Commit f835bdae authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

net: remove init_dummy_netdev() 



init_dummy_netdev() can initialize statically declared or embedded
net_devices. Such netdevs did not come from alloc_netdev_mqs().
After recent work by Breno, there are the only two cases where
we have do that.

Switch those cases to alloc_netdev_mqs() and delete init_dummy_netdev().
Dealing with static netdevs is not worth the maintenance burden.

Reviewed-by: default avatarAlexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: default avatarMatthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: default avatarJoe Damato <jdamato@fastly.com>
Link: https://patch.msgid.link/20250113003456.3904110-1-kuba@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent b1b62d6d

include/linux/netdevice.h

+0 −1
Original line number Diff line number Diff line
@@ -3238,7 +3238,6 @@ static inline void unregister_netdevice(struct net_device *dev) 


int netdev_refcnt_read(const struct net_device *dev);

void free_netdev(struct net_device *dev);

void init_dummy_netdev(struct net_device *dev);



struct net_device *netdev_get_xmit_slave(struct net_device *dev,

					 struct sk_buff *skb,

net/core/dev.c

+0 −22
Original line number Diff line number Diff line
@@ -10762,28 +10762,6 @@ static void init_dummy_netdev_core(struct net_device *dev) 
	 */

}



/**

 *	init_dummy_netdev	- init a dummy network device for NAPI

 *	@dev: device to init

 *

 *	This takes a network device structure and initializes the minimum

 *	amount of fields so it can be used to schedule NAPI polls without

 *	registering a full blown interface. This is to be used by drivers

 *	that need to tie several hardware interfaces to a single NAPI

 *	poll scheduler due to HW limitations.

 */

void init_dummy_netdev(struct net_device *dev)

{

	/* Clear everything. Note we don't initialize spinlocks

	 * as they aren't supposed to be taken by any of the

	 * NAPI code and this dummy netdev is supposed to be

	 * only ever used for NAPI polls

	 */

	memset(dev, 0, sizeof(struct net_device));

	init_dummy_netdev_core(dev);

}

EXPORT_SYMBOL_GPL(init_dummy_netdev);



/**

 *	register_netdev	- register a network device

 *	@dev: device to register

net/mptcp/protocol.c

+5 −3
Original line number Diff line number Diff line
@@ -47,7 +47,7 @@ static void __mptcp_destroy_sock(struct sock *sk); 
static void mptcp_check_send_data_fin(struct sock *sk);



DEFINE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions);

static struct net_device mptcp_napi_dev;

static struct net_device *mptcp_napi_dev;



/* Returns end sequence number of the receiver's advertised window */

static u64 mptcp_wnd_end(const struct mptcp_sock *msk)
@@ -4147,11 +4147,13 @@ void __init mptcp_proto_init(void) 
	if (percpu_counter_init(&mptcp_sockets_allocated, 0, GFP_KERNEL))

		panic("Failed to allocate MPTCP pcpu counter\n");



	init_dummy_netdev(&mptcp_napi_dev);

	mptcp_napi_dev = alloc_netdev_dummy(0);

	if (!mptcp_napi_dev)

		panic("Failed to allocate MPTCP dummy netdev\n");

	for_each_possible_cpu(cpu) {

		delegated = per_cpu_ptr(&mptcp_delegated_actions, cpu);

		INIT_LIST_HEAD(&delegated->head);

		netif_napi_add_tx(&mptcp_napi_dev, &delegated->napi,

		netif_napi_add_tx(mptcp_napi_dev, &delegated->napi,

				  mptcp_napi_poll);

		napi_enable(&delegated->napi);

	}

net/xfrm/xfrm_input.c

+6 −3
Original line number Diff line number Diff line
@@ -48,7 +48,7 @@ static DEFINE_SPINLOCK(xfrm_input_afinfo_lock); 
static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[2][AF_INET6 + 1];



static struct gro_cells gro_cells;

static struct net_device xfrm_napi_dev;

static struct net_device *xfrm_napi_dev;



static DEFINE_PER_CPU(struct xfrm_trans_tasklet, xfrm_trans_tasklet);
@@ -825,8 +825,11 @@ void __init xfrm_input_init(void) 
	int err;

	int i;



	init_dummy_netdev(&xfrm_napi_dev);

	err = gro_cells_init(&gro_cells, &xfrm_napi_dev);

	xfrm_napi_dev = alloc_netdev_dummy(0);

	if (!xfrm_napi_dev)

		panic("Failed to allocate XFRM dummy netdev\n");



	err = gro_cells_init(&gro_cells, xfrm_napi_dev);

	if (err)

		gro_cells.cells = NULL;