HOWTO for multiqueue network device support =========================================== Section 1: Base driver requirements for implementing multiqueue support Intro: Kernel support for multiqueue devices --------------------------------------------------------- Kernel support for multiqueue devices is always present. Section 1: Base driver requirements for implementing multiqueue support ----------------------------------------------------------------------- Base drivers are required to use the new alloc_etherdev_mq() or alloc_netdev_mq() functions to allocate the subqueues for the device. The underlying kernel API will take care of the allocation and deallocation of the subqueue memory, as well as netdev configuration of where the queues exist in memory. The base driver will also need to manage the queues as it does the global netdev->queue_lock today. Therefore base drivers should use the netif_{start|stop|wake}_subqueue() functions to manage each queue while the device is still operational. netdev->queue_lock is still used when the device comes online or when it's completely shut down (unregister_netdev(), etc.). Finally, the base driver should indicate that it is a multiqueue device. The feature flag NETIF_F_MULTI_QUEUE should be added to the netdev->features bitmap on device initialization. Below is an example from e1000: #ifdef CONFIG_E1000_MQ if ( (adapter->hw.mac.type == e1000_82571) || (adapter->hw.mac.type == e1000_82572) || (adapter->hw.mac.type == e1000_80003es2lan)) netdev->features |= NETIF_F_MULTI_QUEUE; #endif Author: Peter P. Waskiewicz Jr.