lockup_detector: Remove old softlockup code (2508ce18) · Commits · e / devices / android_kernel_teracube_emerald

kernel/softlockup.c

deleted100644 → 0

+0 −293

Original line number	Diff line number	Diff line
		/*
		* Detect Soft Lockups
		*
		* started by Ingo Molnar, Copyright (C) 2005, 2006 Red Hat, Inc.
		*
		* this code detects soft lockups: incidents in where on a CPU
		* the kernel does not reschedule for 10 seconds or more.
		*/
		#include <linux/mm.h>
		#include <linux/cpu.h>
		#include <linux/nmi.h>
		#include <linux/init.h>
		#include <linux/delay.h>
		#include <linux/freezer.h>
		#include <linux/kthread.h>
		#include <linux/lockdep.h>
		#include <linux/notifier.h>
		#include <linux/module.h>
		#include <linux/sysctl.h>

		#include <asm/irq_regs.h>

		static DEFINE_SPINLOCK(print_lock);

		static DEFINE_PER_CPU(unsigned long, softlockup_touch_ts); /* touch timestamp */
		static DEFINE_PER_CPU(unsigned long, softlockup_print_ts); /* print timestamp */
		static DEFINE_PER_CPU(struct task_struct *, softlockup_watchdog);
		static DEFINE_PER_CPU(bool, softlock_touch_sync);

		static int __read_mostly did_panic;
		int __read_mostly softlockup_thresh = 60;

		/*
		* Should we panic (and reboot, if panic_timeout= is set) when a
		* soft-lockup occurs:
		*/
		unsigned int __read_mostly softlockup_panic =
		CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC_VALUE;

		static int __init softlockup_panic_setup(char *str)
		{
		softlockup_panic = simple_strtoul(str, NULL, 0);

		return 1;
		}
		__setup("softlockup_panic=", softlockup_panic_setup);

		static int
		softlock_panic(struct notifier_block this, unsigned long event, void ptr)
		{
		did_panic = 1;

		return NOTIFY_DONE;
		}

		static struct notifier_block panic_block = {
		.notifier_call = softlock_panic,
		};

		/*
		* Returns seconds, approximately. We don't need nanosecond
		* resolution, and we don't need to waste time with a big divide when
		* 2^30ns == 1.074s.
		*/
		static unsigned long get_timestamp(int this_cpu)
		{
		return cpu_clock(this_cpu) >> 30LL; /* 2^30 ~= 10^9 */
		}

		static void __touch_softlockup_watchdog(void)
		{
		int this_cpu = raw_smp_processor_id();

		__raw_get_cpu_var(softlockup_touch_ts) = get_timestamp(this_cpu);
		}

		void touch_softlockup_watchdog(void)
		{
		__raw_get_cpu_var(softlockup_touch_ts) = 0;
		}
		EXPORT_SYMBOL(touch_softlockup_watchdog);

		void touch_softlockup_watchdog_sync(void)
		{
		__raw_get_cpu_var(softlock_touch_sync) = true;
		__raw_get_cpu_var(softlockup_touch_ts) = 0;
		}

		void touch_all_softlockup_watchdogs(void)
		{
		int cpu;

		/* Cause each CPU to re-update its timestamp rather than complain */
		for_each_online_cpu(cpu)
		per_cpu(softlockup_touch_ts, cpu) = 0;
		}
		EXPORT_SYMBOL(touch_all_softlockup_watchdogs);

		int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
		void __user *buffer,
		size_t lenp, loff_t ppos)
		{
		touch_all_softlockup_watchdogs();
		return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
		}

		/*
		* This callback runs from the timer interrupt, and checks
		* whether the watchdog thread has hung or not:
		*/
		void softlockup_tick(void)
		{
		int this_cpu = smp_processor_id();
		unsigned long touch_ts = per_cpu(softlockup_touch_ts, this_cpu);
		unsigned long print_ts;
		struct pt_regs *regs = get_irq_regs();
		unsigned long now;

		/* Is detection switched off? */
		if (!per_cpu(softlockup_watchdog, this_cpu) \|\| softlockup_thresh <= 0) {
		/* Be sure we don't false trigger if switched back on */
		if (touch_ts)
		per_cpu(softlockup_touch_ts, this_cpu) = 0;
		return;
		}

		if (touch_ts == 0) {
		if (unlikely(per_cpu(softlock_touch_sync, this_cpu))) {
		/*
		* If the time stamp was touched atomically
		* make sure the scheduler tick is up to date.
		*/
		per_cpu(softlock_touch_sync, this_cpu) = false;
		sched_clock_tick();
		}
		__touch_softlockup_watchdog();
		return;
		}

		print_ts = per_cpu(softlockup_print_ts, this_cpu);

		/* report at most once a second */
		if (print_ts == touch_ts \|\| did_panic)
		return;

		/* do not print during early bootup: */
		if (unlikely(system_state != SYSTEM_RUNNING)) {
		__touch_softlockup_watchdog();
		return;
		}

		now = get_timestamp(this_cpu);

		/*
		* Wake up the high-prio watchdog task twice per
		* threshold timespan.
		*/
		if (time_after(now - softlockup_thresh/2, touch_ts))
		wake_up_process(per_cpu(softlockup_watchdog, this_cpu));

