Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * arch/s390/kernel/vtime.c | |
3 | * Virtual cpu timer based timer functions. | |
4 | * | |
5 | * S390 version | |
6 | * Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation | |
7 | * Author(s): Jan Glauber <jan.glauber@de.ibm.com> | |
8 | */ | |
9 | ||
1da177e4 LT |
10 | #include <linux/module.h> |
11 | #include <linux/kernel.h> | |
12 | #include <linux/time.h> | |
13 | #include <linux/delay.h> | |
14 | #include <linux/init.h> | |
15 | #include <linux/smp.h> | |
16 | #include <linux/types.h> | |
17 | #include <linux/timex.h> | |
18 | #include <linux/notifier.h> | |
19 | #include <linux/kernel_stat.h> | |
20 | #include <linux/rcupdate.h> | |
21 | #include <linux/posix-timers.h> | |
39881215 | 22 | #include <linux/cpu.h> |
860dba45 | 23 | #include <linux/kprobes.h> |
1da177e4 LT |
24 | |
25 | #include <asm/s390_ext.h> | |
26 | #include <asm/timer.h> | |
5a489b98 | 27 | #include <asm/irq_regs.h> |
76d4e00a | 28 | #include <asm/cputime.h> |
1da177e4 | 29 | |
2b67fc46 | 30 | static DEFINE_PER_CPU(struct vtimer_queue, virt_cpu_timer); |
1da177e4 | 31 | |
e98bbaaf | 32 | DEFINE_PER_CPU(struct s390_idle_data, s390_idle); |
9cfb9b3c MS |
33 | |
34 | static inline __u64 get_vtimer(void) | |
35 | { | |
36 | __u64 timer; | |
37 | ||
38 | asm volatile("STPT %0" : "=m" (timer)); | |
39 | return timer; | |
40 | } | |
41 | ||
42 | static inline void set_vtimer(__u64 expires) | |
43 | { | |
44 | __u64 timer; | |
45 | ||
46 | asm volatile (" STPT %0\n" /* Store current cpu timer value */ | |
25985edc | 47 | " SPT %1" /* Set new value immediately afterwards */ |
9cfb9b3c MS |
48 | : "=m" (timer) : "m" (expires) ); |
49 | S390_lowcore.system_timer += S390_lowcore.last_update_timer - timer; | |
50 | S390_lowcore.last_update_timer = expires; | |
51 | } | |
52 | ||
1da177e4 LT |
53 | /* |
54 | * Update process times based on virtual cpu times stored by entry.S | |
55 | * to the lowcore fields user_timer, system_timer & steal_clock. | |
56 | */ | |
aa5e97ce | 57 | static void do_account_vtime(struct task_struct *tsk, int hardirq_offset) |
1da177e4 | 58 | { |
aa5e97ce MS |
59 | struct thread_info *ti = task_thread_info(tsk); |
60 | __u64 timer, clock, user, system, steal; | |
1da177e4 LT |
61 | |
62 | timer = S390_lowcore.last_update_timer; | |
63 | clock = S390_lowcore.last_update_clock; | |
64 | asm volatile (" STPT %0\n" /* Store current cpu timer value */ | |
65 | " STCK %1" /* Store current tod clock value */ | |
66 | : "=m" (S390_lowcore.last_update_timer), | |
67 | "=m" (S390_lowcore.last_update_clock) ); | |
68 | S390_lowcore.system_timer += timer - S390_lowcore.last_update_timer; | |
aa5e97ce | 69 | S390_lowcore.steal_timer += S390_lowcore.last_update_clock - clock; |
1da177e4 | 70 | |
aa5e97ce MS |
71 | user = S390_lowcore.user_timer - ti->user_timer; |
72 | S390_lowcore.steal_timer -= user; | |
73 | ti->user_timer = S390_lowcore.user_timer; | |
74 | account_user_time(tsk, user, user); | |
1da177e4 | 75 | |
aa5e97ce MS |
76 | system = S390_lowcore.system_timer - ti->system_timer; |
77 | S390_lowcore.steal_timer -= system; | |
78 | ti->system_timer = S390_lowcore.system_timer; | |
