Re: [PATCH v9 00/12] Support PPTT for ARM64

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Will Deacon <will.deacon@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Jeremy Linton <jeremy.linton@arm.com>,
	ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
	Mark Rutland <Mark.Rutland@arm.com>,
	austinwc@codeaurora.org, tnowicki@caviumnetworks.com,
	Palmer Dabbelt <palmer@sifive.com>,
	linux-riscv@lists.infradead.org, Morten.Rasmussen@arm.com,
	vkilari@codeaurora.org,
	Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>,
	jhugo@codeaurora.org, Al Stone <ahs3@redhat.com>,
	Len Brown <lenb@kernel.org>, John Garry <john.garry@huawei.com>,
	wangxiongfeng2@huawei.com,
	Dietmar Eggemann <Dietmar.Eggemann@arm.com>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	Ard Biesheuvel <ard.biesheuvel@linaro.org>,
	Greg KH <gregkh@linuxfoundation.org>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Hanjun Guo <hanjun.guo@linaro.org>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>
Subject: Re: [PATCH v9 00/12] Support PPTT for ARM64
Date: Tue, 29 May 2018 17:51:29 +0200	[thread overview]
Message-ID: <CAMuHMdU0yET6+-FfS8e9HJdKB7h0gDn7kzWGpJZV=UiWn5fLkA@mail.gmail.com> (raw)
In-Reply-To: <20180529150823.GD17159@arm.com>

Hi Will,

On Tue, May 29, 2018 at 5:08 PM, Will Deacon <will.deacon@arm.com> wrote:
> On Tue, May 29, 2018 at 02:18:40PM +0100, Sudeep Holla wrote:
>> On 29/05/18 12:56, Geert Uytterhoeven wrote:
>> > On Tue, May 29, 2018 at 1:14 PM, Sudeep Holla <sudeep.holla@arm.com> wrote:
>> >> On 29/05/18 11:48, Geert Uytterhoeven wrote:
>> >>> System supend still works fine on systems with big cores only:
>> >>>
>> >>>     R-Car H3 ES1.0 (4xCA57 (4xCA53 disabled in firmware))
>> >>>     R-Car M3-N (2xCA57)
>> >>>
>> >>> Reverting this commit fixes the issue for me.
>> >>
>> >> I can't find anything that relates to system suspend in these patches
>> >> unless they are messing with something during CPU hot plug-in back
>> >> during resume.
>> >
>> > It's only the last patch that introduces the breakage.
>> >
>>
>> As specified in the commit log, it won't change any behavior for DT
>> systems if it's non-NUMA or single node system. So I am still wondering
>> what could trigger this regression.
>
> I wonder if we're somehow giving an uninitialised/invalid NUMA configuration
> to the scheduler, although I can't see how this would happen.
>
> Geert -- if you enable CONFIG_DEBUG_PER_CPU_MAPS=y and apply the diff below
> do you see anything shouting in dmesg?

Thanks, but unfortunately it doesn't help.
I added some debug code to print cpumask, but so far I don't see anything
suspicious.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds