[3.13.y.z extended stable] Patch "iwlwifi: mvm: Add a missed beacons threshold" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    iwlwifi: mvm: Add a missed beacons threshold

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.7.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 668021bce14f342b93340ef3b45fd24728360907 Mon Sep 17 00:00:00 2001
From: Ilan Peer <ilan.peer at intel.com>
Date: Tue, 24 Dec 2013 22:08:14 +0200
Subject: iwlwifi: mvm: Add a missed beacons threshold

commit 12d423e816c69b0b4457bc047dda9a0a1c1a53c1 upstream.

Instead of always calling ieee80211_beacon_loss() on every missed
beacons notification, call this function only if the number of
consecutive missed beacons from last rx is higher than a predefined
threshold.

Signed-off-by: Ilan Peer <ilan.peer at intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach at intel.com>
Cc: Seth Forshee <seth.forshee at canonical.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c | 25 ++++++++++++++++++++-----
 drivers/net/wireless/iwlwifi/mvm/mvm.h      |  1 +
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
index 1fc0332..07d78ac 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
@@ -1148,10 +1148,18 @@ int iwl_mvm_rx_beacon_notif(struct iwl_mvm *mvm,
 static void iwl_mvm_beacon_loss_iterator(void *_data, u8 *mac,
 					 struct ieee80211_vif *vif)
 {
-	u16 *id = _data;
+	struct iwl_missed_beacons_notif *missed_beacons = _data;
 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);

-	if (mvmvif->id == *id)
+	if (mvmvif->id != (u16)le32_to_cpu(missed_beacons->mac_id))
+		return;
+
+	/*
+	 * TODO: the threshold should be adjusted based on latency conditions,
+	 * and/or in case of a CS flow on one of the other AP vifs.
+	 */
+	if (le32_to_cpu(missed_beacons->consec_missed_beacons_since_last_rx) >
+	     IWL_MVM_MISSED_BEACONS_THRESHOLD)
 		ieee80211_beacon_loss(vif);
 }

@@ -1160,12 +1168,19 @@ int iwl_mvm_rx_missed_beacons_notif(struct iwl_mvm *mvm,
 				    struct iwl_device_cmd *cmd)
 {
 	struct iwl_rx_packet *pkt = rxb_addr(rxb);
-	struct iwl_missed_beacons_notif *missed_beacons = (void *)pkt->data;
-	u16 id = (u16)le32_to_cpu(missed_beacons->mac_id);
+	struct iwl_missed_beacons_notif *mb = (void *)pkt->data;
+
+	IWL_DEBUG_INFO(mvm,
+		       "missed bcn mac_id=%u, consecutive=%u (%u, %u, %u)\n",
+		       le32_to_cpu(mb->mac_id),
+		       le32_to_cpu(mb->consec_missed_beacons),
+		       le32_to_cpu(mb->consec_missed_beacons_since_last_rx),
+		       le32_to_cpu(mb->num_recvd_beacons),
+		       le32_to_cpu(mb->num_expected_beacons));

 	ieee80211_iterate_active_interfaces_atomic(mvm->hw,
 						   IEEE80211_IFACE_ITER_NORMAL,
 						   iwl_mvm_beacon_loss_iterator,
-						   &id);
+						   mb);
 	return 0;
 }
diff --git a/drivers/net/wireless/iwlwifi/mvm/mvm.h b/drivers/net/wireless/iwlwifi/mvm/mvm.h
index 17f1096..0f0de23 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mvm.h
+++ b/drivers/net/wireless/iwlwifi/mvm/mvm.h
@@ -81,6 +81,7 @@
 #define IWL_MVM_MAX_ADDRESSES		5
 /* RSSI offset for WkP */
 #define IWL_RSSI_OFFSET 50
+#define IWL_MVM_MISSED_BEACONS_THRESHOLD 8

 enum iwl_mvm_tx_fifo {
 	IWL_MVM_TX_FIFO_BK = 0,
--
1.9.1