9cfb9b3c | 79 | account_system_time(tsk, hardirq_offset, system, system); |
1da177e4 | 80 | |
aa5e97ce MS |
81 | steal = S390_lowcore.steal_timer; |
82 | if ((s64) steal > 0) { | |
83 | S390_lowcore.steal_timer = 0; | |
9cfb9b3c | 84 | account_steal_time(steal); |
1da177e4 | 85 | } |
1da177e4 LT |
86 | } |
87 | ||
aa5e97ce | 88 | void account_vtime(struct task_struct *prev, struct task_struct *next) |
1f1c12af | 89 | { |
aa5e97ce MS |
90 | struct thread_info *ti; |
91 | ||
92 | do_account_vtime(prev, 0); | |
93 | ti = task_thread_info(prev); | |
94 | ti->user_timer = S390_lowcore.user_timer; | |
95 | ti->system_timer = S390_lowcore.system_timer; | |
96 | ti = task_thread_info(next); | |
97 | S390_lowcore.user_timer = ti->user_timer; | |
98 | S390_lowcore.system_timer = ti->system_timer; | |
99 | } | |
1f1c12af | 100 | |
aa5e97ce MS |
101 | void account_process_tick(struct task_struct *tsk, int user_tick) |
102 | { | |
103 | do_account_vtime(tsk, HARDIRQ_OFFSET); | |
1f1c12af MS |
104 | } |
105 | ||
1da177e4 LT |
106 | /* |
107 | * Update process times based on virtual cpu times stored by entry.S | |
108 | * to the lowcore fields user_timer, system_timer & steal_clock. | |
109 | */ | |
110 | void account_system_vtime(struct task_struct *tsk) | |
111 | { | |
aa5e97ce MS |
112 | struct thread_info *ti = task_thread_info(tsk); |
113 | __u64 timer, system; | |
1da177e4 LT |
114 | |
115 | timer = S390_lowcore.last_update_timer; | |
9cfb9b3c | 116 | S390_lowcore.last_update_timer = get_vtimer(); |
1da177e4 LT |
117 | S390_lowcore.system_timer += timer - S390_lowcore.last_update_timer; |
118 | ||
aa5e97ce MS |
119 | system = S390_lowcore.system_timer - ti->system_timer; |
120 | S390_lowcore.steal_timer -= system; | |
121 | ti->system_timer = S390_lowcore.system_timer; | |
9cfb9b3c | 122 | account_system_time(tsk, 0, system, system); |
1da177e4 | 123 | } |
b0c632db | 124 | EXPORT_SYMBOL_GPL(account_system_vtime); |
1da177e4 | 125 | |
860dba45 | 126 | void __kprobes vtime_start_cpu(__u64 int_clock, __u64 enter_timer) |
1da177e4 | 127 | { |
9cfb9b3c | 128 | struct s390_idle_data *idle = &__get_cpu_var(s390_idle); |
6f430924 | 129 | struct vtimer_queue *vq = &__get_cpu_var(virt_cpu_timer); |
9cfb9b3c MS |
130 | __u64 idle_time, expires; |
131 | ||
6377981f MS |
132 | if (idle->idle_enter == 0ULL) |
133 | return; | |
134 | ||
9cfb9b3c | 135 | /* Account time spent with enabled wait psw loaded as idle time. */ |
6377981f | 136 | idle_time = int_clock - idle->idle_enter; |
9cfb9b3c | 137 | account_idle_time(idle_time); |
b86ccca4 MS |
138 | S390_lowcore.steal_timer += |
139 | idle->idle_enter - S390_lowcore.last_update_clock; | |
6377981f | 140 | S390_lowcore.last_update_clock = int_clock; |
9cfb9b3c MS |
141 | |
142 | /* Account system time spent going idle. */ | |
143 | S390_lowcore.system_timer += S390_lowcore.last_update_timer - vq->idle; | |
6377981f | 144 | S390_lowcore.last_update_timer = enter_timer; |
9cfb9b3c MS |
145 | |
146 | /* Restart vtime CPU timer */ | |
147 | if (vq->do_spt) { | |
148 | /* Program old expire value but first save progress. */ | |
6377981f | 149 | expires = vq->idle - enter_timer; |
9cfb9b3c MS |
150 | expires += get_vtimer(); |
151 | set_vtimer(expires); | |
152 | } else { | |
