Re: [PATCHv3 2/3] arm64: entry: refactor EL1 interrupt entry logic

From: Pingfan Liu
Date: Thu Sep 30 2021 - 22:27:47 EST


On Thu, Sep 30, 2021 at 03:00:59PM +0100, Mark Rutland wrote:
> On Thu, Sep 30, 2021 at 09:17:07PM +0800, Pingfan Liu wrote:
> > From: Mark Rutland <mark.rutland@xxxxxxx>
> >
> > Currently we distinguish IRQ and definitely-PNMI at entry/exit time
> > via the enter_el1_irq_or_nmi() and enter_el1_irq_or_nmi() helpers. In
> > subsequent patches we'll need to handle the two cases more distinctly
> > in the body of the exception handler.
> >
> > To make this possible, this patch refactors el1_interrupt to be a
> > top-level dispatcher to separate handlers for the IRQ and PNMI cases,
> > removing the need for the enter_el1_irq_or_nmi() and
> > exit_el1_irq_or_nmi() helpers.
> >
> > Note that since arm64_enter_nmi() calls __nmi_enter(), which
> > increments the preemt_count, we could never preempt when handling a
> > PNMI. We now only check for preemption in the IRQ case, which makes
> > this clearer.
> >
> > There should be no functional change as a result of this patch.
> >
> > Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
> > Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxx>
> > Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> > Cc: Will Deacon <will@xxxxxxxxxx>
> > Cc: Marc Zyngier <maz@xxxxxxxxxx>
> > Cc: Joey Gouly <joey.gouly@xxxxxxx>
> > Cc: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
> > Cc: Julien Thierry <julien.thierry@xxxxxxx>
> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > Cc: Yuichi Ito <ito-yuichi@xxxxxxxxxxx>
> > Cc: Pingfan Liu <kernelfans@xxxxxxxxx>
> > Cc: linux-kernel@xxxxxxxxxxxxxxx
> > To: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
>
> As a heads-up, you need to add your Signed-off-by tag when you post
> patches from other people, even if you make no changes. See:
>
> https://www.kernel.org/doc/html/v5.14/process/submitting-patches.html#sign-your-work-the-developer-s-certificate-of-origin
>
Oh, thanks and I realize it is a serious license issue.

> Other than that, this looks fine to me.
>
Thank you very much.


Regards,

Pingfan