/* * Linux WiMAX * Mappping of generic netlink family IDs to net devices * * * Copyright (C) 2005-2006 Intel Corporation * Inaky Perez-Gonzalez * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License version * 2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA. * * * We assign a single generic netlink family ID to each device (to * simplify lookup). * * We need a way to map family ID to a wimax_dev pointer. * * The idea is to use a very simple lookup. Using a netlink attribute * with (for example) the interface name implies a heavier search over * all the network devices; seemed kind of a waste given that we know * we are looking for a WiMAX device and that most systems will have * just a single WiMAX adapter. * * We put all the WiMAX devices in the system in a linked list and * match the generic link family ID against the list. * * By using a linked list, the case of a single adapter in the system * becomes (almost) no overhead, while still working for many more. If * it ever goes beyond two, I'll be surprised. */ #include #include #include #include #include #include "wimax-internal.h" #define D_SUBMODULE id_table #include "debug-levels.h" static DEFINE_SPINLOCK(wimax_id_table_lock); static struct list_head wimax_id_table = LIST_HEAD_INIT(wimax_id_table); /* * wimax_id_table_add - add a gennetlink familiy ID / wimax_dev mapping * * @wimax_dev: WiMAX device descriptor to associate to the Generic * Netlink family ID. * * Look for an empty spot in the ID table; if none found, double the * table's size and get the first spot. */ void wimax_id_table_add(struct wimax_dev *wimax_dev) { d_fnstart(3, NULL, "(wimax_dev %p)\n", wimax_dev); spin_lock(&wimax_id_table_lock); list_add(&wimax_dev->id_table_node, &wimax_id_table); spin_unlock(&wimax_id_table_lock); d_fnend(3, NULL, "(wimax_dev %p)\n", wimax_dev); } /* * wimax_get_netdev_by_info - lookup a wimax_dev from the gennetlink info * * The generic netlink family ID has been filled out in the * nlmsghdr->nlmsg_type field, so we pull it from there, look it up in * the mapping table and reference the wimax_dev. * * When done, the reference should be dropped with * 'dev_put(wimax_dev->net_dev)'. */ struct wimax_dev *wimax_dev_get_by_genl_info( struct genl_info *info, int ifindex) { struct wimax_dev *wimax_dev = NULL; d_fnstart(3, NULL, "(info %p ifindex %d)\n", info, ifindex); spin_lock(&wimax_id_table_lock); list_for_each_entry(wimax_dev, &wimax_id_table, id_table_node) { if (wimax_dev->net_dev->ifindex == ifindex) { dev_hold(wimax_dev->net_dev); goto found; } } wimax_dev = NULL; d_printf(1, NULL, "wimax: no devices found with ifindex %d\n", ifindex); found: spin_unlock(&wimax_id_table_lock); d_fnend(3, NULL, "(info %p ifindex %d) = %p\n", info, ifindex, wimax_dev); return wimax_dev; } /* * wimax_id_table_rm - Remove a gennetlink familiy ID / wimax_dev mapping * * @id: family ID to remove from the table */ void wimax_id_table_rm(struct wimax_dev *wimax_dev) { spin_lock(&wimax_id_table_lock); list_del_init(&wimax_dev->id_table_node); spin_unlock(&wimax_id_table_lock); } /* * Release the gennetlink family id / mapping table * * On debug, verify that the table is empty upon removal. We want the * code always compiled, to ensure it doesn't bit rot. It will be * compiled out if CONFIG_BUG is disabled. */ void wimax_id_table_release(void) { struct wimax_dev *wimax_dev; #ifndef CONFIG_BUG return; #endif spin_lock(&wimax_id_table_lock); list_for_each_entry(wimax_dev, &wimax_id_table, id_table_node) { pr_err("BUG: %s wimax_dev %p ifindex %d not cleared\n", __func__, wimax_dev, wimax_dev->net_dev->ifindex); WARN_ON(1); } spin_unlock(&wimax_id_table_lock); } ee9582a827ce818aba63b5bb5f0f7a3d1e9f992cf9 parent63dfef75ed75364901d7caa52c6420cec3e73519 (diff)parent83a718d6294964fd1b227fa5f1ad001bc1fe7656 (diff)
Merge branch 'bridge-improve-cache-utilization'
Nikolay Aleksandrov says: ==================== bridge: improve cache utilization This is the first set which begins to deal with the bad bridge cache access patterns. The first patch rearranges the bridge and port structs a little so the frequently (and closely) accessed members are in the same cache line. The second patch then moves the garbage collection to a workqueue trying to improve system responsiveness under load (many fdbs) and more importantly removes the need to check if the matched entry is expired in __br_fdb_get which was a major source of false-sharing. The third patch is a preparation for the final one which If properly configured, i.e. ports bound to CPUs (thus updating "updated" locally) then the bridge's HitM goes from 100% to 0%, but even without binding we get a win because previously every lookup that iterated over the hash chain caused false-sharing due to the first cache line being used for both mac/vid and used/updated fields. Some results from tests I've run: (note that these were run in good conditions for the baseline, everything ran on a single NUMA node and there were only 3 fdbs) 1. baseline 100% Load HitM on the fdbs (between everyone who has done lookups and hit one of the 3 hash chains of the communicating src/dst fdbs) Overall 5.06% Load HitM for the bridge, first place in the list 2. patched & ports bound to CPUs 0% Local load HitM, bridge is not even in the c2c report list Also there's 3% consistent improvement in netperf tests. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat
-rw-r--r--net/bridge/br_device.c1
-rw-r--r--net/bridge/br_fdb.c34
-rw-r--r--net/bridge/br_if.c2
-rw-r--r--net/bridge/br_input.c3
-rw-r--r--net/bridge/br_ioctl.c2
-rw-r--r--net/bridge/br_netlink.c2
-rw-r--r--net/bridge/br_private.h57
-rw-r--r--net/bridge/br_stp.c2
-rw-r--r--net/bridge/br_stp_if.c4
-rw-r--r--net/bridge/br_stp_timer.c2
-rw-r--r--net/bridge/br_sysfs_br.c2
11 files changed, 59 insertions, 52 deletions
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c