153 | /* Don't account the CPU timer delta while the cpu was idle. */ | |
6377981f | 154 | vq->elapsed -= vq->idle - enter_timer; |
9cfb9b3c | 155 | } |
4b7e0706 | 156 | |
e98bbaaf MS |
157 | idle->sequence++; |
158 | smp_wmb(); | |
9cfb9b3c MS |
159 | idle->idle_time += idle_time; |
160 | idle->idle_enter = 0ULL; | |
161 | idle->idle_count++; | |
e98bbaaf MS |
162 | smp_wmb(); |
163 | idle->sequence++; | |
1da177e4 LT |
164 | } |
165 | ||
860dba45 | 166 | void __kprobes vtime_stop_cpu(void) |
1da177e4 | 167 | { |
9cfb9b3c MS |
168 | struct s390_idle_data *idle = &__get_cpu_var(s390_idle); |
169 | struct vtimer_queue *vq = &__get_cpu_var(virt_cpu_timer); | |
170 | psw_t psw; | |
171 | ||
172 | /* Wait for external, I/O or machine check interrupt. */ | |
173 | psw.mask = psw_kernel_bits | PSW_MASK_WAIT | PSW_MASK_IO | PSW_MASK_EXT; | |
174 | ||
3c5d92a0 MS |
175 | idle->nohz_delay = 0; |
176 | ||
9cfb9b3c MS |
177 | /* Check if the CPU timer needs to be reprogrammed. */ |
178 | if (vq->do_spt) { | |
179 | __u64 vmax = VTIMER_MAX_SLICE; | |
180 | /* | |
181 | * The inline assembly is equivalent to | |
182 | * vq->idle = get_cpu_timer(); | |
183 | * set_cpu_timer(VTIMER_MAX_SLICE); | |
184 | * idle->idle_enter = get_clock(); | |
185 | * __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT | | |
186 | * PSW_MASK_IO | PSW_MASK_EXT); | |
187 | * The difference is that the inline assembly makes sure that | |
188 | * the last three instruction are stpt, stck and lpsw in that | |
189 | * order. This is done to increase the precision. | |
190 | */ | |
191 | asm volatile( | |
192 | #ifndef CONFIG_64BIT | |
193 | " basr 1,0\n" | |
194 | "0: ahi 1,1f-0b\n" | |
195 | " st 1,4(%2)\n" | |
196 | #else /* CONFIG_64BIT */ | |
197 | " larl 1,1f\n" | |
198 | " stg 1,8(%2)\n" | |
199 | #endif /* CONFIG_64BIT */ | |
200 | " stpt 0(%4)\n" | |
201 | " spt 0(%5)\n" | |
202 | " stck 0(%3)\n" | |
203 | #ifndef CONFIG_64BIT | |
204 | " lpsw 0(%2)\n" | |
205 | #else /* CONFIG_64BIT */ | |
206 | " lpswe 0(%2)\n" | |
207 | #endif /* CONFIG_64BIT */ | |
208 | "1:" | |
209 | : "=m" (idle->idle_enter), "=m" (vq->idle) | |
210 | : "a" (&psw), "a" (&idle->idle_enter), | |
211 | "a" (&vq->idle), "a" (&vmax), "m" (vmax), "m" (psw) | |
212 | : "memory", "cc", "1"); | |
213 | } else { | |
214 | /* | |
215 | * The inline assembly is equivalent to | |
216 | * vq->idle = get_cpu_timer(); | |
217 | * idle->idle_enter = get_clock(); | |
218 | * __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT | | |
219 | * PSW_MASK_IO | PSW_MASK_EXT); | |
220 | * The difference is that the inline assembly makes sure that | |
221 | * the last three instruction are stpt, stck and lpsw in that | |
222 | * order. This is done to increase the precision. | |
223 | */ | |
224 | asm volatile( | |
225 | #ifndef CONFIG_64BIT | |
226 | " basr 1,0\n" | |
227 | "0: ahi 1,1f-0b\n" | |
228 | " st 1,4(%2)\n" | |
229 | #else /* CONFIG_64BIT */ | |
230 | " larl 1,1f\n" | |
231 | " stg 1,8(%2)\n" | |
232 | #endif /* CONFIG_64BIT */ | |
233 | " stpt 0(%4)\n" | |
234 | " stck 0(%3)\n" | |
235 | #ifndef CONFIG_64BIT | |
236 | " lpsw 0(%2)\n" | |
237 | #else /* CONFIG_64BIT */ | |
238 | " lpswe 0(%2)\n" | |
