+ watchdog-hardlockup-style-changes-to-watchdog_hardlockup_check-is_hardlockup.patch added to mm-nonmm-unstable branch

+ watchdog-hardlockup-style-changes-to-watchdog_hardlockup_check-is_hardlockup.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: watchdog/hardlockup: style changes to watchdog_hardlockup_check() / is_hardlockup()
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     watchdog-hardlockup-style-changes-to-watchdog_hardlockup_check-is_hardlockup.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/watchdog-hardlockup-style-changes-to-watchdog_hardlockup_check-is_hardlockup.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: Douglas Anderson <dianders@chromium.org>
Subject: watchdog/hardlockup: style changes to watchdog_hardlockup_check() / is_hardlockup()
Date: Fri, 19 May 2023 10:18:33 -0700

These are tiny style changes:
- Add a blank line before a "return".
- Renames two globals to use the "watchdog_hardlockup" prefix.
- Store processor id in "unsigned int" rather than "int".
- Minor comment rewording.
- Use "else" rather than extra returns since it seemed more symmetric.

Link: https://lkml.kernel.org/r/20230519101840.v5.9.I818492c326b632560b09f20d2608455ecf9d3650@changeid
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Colin Cross <ccross@android.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masayoshi Mizuma <msys.mizuma@gmail.com>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Sumit Garg <sumit.garg@linaro.org>
Cc: Tzung-Bi Shih <tzungbi@chromium.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/watchdog.c |   32 +++++++++++++++-----------------
 1 file changed, 15 insertions(+), 17 deletions(-)

--- a/kernel/watchdog.c~watchdog-hardlockup-style-changes-to-watchdog_hardlockup_check-is_hardlockup
+++ a/kernel/watchdog.c
@@ -89,8 +89,8 @@ __setup("nmi_watchdog=", hardlockup_pani
 
 static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts);
 static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts_saved);
-static DEFINE_PER_CPU(bool, hard_watchdog_warn);
-static unsigned long hardlockup_allcpu_dumped;
+static DEFINE_PER_CPU(bool, watchdog_hardlockup_warned);
+static unsigned long watchdog_hardlockup_all_cpu_dumped;
 
 static bool is_hardlockup(void)
 {
@@ -100,6 +100,7 @@ static bool is_hardlockup(void)
 		return true;
 
 	__this_cpu_write(hrtimer_interrupts_saved, hrint);
+
 	return false;
 }
 
@@ -110,21 +111,20 @@ static void watchdog_hardlockup_kick(voi
 
 void watchdog_hardlockup_check(struct pt_regs *regs)
 {
-	/* check for a hardlockup
-	 * This is done by making sure our timer interrupt
-	 * is incrementing.  The timer interrupt should have
-	 * fired multiple times before we overflow'd.  If it hasn't
+	/*
+	 * Check for a hardlockup by making sure the CPU's timer
+	 * interrupt is incrementing. The timer interrupt should have
+	 * fired multiple times before we overflow'd. If it hasn't
 	 * then this is a good indication the cpu is stuck
 	 */
 	if (is_hardlockup()) {
-		int this_cpu = smp_processor_id();
+		unsigned int this_cpu = smp_processor_id();
 
-		/* only print hardlockups once */
-		if (__this_cpu_read(hard_watchdog_warn) == true)
+		/* Only print hardlockups once. */
+		if (__this_cpu_read(watchdog_hardlockup_warned))
 			return;
 
-		pr_emerg("Watchdog detected hard LOCKUP on cpu %d\n",
-			 this_cpu);
+		pr_emerg("Watchdog detected hard LOCKUP on cpu %d\n", this_cpu);
 		print_modules();
 		print_irqtrace_events(current);
 		if (regs)
@@ -137,18 +137,16 @@ void watchdog_hardlockup_check(struct pt
 		 * generating interleaving traces
 		 */
 		if (sysctl_hardlockup_all_cpu_backtrace &&
-				!test_and_set_bit(0, &hardlockup_allcpu_dumped))
+		    !test_and_set_bit(0, &watchdog_hardlockup_all_cpu_dumped))
 			trigger_allbutself_cpu_backtrace();
 
 		if (hardlockup_panic)
 			nmi_panic(regs, "Hard LOCKUP");
 
-		__this_cpu_write(hard_watchdog_warn, true);
-		return;
+		__this_cpu_write(watchdog_hardlockup_warned, true);
+	} else {
+		__this_cpu_write(watchdog_hardlockup_warned, false);
 	}
-
-	__this_cpu_write(hard_watchdog_warn, false);
-	return;
 }
 
 #else /* CONFIG_HARDLOCKUP_DETECTOR_PERF */
_

Patches currently in -mm which might be from dianders@chromium.org are

migrate_pages-avoid-blocking-for-io-in-migrate_sync_light.patch
watchdog-perf-define-dummy-watchdog_update_hrtimer_threshold-on-correct-config.patch
watchdog-perf-more-properly-prevent-false-positives-with-turbo-modes.patch
watchdog-hardlockup-add-comments-to-touch_nmi_watchdog.patch
watchdog-perf-rename-watchdog_hldc-to-watchdog_perfc.patch
watchdog-hardlockup-move-perf-hardlockup-checking-panic-to-common-watchdogc.patch
watchdog-hardlockup-style-changes-to-watchdog_hardlockup_check-is_hardlockup.patch
watchdog-hardlockup-add-a-cpu-param-to-watchdog_hardlockup_check.patch
watchdog-hardlockup-move-perf-hardlockup-watchdog-petting-to-watchdogc.patch
watchdog-hardlockup-rename-some-nmi-watchdog-constants-function.patch
watchdog-hardlockup-have-the-perf-hardlockup-use-__weak-functions-more-cleanly.patch
watchdog-hardlockup-detect-hard-lockups-using-secondary-buddy-cpus.patch
watchdog-perf-add-a-weak-function-for-an-arch-to-detect-if-perf-can-use-nmis.patch
arm64-enable-perf-events-based-hard-lockup-detector.patch