X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=kernel%2Fwatchdog.c;fp=kernel%2Fwatchdog.c;h=18bb15776c57162b60675adf69e7afd765b34fb0;hb=f2ec334db8d14ae3ec2e4bf8d974f75b8f772e26;hp=7f9c3c52ecc12ef5d0de1728839218ff87c2dc7b;hpb=81e20d4d8d0317ecf1c7d193a52ab26cf74e1737;p=mv-sheeva.git diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 7f9c3c52ecc..18bb15776c5 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -27,7 +27,7 @@ #include #include -int watchdog_enabled; +int watchdog_enabled = 1; int __read_mostly softlockup_thresh = 60; static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts); @@ -43,10 +43,6 @@ static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts_saved); static DEFINE_PER_CPU(struct perf_event *, watchdog_ev); #endif -static int __read_mostly did_panic; -static int __initdata no_watchdog; - - /* boot commands */ /* * Should we panic when a soft-lockup or hard-lockup occurs: @@ -58,6 +54,8 @@ static int __init hardlockup_panic_setup(char *str) { if (!strncmp(str, "panic", 5)) hardlockup_panic = 1; + else if (!strncmp(str, "0", 1)) + watchdog_enabled = 0; return 1; } __setup("nmi_watchdog=", hardlockup_panic_setup); @@ -76,7 +74,7 @@ __setup("softlockup_panic=", softlockup_panic_setup); static int __init nowatchdog_setup(char *str) { - no_watchdog = 1; + watchdog_enabled = 0; return 1; } __setup("nowatchdog", nowatchdog_setup); @@ -84,7 +82,7 @@ __setup("nowatchdog", nowatchdog_setup); /* deprecated */ static int __init nosoftlockup_setup(char *str) { - no_watchdog = 1; + watchdog_enabled = 0; return 1; } __setup("nosoftlockup", nosoftlockup_setup); @@ -117,12 +115,12 @@ static void __touch_watchdog(void) { int this_cpu = smp_processor_id(); - __get_cpu_var(watchdog_touch_ts) = get_timestamp(this_cpu); + __this_cpu_write(watchdog_touch_ts, get_timestamp(this_cpu)); } void touch_softlockup_watchdog(void) { - __raw_get_cpu_var(watchdog_touch_ts) = 0; + __this_cpu_write(watchdog_touch_ts, 0); } EXPORT_SYMBOL(touch_softlockup_watchdog); @@ -166,12 +164,12 @@ void touch_softlockup_watchdog_sync(void) /* watchdog detector functions */ static int is_hardlockup(void) { - unsigned long hrint = __get_cpu_var(hrtimer_interrupts); + unsigned long hrint = __this_cpu_read(hrtimer_interrupts); - if (__get_cpu_var(hrtimer_interrupts_saved) == hrint) + if (__this_cpu_read(hrtimer_interrupts_saved) == hrint) return 1; - __get_cpu_var(hrtimer_interrupts_saved) = hrint; + __this_cpu_write(hrtimer_interrupts_saved, hrint); return 0; } #endif @@ -187,18 +185,6 @@ static int is_softlockup(unsigned long touch_ts) return 0; } -static int -watchdog_panic(struct notifier_block *this, unsigned long event, void *ptr) -{ - did_panic = 1; - - return NOTIFY_DONE; -} - -static struct notifier_block panic_block = { - .notifier_call = watchdog_panic, -}; - #ifdef CONFIG_HARDLOCKUP_DETECTOR static struct perf_event_attr wd_hw_attr = { .type = PERF_TYPE_HARDWARE, @@ -209,15 +195,15 @@ static struct perf_event_attr wd_hw_attr = { }; /* Callback function for perf event subsystem */ -void watchdog_overflow_callback(struct perf_event *event, int nmi, +static void watchdog_overflow_callback(struct perf_event *event, int nmi, struct perf_sample_data *data, struct pt_regs *regs) { /* Ensure the watchdog never gets throttled */ event->hw.interrupts = 0; - if (__get_cpu_var(watchdog_nmi_touch) == true) { - __get_cpu_var(watchdog_nmi_touch) = false; + if (__this_cpu_read(watchdog_nmi_touch) == true) { + __this_cpu_write(watchdog_nmi_touch, false); return; } @@ -231,7 +217,7 @@ void watchdog_overflow_callback(struct perf_event *event, int nmi, int this_cpu = smp_processor_id(); /* only print hardlockups once */ - if (__get_cpu_var(hard_watchdog_warn) == true) + if (__this_cpu_read(hard_watchdog_warn) == true) return; if (hardlockup_panic) @@ -239,16 +225,16 @@ void watchdog_overflow_callback(struct perf_event *event, int nmi, else WARN(1, "Watchdog detected hard LOCKUP on cpu %d", this_cpu); - __get_cpu_var(hard_watchdog_warn) = true; + __this_cpu_write(hard_watchdog_warn, true); return; } - __get_cpu_var(hard_watchdog_warn) = false; + __this_cpu_write(hard_watchdog_warn, false); return; } static void watchdog_interrupt_count(void) { - __get_cpu_var(hrtimer_interrupts)++; + __this_cpu_inc(hrtimer_interrupts); } #else static inline void watchdog_interrupt_count(void) { return; } @@ -257,7 +243,7 @@ static inline void watchdog_interrupt_count(void) { return; } /* watchdog kicker functions */ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) { - unsigned long touch_ts = __get_cpu_var(watchdog_touch_ts); + unsigned long touch_ts = __this_cpu_read(watchdog_touch_ts); struct pt_regs *regs = get_irq_regs(); int duration; @@ -265,18 +251,18 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) watchdog_interrupt_count(); /* kick the softlockup detector */ - wake_up_process(__get_cpu_var(softlockup_watchdog)); + wake_up_process(__this_cpu_read(softlockup_watchdog)); /* .. and repeat */ hrtimer_forward_now(hrtimer, ns_to_ktime(get_sample_period())); if (touch_ts == 0) { - if (unlikely(__get_cpu_var(softlockup_touch_sync))) { + if (unlikely(__this_cpu_read(softlockup_touch_sync))) { /* * If the time stamp was touched atomically * make sure the scheduler tick is up to date. */ - __get_cpu_var(softlockup_touch_sync) = false; + __this_cpu_write(softlockup_touch_sync, false); sched_clock_tick(); } __touch_watchdog(); @@ -292,7 +278,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) duration = is_softlockup(touch_ts); if (unlikely(duration)) { /* only warn once */ - if (__get_cpu_var(soft_watchdog_warn) == true) + if (__this_cpu_read(soft_watchdog_warn) == true) return HRTIMER_RESTART; printk(KERN_ERR "BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n", @@ -307,9 +293,9 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) if (softlockup_panic) panic("softlockup: hung tasks"); - __get_cpu_var(soft_watchdog_warn) = true; + __this_cpu_write(soft_watchdog_warn, true); } else - __get_cpu_var(soft_watchdog_warn) = false; + __this_cpu_write(soft_watchdog_warn, false); return HRTIMER_RESTART; } @@ -320,7 +306,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) */ static int watchdog(void *unused) { - struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; + static struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; struct hrtimer *hrtimer = &__raw_get_cpu_var(watchdog_hrtimer); sched_setscheduler(current, SCHED_FIFO, ¶m); @@ -371,14 +357,21 @@ static int watchdog_nmi_enable(int cpu) /* Try to register using hardware perf events */ wd_attr = &wd_hw_attr; wd_attr->sample_period = hw_nmi_get_sample_period(); - event = perf_event_create_kernel_counter(wd_attr, cpu, -1, watchdog_overflow_callback); + event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback); if (!IS_ERR(event)) { printk(KERN_INFO "NMI watchdog enabled, takes one hw-pmu counter.