linux/net/core/net-sysfs.h

#ifndef __NET_SYSFS_H__
#define __NET_SYSFS_H__

int netdev_kobject_init(void);
int netdev_register_kobject(struct net_device *);
void netdev_unregister_kobject(struct net_device *);
int net_rx_queue_update_kobjects(struct net_device *, int old_num, int new_num);
int netdev_queue_update_kobjects(struct net_device *net,
				 int old_num, int new_num);

#endif
[NET]: Remove in-code externs for some functions from net/core/dev.c Inconsistent prototype and real type for functions may have worse consequences, than those for variables, so move them into a header. Since they are used privately in net/core, make this file reside in the same place. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net> 2007-10-24 12:14:45 +08:00			`#ifndef __NET_SYSFS_H__`
			`#define __NET_SYSFS_H__`

			`int netdev_kobject_init(void);`
			`int netdev_register_kobject(struct net_device *);`
			`void netdev_unregister_kobject(struct net_device *);`
net: Allow changing number of RX queues after device allocation For RPS, we create a kobject for each RX queue based on the number of queues passed to alloc_netdev_mq(). However, drivers generally do not determine the numbers of hardware queues to use until much later, so this usually represents the maximum number the driver may use and not the actual number in use. For TX queues, drivers can update the actual number using netif_set_real_num_tx_queues(). Add a corresponding function for RX queues, netif_set_real_num_rx_queues(). Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net> 2010-09-27 16:24:33 +08:00			`int net_rx_queue_update_kobjects(struct net_device *, int old_num, int new_num);`
xps: Transmit Packet Steering This patch implements transmit packet steering (XPS) for multiqueue devices. XPS selects a transmit queue during packet transmission based on configuration. This is done by mapping the CPU transmitting the packet to a queue. This is the transmit side analogue to RPS-- where RPS is selecting a CPU based on receive queue, XPS selects a queue based on the CPU (previously there was an XPS patch from Eric Dumazet, but that might more appropriately be called transmit completion steering). Each transmit queue can be associated with a number of CPUs which will use the queue to send packets. This is configured as a CPU mask on a per queue basis in: /sys/class/net/eth<n>/queues/tx-<n>/xps_cpus The mappings are stored per device in an inverted data structure that maps CPUs to queues. In the netdevice structure this is an array of num_possible_cpu structures where each structure holds and array of queue_indexes for queues which that CPU can use. The benefits of XPS are improved locality in the per queue data structures. Also, transmit completions are more likely to be done nearer to the sending thread, so this should promote locality back to the socket on free (e.g. UDP). The benefits of XPS are dependent on cache hierarchy, application load, and other factors. XPS would nominally be configured so that a queue would only be shared by CPUs which are sharing a cache, the degenerative configuration woud be that each CPU has it's own queue. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. bnx2x on 16 core AMD XPS (16 queues, 1 TX queue per CPU) 1234K at 100% CPU No XPS (16 queues) 996K at 100% CPU Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 2010-11-21 21:17:27 +08:00			`int netdev_queue_update_kobjects(struct net_device *net,`
			`int old_num, int new_num);`

net: Allow changing number of RX queues after device allocation For RPS, we create a kobject for each RX queue based on the number of queues passed to alloc_netdev_mq(). However, drivers generally do not determine the numbers of hardware queues to use until much later, so this usually represents the maximum number the driver may use and not the actual number in use. For TX queues, drivers can update the actual number using netif_set_real_num_tx_queues(). Add a corresponding function for RX queues, netif_set_real_num_rx_queues(). Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net> 2010-09-27 16:24:33 +08:00			`#endif`