From: Eyal Shapira <eyal@wizery.com>
Date: Wed, 27 Aug 2014 23:21:05 +0000 (+0300)
Subject: iwlwifi: mvm: disable tx aggregation on low latency vifs
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=9ecd051ecd87d0a361c85064e57b27dc825d012e;p=linux-beck.git

iwlwifi: mvm: disable tx aggregation on low latency vifs

Aggregations hit latency so disable it by default on
low latency vifs for now. Enable control over this behavior and
allow control over the max frames in an AMPDU in low latency
vifs via debugfs.

Signed-off-by: Eyal Shapira <eyalx.shapira@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
---

diff --git a/drivers/net/wireless/iwlwifi/mvm/debugfs.c b/drivers/net/wireless/iwlwifi/mvm/debugfs.c
index 1fcbc23678c4..f85d4f4519f6 100644
--- a/drivers/net/wireless/iwlwifi/mvm/debugfs.c
+++ b/drivers/net/wireless/iwlwifi/mvm/debugfs.c
@@ -1447,6 +1447,10 @@ int iwl_mvm_dbgfs_register(struct iwl_mvm *mvm, struct dentry *dbgfs_dir)
 		goto err;
 #endif
 
+	if (!debugfs_create_u8("low_latency_agg_frame_limit", S_IRUSR | S_IWUSR,
+			       mvm->debugfs_dir,
+			       &mvm->low_latency_agg_frame_limit))
+		goto err;
 	if (!debugfs_create_u8("ps_disabled", S_IRUSR,
 			       mvm->debugfs_dir, &mvm->ps_disabled))
 		goto err;
diff --git a/drivers/net/wireless/iwlwifi/mvm/mvm.h b/drivers/net/wireless/iwlwifi/mvm/mvm.h
index d6b00b97ae66..08cb26d86be2 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mvm.h
+++ b/drivers/net/wireless/iwlwifi/mvm/mvm.h
@@ -727,6 +727,8 @@ struct iwl_mvm {
 
 	/* system time of last beacon (for AP/GO interface) */
 	u32 ap_last_beacon_gp2;
+
+	u8 low_latency_agg_frame_limit;
 };
 
 /* Extract MVM priv from op_mode and _hw */
diff --git a/drivers/net/wireless/iwlwifi/mvm/ops.c b/drivers/net/wireless/iwlwifi/mvm/ops.c
index 610dbcb0dc27..e3be34f6aa41 100644
--- a/drivers/net/wireless/iwlwifi/mvm/ops.c
+++ b/drivers/net/wireless/iwlwifi/mvm/ops.c
@@ -415,6 +415,7 @@ iwl_op_mode_mvm_start(struct iwl_trans *trans, const struct iwl_cfg *cfg,
 		mvm->first_agg_queue = 12;
 	}
 	mvm->sf_state = SF_UNINIT;
+	mvm->low_latency_agg_frame_limit = 1;
 
 	mutex_init(&mvm->mutex);
 	mutex_init(&mvm->d0i3_suspend_mutex);
diff --git a/drivers/net/wireless/iwlwifi/mvm/rs.c b/drivers/net/wireless/iwlwifi/mvm/rs.c
index b7a1efcac480..940e0d025012 100644
--- a/drivers/net/wireless/iwlwifi/mvm/rs.c
+++ b/drivers/net/wireless/iwlwifi/mvm/rs.c
@@ -2855,9 +2855,15 @@ static void rs_fill_lq_cmd(struct iwl_mvm *mvm,
 	 * Tx Fifo so that it can start a transaction in the same TxOP. This
 	 * basically allows the firmware to send bursts.
 	 */
-	if (iwl_mvm_vif_low_latency(mvmvif))
+	if (iwl_mvm_vif_low_latency(mvmvif)) {
 		lq_cmd->agg_frame_cnt_limit--;
 
+		if (mvm->low_latency_agg_frame_limit)
+			lq_cmd->agg_frame_cnt_limit =
+				min(lq_cmd->agg_frame_cnt_limit,
+				    mvm->low_latency_agg_frame_limit);
+	}
+
 	if (mvmsta->vif->p2p)
 		lq_cmd->flags |= LQ_FLAG_USE_RTS_MSK;