From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Duyck Subject: [RFC PATCH 03/10] net: Rewrite netif_reset_xps_queue to allow for better code reuse Date: Fri, 29 Jun 2012 17:16:28 -0700 Message-ID: <20120630001628.29939.22682.stgit@gitlad.jf.intel.com> References: <20120630000652.29939.11108.stgit@gitlad.jf.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: davem@davemloft.net, jeffrey.t.kirsher@intel.com, edumazet@google.com, bhutchings@solarflare.com, therbert@google.com, alexander.duyck@gmail.com To: netdev@vger.kernel.org Return-path: Received: from mga11.intel.com ([192.55.52.93]:59124 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755175Ab2F3AQJ (ORCPT ); Fri, 29 Jun 2012 20:16:09 -0400 In-Reply-To: <20120630000652.29939.11108.stgit@gitlad.jf.intel.com> Sender: netdev-owner@vger.kernel.org List-ID: This patch does a minor refactor on netif_reset_xps_queue to address a few items I noticed. First is the fact that we are doing removal of queues in both netif_reset_xps_queue and netif_set_xps_queue. Since there is no need to have the code in two places I am pushing it out into a separate function and will come back in another patch and reuse the code in netif_set_xps_queue. The second item this change addresses is the fact that the Tx queues were not getting their numa_node value cleared as a part of the XPS queue reset. This patch resolves that by resetting the numa_node value if the dev_maps value is set. Signed-off-by: Alexander Duyck --- net/core/dev.c | 56 +++++++++++++++++++++++++++++++++----------------------- 1 files changed, 33 insertions(+), 23 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 4c0981b..8e259d4 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1733,45 +1733,55 @@ 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) +static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps, + int cpu, 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; + struct xps_map *map = NULL; + int pos; - 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 (dev_maps) + map = xmap_dereference(dev_maps->cpu_map[cpu]); - if (pos < map->len) { + for (pos = 0; map && pos < map->len; pos++) { + if (map->queues[pos] == index) { if (map->len > 1) { map->queues[pos] = map->queues[--map->len]; } else { - RCU_INIT_POINTER(dev_maps->cpu_map[i], NULL); + RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL); kfree_rcu(map, rcu); map = NULL; } + break; } - if (map) - nonempty = 1; } - if (!nonempty) { + return map; +} + +void netif_reset_xps_queue(struct net_device *dev, u16 index) +{ + struct xps_dev_maps *dev_maps; + int cpu; + bool active = false; + + mutex_lock(&xps_map_mutex); + dev_maps = xmap_dereference(dev->xps_maps); + + if (!dev_maps) + goto out_no_maps; + + for_each_possible_cpu(cpu) { + if (remove_xps_queue(dev_maps, cpu, index)) + active = true; + } + + if (!active) { RCU_INIT_POINTER(dev->xps_maps, NULL); kfree_rcu(dev_maps, rcu); } + netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), + NUMA_NO_NODE); out_no_maps: mutex_unlock(&xps_map_mutex); }