\n"); goto out_save; } - printk(KERN_ERR "NMI watchdog failed to create perf event on cpu%i: %p\n", cpu, event); - return -1; + + /* vary the KERN level based on the returned errno */ + if (PTR_ERR(event) == -EOPNOTSUPP) + printk(KERN_INFO "NMI watchdog disabled (cpu%i): not supported (no LAPIC?)\n", cpu); + else if (PTR_ERR(event) == -ENOENT) + printk(KERN_WARNING "NMI watchdog disabled (cpu%i): hardware events not enabled\n", cpu); + else + printk(KERN_ERR "NMI watchdog disabled (cpu%i): unable to create perf event: %ld\n", cpu, PTR_ERR(event)); + return PTR_ERR(event); /* success path */ out_save: @@ -422,17 +415,19 @@ static int watchdog_prepare_cpu(int cpu) static int watchdog_enable(int cpu) { struct task_struct *p = per_cpu(softlockup_watchdog, cpu); + int err; /* enable the perf event */ - if (watchdog_nmi_enable(cpu) != 0) - return -1; + err = watchdog_nmi_enable(cpu); + if (err) + return err; /* create the watchdog thread */ if (!p) { p = kthread_create(watchdog, (void *)(unsigned long)cpu, "watchdog/%d", cpu); if (IS_ERR(p)) { printk(KERN_ERR "softlockup watchdog for %i failed\n", cpu); - return -1; + return PTR_ERR(p); } kthread_bind(p, cpu); per_cpu(watchdog_touch_ts, cpu) = 0; @@ -440,9 +435,6 @@ static int watchdog_enable(int cpu) wake_up_process(p); } - /* if any cpu succeeds, watchdog is considered enabled for the system */ - watchdog_enabled = 1; - return 0; } @@ -470,12 +462,16 @@ static void watchdog_disable(int cpu) static void watchdog_enable_all_cpus(void) { int cpu; - int result = 0; + + watchdog_enabled = 0; for_each_online_cpu(cpu) - result += watchdog_enable(cpu); + if (!watchdog_enable(cpu)) + /* if any cpu succeeds, watchdog is considered + enabled for the system */ + watchdog_enabled = 1; - if (result) + if (!watchdog_enabled) printk(KERN_ERR "watchdog: failed to be enabled on some cpus\n"); } @@ -503,10 +499,12 @@ int proc_dowatchdog_enabled(struct ctl_table *table, int write, { proc_dointvec(table, write, buffer, length, ppos); - if (watchdog_enabled) - watchdog_enable_all_cpus(); - else - watchdog_disable_all_cpus(); + if (write) { + if (watchdog_enabled) + watchdog_enable_all_cpus(); + else + watchdog_disable_all_cpus(); + } return 0; } @@ -526,17 +524,17 @@ static int __cpuinit cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) { int hotcpu = (unsigned long)hcpu; + int err = 0; switch (action) { case CPU_UP_PREPARE: case CPU_UP_PREPARE_FROZEN: - if (watchdog_prepare_cpu(hotcpu)) - return NOTIFY_BAD; + err = watchdog_prepare_cpu(hotcpu); break; case CPU_ONLINE: case CPU_ONLINE_FROZEN: - if (watchdog_enable(hotcpu)) - return NOTIFY_BAD; + if (watchdog_enabled) + err = watchdog_enable(hotcpu); break; #ifdef CONFIG_HOTPLUG_CPU case CPU_UP_CANCELED: @@ -549,29 +547,23 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) break; #endif /* CONFIG_HOTPLUG_CPU */ } - return NOTIFY_OK; + return notifier_from_errno(err); } static struct notifier_block __cpuinitdata cpu_nfb = { .notifier_call = cpu_callback }; -static int __init spawn_watchdog_task(void) +void __init lockup_detector_init(void) { void *cpu = (void *)(long)smp_processor_id(); int err; - if (no_watchdog) - return 0; - err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu); - WARN_ON(err == NOTIFY_BAD); + WARN_ON(notifier_to_errno(err)); cpu_callback(&cpu_nfb, CPU_ONLINE, cpu); register_cpu_notifier(&cpu_nfb); - atomic_notifier_chain_register(&panic_notifier_list, &panic_block); - - return 0; + return; } -early_initcall(spawn_watchdog_task);