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-rw-r--r--kernel/watchdog.c50
1 files changed, 26 insertions, 24 deletions
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 6e3c41a4024c..d7ebdf4cea98 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -57,6 +57,8 @@ static int __init hardlockup_panic_setup(char *str)
57{ 57{
58 if (!strncmp(str, "panic", 5)) 58 if (!strncmp(str, "panic", 5))
59 hardlockup_panic = 1; 59 hardlockup_panic = 1;
60 else if (!strncmp(str, "0", 1))
61 no_watchdog = 1;
60 return 1; 62 return 1;
61} 63}
62__setup("nmi_watchdog=", hardlockup_panic_setup); 64__setup("nmi_watchdog=", hardlockup_panic_setup);
@@ -116,12 +118,12 @@ static void __touch_watchdog(void)
116{ 118{
117 int this_cpu = smp_processor_id(); 119 int this_cpu = smp_processor_id();
118 120
119 __get_cpu_var(watchdog_touch_ts) = get_timestamp(this_cpu); 121 __this_cpu_write(watchdog_touch_ts, get_timestamp(this_cpu));
120} 122}
121 123
122void touch_softlockup_watchdog(void) 124void touch_softlockup_watchdog(void)
123{ 125{
124 __raw_get_cpu_var(watchdog_touch_ts) = 0; 126 __this_cpu_write(watchdog_touch_ts, 0);
125} 127}
126EXPORT_SYMBOL(touch_softlockup_watchdog); 128EXPORT_SYMBOL(touch_softlockup_watchdog);
127 129
@@ -165,12 +167,12 @@ void touch_softlockup_watchdog_sync(void)
165/* watchdog detector functions */ 167/* watchdog detector functions */
166static int is_hardlockup(void) 168static int is_hardlockup(void)
167{ 169{
168 unsigned long hrint = __get_cpu_var(hrtimer_interrupts); 170 unsigned long hrint = __this_cpu_read(hrtimer_interrupts);
169 171
170 if (__get_cpu_var(hrtimer_interrupts_saved) == hrint) 172 if (__this_cpu_read(hrtimer_interrupts_saved) == hrint)
171 return 1; 173 return 1;
172 174
173 __get_cpu_var(hrtimer_interrupts_saved) = hrint; 175 __this_cpu_write(hrtimer_interrupts_saved, hrint);
174 return 0; 176 return 0;
175} 177}
176#endif 178#endif
@@ -203,8 +205,8 @@ static void watchdog_overflow_callback(struct perf_event *event, int nmi,
203 /* Ensure the watchdog never gets throttled */ 205 /* Ensure the watchdog never gets throttled */
204 event->hw.interrupts = 0; 206 event->hw.interrupts = 0;
205 207
206 if (__get_cpu_var(watchdog_nmi_touch) == true) { 208 if (__this_cpu_read(watchdog_nmi_touch) == true) {
207 __get_cpu_var(watchdog_nmi_touch) = false; 209 __this_cpu_write(watchdog_nmi_touch, false);
208 return; 210 return;
209 } 211 }
210 212
@@ -218,7 +220,7 @@ static void watchdog_overflow_callback(struct perf_event *event, int nmi,
218 int this_cpu = smp_processor_id(); 220 int this_cpu = smp_processor_id();
219 221
220 /* only print hardlockups once */ 222 /* only print hardlockups once */
221 if (__get_cpu_var(hard_watchdog_warn) == true) 223 if (__this_cpu_read(hard_watchdog_warn) == true)
222 return; 224 return;
223 225
224 if (hardlockup_panic) 226 if (hardlockup_panic)
@@ -226,16 +228,16 @@ static void watchdog_overflow_callback(struct perf_event *event, int nmi,
226 else 228 else
227 WARN(1, "Watchdog detected hard LOCKUP on cpu %d", this_cpu); 229 WARN(1, "Watchdog detected hard LOCKUP on cpu %d", this_cpu);
228 230
229 __get_cpu_var(hard_watchdog_warn) = true; 231 __this_cpu_write(hard_watchdog_warn, true);
230 return; 232 return;
231 } 233 }
232 234
233 __get_cpu_var(hard_watchdog_warn) = false; 235 __this_cpu_write(hard_watchdog_warn, false);
234 return; 236 return;
235} 237}
236static void watchdog_interrupt_count(void) 238static void watchdog_interrupt_count(void)
237{ 239{
238 __get_cpu_var(hrtimer_interrupts)++; 240 __this_cpu_inc(hrtimer_interrupts);
239} 241}
240#else 242#else
241static inline void watchdog_interrupt_count(void) { return; } 243static inline void watchdog_interrupt_count(void) { return; }
@@ -244,7 +246,7 @@ static inline void watchdog_interrupt_count(void) { return; }
244/* watchdog kicker functions */ 246/* watchdog kicker functions */
245static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) 247static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
246{ 248{
247 unsigned long touch_ts = __get_cpu_var(watchdog_touch_ts); 249 unsigned long touch_ts = __this_cpu_read(watchdog_touch_ts);
248 struct pt_regs *regs = get_irq_regs(); 250 struct pt_regs *regs = get_irq_regs();
249 int duration; 251 int duration;
250 252
@@ -252,18 +254,18 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
252 watchdog_interrupt_count(); 254 watchdog_interrupt_count();
253 255
254 /* kick the softlockup detector */ 256 /* kick the softlockup detector */
255 wake_up_process(__get_cpu_var(softlockup_watchdog)); 257 wake_up_process(__this_cpu_read(softlockup_watchdog));
256 258
257 /* .. and repeat */ 259 /* .. and repeat */
258 hrtimer_forward_now(hrtimer, ns_to_ktime(get_sample_period())); 260 hrtimer_forward_now(hrtimer, ns_to_ktime(get_sample_period()));
259 261
260 if (touch_ts == 0) { 262 if (touch_ts == 0) {
261 if (unlikely(__get_cpu_var(softlockup_touch_sync))) { 263 if (unlikely(__this_cpu_read(softlockup_touch_sync))) {
262 /* 264 /*
263 * If the time stamp was touched atomically 265 * If the time stamp was touched atomically
264 * make sure the scheduler tick is up to date. 266 * make sure the scheduler tick is up to date.
