Re: Bug 119151 - [regression] ath10k no longer authenitcates and freezes system

From: "Manoharan, Rajkumar" <rmanohar@qti.qualcomm.com>
To: Ben Greear <greearb@candelatech.com>,
	"Valo, Kalle" <kvalo@qca.qualcomm.com>,
	"ath10k@lists.infradead.org" <ath10k@lists.infradead.org>,
	Rajkumar Manoharan <rmanohar@codeaurora.org>
Cc: "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>,
	"mike@fireburn.co.uk" <mike@fireburn.co.uk>
Subject: Re: Bug 119151 - [regression] ath10k no longer authenitcates and freezes system
Date: Thu, 2 Jun 2016 17:03:46 +0000	[thread overview]
Message-ID: <1464887026467.72937@qti.qualcomm.com> (raw)
In-Reply-To: <57504F05.3040200@candelatech.com>

On Thursday, June 2, 2016 8:51 PM, Ben Greear <greearb@candelatech.com> wrote:
> On 06/02/2016 07:24 AM, Valo, Kalle wrote:
>> Kalle Valo <kvalo@qca.qualcomm.com> writes:
>>
>>> there's a regression in ath10k:
>>>
>>> https://bugzilla.kernel.org/show_bug.cgi?id=119151
>>>
>>> Reporter bisected it to this:
>>>
>>> 5c86d97bcc1d42ce7f75685a61be4dad34ee8183 is the first bad commit
>>> commit 5c86d97bcc1d42ce7f75685a61be4dad34ee8183
>>> Author: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
>>> Date:   Tue Mar 22 17:22:19 2016 +0530
>>>
>>> ath10k: combine txrx and replenish task
>>>
>>> Since tx completion and rx indication processing are moved out
>>> of txrx tasklet and rx ring lock contention also removed from txrx
>>> for rx_ind messages, it would be efficient to combine both replenish
>>> and txrx tasks. Refill threshold is adjusted for both AP135 and AP148
>>> (low and high end systems). With this adjustment in AP135, TCP DL is
>>> improved from 603 Mbps to 620 Mbps and UDP DL is improved from 758 Mbps
>>> to 803 Mbps. Also no watchdog are observed on UDP BiDi.
>>>
>>> Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
>>> Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
>>
>> Adding Mike, the bug reporter.
>
Mike,

Sorry for the regression. Since the patch combines both txrx and replenish tasklet,
it is validated in low end embedded devices like AP135 (single core 720 MHz MIPS processor).

It seems yours is octa core processor.  So CPU is not bottleneck here. Need your help to fix this issue asap. 
Can you please try reducing rx refill threshold as below.

diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h
index 2aa407160859..d35d3d48ae6c 100644
--- a/drivers/net/wireless/ath/ath10k/htt.h
+++ b/drivers/net/wireless/ath/ath10k/htt.h
@@ -1734,7 +1734,7 @@ struct htt_rx_desc {
 
 /* Refill a bunch of RX buffers for each refill round so that FW/HW can handle
  * aggregated traffic more nicely. */
-#define ATH10K_HTT_MAX_NUM_REFILL 100
+#define ATH10K_HTT_MAX_NUM_REFILL 16

>From your log attachment from bug report, I found few timed out messages.
May 30 21:09:26 axion kernel: wlan0: deauthenticating from a0:63:91:a7:3c:9f by local choice (Reason: 3=DEAUTH_LEAVING)
May 30 21:09:32 axion kernel: ath10k_pci 0000:3c:00.0: failed to flush transmit queue (skip 0 ar-state 1): 0
May 30 21:09:35 axion kernel: ath10k_pci 0000:3c:00.0: failed to delete peer a0:63:91:a7:3c:9f for vdev 0: -110
May 30 21:09:35 axion kernel: ath10k_pci 0000:3c:00.0: found sta peer a0:63:91:a7:3c:9f entry on vdev 0 after it was supposed

Try disabling pci power save for qca6174 as below.

diff --git a/drivers/net/wireless/ath/ath10k/pci.c b/drivers/net/wireless/ath/ath10k/pci.c
index 852f2c18cd11..5e3ba37a8c6a 100644
--- a/drivers/net/wireless/ath/ath10k/pci.c
+++ b/drivers/net/wireless/ath/ath10k/pci.c
@@ -2979,7 +2979,7 @@ static int ath10k_pci_probe(struct pci_dev *pdev,
        case QCA6164_2_1_DEVICE_ID:
        case QCA6174_2_1_DEVICE_ID:
                hw_rev = ATH10K_HW_QCA6174;
-               pci_ps = true;
+               pci_ps = false;
                pci_soft_reset = ath10k_pci_warm_reset;
                pci_hard_reset = ath10k_pci_qca6174_chip_reset;

>
> I found a lot of problems with this code as well, and the 5 patches
> starting from the URL below fixed the issues for me.
> 
Ben,

Can you please explain the sort of issues you have observed with this change?

-Rajkumar
