diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-kernel-hardlockup_count | 7 | ||||
| -rw-r--r-- | Documentation/ABI/testing/sysfs-kernel-softlockup_count | 7 | ||||
| -rw-r--r-- | kernel/watchdog.c | 53 |
3 files changed, 67 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-kernel-hardlockup_count b/Documentation/ABI/testing/sysfs-kernel-hardlockup_count new file mode 100644 index 000000000000..dfdd4078b077 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-kernel-hardlockup_count @@ -0,0 +1,7 @@ +What: /sys/kernel/hardlockup_count +Date: May 2025 +KernelVersion: 6.16 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: + Shows how many times the system has detected a hard lockup since last boot. + Available only if CONFIG_HARDLOCKUP_DETECTOR is enabled. diff --git a/Documentation/ABI/testing/sysfs-kernel-softlockup_count b/Documentation/ABI/testing/sysfs-kernel-softlockup_count new file mode 100644 index 000000000000..337ff5531b5f --- /dev/null +++ b/Documentation/ABI/testing/sysfs-kernel-softlockup_count @@ -0,0 +1,7 @@ +What: /sys/kernel/softlockup_count +Date: May 2025 +KernelVersion: 6.16 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: + Shows how many times the system has detected a soft lockup since last boot. + Available only if CONFIG_SOFTLOCKUP_DETECTOR is enabled. diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 2d283e92be5a..80b56c002c7f 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -64,6 +64,29 @@ int __read_mostly sysctl_hardlockup_all_cpu_backtrace; */ unsigned int __read_mostly hardlockup_panic = IS_ENABLED(CONFIG_BOOTPARAM_HARDLOCKUP_PANIC); + +#ifdef CONFIG_SYSFS + +static unsigned int hardlockup_count; + +static ssize_t hardlockup_count_show(struct kobject *kobj, struct kobj_attribute *attr, + char *page) +{ + return sysfs_emit(page, "%u\n", hardlockup_count); +} + +static struct kobj_attribute hardlockup_count_attr = __ATTR_RO(hardlockup_count); + +static __init int kernel_hardlockup_sysfs_init(void) +{ + sysfs_add_file_to_group(kernel_kobj, &hardlockup_count_attr.attr, NULL); + return 0; +} + +late_initcall(kernel_hardlockup_sysfs_init); + +#endif // CONFIG_SYSFS + /* * We may not want to enable hard lockup detection by default in all cases, * for example when running the kernel as a guest on a hypervisor. In these @@ -170,6 +193,10 @@ void watchdog_hardlockup_check(unsigned int cpu, struct pt_regs *regs) unsigned int this_cpu = smp_processor_id(); unsigned long flags; +#ifdef CONFIG_SYSFS + ++hardlockup_count; +#endif + /* Only print hardlockups once. */ if (per_cpu(watchdog_hardlockup_warned, cpu)) return; @@ -312,6 +339,28 @@ unsigned int __read_mostly softlockup_panic = static bool softlockup_initialized __read_mostly; static u64 __read_mostly sample_period; +#ifdef CONFIG_SYSFS + +static unsigned int softlockup_count; + +static ssize_t softlockup_count_show(struct kobject *kobj, struct kobj_attribute *attr, + char *page) +{ + return sysfs_emit(page, "%u\n", softlockup_count); +} + +static struct kobj_attribute softlockup_count_attr = __ATTR_RO(softlockup_count); + +static __init int kernel_softlockup_sysfs_init(void) +{ + sysfs_add_file_to_group(kernel_kobj, &softlockup_count_attr.attr, NULL); + return 0; +} + +late_initcall(kernel_softlockup_sysfs_init); + +#endif // CONFIG_SYSFS + /* Timestamp taken after the last successful reschedule. */ static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts); /* Timestamp of the last softlockup report. */ @@ -743,6 +792,10 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) touch_ts = __this_cpu_read(watchdog_touch_ts); duration = is_softlockup(touch_ts, period_ts, now); if (unlikely(duration)) { +#ifdef CONFIG_SYSFS + ++softlockup_count; +#endif + /* * Prevent multiple soft-lockup reports if one cpu is already * engaged in dumping all cpu back traces. |