265 */ 267 */
266 __get_cpu_var(softlockup_touch_sync) = false; 268 __this_cpu_write(softlockup_touch_sync, false);
267 sched_clock_tick(); 269 sched_clock_tick();
268 } 270 }
269 __touch_watchdog(); 271 __touch_watchdog();
@@ -279,7 +281,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
279 duration = is_softlockup(touch_ts); 281 duration = is_softlockup(touch_ts);
280 if (unlikely(duration)) { 282 if (unlikely(duration)) {
281 /* only warn once */ 283 /* only warn once */
282 if (__get_cpu_var(soft_watchdog_warn) == true) 284 if (__this_cpu_read(soft_watchdog_warn) == true)
283 return HRTIMER_RESTART; 285 return HRTIMER_RESTART;
284 286
285 printk(KERN_ERR "BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n", 287 printk(KERN_ERR "BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n",
@@ -294,9 +296,9 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
294 296
295 if (softlockup_panic) 297 if (softlockup_panic)
296 panic("softlockup: hung tasks"); 298 panic("softlockup: hung tasks");
297 __get_cpu_var(soft_watchdog_warn) = true; 299 __this_cpu_write(soft_watchdog_warn, true);
298 } else 300 } else
299 __get_cpu_var(soft_watchdog_warn) = false; 301 __this_cpu_write(soft_watchdog_warn, false);
300 302
301 return HRTIMER_RESTART; 303 return HRTIMER_RESTART;
302} 304}
@@ -307,7 +309,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
307 */ 309 */
308static int watchdog(void *unused) 310static int watchdog(void *unused)
309{ 311{
310 struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; 312 static struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
311 struct hrtimer *hrtimer = &__raw_get_cpu_var(watchdog_hrtimer); 313 struct hrtimer *hrtimer = &__raw_get_cpu_var(watchdog_hrtimer);
312 314
313 sched_setscheduler(current, SCHED_FIFO, &param); 315 sched_setscheduler(current, SCHED_FIFO, &param);
@@ -364,7 +366,8 @@ static int watchdog_nmi_enable(int cpu)
364 goto out_save; 366 goto out_save;
365 } 367 }
366 368
367 printk(KERN_ERR "NMI watchdog failed to create perf event on cpu%i: %p\n", cpu, event); 369 printk(KERN_ERR "NMI watchdog disabled for cpu%i: unable to create perf event: %ld\n",
370 cpu, PTR_ERR(event));
368 return PTR_ERR(event); 371 return PTR_ERR(event);
369 372
370 /* success path */ 373 /* success path */
@@ -547,13 +550,13 @@ static struct notifier_block __cpuinitdata cpu_nfb = {
547 .notifier_call = cpu_callback 550 .notifier_call = cpu_callback
548}; 551};
549 552
550static int __init spawn_watchdog_task(void) 553void __init lockup_detector_init(void)
551{ 554{
552 void *cpu = (void *)(long)smp_processor_id(); 555 void *cpu = (void *)(long)smp_processor_id();
553 int err; 556 int err;
554 557
555 if (no_watchdog) 558 if (no_watchdog)
556 return 0; 559 return;
557 560
558 err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu); 561 err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
559 WARN_ON(notifier_to_errno(err)); 562 WARN_ON(notifier_to_errno(err));
@@ -561,6 +564,5 @@ static int __init spawn_watchdog_task(void)
561 cpu_callback(&cpu_nfb, CPU_ONLINE, cpu); 564 cpu_callback(&cpu_nfb, CPU_ONLINE, cpu);
562 register_cpu_notifier(&cpu_nfb); 565 register_cpu_notifier(&cpu_nfb);
563 566
564 return 0; 567 return;
565} 568}
566early_initcall(spawn_watchdog_task);