diff options
Diffstat (limited to 'Documentation/networking/netdevices.txt')
| -rw-r--r-- | Documentation/networking/netdevices.txt | 35 |
1 files changed, 17 insertions, 18 deletions
diff --git a/Documentation/networking/netdevices.txt b/Documentation/networking/netdevices.txt index 89358341682..0b1cf6b2a59 100644 --- a/Documentation/networking/netdevices.txt +++ b/Documentation/networking/netdevices.txt @@ -10,12 +10,12 @@ network devices. struct net_device allocation rules ================================== Network device structures need to persist even after module is unloaded and -must be allocated with kmalloc. If device has registered successfully, -it will be freed on last use by free_netdev. This is required to handle the -pathologic case cleanly (example: rmmod mydriver </sys/class/net/myeth/mtu ) +must be allocated with alloc_netdev_mqs() and friends. +If device has registered successfully, it will be freed on last use +by free_netdev(). This is required to handle the pathologic case cleanly +(example: rmmod mydriver </sys/class/net/myeth/mtu ) -There are routines in net_init.c to handle the common cases of -alloc_etherdev, alloc_netdev. These reserve extra space for driver +alloc_netdev_mqs()/alloc_netdev() reserve extra space for driver private data which gets freed when the network device is freed. If separately allocated data is attached to the network device (netdev_priv(dev)) then it is up to the module exit handler to free that. @@ -47,26 +47,25 @@ packets is preferred. struct net_device synchronization rules ======================================= -dev->open: +ndo_open: Synchronization: rtnl_lock() semaphore. Context: process -dev->stop: +ndo_stop: Synchronization: rtnl_lock() semaphore. Context: process - Note1: netif_running() is guaranteed false - Note2: dev->poll() is guaranteed to be stopped + Note: netif_running() is guaranteed false -dev->do_ioctl: +ndo_do_ioctl: Synchronization: rtnl_lock() semaphore. Context: process -dev->get_stats: +ndo_get_stats: Synchronization: dev_base_lock rwlock. Context: nominally process, but don't sleep inside an rwlock -dev->hard_start_xmit: - Synchronization: netif_tx_lock spinlock. +ndo_start_xmit: + Synchronization: __netif_tx_lock spinlock. When the driver sets NETIF_F_LLTX in dev->features this will be called without holding netif_tx_lock. In this case the driver @@ -87,20 +86,20 @@ dev->hard_start_xmit: o NETDEV_TX_LOCKED Locking failed, please retry quickly. Only valid when NETIF_F_LLTX is set. -dev->tx_timeout: - Synchronization: netif_tx_lock spinlock. +ndo_tx_timeout: + Synchronization: netif_tx_lock spinlock; all TX queues frozen. Context: BHs disabled Notes: netif_queue_stopped() is guaranteed true -dev->set_rx_mode: - Synchronization: netif_tx_lock spinlock. +ndo_set_rx_mode: + Synchronization: netif_addr_lock spinlock. Context: BHs disabled struct napi_struct synchronization rules ======================================== napi->poll: Synchronization: NAPI_STATE_SCHED bit in napi->state. Device - driver's dev->close method will invoke napi_disable() on + driver's ndo_stop method will invoke napi_disable() on all NAPI instances which will do a sleeping poll on the NAPI_STATE_SCHED napi->state bit, waiting for all pending NAPI activity to cease. |