239 | #endif /* CONFIG_64BIT */ | |
240 | "1:" | |
241 | : "=m" (idle->idle_enter), "=m" (vq->idle) | |
242 | : "a" (&psw), "a" (&idle->idle_enter), | |
243 | "a" (&vq->idle), "m" (psw) | |
244 | : "memory", "cc", "1"); | |
1da177e4 | 245 | } |
1da177e4 LT |
246 | } |
247 | ||
e1c80530 MS |
248 | cputime64_t s390_get_idle_time(int cpu) |
249 | { | |
250 | struct s390_idle_data *idle; | |
251 | unsigned long long now, idle_time, idle_enter; | |
e98bbaaf | 252 | unsigned int sequence; |
e1c80530 MS |
253 | |
254 | idle = &per_cpu(s390_idle, cpu); | |
e98bbaaf | 255 | |
e1c80530 | 256 | now = get_clock(); |
e98bbaaf MS |
257 | repeat: |
258 | sequence = idle->sequence; | |
259 | smp_rmb(); | |
260 | if (sequence & 1) | |
261 | goto repeat; | |
e1c80530 MS |
262 | idle_time = 0; |
263 | idle_enter = idle->idle_enter; | |
264 | if (idle_enter != 0ULL && idle_enter < now) | |
265 | idle_time = now - idle_enter; | |
e98bbaaf MS |
266 | smp_rmb(); |
267 | if (idle->sequence != sequence) | |
268 | goto repeat; | |
e1c80530 MS |
269 | return idle_time; |
270 | } | |
271 | ||
1da177e4 LT |
272 | /* |
273 | * Sorted add to a list. List is linear searched until first bigger | |
274 | * element is found. | |
275 | */ | |
276 | static void list_add_sorted(struct vtimer_list *timer, struct list_head *head) | |
277 | { | |
278 | struct vtimer_list *event; | |
279 | ||
280 | list_for_each_entry(event, head, entry) { | |
281 | if (event->expires > timer->expires) { | |
282 | list_add_tail(&timer->entry, &event->entry); | |
283 | return; | |
284 | } | |
285 | } | |
286 | list_add_tail(&timer->entry, head); | |
287 | } | |
288 | ||
289 | /* | |
290 | * Do the callback functions of expired vtimer events. | |
291 | * Called from within the interrupt handler. | |
292 | */ | |
9d0a57cb | 293 | static void do_callbacks(struct list_head *cb_list) |
1da177e4 | 294 | { |
9cfb9b3c | 295 | struct vtimer_queue *vq; |
1da177e4 | 296 | struct vtimer_list *event, *tmp; |
1da177e4 LT |
297 | |
298 | if (list_empty(cb_list)) | |
299 | return; | |
300 | ||
9cfb9b3c | 301 | vq = &__get_cpu_var(virt_cpu_timer); |
1da177e4 LT |
302 | |
303 | list_for_each_entry_safe(event, tmp, cb_list, entry) { | |
9cfb9b3c MS |
304 | list_del_init(&event->entry); |
305 | (event->function)(event->data); | |
306 | if (event->interval) { | |
307 | /* Recharge interval timer */ | |
308 | event->expires = event->interval + vq->elapsed; | |
309 | spin_lock(&vq->lock); | |
310 | list_add_sorted(event, &vq->list); | |
311 | spin_unlock(&vq->lock); | |
1da177e4 LT |
312 | } |
313 | } | |
314 | } | |
315 | ||
316 | /* | |
317 | * Handler for the virtual CPU timer. | |
318 | */ | |
f6649a7e MS |
319 | static void do_cpu_timer_interrupt(unsigned int ext_int_code, |
320 | unsigned int param32, unsigned long param64) | |
1da177e4 | 321 | { |
9cfb9b3c | 322 | struct vtimer_queue *vq; |
1da177e4 | 323 | struct vtimer_list *event, *tmp; |
9cfb9b3c MS |
324 | struct list_head cb_list; /* the callback queue */ |
325 | __u64 elapsed, next; | |
1da177e4 | 326 | |
052ff461 | 327 | kstat_cpu(smp_processor_id()).irqs[EXTINT_TMR]++; |
1da177e4 | 328 | INIT_LIST_HEAD(&cb_list); |
9cfb9b3c | 329 | vq = &__get_cpu_var(virt_cpu_timer); |
1da177e4 LT |
