Commit f2cd2d3e authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net sched: use xps information for qdisc NUMA affinity 



Allocate qdisc memory according to NUMA properties of cpus included in
xps map.

To be effective, qdisc should be (re)setup after changes
of /sys/class/net/eth<n>/queues/tx-<n>/xps_cpus

I added a numa_node field in struct netdev_queue, containing NUMA node
if all cpus included in xps_cpus share same node, else -1.

Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0793f83f

include/linux/netdevice.h

+19 −1
Original line number Diff line number Diff line
@@ -508,7 +508,9 @@ struct netdev_queue { 
#ifdef CONFIG_RPS

	struct kobject		kobj;

#endif



#if defined(CONFIG_XPS) && defined(CONFIG_NUMA)

	int			numa_node;

#endif

/*

 * write mostly part

 */
@@ -523,6 +525,22 @@ struct netdev_queue { 
	u64			tx_dropped;

} ____cacheline_aligned_in_smp;



static inline int netdev_queue_numa_node_read(const struct netdev_queue *q)

{

#if defined(CONFIG_XPS) && defined(CONFIG_NUMA)

	return q->numa_node;

#else

	return -1;

#endif

}



static inline void netdev_queue_numa_node_write(struct netdev_queue *q, int node)

{

#if defined(CONFIG_XPS) && defined(CONFIG_NUMA)

	q->numa_node = node;

#endif

}



#ifdef CONFIG_RPS

/*

 * This structure holds an RPS map which can be of variable length.  The

net/core/dev.c

+3 −2
Original line number Diff line number Diff line
@@ -5125,9 +5125,10 @@ static int netif_alloc_netdev_queues(struct net_device *dev) 
	}

	dev->_tx = tx;



	for (i = 0; i < count; i++)

	for (i = 0; i < count; i++) {

		netdev_queue_numa_node_write(&tx[i], -1);

		tx[i].dev = dev;



	}

	return 0;

}

net/core/net-sysfs.c

+11 −1
Original line number Diff line number Diff line
@@ -913,6 +913,7 @@ static ssize_t store_xps_map(struct netdev_queue *queue, 
	struct xps_map *map, *new_map;

	struct xps_dev_maps *dev_maps, *new_dev_maps;

	int nonempty = 0;

	int numa_node = -2;



	if (!capable(CAP_NET_ADMIN))

		return -EPERM;
@@ -953,7 +954,14 @@ static ssize_t store_xps_map(struct netdev_queue *queue, 
			pos = map_len = alloc_len = 0;



		need_set = cpu_isset(cpu, *mask) && cpu_online(cpu);



#ifdef CONFIG_NUMA

		if (need_set) {

			if (numa_node == -2)

				numa_node = cpu_to_node(cpu);

			else if (numa_node != cpu_to_node(cpu))

				numa_node = -1;

		}

#endif

		if (need_set && pos >= map_len) {

			/* Need to add queue to this CPU's map */

			if (map_len >= alloc_len) {
@@ -1001,6 +1009,8 @@ static ssize_t store_xps_map(struct netdev_queue *queue, 
	if (dev_maps)

		call_rcu(&dev_maps->rcu, xps_dev_maps_release);



	netdev_queue_numa_node_write(queue, (numa_node >= 0) ? numa_node : -1);



	mutex_unlock(&xps_map_mutex);



	free_cpumask_var(mask);

net/sched/sch_generic.c

+3 −1
Original line number Diff line number Diff line
@@ -553,7 +553,9 @@ struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue, 
	size = QDISC_ALIGN(sizeof(*sch));

	size += ops->priv_size + (QDISC_ALIGNTO - 1);



	p = kzalloc(size, GFP_KERNEL);

	p = kzalloc_node(size, GFP_KERNEL,

			 netdev_queue_numa_node_read(dev_queue));



	if (!p)

		goto errout;

	sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p);

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