+};
+
+enum {
+	NETDEV_A_QUEUE_ID = 1,
+	NETDEV_A_QUEUE_IFINDEX,
+	NETDEV_A_QUEUE_TYPE,
+	NETDEV_A_QUEUE_NAPI_ID,
+
+	__NETDEV_A_QUEUE_MAX,
+	NETDEV_A_QUEUE_MAX = (__NETDEV_A_QUEUE_MAX - 1)
+};
+
+enum {
 	NETDEV_CMD_DEV_GET = 1,
 	NETDEV_CMD_DEV_ADD_NTF,
 	NETDEV_CMD_DEV_DEL_NTF,
@@ -114,6 +139,8 @@ enum {
 	NETDEV_CMD_PAGE_POOL_DEL_NTF,
 	NETDEV_CMD_PAGE_POOL_CHANGE_NTF,
 	NETDEV_CMD_PAGE_POOL_STATS_GET,
+	NETDEV_CMD_QUEUE_GET,
+	NETDEV_CMD_NAPI_GET,
 
 	__NETDEV_CMD_MAX,
 	NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)