330 | |
331 | /* walk timer list, fire all expired events */ | |
9cfb9b3c MS |
332 | spin_lock(&vq->lock); |
333 | ||
334 | elapsed = vq->elapsed + (vq->timer - S390_lowcore.async_enter_timer); | |
335 | BUG_ON((s64) elapsed < 0); | |
336 | vq->elapsed = 0; | |
337 | list_for_each_entry_safe(event, tmp, &vq->list, entry) { | |
338 | if (event->expires < elapsed) | |
339 | /* move expired timer to the callback queue */ | |
340 | list_move_tail(&event->entry, &cb_list); | |
341 | else | |
342 | event->expires -= elapsed; | |
1da177e4 | 343 | } |
9cfb9b3c MS |
344 | spin_unlock(&vq->lock); |
345 | ||
346 | vq->do_spt = list_empty(&cb_list); | |
9d0a57cb | 347 | do_callbacks(&cb_list); |
1da177e4 LT |
348 | |
349 | /* next event is first in list */ | |
9cfb9b3c MS |
350 | next = VTIMER_MAX_SLICE; |
351 | spin_lock(&vq->lock); | |
352 | if (!list_empty(&vq->list)) { | |
353 | event = list_first_entry(&vq->list, struct vtimer_list, entry); | |
354 | next = event->expires; | |
355 | } else | |
356 | vq->do_spt = 0; | |
357 | spin_unlock(&vq->lock); | |
358 | /* | |
359 | * To improve precision add the time spent by the | |
360 | * interrupt handler to the elapsed time. | |
361 | * Note: CPU timer counts down and we got an interrupt, | |
362 | * the current content is negative | |
363 | */ | |
364 | elapsed = S390_lowcore.async_enter_timer - get_vtimer(); | |
365 | set_vtimer(next - elapsed); | |
366 | vq->timer = next - elapsed; | |
367 | vq->elapsed = elapsed; | |
1da177e4 LT |
368 | } |
369 | ||
370 | void init_virt_timer(struct vtimer_list *timer) | |
371 | { | |
1da177e4 LT |
372 | timer->function = NULL; |
373 | INIT_LIST_HEAD(&timer->entry); | |
1da177e4 LT |
374 | } |
375 | EXPORT_SYMBOL(init_virt_timer); | |
376 | ||
1da177e4 LT |
377 | static inline int vtimer_pending(struct vtimer_list *timer) |
378 | { | |
379 | return (!list_empty(&timer->entry)); | |
380 | } | |
381 | ||
382 | /* | |
383 | * this function should only run on the specified CPU | |
384 | */ | |
385 | static void internal_add_vtimer(struct vtimer_list *timer) | |
386 | { | |
9cfb9b3c | 387 | struct vtimer_queue *vq; |
1da177e4 | 388 | unsigned long flags; |
9cfb9b3c | 389 | __u64 left, expires; |
1da177e4 | 390 | |
9cfb9b3c MS |
391 | vq = &per_cpu(virt_cpu_timer, timer->cpu); |
392 | spin_lock_irqsave(&vq->lock, flags); | |
1da177e4 | 393 | |
ca366a32 | 394 | BUG_ON(timer->cpu != smp_processor_id()); |
1da177e4 | 395 | |
9cfb9b3c MS |
396 | if (list_empty(&vq->list)) { |
397 | /* First timer on this cpu, just program it. */ | |
398 | list_add(&timer->entry, &vq->list); | |
399 | set_vtimer(timer->expires); | |
400 | vq->timer = timer->expires; | |
401 | vq->elapsed = 0; | |
402 | } else { | |
403 | /* Check progress of old timers. */ | |
404 | expires = timer->expires; | |
405 | left = get_vtimer(); | |
406 | if (likely((s64) expires < (s64) left)) { | |
407 | /* The new timer expires before the current timer. */ | |
408 | set_vtimer(expires); | |
409 | vq->elapsed += vq->timer - left; | |
410 | vq->timer = expires; | |
411 | } else { | |
412 | vq->elapsed += vq->timer - left; | |
413 | vq->timer = left; | |
414 | } | |
415 | /* Insert new timer into per cpu list. */ | |
