linux-kernel - Re: Flood of logitech-hidpp-device messages in v6.7

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Message-ID: <489d6c71-73eb-4605-8293-5cfea385cf08@redhat.com>
Date: Mon, 29 Jan 2024 17:08:56 +0100
From: Hans de Goede <hdegoede@...hat.com>
To: Oleksandr Natalenko <oleksandr@...alenko.name>,
 linux-kernel@...r.kernel.org
Cc: linux-input@...r.kernel.org, Filipe Laíns
 <lains@...eup.net>, Bastien Nocera <hadess@...ess.net>,
 Jiri Kosina <jikos@...nel.org>,
 Benjamin Tissoires <benjamin.tissoires@...hat.com>
Subject: Re: Flood of logitech-hidpp-device messages in v6.7

Hi,

On 1/29/24 16:58, Oleksandr Natalenko wrote:
> Hello.
> 
> On úterý 9. ledna 2024 12:58:10 CET Hans de Goede wrote:
>> Hi Oleksandr,
>>
>> On 1/9/24 12:45, Oleksandr Natalenko wrote:
>>> Hello Hans et al.
>>>
>>> Starting from v6.7 release I get the following messages repeating in `dmesg` regularly:
>>>
>>> ```
>>> Jan 09 10:05:06 spock kernel: logitech-hidpp-device 0003:046D:4051.0006: Disconnected
>>> Jan 09 10:07:15 spock kernel: logitech-hidpp-device 0003:046D:408A.0005: Disconnected
>>> Jan 09 10:16:51 spock kernel: logitech-hidpp-device 0003:046D:4051.0006: HID++ 4.5 device connected.
>>> Jan 09 10:16:55 spock kernel: logitech-hidpp-device 0003:046D:408A.0005: HID++ 4.5 device connected.
>>> Jan 09 10:16:55 spock kernel: logitech-hidpp-device 0003:046D:408A.0005: HID++ 4.5 device connected.
>>> Jan 09 10:36:31 spock kernel: logitech-hidpp-device 0003:046D:4051.0006: Disconnected
>>> Jan 09 10:37:07 spock kernel: logitech-hidpp-device 0003:046D:4051.0006: HID++ 4.5 device connected.
>>> Jan 09 10:46:21 spock kernel: logitech-hidpp-device 0003:046D:4051.0006: Disconnected
>>> Jan 09 10:48:23 spock kernel: logitech-hidpp-device 0003:046D:408A.0005: Disconnected
>>> Jan 09 11:12:27 spock kernel: logitech-hidpp-device 0003:046D:4051.0006: HID++ 4.5 device connected.
>>> Jan 09 11:12:47 spock kernel: logitech-hidpp-device 0003:046D:408A.0005: HID++ 4.5 device connected.
>>> Jan 09 11:12:47 spock kernel: logitech-hidpp-device 0003:046D:408A.0005: HID++ 4.5 device connected.
>>> Jan 09 11:38:32 spock kernel: logitech-hidpp-device 0003:046D:4051.0006: Disconnected
>>> Jan 09 11:43:32 spock kernel: logitech-hidpp-device 0003:046D:408A.0005: Disconnected
>>> Jan 09 11:45:10 spock kernel: logitech-hidpp-device 0003:046D:4051.0006: HID++ 4.5 device connected.
>>> Jan 09 11:45:11 spock kernel: logitech-hidpp-device 0003:046D:408A.0005: HID++ 4.5 device connected.
>>> Jan 09 11:45:11 spock kernel: logitech-hidpp-device 0003:046D:408A.0005: HID++ 4.5 device connected.
>>> Jan 09 12:31:48 spock kernel: logitech-hidpp-device 0003:046D:4051.0006: Disconnected
>>> Jan 09 12:33:21 spock kernel: logitech-hidpp-device 0003:046D:4051.0006: HID++ 4.5 device connected.
>>> ```
>>>
>>> I've got the following hardware:
>>>
>>> * Bus 006 Device 004: ID 046d:c52b Logitech, Inc. Unifying Receiver
>>> * Logitech MX Keys
>>> * Logitech M510v2
>>>
>>> With v6.6 I do not get those messages.
>>>
>>> I think this is related to 680ee411a98e ("HID: logitech-hidpp: Fix connect event race").
>>>
>>> My speculation is that some of the devices enter powersaving state after being idle for some time (5 mins?), and then wake up and reconnect once I touch either keyboard or mouse. I should highlight that everything works just fine, it is the flood of messages that worries me.
>>>
>>> Is it expected?
>>
>> Yes this is expected, looking at your logs I see about 10 messages per
>> hour which IMHO is not that bad.
>>
>> I guess we could change things to track we have logged the connect
>> message once and if yes then log future connect messages (and all
>> disconnect messages) at debug level.
> 
> How granular such a tracking should be? Per-`struct hidpp_device`?

Yes per struct hidpp_device we want to log the connect message once
per device since it gives info which might be useful for troubleshooting.

> Should there be something like `hid_info_once_then_dbg()` macro, or open-code it in each place instead?

Since we want something like e.g. a "first_connect" (initialized
to true if you use that name) flag per struct hidpp_device this needs
to be open coded.

Regards,

Hans