[PATCH 08/16] iwlwifi: mvm: support txq tid owner change
From: Luca Coelho <hidden>
Date: 2016-08-29 21:26:38
Subsystem:
intel wireless wifi link (iwlwifi), the rest · Maintainers:
Miri Korenblit, Linus Torvalds
From: Liad Kaufman <redacted>
Every active TXQ is assigned to a TID given through the
SCD_CONFIG_CMD, and acts as an identifier in the FW. However,
there may be cases this ownership needs to be changed.
For example, in the following scenario:
1. TID x is owner of a queue
2. Due to a shortage of queues, TID y and z share with x
3. TID x becomes inactive and needs to be removed from the
shared queue.
In this scenario, if another queue is freed and traffic on x
continues, we can't allocate it a new queue as long as it is
the owner of the first queue.
Support moving ownership of a TXQ to a different TID (same
STA) without stopping the queue.
Signed-off-by: Liad Kaufman <redacted>
Signed-off-by: Luca Coelho <redacted>
---
drivers/net/wireless/intel/iwlwifi/mvm/sta.c | 51 ++++++++++++++++++++++++++++
1 file changed, 51 insertions(+)
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index 190bf1a..e52c46b 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c@@ -850,6 +850,41 @@ out_err: return ret; } +static void iwl_mvm_change_queue_owner(struct iwl_mvm *mvm, int queue) +{ + struct iwl_scd_txq_cfg_cmd cmd = { + .scd_queue = queue, + .action = SCD_CFG_UPDATE_QUEUE_TID, + }; + s8 sta_id; + int tid; + unsigned long tid_bitmap; + int ret; + + lockdep_assert_held(&mvm->mutex); + + spin_lock_bh(&mvm->queue_info_lock); + sta_id = mvm->queue_info[queue].ra_sta_id; + tid_bitmap = mvm->queue_info[queue].tid_bitmap; + spin_unlock_bh(&mvm->queue_info_lock); + + if (WARN(!tid_bitmap, "TXQ %d has no tids assigned to it\n", queue)) + return; + + /* Find any TID for queue */ + tid = find_first_bit(&tid_bitmap, IWL_MAX_TID_COUNT + 1); + cmd.tid = tid; + cmd.tx_fifo = iwl_mvm_ac_to_tx_fifo[tid_to_mac80211_ac[tid]]; + + ret = iwl_mvm_send_cmd_pdu(mvm, SCD_QUEUE_CFG, 0, sizeof(cmd), &cmd); + if (ret) + IWL_ERR(mvm, "Failed to update owner of TXQ %d (ret=%d)\n", + queue, ret); + else + IWL_DEBUG_TX_QUEUES(mvm, "Changed TXQ %d ownership to tid %d\n", + queue, tid); +} + static void iwl_mvm_unshare_queue(struct iwl_mvm *mvm, int queue) { struct ieee80211_sta *sta;
@@ -1005,14 +1040,30 @@ void iwl_mvm_add_new_dqa_stream_wk(struct work_struct *wk) /* Reconfigure queues requiring reconfiguation */ for (queue = 0; queue < IWL_MAX_HW_QUEUES; queue++) { bool reconfig; + bool change_owner; spin_lock_bh(&mvm->queue_info_lock); reconfig = (mvm->queue_info[queue].status == IWL_MVM_QUEUE_RECONFIGURING); + + /* + * We need to take into account a situation in which a TXQ was + * allocated to TID x, and then turned shared by adding TIDs y + * and z. If TID x becomes inactive and is removed from the TXQ, + * ownership must be given to one of the remaining TIDs. + * This is mainly because if TID x continues - a new queue can't + * be allocated for it as long as it is an owner of another TXQ. + */ + change_owner = !(mvm->queue_info[queue].tid_bitmap & + BIT(mvm->queue_info[queue].txq_tid)) && + (mvm->queue_info[queue].status == + IWL_MVM_QUEUE_SHARED); spin_unlock_bh(&mvm->queue_info_lock); if (reconfig) iwl_mvm_unshare_queue(mvm, queue); + else if (change_owner) + iwl_mvm_change_queue_owner(mvm, queue); } /* Go over all stations with deferred traffic */
--
2.8.1