Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933125Ab3FEVoq (ORCPT ); Wed, 5 Jun 2013 17:44:46 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:38022 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933056Ab3FEVgG (ORCPT ); Wed, 5 Jun 2013 17:36:06 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Emmanuel Grumbach , Ilan Peer , Johannes Berg , Lingzhu Xiang Subject: [ 100/127] iwlwifi: mvm: fix aggregation drain flow Date: Wed, 5 Jun 2013 14:34:27 -0700 Message-Id: <20130605213229.367431720@linuxfoundation.org> X-Mailer: git-send-email 1.8.3.rc0.20.gb99dd2e In-Reply-To: <20130605213217.966891866@linuxfoundation.org> References: <20130605213217.966891866@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7268 Lines: 187 3.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Emmanuel Grumbach commit e3d4bc8cc0230e8dc8033484666f03f87392a8c4 upstream. Move the counter for non-AMPDU frames to mvm. It is needed for the drain flow which happens once the ieee80211_sta has been freed, so keeping it in iwl_mvm_sta which is embed into ieee80211_sta is not a good idea. Also, since its purpose it to remove the STA in the fw only after all the frames for this station have exited the shared Tx queues, we need to decrement it in the reclaim flow. This flow can happen after ieee80211_sta has been removed, which means that we have no iwl_mvm_sta there. So we can't know what is the vif type. Hence, we know audit these frames for all the vif types. In order to avoid spawning sta_drained_wk all the time, we now check that we are in a flow in which draining might happen - only when mvmsta is NULL. This is better than previous code that would spawn sta_drained_wk all the time in AP mode. Signed-off-by: Emmanuel Grumbach Reviewed-by: Ilan Peer Reviewed-by: Johannes Berg Signed-off-by: Johannes Berg Signed-off-by: Lingzhu Xiang Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/iwlwifi/mvm/mac80211.c | 2 - drivers/net/wireless/iwlwifi/mvm/mvm.h | 1 drivers/net/wireless/iwlwifi/mvm/sta.c | 13 +++++-- drivers/net/wireless/iwlwifi/mvm/sta.h | 2 - drivers/net/wireless/iwlwifi/mvm/tx.c | 48 +++++++++++++++++++++------- 5 files changed, 48 insertions(+), 18 deletions(-) --- a/drivers/net/wireless/iwlwifi/mvm/mac80211.c +++ b/drivers/net/wireless/iwlwifi/mvm/mac80211.c @@ -886,7 +886,7 @@ static void iwl_mvm_mac_sta_notify(struc switch (cmd) { case STA_NOTIFY_SLEEP: - if (atomic_read(&mvmsta->pending_frames) > 0) + if (atomic_read(&mvm->pending_frames[mvmsta->sta_id]) > 0) ieee80211_sta_block_awake(hw, sta, true); /* * The fw updates the STA to be asleep. Tx packets on the Tx --- a/drivers/net/wireless/iwlwifi/mvm/mvm.h +++ b/drivers/net/wireless/iwlwifi/mvm/mvm.h @@ -293,6 +293,7 @@ struct iwl_mvm { struct ieee80211_sta __rcu *fw_id_to_mac_id[IWL_MVM_STATION_COUNT]; struct work_struct sta_drained_wk; unsigned long sta_drained[BITS_TO_LONGS(IWL_MVM_STATION_COUNT)]; + atomic_t pending_frames[IWL_MVM_STATION_COUNT]; /* configured by mac80211 */ u32 rts_threshold; --- a/drivers/net/wireless/iwlwifi/mvm/sta.c +++ b/drivers/net/wireless/iwlwifi/mvm/sta.c @@ -172,7 +172,7 @@ int iwl_mvm_add_sta(struct iwl_mvm *mvm, mvm_sta->max_agg_bufsize = LINK_QUAL_AGG_FRAME_LIMIT_DEF; /* HW restart, don't assume the memory has been zeroed */ - atomic_set(&mvm_sta->pending_frames, 0); + atomic_set(&mvm->pending_frames[sta_id], 0); mvm_sta->tid_disable_agg = 0; mvm_sta->tfd_queue_msk = 0; for (i = 0; i < IEEE80211_NUM_ACS; i++) @@ -360,14 +360,21 @@ int iwl_mvm_rm_sta(struct iwl_mvm *mvm, } /* + * Make sure that the tx response code sees the station as -EBUSY and + * calls the drain worker. + */ + spin_lock_bh(&mvm_sta->lock); + /* * There are frames pending on the AC queues for this station. * We need to wait until all the frames are drained... */ - if (atomic_read(&mvm_sta->pending_frames)) { - ret = iwl_mvm_drain_sta(mvm, mvm_sta, true); + if (atomic_read(&mvm->pending_frames[mvm_sta->sta_id])) { rcu_assign_pointer(mvm->fw_id_to_mac_id[mvm_sta->sta_id], ERR_PTR(-EBUSY)); + spin_unlock_bh(&mvm_sta->lock); + ret = iwl_mvm_drain_sta(mvm, mvm_sta, true); } else { + spin_unlock_bh(&mvm_sta->lock); ret = iwl_mvm_rm_sta_common(mvm, mvm_sta->sta_id); rcu_assign_pointer(mvm->fw_id_to_mac_id[mvm_sta->sta_id], NULL); } --- a/drivers/net/wireless/iwlwifi/mvm/sta.h +++ b/drivers/net/wireless/iwlwifi/mvm/sta.h @@ -273,7 +273,6 @@ struct iwl_mvm_tid_data { * @max_agg_bufsize: the maximal size of the AGG buffer for this station * @lock: lock to protect the whole struct. Since %tid_data is access from Tx * and from Tx response flow, it needs a spinlock. - * @pending_frames: number of frames for this STA on the shared Tx queues. * @tid_data: per tid data. Look at %iwl_mvm_tid_data. * * When mac80211 creates a station it reserves some space (hw->sta_data_size) @@ -288,7 +287,6 @@ struct iwl_mvm_sta { u16 tid_disable_agg; u8 max_agg_bufsize; spinlock_t lock; - atomic_t pending_frames; struct iwl_mvm_tid_data tid_data[IWL_MAX_TID_COUNT]; struct iwl_lq_sta lq_sta; struct ieee80211_vif *vif; --- a/drivers/net/wireless/iwlwifi/mvm/tx.c +++ b/drivers/net/wireless/iwlwifi/mvm/tx.c @@ -416,9 +416,8 @@ int iwl_mvm_tx_skb(struct iwl_mvm *mvm, spin_unlock(&mvmsta->lock); - if (mvmsta->vif->type == NL80211_IFTYPE_AP && - txq_id < IWL_FIRST_AMPDU_QUEUE) - atomic_inc(&mvmsta->pending_frames); + if (txq_id < IWL_FIRST_AMPDU_QUEUE) + atomic_inc(&mvm->pending_frames[mvmsta->sta_id]); return 0; @@ -678,16 +677,41 @@ static void iwl_mvm_rx_tx_cmd_single(str /* * If the txq is not an AMPDU queue, there is no chance we freed * several skbs. Check that out... - * If there are no pending frames for this STA, notify mac80211 that - * this station can go to sleep in its STA table. */ - if (txq_id < IWL_FIRST_AMPDU_QUEUE && mvmsta && - !WARN_ON(skb_freed > 1) && - mvmsta->vif->type == NL80211_IFTYPE_AP && - atomic_sub_and_test(skb_freed, &mvmsta->pending_frames)) { - ieee80211_sta_block_awake(mvm->hw, sta, false); - set_bit(sta_id, mvm->sta_drained); - schedule_work(&mvm->sta_drained_wk); + if (txq_id < IWL_FIRST_AMPDU_QUEUE && !WARN_ON(skb_freed > 1) && + atomic_sub_and_test(skb_freed, &mvm->pending_frames[sta_id])) { + if (mvmsta) { + /* + * If there are no pending frames for this STA, notify + * mac80211 that this station can go to sleep in its + * STA table. + */ + if (mvmsta->vif->type == NL80211_IFTYPE_AP) + ieee80211_sta_block_awake(mvm->hw, sta, false); + /* + * We might very well have taken mvmsta pointer while + * the station was being removed. The remove flow might + * have seen a pending_frame (because we didn't take + * the lock) even if now the queues are drained. So make + * really sure now that this the station is not being + * removed. If it is, run the drain worker to remove it. + */ + spin_lock_bh(&mvmsta->lock); + sta = rcu_dereference(mvm->fw_id_to_mac_id[sta_id]); + if (IS_ERR_OR_NULL(sta)) { + /* + * Station disappeared in the meantime: + * so we are draining. + */ + set_bit(sta_id, mvm->sta_drained); + schedule_work(&mvm->sta_drained_wk); + } + spin_unlock_bh(&mvmsta->lock); + } else if (!mvmsta) { + /* Tx response without STA, so we are draining */ + set_bit(sta_id, mvm->sta_drained); + schedule_work(&mvm->sta_drained_wk); + } } rcu_read_unlock(); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/