416 | timer->expires += vq->elapsed; | |
417 | list_add_sorted(timer, &vq->list); | |
1da177e4 LT |
418 | } |
419 | ||
9cfb9b3c | 420 | spin_unlock_irqrestore(&vq->lock, flags); |
d6e05edc | 421 | /* release CPU acquired in prepare_vtimer or mod_virt_timer() */ |
1da177e4 LT |
422 | put_cpu(); |
423 | } | |
424 | ||
ca366a32 | 425 | static inline void prepare_vtimer(struct vtimer_list *timer) |
1da177e4 | 426 | { |
ca366a32 MS |
427 | BUG_ON(!timer->function); |
428 | BUG_ON(!timer->expires || timer->expires > VTIMER_MAX_SLICE); | |
429 | BUG_ON(vtimer_pending(timer)); | |
1da177e4 | 430 | timer->cpu = get_cpu(); |
1da177e4 LT |
431 | } |
432 | ||
433 | /* | |
434 | * add_virt_timer - add an oneshot virtual CPU timer | |
435 | */ | |
436 | void add_virt_timer(void *new) | |
437 | { | |
438 | struct vtimer_list *timer; | |
439 | ||
440 | timer = (struct vtimer_list *)new; | |
ca366a32 | 441 | prepare_vtimer(timer); |
1da177e4 LT |
442 | timer->interval = 0; |
443 | internal_add_vtimer(timer); | |
444 | } | |
445 | EXPORT_SYMBOL(add_virt_timer); | |
446 | ||
447 | /* | |
448 | * add_virt_timer_int - add an interval virtual CPU timer | |
449 | */ | |
450 | void add_virt_timer_periodic(void *new) | |
451 | { | |
452 | struct vtimer_list *timer; | |
453 | ||
454 | timer = (struct vtimer_list *)new; | |
ca366a32 | 455 | prepare_vtimer(timer); |
1da177e4 LT |
456 | timer->interval = timer->expires; |
457 | internal_add_vtimer(timer); | |
458 | } | |
459 | EXPORT_SYMBOL(add_virt_timer_periodic); | |
460 | ||
b6ecfa92 | 461 | int __mod_vtimer(struct vtimer_list *timer, __u64 expires, int periodic) |
1da177e4 | 462 | { |
9cfb9b3c | 463 | struct vtimer_queue *vq; |
1da177e4 LT |
464 | unsigned long flags; |
465 | int cpu; | |
466 | ||
ca366a32 MS |
467 | BUG_ON(!timer->function); |
468 | BUG_ON(!expires || expires > VTIMER_MAX_SLICE); | |
1da177e4 | 469 | |
1da177e4 LT |
470 | if (timer->expires == expires && vtimer_pending(timer)) |
471 | return 1; | |
472 | ||
473 | cpu = get_cpu(); | |
9cfb9b3c | 474 | vq = &per_cpu(virt_cpu_timer, cpu); |
1da177e4 LT |
475 | |
476 | /* disable interrupts before test if timer is pending */ | |
9cfb9b3c | 477 | spin_lock_irqsave(&vq->lock, flags); |
1da177e4 LT |
478 | |
479 | /* if timer isn't pending add it on the current CPU */ | |
480 | if (!vtimer_pending(timer)) { | |
9cfb9b3c | 481 | spin_unlock_irqrestore(&vq->lock, flags); |
b6ecfa92 JG |
482 | |
483 | if (periodic) | |
484 | timer->interval = expires; | |
485 | else | |
486 | timer->interval = 0; | |
1da177e4 LT |
487 | timer->expires = expires; |
488 | timer->cpu = cpu; | |
489 | internal_add_vtimer(timer); | |
490 | return 0; | |
491 | } | |
492 | ||
b6ecfa92 JG |
493 | /* check if we run on the right CPU */ |
494 | BUG_ON(timer->cpu != cpu); | |
495 | ||
1da177e4 LT |
496 | list_del_init(&timer->entry); |
497 | timer->expires = expires; | |
b6ecfa92 | 498 | if (periodic) |
1da177e4 LT |
499 | timer->interval = expires; |
500 | ||
501 | /* the timer can't expire anymore so we can release the lock */ | |
9cfb9b3c | 502 | spin_unlock_irqrestore(&vq->lock, flags); |
1da177e4 LT |
503 | internal_add_vtimer(timer); |
504 | return 1; | |
505 | } | |
b6ecfa92 JG |
506 | |
507 | /* | |
