Patch "iwlwifi: dvm: drop non VO frames when flushing" has been added to the 3.17-stable tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



This is a note to let you know that I've just added the patch titled

    iwlwifi: dvm: drop non VO frames when flushing

to the 3.17-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     iwlwifi-dvm-drop-non-vo-frames-when-flushing.patch
and it can be found in the queue-3.17 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From a0855054e59b0c5b2b00237fdb5147f7bcc18efb Mon Sep 17 00:00:00 2001
From: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx>
Date: Sun, 5 Oct 2014 09:11:14 +0300
Subject: iwlwifi: dvm: drop non VO frames when flushing

From: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx>

commit a0855054e59b0c5b2b00237fdb5147f7bcc18efb upstream.

When mac80211 wants to ensure that a frame is sent, it calls
the flush() callback. Until now, iwldvm implemented this by
waiting that all the frames are sent (ACKed or timeout).
In case of weak signal, this can take a significant amount
of time, delaying the next connection (in case of roaming).
Many users have reported that the flush would take too long
leading to the following error messages to be printed:

iwlwifi 0000:03:00.0: fail to flush all tx fifo queues Q 2
iwlwifi 0000:03:00.0: Current SW read_ptr 161 write_ptr 201
iwl data: 00000000: 00 00 00 00 00 00 00 00 fe ff 01 00 00 00 00 00
[snip]
iwlwifi 0000:03:00.0: FH TRBs(0) = 0x00000000
[snip]
iwlwifi 0000:03:00.0: Q 0 is active and mapped to fifo 3 ra_tid 0x0000 [9,9]
[snip]

Instead of waiting for these packets, simply drop them. This
significantly improves the responsiveness of the network.
Note that all the queues are flushed, but the VO one. This
is not typically used by the applications and it likely
contains management frames that are useful for connection
or roaming.

This bug is tracked here:
https://bugzilla.kernel.org/show_bug.cgi?id=56581

But it is duplicated in distributions' trackers.
A simple search in Ubuntu's database led to these bugs:

https://bugs.launchpad.net/ubuntu/+source/linux-firmware/+bug/1270808
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1305406
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1356236
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1360597
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1361809

Depends-on: 77be2c54c5bd ("mac80211: add vif to flush call")
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/wireless/iwlwifi/dvm/mac80211.c |   24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

--- a/drivers/net/wireless/iwlwifi/dvm/mac80211.c
+++ b/drivers/net/wireless/iwlwifi/dvm/mac80211.c
@@ -1095,6 +1095,7 @@ static void iwlagn_mac_flush(struct ieee
 			     u32 queues, bool drop)
 {
 	struct iwl_priv *priv = IWL_MAC80211_GET_DVM(hw);
+	u32 scd_queues;
 
 	mutex_lock(&priv->mutex);
 	IWL_DEBUG_MAC80211(priv, "enter\n");
@@ -1108,18 +1109,19 @@ static void iwlagn_mac_flush(struct ieee
 		goto done;
 	}
 
-	/*
-	 * mac80211 will not push any more frames for transmit
-	 * until the flush is completed
-	 */
-	if (drop) {
-		IWL_DEBUG_MAC80211(priv, "send flush command\n");
-		if (iwlagn_txfifo_flush(priv, 0)) {
-			IWL_ERR(priv, "flush request fail\n");
-			goto done;
-		}
+	scd_queues = BIT(priv->cfg->base_params->num_of_queues) - 1;
+	scd_queues &= ~(BIT(IWL_IPAN_CMD_QUEUE_NUM) |
+			BIT(IWL_DEFAULT_CMD_QUEUE_NUM));
+
+	if (vif)
+		scd_queues &= ~BIT(vif->hw_queue[IEEE80211_AC_VO]);
+
+	IWL_DEBUG_TX_QUEUES(priv, "Flushing SCD queues: 0x%x\n", scd_queues);
+	if (iwlagn_txfifo_flush(priv, scd_queues)) {
+		IWL_ERR(priv, "flush request fail\n");
+		goto done;
 	}
-	IWL_DEBUG_MAC80211(priv, "wait transmit/flush all frames\n");
+	IWL_DEBUG_TX_QUEUES(priv, "wait transmit/flush all frames\n");
 	iwl_trans_wait_tx_queue_empty(priv->trans, 0xffffffff);
 done:
 	mutex_unlock(&priv->mutex);


Patches currently in stable-queue which might be from emmanuel.grumbach@xxxxxxxxx are

queue-3.17/iwlwifi-mvm-bt-coex-update-the-mplut-boost-register-value.patch
queue-3.17/revert-iwlwifi-mvm-treat-eapols-like-mgmt-frames-wrt-rate.patch
queue-3.17/iwlwifi-configure-the-ltr.patch
queue-3.17/iwlwifi-dvm-drop-non-vo-frames-when-flushing.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]