All of lore.kernel.org
 help / color / mirror / Atom feed
From: Douglas Anderson <dianders@chromium.org>
To: Mark Rutland <mark.rutland@arm.com>,
	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>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>,
	linux-arm-kernel@lists.infradead.org,
	linux-perf-users@vger.kernel.org,
	Peter Zijlstra <peterz@infradead.org>,
	kgdb-bugreport@lists.sourceforge.net, ito-yuichi@fujitsu.com,
	Stephen Boyd <swboyd@chromium.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Chen-Yu Tsai <wens@csie.org>, Ard Biesheuvel <ardb@kernel.org>,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Masayoshi Mizuma <msys.mizuma@gmail.com>,
	Douglas Anderson <dianders@chromium.org>,
	D Scott Phillips <scott@os.amperecomputing.com>,
	Ingo Molnar <mingo@kernel.org>,
	Josh Poimboeuf <jpoimboe@kernel.org>,
	Valentin Schneider <vschneid@redhat.com>,
	linux-kernel@vger.kernel.org
Subject: [PATCH v10 5/6] arm64: smp: IPI_CPU_STOP and IPI_CPU_CRASH_STOP should try for NMI
Date: Tue, 22 Aug 2023 14:27:00 -0700	[thread overview]
Message-ID: <20230822142644.v10.5.Ifadbfd45b22c52edcb499034dd4783d096343260@changeid> (raw)
In-Reply-To: <20230822212927.249645-1-dianders@chromium.org>

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>
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.

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 15b66dc1391b..c51d54019f5f 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.rc1.204.g551eb34607-goog


WARNING: multiple messages have this Message-ID (diff)
From: Douglas Anderson <dianders@chromium.org>
To: Mark Rutland <mark.rutland@arm.com>,
	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>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>,
	linux-arm-kernel@lists.infradead.org,
	linux-perf-users@vger.kernel.org,
	Peter Zijlstra <peterz@infradead.org>,
	kgdb-bugreport@lists.sourceforge.net, ito-yuichi@fujitsu.com,
	Stephen Boyd <swboyd@chromium.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Chen-Yu Tsai <wens@csie.org>, Ard Biesheuvel <ardb@kernel.org>,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Masayoshi Mizuma <msys.mizuma@gmail.com>,
	Douglas Anderson <dianders@chromium.org>,
	D Scott Phillips <scott@os.amperecomputing.com>,
	Ingo Molnar <mingo@kernel.org>,
	Josh Poimboeuf <jpoimboe@kernel.org>,
	Valentin Schneider <vschneid@redhat.com>,
	linux-kernel@vger.kernel.org
Subject: [PATCH v10 5/6] arm64: smp: IPI_CPU_STOP and IPI_CPU_CRASH_STOP should try for NMI
Date: Tue, 22 Aug 2023 14:27:00 -0700	[thread overview]
Message-ID: <20230822142644.v10.5.Ifadbfd45b22c52edcb499034dd4783d096343260@changeid> (raw)
In-Reply-To: <20230822212927.249645-1-dianders@chromium.org>

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>
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.

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 15b66dc1391b..c51d54019f5f 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.rc1.204.g551eb34607-goog


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  parent reply	other threads:[~2023-08-22 21:31 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-08-22 21:26 [PATCH v10 0/6] arm64: Add IPI for backtraces / kgdb; try to use NMI for some IPIs Douglas Anderson
2023-08-22 21:26 ` Douglas Anderson
2023-08-22 21:26 ` [PATCH v10 1/6] irqchip/gic-v3: Enable support for SGIs to act as NMIs Douglas Anderson
2023-08-22 21:26   ` Douglas Anderson
2023-08-22 21:26 ` [PATCH v10 2/6] arm64: idle: Tag the arm64 idle functions as __cpuidle Douglas Anderson
2023-08-22 21:26   ` Douglas Anderson
2023-08-22 23:14   ` Stephen Boyd
2023-08-22 23:14     ` Stephen Boyd
2023-08-22 21:26 ` [PATCH v10 3/6] arm64: smp: Remove dedicated wakeup IPI Douglas Anderson
2023-08-22 21:26   ` Douglas Anderson
2023-08-22 23:16   ` Stephen Boyd
2023-08-22 23:16     ` Stephen Boyd
2023-08-22 21:26 ` [PATCH v10 4/6] arm64: smp: Add arch support for backtrace using pseudo-NMI Douglas Anderson
2023-08-22 21:26   ` Douglas Anderson
2023-08-22 23:39   ` Stephen Boyd
2023-08-22 23:39     ` Stephen Boyd
2023-08-23 19:58   ` kernel test robot
2023-08-23 19:58     ` kernel test robot
2023-08-22 21:27 ` Douglas Anderson [this message]
2023-08-22 21:27   ` [PATCH v10 5/6] arm64: smp: IPI_CPU_STOP and IPI_CPU_CRASH_STOP should try for NMI Douglas Anderson
2023-08-22 23:41   ` Stephen Boyd
2023-08-22 23:41     ` Stephen Boyd
2023-08-22 21:27 ` [PATCH v10 6/6] arm64: kgdb: Implement kgdb_roundup_cpus() to enable pseudo-NMI roundup Douglas Anderson
2023-08-22 21:27   ` Douglas Anderson
2023-08-22 23:50   ` Stephen Boyd
2023-08-22 23:50     ` Stephen Boyd

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=20230822142644.v10.5.Ifadbfd45b22c52edcb499034dd4783d096343260@changeid \
    --to=dianders@chromium.org \
    --cc=ardb@kernel.org \
    --cc=catalin.marinas@arm.com \
    --cc=daniel.thompson@linaro.org \
    --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=mark.rutland@arm.com \
    --cc=maz@kernel.org \
    --cc=mingo@kernel.org \
    --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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.