508 | * If we change a pending timer the function must be called on the CPU | |
509 | * where the timer is running on. | |
510 | * | |
511 | * returns whether it has modified a pending timer (1) or not (0) | |
512 | */ | |
513 | int mod_virt_timer(struct vtimer_list *timer, __u64 expires) | |
514 | { | |
515 | return __mod_vtimer(timer, expires, 0); | |
516 | } | |
1da177e4 LT |
517 | EXPORT_SYMBOL(mod_virt_timer); |
518 | ||
b6ecfa92 JG |
519 | /* |
520 | * If we change a pending timer the function must be called on the CPU | |
521 | * where the timer is running on. | |
522 | * | |
523 | * returns whether it has modified a pending timer (1) or not (0) | |
524 | */ | |
525 | int mod_virt_timer_periodic(struct vtimer_list *timer, __u64 expires) | |
526 | { | |
527 | return __mod_vtimer(timer, expires, 1); | |
528 | } | |
529 | EXPORT_SYMBOL(mod_virt_timer_periodic); | |
530 | ||
1da177e4 LT |
531 | /* |
532 | * delete a virtual timer | |
533 | * | |
534 | * returns whether the deleted timer was pending (1) or not (0) | |
535 | */ | |
536 | int del_virt_timer(struct vtimer_list *timer) | |
537 | { | |
538 | unsigned long flags; | |
9cfb9b3c | 539 | struct vtimer_queue *vq; |
1da177e4 | 540 | |
1da177e4 LT |
541 | /* check if timer is pending */ |
542 | if (!vtimer_pending(timer)) | |
543 | return 0; | |
544 | ||
9cfb9b3c MS |
545 | vq = &per_cpu(virt_cpu_timer, timer->cpu); |
546 | spin_lock_irqsave(&vq->lock, flags); | |
1da177e4 LT |
547 | |
548 | /* we don't interrupt a running timer, just let it expire! */ | |
549 | list_del_init(&timer->entry); | |
550 | ||
9cfb9b3c | 551 | spin_unlock_irqrestore(&vq->lock, flags); |
1da177e4 LT |
552 | return 1; |
553 | } | |
554 | EXPORT_SYMBOL(del_virt_timer); | |
555 | ||
556 | /* | |
557 | * Start the virtual CPU timer on the current CPU. | |
558 | */ | |
559 | void init_cpu_vtimer(void) | |
560 | { | |
9cfb9b3c | 561 | struct vtimer_queue *vq; |
1da177e4 | 562 | |
9cfb9b3c MS |
563 | /* initialize per cpu vtimer structure */ |
564 | vq = &__get_cpu_var(virt_cpu_timer); | |
565 | INIT_LIST_HEAD(&vq->list); | |
566 | spin_lock_init(&vq->lock); | |
d54853ef MS |
567 | |
568 | /* enable cpu timer interrupts */ | |
569 | __ctl_set_bit(0,10); | |
1da177e4 LT |
570 | } |
571 | ||
39881215 HC |
572 | static int __cpuinit s390_nohz_notify(struct notifier_block *self, |
573 | unsigned long action, void *hcpu) | |
574 | { | |
575 | struct s390_idle_data *idle; | |
576 | long cpu = (long) hcpu; | |
577 | ||
578 | idle = &per_cpu(s390_idle, cpu); | |
579 | switch (action) { | |
580 | case CPU_DYING: | |
581 | case CPU_DYING_FROZEN: | |
582 | idle->nohz_delay = 0; | |
583 | default: | |
584 | break; | |
585 | } | |
586 | return NOTIFY_OK; | |
587 | } | |
588 | ||
1da177e4 LT |
589 | void __init vtime_init(void) |
590 | { | |
591 | /* request the cpu timer external interrupt */ | |
d7d1104f | 592 | if (register_external_interrupt(0x1005, do_cpu_timer_interrupt)) |
1da177e4 LT |
593 | panic("Couldn't request external interrupt 0x1005"); |
594 | ||
d54853ef | 595 | /* Enable cpu timer interrupts on the boot cpu. */ |
1da177e4 | 596 | init_cpu_vtimer(); |
39881215 | 597 | cpu_notifier(s390_nohz_notify, 0); |
1da177e4 LT |
598 | } |
599 |