Return-path: Received: from smtp.rutgers.edu ([128.6.72.243]:38272 "EHLO annwn14.rutgers.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1161544AbXDWS6U (ORCPT ); Mon, 23 Apr 2007 14:58:20 -0400 From: Michael Wu Subject: [PATCH 06/13] mac80211: avoid flush_scheduled_work Date: Mon, 23 Apr 2007 14:48:13 -0400 To: Jiri Benc Cc: linux-wireless@vger.kernel.org, John Linville Message-Id: <20070423184813.7029.75057.stgit@magic.sourmilk.net> In-Reply-To: <20070423184811.7029.24949.stgit@magic.sourmilk.net> References: <20070423184811.7029.24949.stgit@magic.sourmilk.net> Content-Type: text/plain; charset=utf-8; format=fixed Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Michael Wu flush_scheduled_work in ieee80211_if_shutdown is called with rtnl held, which can lead to deadlocks. This patch eliminates that by adding a new single thread workqueue which can be safely flushed. It is also available for driver use. Signed-off-by: Michael Wu --- include/net/mac80211.h | 4 ++++ net/mac80211/ieee80211.c | 30 +++++++++++++----------------- net/mac80211/ieee80211_iface.c | 2 +- net/mac80211/ieee80211_sta.c | 24 ++++++++++++++++-------- net/mac80211/sta_info.c | 4 ++-- 5 files changed, 36 insertions(+), 28 deletions(-) diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 6392c44..b4b6619 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -465,6 +465,10 @@ struct ieee80211_hw { /* assigned by mac80211, don't write */ struct ieee80211_conf conf; + /* Single thread workqueue available for driver use + * Allocated by mac80211 on registration */ + struct workqueue_struct *workqueue; + /* Pointer to the private area that was * allocated with this struct for you. */ void *priv; diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c index 8a3c749..25ea011 100644 --- a/net/mac80211/ieee80211.c +++ b/net/mac80211/ieee80211.c @@ -2234,18 +2234,13 @@ static void ieee80211_if_shutdown(struct net_device *dev) case IEEE80211_IF_TYPE_IBSS: sdata->u.sta.state = IEEE80211_DISABLED; del_timer_sync(&sdata->u.sta.timer); - flush_scheduled_work(); skb_queue_purge(&sdata->u.sta.skb_queue); if (!local->ops->hw_scan && local->scan_dev == sdata->dev) { local->sta_scanning = 0; cancel_delayed_work(&local->scan_work); - flush_scheduled_work(); - /* see comment in ieee80211_unregister_hw to - * understand why this works */ - local->scan_dev = NULL; - } else - flush_scheduled_work(); + } + flush_workqueue(local->hw.workqueue); break; } } @@ -2460,6 +2455,7 @@ static int ieee80211_stop(struct net_device *dev) } netif_stop_queue(dev); + ieee80211_if_shutdown(dev); if (sdata->type == IEEE80211_IF_TYPE_MNTR) { local->monitors--; @@ -2486,7 +2482,6 @@ static int ieee80211_stop(struct net_device *dev) conf.mac_addr = dev->dev_addr; local->ops->remove_interface(local_to_hw(local), &conf); } - ieee80211_if_shutdown(dev); ieee80211_start_hard_monitor(local); @@ -4726,12 +4721,20 @@ EXPORT_SYMBOL(ieee80211_alloc_hw); int ieee80211_register_hw(struct ieee80211_hw *hw) { struct ieee80211_local *local = hw_to_local(hw); + const char *name; int result; result = wiphy_register(local->hw.wiphy); if (result < 0) return result; + name = wiphy_dev(local->hw.wiphy)->driver->name; + local->hw.workqueue = create_singlethread_workqueue(name); + if (!local->hw.workqueue) { + result = -ENOMEM; + goto fail_workqueue; + } + debugfs_hw_add(local); local->hw.conf.beacon_int = 1000; @@ -4806,6 +4809,7 @@ fail_dev: sta_info_stop(local); fail_sta_info: debugfs_hw_del(local); +fail_workqueue: wiphy_unregister(local->hw.wiphy); return result; } @@ -4872,15 +4876,6 @@ void ieee80211_unregister_hw(struct ieee80211_hw *hw) if (local->stat_time) del_timer_sync(&local->stat_timer); - if (!local->ops->hw_scan && local->scan_dev) { - local->sta_scanning = 0; - cancel_delayed_work(&local->scan_work); - flush_scheduled_work(); - /* The scan_work is guaranteed not to be called at this - * point. It is not scheduled and not running now. It can be - * scheduled again only by sta_work (stopped by now) or under - * rtnl lock. */ - } ieee80211_rx_bss_list_deinit(local->mdev); ieee80211_clear_tx_pending(local); @@ -4900,6 +4895,7 @@ void ieee80211_unregister_hw(struct ieee80211_hw *hw) skb_queue_purge(&local->skb_queue); skb_queue_purge(&local->skb_queue_unreliable); + destroy_workqueue(local->hw.workqueue); wiphy_unregister(local->hw.wiphy); ieee80211_wep_free(local); ieee80211_led_exit(local); diff --git a/net/mac80211/ieee80211_iface.c b/net/mac80211/ieee80211_iface.c index 719bc21..cf0f32e 100644 --- a/net/mac80211/ieee80211_iface.c +++ b/net/mac80211/ieee80211_iface.c @@ -179,7 +179,7 @@ void ieee80211_if_set_type(struct net_device *dev, int type) ifsta = &sdata->u.sta; INIT_WORK(&ifsta->work, ieee80211_sta_work); setup_timer(&ifsta->timer, ieee80211_sta_timer, - (unsigned long) ifsta); + (unsigned long) sdata); skb_queue_head_init(&ifsta->skb_queue); ifsta->capab = WLAN_CAPABILITY_ESS; diff --git a/net/mac80211/ieee80211_sta.c b/net/mac80211/ieee80211_sta.c index 3d16ed8..0e9e4f9 100644 --- a/net/mac80211/ieee80211_sta.c +++ b/net/mac80211/ieee80211_sta.c @@ -1730,6 +1730,7 @@ static void ieee80211_rx_mgmt_probe_req(struct net_device *dev, void ieee80211_sta_rx_mgmt(struct net_device *dev, struct sk_buff *skb, struct ieee80211_rx_status *rx_status) { + struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); struct ieee80211_sub_if_data *sdata; struct ieee80211_if_sta *ifsta; struct ieee80211_mgmt *mgmt; @@ -1755,7 +1756,7 @@ void ieee80211_sta_rx_mgmt(struct net_device *dev, struct sk_buff *skb, case IEEE80211_STYPE_DEAUTH: case IEEE80211_STYPE_DISASSOC: skb_queue_tail(&ifsta->skb_queue, skb); - schedule_work(&ifsta->work); + queue_work(local->hw.workqueue, &ifsta->work); return; default: printk(KERN_DEBUG "%s: received unknown management frame - " @@ -1900,9 +1901,13 @@ static void ieee80211_sta_merge_ibss(struct net_device *dev, void ieee80211_sta_timer(unsigned long data) { - struct ieee80211_if_sta *ifsta = (struct ieee80211_if_sta *) data; + struct ieee80211_sub_if_data *sdata = + (struct ieee80211_sub_if_data *) data; + struct ieee80211_if_sta *ifsta = &sdata->u.sta; + struct ieee80211_local *local = wdev_priv(&sdata->wdev); + set_bit(IEEE80211_STA_REQ_RUN, &ifsta->request); - schedule_work(&ifsta->work); + queue_work(local->hw.workqueue, &ifsta->work); } @@ -2013,6 +2018,7 @@ static void ieee80211_sta_reset_auth(struct net_device *dev, void ieee80211_sta_req_auth(struct net_device *dev, struct ieee80211_if_sta *ifsta) { + struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); if (sdata->type != IEEE80211_IF_TYPE_STA) @@ -2021,7 +2027,7 @@ void ieee80211_sta_req_auth(struct net_device *dev, if ((ifsta->bssid_set || ifsta->auto_bssid_sel) && (ifsta->ssid_set || ifsta->auto_ssid_sel)) { set_bit(IEEE80211_STA_REQ_AUTH, &ifsta->request); - schedule_work(&ifsta->work); + queue_work(local->hw.workqueue, &ifsta->work); } } @@ -2574,7 +2580,7 @@ void ieee80211_scan_completed(struct ieee80211_hw *hw) if (sdata->type == IEEE80211_IF_TYPE_STA) { if (sdata->u.sta.associated) ieee80211_send_nullfunc(local, sdata, 0); - ieee80211_sta_timer((unsigned long)&sdata->u.sta); + ieee80211_sta_timer((unsigned long)sdata); } netif_wake_queue(sdata->dev); } @@ -2666,7 +2672,8 @@ void ieee80211_sta_scan_work(struct work_struct *work) } if (local->sta_scanning) - schedule_delayed_work(&local->scan_work, next_delay); + queue_delayed_work(local->hw.workqueue, &local->scan_work, + next_delay); } @@ -2735,7 +2742,8 @@ static int ieee80211_sta_start_scan(struct net_device *dev, local->scan_channel_idx = 0; local->scan_dev = dev; /* TODO: start scan as soon as all nullfunc frames are ACKed */ - schedule_delayed_work(&local->scan_work, IEEE80211_CHANNEL_TIME); + queue_delayed_work(local->hw.workqueue, &local->scan_work, + IEEE80211_CHANNEL_TIME); return 0; } @@ -2757,7 +2765,7 @@ int ieee80211_sta_req_scan(struct net_device *dev, u8 *ssid, size_t ssid_len) } set_bit(IEEE80211_STA_REQ_SCAN, &ifsta->request); - schedule_work(&ifsta->work); + queue_work(local->hw.workqueue, &ifsta->work); return 0; } diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 4e341f6..62f90b4 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -184,7 +184,7 @@ struct sta_info * sta_info_add(struct ieee80211_local *local, /* procfs entry adding might sleep, so schedule process context * task for adding proc entry for STAs that do not yet have * one. */ - schedule_work(&local->sta_proc_add); + queue_work(local->hw.workqueue, &local->sta_proc_add); } return sta; @@ -275,7 +275,7 @@ void sta_info_free(struct sta_info *sta, int locked) if (in_atomic()) { list_add(&sta->list, &local->deleted_sta_list); - schedule_work(&local->sta_proc_add); + queue_work(local->hw.workqueue, &local->sta_proc_add); } else finish_sta_info_free(local, sta); }