linux-kernel - Re: [RFT][PATCH v4 0/2] PM: sleep: Handle async suppliers like parents and async consumers like children

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <0412561d-6ed3-4823-b510-8600fd4fd1fa@amd.com>
Date: Fri, 27 Jun 2025 09:01:30 -0500
From: Mario Limonciello <mario.limonciello@....com>
To: "Rafael J. Wysocki" <rafael@...nel.org>
Cc: Ulf Hansson <ulf.hansson@...aro.org>,
 "Rafael J. Wysocki" <rjw@...ysocki.net>, Linux PM
 <linux-pm@...r.kernel.org>, LKML <linux-kernel@...r.kernel.org>,
 Chris Bainbridge <chris.bainbridge@...il.com>,
 Saravana Kannan <saravanak@...gle.com>, Sudeep Holla <sudeep.holla@....com>
Subject: Re: [RFT][PATCH v4 0/2] PM: sleep: Handle async suppliers like
 parents and async consumers like children

On 6/27/2025 5:40 AM, Rafael J. Wysocki wrote:
> On Fri, Jun 27, 2025 at 12:28 AM Mario Limonciello
> <mario.limonciello@....com> wrote:
>>
>> On 6/26/2025 4:46 AM, Ulf Hansson wrote:
>>> On Mon, 23 Jun 2025 at 14:55, Rafael J. Wysocki <rjw@...ysocki.net> wrote:
>>>>
>>>> Hi Everyone,
>>>>
>>>> These two patches complement the recently made PM core changes related to
>>>> the async suspend and resume of devices.  They should apply on top of
>>>> 6.16-rc3.
>>>>
>>>> They were sent along with the other changes mentioned above:
>>>>
>>>> https://lore.kernel.org/linux-pm/2229735.Mh6RI2rZIc@rjwysocki.net/
>>>> https://lore.kernel.org/linux-pm/2651185.Lt9SDvczpP@rjwysocki.net/
>>>>
>>>> (and this is v4 because they have been rebased in the meantime), but they don't
>>>> make any difference on my test-bed x86 systems, so I'd appreciate a confirmation
>>>> that they are actually needed on ARM (or another architecture using DT).
>>>>
>>>> Thanks!
>>>
>>> Hi Rafael,
>>>
>>> I haven't yet got the time to test these, but the code looks good to
>>> me, so feel free to add for the series:
>>>
>>> Reviewed-by: Ulf Hansson <ulf.hansson@...aro.org>
>>>
>>> Kind regards
>>> Uffe
>>
>> I passed this series to some internal guys to test on a wide variety of
>> AMD x86 hardware.  The initial testing looks good.
>> Will keep you apprised if anything pops up.
> 
> Thanks!
> 
> It would also help if you could check whether or not there is any
> measurable performance (that is, system suspend and resume time)
> difference between "before" and "after".

Sure thing.

Just to make sure we have an aligned measurement methodology:

I asked them to do this both with and without the patches.

* set /sys/power/pm_debug_messages before running and then capture all 
the timing prints.
* add up all suspend events and get a total
* add up all resume events and get a total
* repeat 5 times
* calculate averages for the 5 runs