		/* Warn about unreasonable delays: */
		if (time_before_eq(now - softlockup_thresh, touch_ts))
		return;

		per_cpu(softlockup_print_ts, this_cpu) = touch_ts;

		spin_lock(&print_lock);
		printk(KERN_ERR "BUG: soft lockup - CPU#%d stuck for %lus! [%s:%d]\n",
		this_cpu, now - touch_ts,
		current->comm, task_pid_nr(current));
		print_modules();
		print_irqtrace_events(current);
		if (regs)
		show_regs(regs);
		else
		dump_stack();
		spin_unlock(&print_lock);

		if (softlockup_panic)
		panic("softlockup: hung tasks");
		}

		/*
		* The watchdog thread - runs every second and touches the timestamp.
		*/
		static int watchdog(void *__bind_cpu)
		{
		struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };

		sched_setscheduler(current, SCHED_FIFO, &param);

		/* initialize timestamp */
		__touch_softlockup_watchdog();

		set_current_state(TASK_INTERRUPTIBLE);
		/*
		* Run briefly once per second to reset the softlockup timestamp.
		* If this gets delayed for more than 60 seconds then the
		* debug-printout triggers in softlockup_tick().
		*/
		while (!kthread_should_stop()) {
		__touch_softlockup_watchdog();
		schedule();

		if (kthread_should_stop())
		break;

		set_current_state(TASK_INTERRUPTIBLE);
		}
		__set_current_state(TASK_RUNNING);

		return 0;
		}

		/*
		* Create/destroy watchdog threads as CPUs come and go:
		*/
		static int __cpuinit
		cpu_callback(struct notifier_block nfb, unsigned long action, void hcpu)
		{
		int hotcpu = (unsigned long)hcpu;
		struct task_struct *p;

		switch (action) {
		case CPU_UP_PREPARE:
		case CPU_UP_PREPARE_FROZEN:
		BUG_ON(per_cpu(softlockup_watchdog, hotcpu));
		p = kthread_create(watchdog, hcpu, "watchdog/%d", hotcpu);
		if (IS_ERR(p)) {
		printk(KERN_ERR "watchdog for %i failed\n", hotcpu);
		return NOTIFY_BAD;
		}
		per_cpu(softlockup_touch_ts, hotcpu) = 0;
		per_cpu(softlockup_watchdog, hotcpu) = p;
		kthread_bind(p, hotcpu);
		break;
		case CPU_ONLINE:
		case CPU_ONLINE_FROZEN:
		wake_up_process(per_cpu(softlockup_watchdog, hotcpu));
		break;
		#ifdef CONFIG_HOTPLUG_CPU
		case CPU_UP_CANCELED:
		case CPU_UP_CANCELED_FROZEN:
		if (!per_cpu(softlockup_watchdog, hotcpu))
		break;
		/* Unbind so it can run. Fall thru. */
		kthread_bind(per_cpu(softlockup_watchdog, hotcpu),
		cpumask_any(cpu_online_mask));
		case CPU_DEAD:
		case CPU_DEAD_FROZEN:
		p = per_cpu(softlockup_watchdog, hotcpu);
		per_cpu(softlockup_watchdog, hotcpu) = NULL;
		kthread_stop(p);
		break;
		#endif /* CONFIG_HOTPLUG_CPU */
		}
		return NOTIFY_OK;
		}

		static struct notifier_block __cpuinitdata cpu_nfb = {
		.notifier_call = cpu_callback
		};

		static int __initdata nosoftlockup;

		static int __init nosoftlockup_setup(char *str)
		{
		nosoftlockup = 1;
		return 1;
		}
		__setup("nosoftlockup", nosoftlockup_setup);

		static int __init spawn_softlockup_task(void)
		{
		void cpu = (void )(long)smp_processor_id();
		int err;

		if (nosoftlockup)
		return 0;

		err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
		if (err == NOTIFY_BAD) {
		BUG();
		return 1;
		}
		cpu_callback(&cpu_nfb, CPU_ONLINE, cpu);
		register_cpu_notifier(&cpu_nfb);

		atomic_notifier_chain_register(&panic_notifier_list, &panic_block);

		return 0;
		}
		early_initcall(spawn_softlockup_task);

kernel/sysctl.c

+10 −12

Original line number	Diff line number	Diff line
		@@ -108,7 +108,7 @@ extern int blk_iopoll_enabled;
		#endif

		/* Constants used for minimum and maximum */
		#ifdef CONFIG_DETECT_SOFTLOCKUP
		#ifdef CONFIG_LOCKUP_DETECTOR
		static int sixty = 60;
		static int neg_one = -1;
		#endif
		@@ -703,6 +703,15 @@ static struct ctl_table kern_table[] = {
		.extra1 = &neg_one,
		.extra2 = &sixty,
		},
		{
		.procname = "softlockup_panic",
		.data = &softlockup_panic,
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = proc_dointvec_minmax,
		.extra1 = &zero,
		.extra2 = &one,
		},
		#endif
		#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) && !defined(CONFIG_LOCKUP_DETECTOR)
		{
		@@ -807,17 +816,6 @@ static struct ctl_table kern_table[] = {
		.proc_handler = proc_dointvec,
		},
		#endif
		#ifdef CONFIG_DETECT_SOFTLOCKUP
		{
		.procname = "softlockup_panic",
		.data = &softlockup_panic,
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = proc_dointvec_minmax,
		.extra1 = &zero,
		.extra2 = &one,
		},
		#endif
		#ifdef CONFIG_DETECT_HUNG_TASK
		{
		.procname = "hung_task_panic",