From: Douglas Anderson Date: Fri, 19 May 2023 17:18:35 +0000 (-0700) Subject: watchdog/hardlockup: move perf hardlockup watchdog petting to watchdog.c X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=ed92e1ef52224c7c9c15fba559448396b059c2ee;p=linux.git watchdog/hardlockup: move perf hardlockup watchdog petting to watchdog.c In preparation for the buddy hardlockup detector, which wants the same petting logic as the current perf hardlockup detector, move the code to watchdog.c. While doing this, rename the global variable to match others nearby. As part of this change we have to change the code to account for the fact that the CPU we're running on might be different than the one we're checking. Currently the code in watchdog.c is guarded by CONFIG_HARDLOCKUP_DETECTOR_PERF, which makes this change seem silly. However, a future patch will change this. Link: https://lkml.kernel.org/r/20230519101840.v5.11.I00dfd6386ee00da25bf26d140559a41339b53e57@changeid Signed-off-by: Douglas Anderson Cc: Andi Kleen Cc: Catalin Marinas Cc: Chen-Yu Tsai Cc: Christophe Leroy Cc: Colin Cross Cc: Daniel Thompson Cc: "David S. Miller" Cc: Guenter Roeck Cc: Ian Rogers Cc: Lecopzer Chen Cc: Marc Zyngier Cc: Mark Rutland Cc: Masayoshi Mizuma Cc: Matthias Kaehlcke Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Petr Mladek Cc: Pingfan Liu Cc: Randy Dunlap Cc: "Ravi V. Shankar" Cc: Ricardo Neri Cc: Stephane Eranian Cc: Stephen Boyd Cc: Sumit Garg Cc: Tzung-Bi Shih Cc: Will Deacon Signed-off-by: Andrew Morton --- diff --git a/include/linux/nmi.h b/include/linux/nmi.h index 521bf2ee6effa..56fdc3de6894f 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -88,7 +88,10 @@ static inline void hardlockup_detector_disable(void) {} #endif #if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF) +void arch_touch_nmi_watchdog(void); void watchdog_hardlockup_check(unsigned int cpu, struct pt_regs *regs); +#elif !defined(CONFIG_HAVE_NMI_WATCHDOG) +static inline void arch_touch_nmi_watchdog(void) { } #endif #if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR) @@ -98,7 +101,6 @@ void watchdog_hardlockup_check(unsigned int cpu, struct pt_regs *regs); #endif #if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF) -extern void arch_touch_nmi_watchdog(void); extern void hardlockup_detector_perf_stop(void); extern void hardlockup_detector_perf_restart(void); extern void hardlockup_detector_perf_disable(void); @@ -113,7 +115,6 @@ static inline void hardlockup_detector_perf_enable(void) { } static inline void hardlockup_detector_perf_cleanup(void) { } # if !defined(CONFIG_HAVE_NMI_WATCHDOG) static inline int hardlockup_detector_perf_init(void) { return -ENODEV; } -static inline void arch_touch_nmi_watchdog(void) {} # else static inline int hardlockup_detector_perf_init(void) { return 0; } # endif diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 2552e224f76ab..64d7d2a0a7dfe 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -90,8 +90,22 @@ __setup("nmi_watchdog=", hardlockup_panic_setup); static DEFINE_PER_CPU(atomic_t, hrtimer_interrupts); static DEFINE_PER_CPU(int, hrtimer_interrupts_saved); static DEFINE_PER_CPU(bool, watchdog_hardlockup_warned); +static DEFINE_PER_CPU(bool, watchdog_hardlockup_touched); static unsigned long watchdog_hardlockup_all_cpu_dumped; +notrace void arch_touch_nmi_watchdog(void) +{ + /* + * Using __raw here because some code paths have + * preemption enabled. If preemption is enabled + * then interrupts should be enabled too, in which + * case we shouldn't have to worry about the watchdog + * going off. + */ + raw_cpu_write(watchdog_hardlockup_touched, true); +} +EXPORT_SYMBOL(arch_touch_nmi_watchdog); + static bool is_hardlockup(unsigned int cpu) { int hrint = atomic_read(&per_cpu(hrtimer_interrupts, cpu)); @@ -116,6 +130,11 @@ static void watchdog_hardlockup_kick(void) void watchdog_hardlockup_check(unsigned int cpu, struct pt_regs *regs) { + if (per_cpu(watchdog_hardlockup_touched, cpu)) { + per_cpu(watchdog_hardlockup_touched, cpu) = false; + return; + } + /* * Check for a hardlockup by making sure the CPU's timer * interrupt is incrementing. The timer interrupt should have diff --git a/kernel/watchdog_perf.c b/kernel/watchdog_perf.c index 4e60e80235151..547917ebd5d39 100644 --- a/kernel/watchdog_perf.c +++ b/kernel/watchdog_perf.c @@ -20,26 +20,12 @@ #include #include -static DEFINE_PER_CPU(bool, watchdog_nmi_touch); static DEFINE_PER_CPU(struct perf_event *, watchdog_ev); static DEFINE_PER_CPU(struct perf_event *, dead_event); static struct cpumask dead_events_mask; static atomic_t watchdog_cpus = ATOMIC_INIT(0); -notrace void arch_touch_nmi_watchdog(void) -{ - /* - * Using __raw here because some code paths have - * preemption enabled. If preemption is enabled - * then interrupts should be enabled too, in which - * case we shouldn't have to worry about the watchdog - * going off. - */ - raw_cpu_write(watchdog_nmi_touch, true); -} -EXPORT_SYMBOL(arch_touch_nmi_watchdog); - #ifdef CONFIG_HARDLOCKUP_CHECK_TIMESTAMP static DEFINE_PER_CPU(ktime_t, last_timestamp); static DEFINE_PER_CPU(unsigned int, nmi_rearmed); @@ -115,11 +101,6 @@ static void watchdog_overflow_callback(struct perf_event *event, if (!watchdog_check_timestamp()) return; - if (__this_cpu_read(watchdog_nmi_touch) == true) { - __this_cpu_write(watchdog_nmi_touch, false); - return; - } - watchdog_hardlockup_check(smp_processor_id(), regs); }