diff options
Diffstat (limited to 'net/core/dev.c')
| -rw-r--r-- | net/core/dev.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 81ff67149f6..257b29516f6 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. |