watchdog/hardlockup: style changes to watchdog_hardlockup_check() / is_hardlockup()

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 <[email protected]>
Signed-off-by: Douglas Anderson <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Chen-Yu Tsai <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Colin Cross <[email protected]>
Cc: Daniel Thompson <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Lecopzer Chen <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Masayoshi Mizuma <[email protected]>
Cc: Matthias Kaehlcke <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Pingfan Liu <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: "Ravi V. Shankar" <[email protected]>
Cc: Ricardo Neri <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Stephen Boyd <[email protected]>
Cc: Sumit Garg <[email protected]>
Cc: Tzung-Bi Shih <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

1 files changed, 15 insertions, 17 deletions

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 12ce37d76e7d..169e5dffbc00 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -89,8 +89,8 @@ __setup("nmi_watchdog=", hardlockup_panic_setup);
 
 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(void)
 
 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_regs *regs)
 		 * 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 */