Re: [PATCH v2 03/14] arm: arm64: Don't use disable_nonboot_cpus()

Qais Yousef
2020-01-21T16:58:15Z

On 01/21/20 16:53, Russell King - ARM Linux admin wrote:
> On Tue, Jan 21, 2020 at 04:50:31PM +0000, Qais Yousef wrote:
> > On 11/25/19 11:27, Qais Yousef wrote:
> > > disable_nonboot_cpus() is not safe to use when doing machine_down(),
> > > because it relies on freeze_secondary_cpus() which in return is
> > > a suspend/resume related freeze and could abort if the logic detects any
> > > pending activities that can prevent finishing the offlining process.
> > >
> > > Beside disable_nonboot_cpus() is dependent on CONFIG_PM_SLEEP_SMP which
> > > is an othogonal config to rely on to ensure this function works
> > > correctly.
> > >
> > > Signed-off-by: Qais Yousef <qais.yousef@arm.com>
> > > CC: Russell King <linux@armlinux.org.uk>
> > > CC: Catalin Marinas <catalin.marinas@arm.com>
> > > CC: Will Deacon <will@kernel.org>
> > > CC: linux-arm-kernel@lists.infradead.org
> > > CC: linux-kernel@vger.kernel.org
> > > ---
> >
> > Ping :)
> >
> > I'm missing ACKs on this patch and patch 4 for arm64. Hopefully none should be
> > controversial.
>
> ARM and ARM64 are maintained separately, so you can't submit a single
> patch covering both. Sorry.

Sure I'd be happy to split.

It was just a single line change and I expected Thomas to pick the whole series
up, so I didn't think there'd be an issue in combining them up since they're
identical.

Do I take it you have no objection to the code change itself and just would
like to see this split up?

Thanks

--
Qais Yousef

>
> >
> > Thanks!
> >
> > --
> > Qais Yousef
> >
> > > arch/arm/kernel/reboot.c | 4 ++--
> > > arch/arm64/kernel/process.c | 4 ++--
> > > 2 files changed, 4 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/arch/arm/kernel/reboot.c b/arch/arm/kernel/reboot.c
> > > index bb18ed0539f4..58ad1a70f770 100644
> > > --- a/arch/arm/kernel/reboot.c
> > > +++ b/arch/arm/kernel/reboot.c
> > > @@ -88,11 +88,11 @@ void soft_restart(unsigned long addr)
> > > * to execute e.g. a RAM-based pin loop is not sufficient. This allows the
> > > * kexec'd kernel to use any and all RAM as it sees fit, without having to
> > > * avoid any code or data used by any SW CPU pin loop. The CPU hotplug
> > > - * functionality embodied in disable_nonboot_cpus() to achieve this.
> > > + * functionality embodied in smp_shutdown_nonboot_cpus() to achieve this.
> > > */
> > > void machine_shutdown(void)
> > > {
> > > - disable_nonboot_cpus();
> > > + smp_shutdown_nonboot_cpus(0);
> > > }
> > >
> > > /*
> > > diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
> > > index 71f788cd2b18..3bcc9bfc581e 100644
> > > --- a/arch/arm64/kernel/process.c
> > > +++ b/arch/arm64/kernel/process.c
> > > @@ -141,11 +141,11 @@ void arch_cpu_idle_dead(void)
> > > * to execute e.g. a RAM-based pin loop is not sufficient. This allows the
> > > * kexec'd kernel to use any and all RAM as it sees fit, without having to
> > > * avoid any code or data used by any SW CPU pin loop. The CPU hotplug
> > > - * functionality embodied in disable_nonboot_cpus() to achieve this.
> > > + * functionality embodied in smpt_shutdown_nonboot_cpus() to achieve this.
> > > */
> > > void machine_shutdown(void)
> > > {
> > > - disable_nonboot_cpus();
> > > + smp_shutdown_nonboot_cpus(0);
> > > }
> > >
> > > /*
> > > --
> > > 2.17.1
> > >
> >
>
> --
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
> FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
> According to speedtest.net: 11.9Mbps down 500kbps up