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-rw-r--r--net/core/dev.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/net/core/dev.c b/net/core/dev.c
index 81ff67149f62..257b29516f69 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1857,6 +1857,161 @@ static void netif_setup_tc(struct net_device *dev, unsigned int txq)
}
}
+#ifdef CONFIG_XPS
+static DEFINE_MUTEX(xps_map_mutex);
+#define xmap_dereference(P) \
+ rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
+
+void netif_reset_xps_queue(struct net_device *dev, u16 index)
+{
+ struct xps_dev_maps *dev_maps;
+ struct xps_map *map;
+ int i, pos, nonempty = 0;
+
+ mutex_lock(&xps_map_mutex);
+ dev_maps = xmap_dereference(dev->xps_maps);
+
+ if (!dev_maps)
+ goto out_no_maps;
+
+ for_each_possible_cpu(i) {
+ map = xmap_dereference(dev_maps->cpu_map[i]);
+ if (!map)
+ continue;
+
+ for (pos = 0; pos < map->len; pos++)
+ if (map->queues[pos] == index)
+ break;
+
+ if (pos < map->len) {
+ if (map->len > 1) {
+ map->queues[pos] = map->queues[--map->len];
+ } else {
+ RCU_INIT_POINTER(dev_maps->cpu_map[i], NULL);
+ kfree_rcu(map, rcu);
+ map = NULL;
+ }
+ }
+ if (map)
+ nonempty = 1;
+ }
+
+ if (!nonempty) {
+ RCU_INIT_POINTER(dev->xps_maps, NULL);
+ kfree_rcu(dev_maps, rcu);
+ }
+
+out_no_maps:
+ mutex_unlock(&xps_map_mutex);
+}
+
+int netif_set_xps_queue(struct net_device *dev, struct cpumask *mask, u16 index)
+{
+ int i, cpu, pos, map_len, alloc_len, need_set;
+ struct xps_map *map, *new_map;
+ struct xps_dev_maps *dev_maps, *new_dev_maps;
+ int nonempty = 0;
+ int numa_node_id = -2;
+ int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
+
+ new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
+ if (!new_dev_maps)
+ return -ENOMEM;
+
+ mutex_lock(&xps_map_mutex);
+
+ dev_maps = xmap_dereference(dev->xps_maps);
+
+ for_each_possible_cpu(cpu) {
+ map = dev_maps ?
+ xmap_dereference(dev_maps->cpu_map[cpu]) : NULL;
+ new_map = map;
+ if (map) {
+ for (pos = 0; pos < map->len; pos++)
+ if (map->queues[pos] == index)
+ break;
+ map_len = map->len;
+ alloc_len = map->alloc_len;
+ } else
+ pos = map_len = alloc_len = 0;
+
+ need_set = cpumask_test_cpu(cpu, mask) && cpu_online(cpu);
+#ifdef CONFIG_NUMA
+ if (need_set) {
+ if (numa_node_id == -2)
+ numa_node_id = cpu_to_node(cpu);
+ else if (numa_node_id != cpu_to_node(cpu))
+ numa_node_id = -1;
+ }
+#endif
+ if (need_set && pos >= map_len) {
+ /* Need to add queue to this CPU's map */
+ if (map_len >= alloc_len) {
+ alloc_len = alloc_len ?
+ 2 * alloc_len : XPS_MIN_MAP_ALLOC;
+ new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len),
+ GFP_KERNEL,
+ cpu_to_node(cpu));
+ if (!new_map)
+ goto error;
+ new_map->alloc_len = alloc_len;
+ for (i = 0; i < map_len; i++)
+ new_map->queues[i] = map->queues[i];
+ new_map->len = map_len;
+ }
+ new_map->queues[new_map->len++] = index;
+ } else if (!need_set && pos < map_len) {
+ /* Need to remove queue from this CPU's map */
+ if (map_len > 1)
+ new_map->queues[pos] =
+ new_map->queues[--new_map->len];
+ else
+ new_map = NULL;
+ }
+ RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], new_map);
+ }
+
+ /* Cleanup old maps */
+ for_each_possible_cpu(cpu) {
+ map = dev_maps ?
+ xmap_dereference(dev_maps->cpu_map[cpu]) : NULL;
+ if (map && xmap_dereference(new_dev_maps->cpu_map[cpu]) != map)
+ kfree_rcu(map, rcu);
+ if (new_dev_maps->cpu_map[cpu])
+ nonempty = 1;
+ }
+
+ if (nonempty) {
+ rcu_assign_pointer(dev->xps_maps, new_dev_maps);
+ } else {
+ kfree(new_dev_maps);
+ RCU_INIT_POINTER(dev->xps_maps, NULL);
+ }
+
+ if (dev_maps)
+ kfree_rcu(dev_maps, rcu);
+
+ netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
+ (numa_node_id >= 0) ? numa_node_id :
+ NUMA_NO_NODE);
+
+ mutex_unlock(&xps_map_mutex);
+
+ return 0;
+error:
+ mutex_unlock(&xps_map_mutex);
+
+ if (new_dev_maps)
+ for_each_possible_cpu(i)
+ kfree(rcu_dereference_protected(
+ new_dev_maps->cpu_map[i],
+ 1));
+ kfree(new_dev_maps);
+ return -ENOMEM;
+}
+EXPORT_SYMBOL(netif_set_xps_queue);
+
+#endif
/*
* Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
* greater then real_num_tx_queues stale skbs on the qdisc must be flushed.