From: Mark Rutland <mark.rutland@arm.com>
To: Douglas Anderson <dianders@chromium.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will@kernel.org>, Sumit Garg <sumit.garg@linaro.org>,
Daniel Thompson <daniel.thompson@linaro.org>,
Marc Zyngier <maz@kernel.org>,
linux-arm-kernel@lists.infradead.org,
Masayoshi Mizuma <msys.mizuma@gmail.com>,
"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
Chen-Yu Tsai <wens@csie.org>,
Lecopzer Chen <lecopzer.chen@mediatek.com>,
Tomohiro Misono <misono.tomohiro@fujitsu.com>,
Stephane Eranian <eranian@google.com>,
kgdb-bugreport@lists.sourceforge.net,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
Stephen Boyd <swboyd@chromium.org>,
ito-yuichi@fujitsu.com, linux-perf-users@vger.kernel.org,
Ard Biesheuvel <ardb@kernel.org>,
D Scott Phillips <scott@os.amperecomputing.com>,
Josh Poimboeuf <jpoimboe@kernel.org>,
Valentin Schneider <vschneid@redhat.com>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v12 5/7] arm64: smp: IPI_CPU_STOP and IPI_CPU_CRASH_STOP should try for NMI
Date: Thu, 31 Aug 2023 11:12:34 +0100 [thread overview]
Message-ID: <ZPBnkkDc9GSxrjmC@FVFF77S0Q05N> (raw)
In-Reply-To: <20230830121115.v12.5.Ifadbfd45b22c52edcb499034dd4783d096343260@changeid>
On Wed, Aug 30, 2023 at 12:11:26PM -0700, Douglas Anderson wrote:
> There's no reason why IPI_CPU_STOP and IPI_CPU_CRASH_STOP can't be
> handled as NMI. They are very simple and everything in them is
> NMI-safe. Mark them as things to use NMI for if NMI is available.
>
> Suggested-by: Mark Rutland <mark.rutland@arm.com>
> Reviewed-by: Stephen Boyd <swboyd@chromium.org>
> Reviewed-by: Misono Tomohiro <misono.tomohiro@fujitsu.com>
> Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> ---
> I don't actually have any good way to test/validate this patch. It's
> added to the series at Mark's request.
I've just sent out an LKDTM test that can be used to test this:
http://lore.kernel.org/lkml/20230831101026.3122590-1-mark.rutland@arm.com
So FWIW:
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Mark.
>
> (no changes since v10)
>
> Changes in v10:
> - ("IPI_CPU_STOP and IPI_CPU_CRASH_STOP should try for NMI") new for v10.
>
> arch/arm64/kernel/smp.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
> index 28c904ca499a..800c59cf9b64 100644
> --- a/arch/arm64/kernel/smp.c
> +++ b/arch/arm64/kernel/smp.c
> @@ -946,6 +946,8 @@ static bool ipi_should_be_nmi(enum ipi_msg_type ipi)
> return false;
>
> switch (ipi) {
> + case IPI_CPU_STOP:
> + case IPI_CPU_CRASH_STOP:
> case IPI_CPU_BACKTRACE:
> return true;
> default:
> --
> 2.42.0.283.g2d96d420d3-goog
>
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2023-08-31 10:13 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-30 19:11 [PATCH v12 0/7] arm64: Add IPI for backtraces / kgdb; try to use NMI for some IPIs Douglas Anderson
2023-08-30 19:11 ` [PATCH v12 1/7] irqchip/gic-v3: Enable support for SGIs to act as NMIs Douglas Anderson
2023-08-31 8:53 ` Mark Rutland
2023-08-31 15:31 ` Doug Anderson
2023-08-31 15:45 ` Mark Rutland
2023-08-30 19:11 ` [PATCH v12 2/7] arm64: idle: Tag the arm64 idle functions as __cpuidle Douglas Anderson
2023-08-30 19:11 ` [PATCH v12 3/7] arm64: smp: Remove dedicated wakeup IPI Douglas Anderson
2023-08-30 19:11 ` [PATCH v12 4/7] arm64: smp: Add arch support for backtrace using pseudo-NMI Douglas Anderson
2023-08-30 19:11 ` [PATCH v12 5/7] arm64: smp: IPI_CPU_STOP and IPI_CPU_CRASH_STOP should try for NMI Douglas Anderson
2023-08-31 10:12 ` Mark Rutland [this message]
2023-08-30 19:11 ` [PATCH v12 6/7] arm64: kgdb: Implement kgdb_roundup_cpus() to enable pseudo-NMI roundup Douglas Anderson
2023-08-31 10:14 ` Mark Rutland
2023-08-30 19:11 ` [PATCH v12 7/7] arm64: smp: Mark IPI globals as __ro_after_init Douglas Anderson
2023-08-31 10:15 ` Mark Rutland
2023-08-31 7:08 ` [PATCH v12 0/7] arm64: Add IPI for backtraces / kgdb; try to use NMI for some IPIs Chen-Yu Tsai
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=ZPBnkkDc9GSxrjmC@FVFF77S0Q05N \
--to=mark.rutland@arm.com \
--cc=ardb@kernel.org \
--cc=catalin.marinas@arm.com \
--cc=daniel.thompson@linaro.org \
--cc=dianders@chromium.org \
--cc=eranian@google.com \
--cc=ito-yuichi@fujitsu.com \
--cc=jpoimboe@kernel.org \
--cc=kgdb-bugreport@lists.sourceforge.net \
--cc=lecopzer.chen@mediatek.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=maz@kernel.org \
--cc=misono.tomohiro@fujitsu.com \
--cc=msys.mizuma@gmail.com \
--cc=peterz@infradead.org \
--cc=rafael.j.wysocki@intel.com \
--cc=scott@os.amperecomputing.com \
--cc=sumit.garg@linaro.org \
--cc=swboyd@chromium.org \
--cc=tglx@linutronix.de \
--cc=vschneid@redhat.com \
--cc=wens@csie.org \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox