Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Detect Soft Lockups |
| 3 | * |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 4 | * started by Ingo Molnar, Copyright (C) 2005, 2006 Red Hat, Inc. |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 5 | * |
| 6 | * this code detects soft lockups: incidents in where on a CPU |
| 7 | * the kernel does not reschedule for 10 seconds or more. |
| 8 | */ |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 9 | #include <linux/mm.h> |
| 10 | #include <linux/cpu.h> |
Ingo Molnar | 82a1fcb | 2008-01-25 21:08:02 +0100 | [diff] [blame] | 11 | #include <linux/nmi.h> |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 12 | #include <linux/init.h> |
| 13 | #include <linux/delay.h> |
Rafael J. Wysocki | 8314418 | 2007-07-17 04:03:35 -0700 | [diff] [blame] | 14 | #include <linux/freezer.h> |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 15 | #include <linux/kthread.h> |
Vegard Nossum | 8d5be7f | 2008-06-25 08:50:10 +0200 | [diff] [blame] | 16 | #include <linux/lockdep.h> |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 17 | #include <linux/notifier.h> |
| 18 | #include <linux/module.h> |
Mandeep Singh Baines | baf48f6 | 2009-01-12 21:15:17 -0800 | [diff] [blame] | 19 | #include <linux/sysctl.h> |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 20 | |
Ingo Molnar | 43581a1 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 21 | #include <asm/irq_regs.h> |
| 22 | |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 23 | static DEFINE_SPINLOCK(print_lock); |
| 24 | |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 25 | static DEFINE_PER_CPU(unsigned long, touch_timestamp); |
| 26 | static DEFINE_PER_CPU(unsigned long, print_timestamp); |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 27 | static DEFINE_PER_CPU(struct task_struct *, watchdog_task); |
| 28 | |
Ingo Molnar | 9073908 | 2008-01-25 21:08:34 +0100 | [diff] [blame] | 29 | static int __read_mostly did_panic; |
Dimitri Sivanich | 9383d96 | 2008-05-12 21:21:14 +0200 | [diff] [blame] | 30 | int __read_mostly softlockup_thresh = 60; |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 31 | |
Ingo Molnar | 9c44bc0 | 2008-05-12 21:21:04 +0200 | [diff] [blame] | 32 | /* |
| 33 | * Should we panic (and reboot, if panic_timeout= is set) when a |
| 34 | * soft-lockup occurs: |
| 35 | */ |
| 36 | unsigned int __read_mostly softlockup_panic = |
| 37 | CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC_VALUE; |
| 38 | |
| 39 | static int __init softlockup_panic_setup(char *str) |
| 40 | { |
| 41 | softlockup_panic = simple_strtoul(str, NULL, 0); |
| 42 | |
| 43 | return 1; |
| 44 | } |
| 45 | __setup("softlockup_panic=", softlockup_panic_setup); |
| 46 | |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 47 | static int |
| 48 | softlock_panic(struct notifier_block *this, unsigned long event, void *ptr) |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 49 | { |
| 50 | did_panic = 1; |
| 51 | |
| 52 | return NOTIFY_DONE; |
| 53 | } |
| 54 | |
| 55 | static struct notifier_block panic_block = { |
| 56 | .notifier_call = softlock_panic, |
| 57 | }; |
| 58 | |
Jeremy Fitzhardinge | 966812d | 2007-05-08 00:28:02 -0700 | [diff] [blame] | 59 | /* |
| 60 | * Returns seconds, approximately. We don't need nanosecond |
| 61 | * resolution, and we don't need to waste time with a big divide when |
| 62 | * 2^30ns == 1.074s. |
| 63 | */ |
Ingo Molnar | a3b13c2 | 2007-10-16 23:26:06 -0700 | [diff] [blame] | 64 | static unsigned long get_timestamp(int this_cpu) |
Jeremy Fitzhardinge | 966812d | 2007-05-08 00:28:02 -0700 | [diff] [blame] | 65 | { |
Ingo Molnar | 82a1fcb | 2008-01-25 21:08:02 +0100 | [diff] [blame] | 66 | return cpu_clock(this_cpu) >> 30LL; /* 2^30 ~= 10^9 */ |
Jeremy Fitzhardinge | 966812d | 2007-05-08 00:28:02 -0700 | [diff] [blame] | 67 | } |
| 68 | |
Jason Wessel | 8c2238e | 2008-05-27 12:23:29 -0500 | [diff] [blame] | 69 | static void __touch_softlockup_watchdog(void) |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 70 | { |
Ingo Molnar | a3b13c2 | 2007-10-16 23:26:06 -0700 | [diff] [blame] | 71 | int this_cpu = raw_smp_processor_id(); |
| 72 | |
| 73 | __raw_get_cpu_var(touch_timestamp) = get_timestamp(this_cpu); |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 74 | } |
Jason Wessel | 8c2238e | 2008-05-27 12:23:29 -0500 | [diff] [blame] | 75 | |
| 76 | void touch_softlockup_watchdog(void) |
| 77 | { |
| 78 | __raw_get_cpu_var(touch_timestamp) = 0; |
| 79 | } |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 80 | EXPORT_SYMBOL(touch_softlockup_watchdog); |
| 81 | |
Jeremy Fitzhardinge | 04c9167 | 2007-05-08 00:28:05 -0700 | [diff] [blame] | 82 | void touch_all_softlockup_watchdogs(void) |
| 83 | { |
| 84 | int cpu; |
| 85 | |
| 86 | /* Cause each CPU to re-update its timestamp rather than complain */ |
| 87 | for_each_online_cpu(cpu) |
| 88 | per_cpu(touch_timestamp, cpu) = 0; |
| 89 | } |
| 90 | EXPORT_SYMBOL(touch_all_softlockup_watchdogs); |
| 91 | |
Mandeep Singh Baines | baf48f6 | 2009-01-12 21:15:17 -0800 | [diff] [blame] | 92 | int proc_dosoftlockup_thresh(struct ctl_table *table, int write, |
| 93 | struct file *filp, void __user *buffer, |
| 94 | size_t *lenp, loff_t *ppos) |
| 95 | { |
| 96 | touch_all_softlockup_watchdogs(); |
| 97 | return proc_dointvec_minmax(table, write, filp, buffer, lenp, ppos); |
| 98 | } |
| 99 | |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 100 | /* |
| 101 | * This callback runs from the timer interrupt, and checks |
| 102 | * whether the watchdog thread has hung or not: |
| 103 | */ |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 104 | void softlockup_tick(void) |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 105 | { |
| 106 | int this_cpu = smp_processor_id(); |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 107 | unsigned long touch_timestamp = per_cpu(touch_timestamp, this_cpu); |
Jeremy Fitzhardinge | 966812d | 2007-05-08 00:28:02 -0700 | [diff] [blame] | 108 | unsigned long print_timestamp; |
Ingo Molnar | 43581a1 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 109 | struct pt_regs *regs = get_irq_regs(); |
Jeremy Fitzhardinge | 966812d | 2007-05-08 00:28:02 -0700 | [diff] [blame] | 110 | unsigned long now; |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 111 | |
Dimitri Sivanich | 9383d96 | 2008-05-12 21:21:14 +0200 | [diff] [blame] | 112 | /* Is detection switched off? */ |
| 113 | if (!per_cpu(watchdog_task, this_cpu) || softlockup_thresh <= 0) { |
| 114 | /* Be sure we don't false trigger if switched back on */ |
| 115 | if (touch_timestamp) |
| 116 | per_cpu(touch_timestamp, this_cpu) = 0; |
| 117 | return; |
| 118 | } |
| 119 | |
Jeremy Fitzhardinge | 04c9167 | 2007-05-08 00:28:05 -0700 | [diff] [blame] | 120 | if (touch_timestamp == 0) { |
Jason Wessel | 8c2238e | 2008-05-27 12:23:29 -0500 | [diff] [blame] | 121 | __touch_softlockup_watchdog(); |
Jeremy Fitzhardinge | 966812d | 2007-05-08 00:28:02 -0700 | [diff] [blame] | 122 | return; |
Jeremy Fitzhardinge | 04c9167 | 2007-05-08 00:28:05 -0700 | [diff] [blame] | 123 | } |
Jeremy Fitzhardinge | 966812d | 2007-05-08 00:28:02 -0700 | [diff] [blame] | 124 | |
| 125 | print_timestamp = per_cpu(print_timestamp, this_cpu); |
| 126 | |
| 127 | /* report at most once a second */ |
Johannes Weiner | 3e2f69f | 2008-07-01 09:12:04 +0200 | [diff] [blame] | 128 | if (print_timestamp == touch_timestamp || did_panic) |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 129 | return; |
| 130 | |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 131 | /* do not print during early bootup: */ |
| 132 | if (unlikely(system_state != SYSTEM_RUNNING)) { |
Jason Wessel | 8c2238e | 2008-05-27 12:23:29 -0500 | [diff] [blame] | 133 | __touch_softlockup_watchdog(); |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 134 | return; |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 135 | } |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 136 | |
Ingo Molnar | a3b13c2 | 2007-10-16 23:26:06 -0700 | [diff] [blame] | 137 | now = get_timestamp(this_cpu); |
Jeremy Fitzhardinge | 966812d | 2007-05-08 00:28:02 -0700 | [diff] [blame] | 138 | |
Johannes Weiner | dd7a1e5 | 2008-06-27 15:07:21 +0200 | [diff] [blame] | 139 | /* |
| 140 | * Wake up the high-prio watchdog task twice per |
| 141 | * threshold timespan. |
| 142 | */ |
| 143 | if (now > touch_timestamp + softlockup_thresh/2) |
Peter Zijlstra | ed50d6c | 2008-02-02 00:23:08 +0100 | [diff] [blame] | 144 | wake_up_process(per_cpu(watchdog_task, this_cpu)); |
| 145 | |
Ingo Molnar | 82a1fcb | 2008-01-25 21:08:02 +0100 | [diff] [blame] | 146 | /* Warn about unreasonable delays: */ |
Ravikiran G Thirumalai | c4f3b63 | 2007-10-16 23:26:09 -0700 | [diff] [blame] | 147 | if (now <= (touch_timestamp + softlockup_thresh)) |
Ingo Molnar | 43581a1 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 148 | return; |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 149 | |
Ingo Molnar | 43581a1 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 150 | per_cpu(print_timestamp, this_cpu) = touch_timestamp; |
| 151 | |
| 152 | spin_lock(&print_lock); |
Ravikiran G Thirumalai | c4f3b63 | 2007-10-16 23:26:09 -0700 | [diff] [blame] | 153 | printk(KERN_ERR "BUG: soft lockup - CPU#%d stuck for %lus! [%s:%d]\n", |
| 154 | this_cpu, now - touch_timestamp, |
Pavel Emelyanov | ba25f9d | 2007-10-18 23:40:40 -0700 | [diff] [blame] | 155 | current->comm, task_pid_nr(current)); |
Arjan van de Ven | 688c917 | 2008-06-16 15:51:08 -0700 | [diff] [blame] | 156 | print_modules(); |
Vegard Nossum | 8d5be7f | 2008-06-25 08:50:10 +0200 | [diff] [blame] | 157 | print_irqtrace_events(current); |
Ingo Molnar | 43581a1 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 158 | if (regs) |
| 159 | show_regs(regs); |
| 160 | else |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 161 | dump_stack(); |
Ingo Molnar | 43581a1 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 162 | spin_unlock(&print_lock); |
Ingo Molnar | 9c44bc0 | 2008-05-12 21:21:04 +0200 | [diff] [blame] | 163 | |
| 164 | if (softlockup_panic) |
| 165 | panic("softlockup: hung tasks"); |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 166 | } |
| 167 | |
| 168 | /* |
| 169 | * The watchdog thread - runs every second and touches the timestamp. |
| 170 | */ |
Ingo Molnar | a5f2ce3 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 171 | static int watchdog(void *__bind_cpu) |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 172 | { |
Oleg Nesterov | 02fb614 | 2007-05-08 00:24:03 -0700 | [diff] [blame] | 173 | struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 174 | |
| 175 | sched_setscheduler(current, SCHED_FIFO, ¶m); |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 176 | |
Jeremy Fitzhardinge | 966812d | 2007-05-08 00:28:02 -0700 | [diff] [blame] | 177 | /* initialize timestamp */ |
Jason Wessel | 8c2238e | 2008-05-27 12:23:29 -0500 | [diff] [blame] | 178 | __touch_softlockup_watchdog(); |
Jeremy Fitzhardinge | 966812d | 2007-05-08 00:28:02 -0700 | [diff] [blame] | 179 | |
Dmitry Adamushko | 7be2a03 | 2008-02-08 15:41:13 +0100 | [diff] [blame] | 180 | set_current_state(TASK_INTERRUPTIBLE); |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 181 | /* |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 182 | * Run briefly once per second to reset the softlockup timestamp. |
Ingo Molnar | 82a1fcb | 2008-01-25 21:08:02 +0100 | [diff] [blame] | 183 | * If this gets delayed for more than 60 seconds then the |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 184 | * debug-printout triggers in softlockup_tick(). |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 185 | */ |
| 186 | while (!kthread_should_stop()) { |
Jason Wessel | 8c2238e | 2008-05-27 12:23:29 -0500 | [diff] [blame] | 187 | __touch_softlockup_watchdog(); |
Peter Zijlstra | ed50d6c | 2008-02-02 00:23:08 +0100 | [diff] [blame] | 188 | schedule(); |
| 189 | |
| 190 | if (kthread_should_stop()) |
| 191 | break; |
Ingo Molnar | 82a1fcb | 2008-01-25 21:08:02 +0100 | [diff] [blame] | 192 | |
Dmitry Adamushko | 7be2a03 | 2008-02-08 15:41:13 +0100 | [diff] [blame] | 193 | set_current_state(TASK_INTERRUPTIBLE); |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 194 | } |
Dmitry Adamushko | 7be2a03 | 2008-02-08 15:41:13 +0100 | [diff] [blame] | 195 | __set_current_state(TASK_RUNNING); |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 196 | |
| 197 | return 0; |
| 198 | } |
| 199 | |
| 200 | /* |
| 201 | * Create/destroy watchdog threads as CPUs come and go: |
| 202 | */ |
Chandra Seetharaman | 8c78f30 | 2006-07-30 03:03:35 -0700 | [diff] [blame] | 203 | static int __cpuinit |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 204 | cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) |
| 205 | { |
| 206 | int hotcpu = (unsigned long)hcpu; |
| 207 | struct task_struct *p; |
| 208 | |
| 209 | switch (action) { |
| 210 | case CPU_UP_PREPARE: |
Rafael J. Wysocki | 8bb7844 | 2007-05-09 02:35:10 -0700 | [diff] [blame] | 211 | case CPU_UP_PREPARE_FROZEN: |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 212 | BUG_ON(per_cpu(watchdog_task, hotcpu)); |
| 213 | p = kthread_create(watchdog, hcpu, "watchdog/%d", hotcpu); |
| 214 | if (IS_ERR(p)) { |
Ingo Molnar | a5f2ce3 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 215 | printk(KERN_ERR "watchdog for %i failed\n", hotcpu); |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 216 | return NOTIFY_BAD; |
| 217 | } |
Ingo Molnar | a5f2ce3 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 218 | per_cpu(touch_timestamp, hotcpu) = 0; |
| 219 | per_cpu(watchdog_task, hotcpu) = p; |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 220 | kthread_bind(p, hotcpu); |
Ingo Molnar | a5f2ce3 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 221 | break; |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 222 | case CPU_ONLINE: |
Rafael J. Wysocki | 8bb7844 | 2007-05-09 02:35:10 -0700 | [diff] [blame] | 223 | case CPU_ONLINE_FROZEN: |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 224 | wake_up_process(per_cpu(watchdog_task, hotcpu)); |
| 225 | break; |
| 226 | #ifdef CONFIG_HOTPLUG_CPU |
Peter Zijlstra | ed50d6c | 2008-02-02 00:23:08 +0100 | [diff] [blame] | 227 | case CPU_UP_CANCELED: |
| 228 | case CPU_UP_CANCELED_FROZEN: |
| 229 | if (!per_cpu(watchdog_task, hotcpu)) |
| 230 | break; |
| 231 | /* Unbind so it can run. Fall thru. */ |
| 232 | kthread_bind(per_cpu(watchdog_task, hotcpu), |
Rusty Russell | f1fc057 | 2009-01-01 10:12:23 +1030 | [diff] [blame] | 233 | cpumask_any(cpu_online_mask)); |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 234 | case CPU_DEAD: |
Rafael J. Wysocki | 8bb7844 | 2007-05-09 02:35:10 -0700 | [diff] [blame] | 235 | case CPU_DEAD_FROZEN: |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 236 | p = per_cpu(watchdog_task, hotcpu); |
| 237 | per_cpu(watchdog_task, hotcpu) = NULL; |
| 238 | kthread_stop(p); |
| 239 | break; |
| 240 | #endif /* CONFIG_HOTPLUG_CPU */ |
Ingo Molnar | a5f2ce3 | 2007-10-16 23:26:08 -0700 | [diff] [blame] | 241 | } |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 242 | return NOTIFY_OK; |
| 243 | } |
| 244 | |
Chandra Seetharaman | 8c78f30 | 2006-07-30 03:03:35 -0700 | [diff] [blame] | 245 | static struct notifier_block __cpuinitdata cpu_nfb = { |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 246 | .notifier_call = cpu_callback |
| 247 | }; |
| 248 | |
Eduard - Gabriel Munteanu | 7babe8d | 2008-07-25 19:45:11 -0700 | [diff] [blame] | 249 | static int __initdata nosoftlockup; |
| 250 | |
| 251 | static int __init nosoftlockup_setup(char *str) |
| 252 | { |
| 253 | nosoftlockup = 1; |
| 254 | return 1; |
| 255 | } |
| 256 | __setup("nosoftlockup", nosoftlockup_setup); |
| 257 | |
| 258 | static int __init spawn_softlockup_task(void) |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 259 | { |
| 260 | void *cpu = (void *)(long)smp_processor_id(); |
Eduard - Gabriel Munteanu | 7babe8d | 2008-07-25 19:45:11 -0700 | [diff] [blame] | 261 | int err; |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 262 | |
Eduard - Gabriel Munteanu | 7babe8d | 2008-07-25 19:45:11 -0700 | [diff] [blame] | 263 | if (nosoftlockup) |
| 264 | return 0; |
| 265 | |
| 266 | err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu); |
| 267 | if (err == NOTIFY_BAD) { |
| 268 | BUG(); |
| 269 | return 1; |
| 270 | } |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 271 | cpu_callback(&cpu_nfb, CPU_ONLINE, cpu); |
| 272 | register_cpu_notifier(&cpu_nfb); |
| 273 | |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 274 | atomic_notifier_chain_register(&panic_notifier_list, &panic_block); |
Eduard - Gabriel Munteanu | 7babe8d | 2008-07-25 19:45:11 -0700 | [diff] [blame] | 275 | |
| 276 | return 0; |
Ingo Molnar | 8446f1d | 2005-09-06 15:16:27 -0700 | [diff] [blame] | 277 | } |
Eduard - Gabriel Munteanu | 7babe8d | 2008-07-25 19:45:11 -0700 | [diff] [blame] | 278 | early_initcall(spawn_softlockup_task); |