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> | |
22 | ||
23 | #include <asm/s390_ext.h> | |
24 | #include <asm/timer.h> | |
5a489b98 | 25 | #include <asm/irq_regs.h> |
76d4e00a | 26 | #include <asm/cputime.h> |
1da177e4 | 27 | |
1da177e4 | 28 | static ext_int_info_t ext_int_info_timer; |
9cfb9b3c | 29 | |
2b67fc46 | 30 | static DEFINE_PER_CPU(struct vtimer_queue, virt_cpu_timer); |
1da177e4 | 31 | |
9cfb9b3c MS |
32 | DEFINE_PER_CPU(struct s390_idle_data, s390_idle) = { |
33 | .lock = __SPIN_LOCK_UNLOCKED(s390_idle.lock) | |
34 | }; | |
35 | ||
36 | static inline __u64 get_vtimer(void) | |
37 | { | |
38 | __u64 timer; | |
39 | ||
40 | asm volatile("STPT %0" : "=m" (timer)); | |
41 | return timer; | |
42 | } | |
43 | ||
44 | static inline void set_vtimer(__u64 expires) | |
45 | { | |
46 | __u64 timer; | |
47 | ||
48 | asm volatile (" STPT %0\n" /* Store current cpu timer value */ | |
49 | " SPT %1" /* Set new value immediatly afterwards */ | |
50 | : "=m" (timer) : "m" (expires) ); | |
51 | S390_lowcore.system_timer += S390_lowcore.last_update_timer - timer; | |
52 | S390_lowcore.last_update_timer = expires; | |
53 | } | |
54 | ||
1da177e4 LT |
55 | /* |
56 | * Update process times based on virtual cpu times stored by entry.S | |
57 | * to the lowcore fields user_timer, system_timer & steal_clock. | |
58 | */ | |
aa5e97ce | 59 | static void do_account_vtime(struct task_struct *tsk, int hardirq_offset) |
1da177e4 | 60 | { |
aa5e97ce MS |
61 | struct thread_info *ti = task_thread_info(tsk); |
62 | __u64 timer, clock, user, system, steal; | |
1da177e4 LT |
63 | |
64 | timer = S390_lowcore.last_update_timer; | |
65 | clock = S390_lowcore.last_update_clock; | |
66 | asm volatile (" STPT %0\n" /* Store current cpu timer value */ | |
67 | " STCK %1" /* Store current tod clock value */ | |
68 | : "=m" (S390_lowcore.last_update_timer), | |
69 | "=m" (S390_lowcore.last_update_clock) ); | |
70 | S390_lowcore.system_timer += timer - S390_lowcore.last_update_timer; | |
aa5e97ce | 71 | S390_lowcore.steal_timer += S390_lowcore.last_update_clock - clock; |
1da177e4 | 72 | |
aa5e97ce MS |
73 | user = S390_lowcore.user_timer - ti->user_timer; |
74 | S390_lowcore.steal_timer -= user; | |
75 | ti->user_timer = S390_lowcore.user_timer; | |
76 | account_user_time(tsk, user, user); | |
1da177e4 | 77 | |
aa5e97ce MS |
78 | system = S390_lowcore.system_timer - ti->system_timer; |
79 | S390_lowcore.steal_timer -= system; | |
80 | ti->system_timer = S390_lowcore.system_timer; | |
9cfb9b3c | 81 | account_system_time(tsk, hardirq_offset, system, system); |
1da177e4 | 82 | |
aa5e97ce MS |
83 | steal = S390_lowcore.steal_timer; |
84 | if ((s64) steal > 0) { | |
85 | S390_lowcore.steal_timer = 0; | |
9cfb9b3c | 86 | account_steal_time(steal); |
1da177e4 | 87 | } |
1da177e4 LT |
88 | } |
89 | ||
aa5e97ce | 90 | void account_vtime(struct task_struct *prev, struct task_struct *next) |
1f1c12af | 91 | { |
aa5e97ce MS |
92 | struct thread_info *ti; |
93 | ||
94 | do_account_vtime(prev, 0); | |
95 | ti = task_thread_info(prev); | |
96 | ti->user_timer = S390_lowcore.user_timer; | |
97 | ti->system_timer = S390_lowcore.system_timer; | |
98 | ti = task_thread_info(next); | |
99 | S390_lowcore.user_timer = ti->user_timer; | |
100 | S390_lowcore.system_timer = ti->system_timer; | |
101 | } | |
1f1c12af | 102 | |
aa5e97ce MS |
103 | void account_process_tick(struct task_struct *tsk, int user_tick) |
104 | { | |
105 | do_account_vtime(tsk, HARDIRQ_OFFSET); | |
1f1c12af MS |
106 | } |
107 | ||
1da177e4 LT |
108 | /* |
109 | * Update process times based on virtual cpu times stored by entry.S | |
110 | * to the lowcore fields user_timer, system_timer & steal_clock. | |
111 | */ | |
112 | void account_system_vtime(struct task_struct *tsk) | |
113 | { | |
aa5e97ce MS |
114 | struct thread_info *ti = task_thread_info(tsk); |
115 | __u64 timer, system; | |
1da177e4 LT |
116 | |
117 | timer = S390_lowcore.last_update_timer; | |
9cfb9b3c | 118 | S390_lowcore.last_update_timer = get_vtimer(); |
1da177e4 LT |
119 | S390_lowcore.system_timer += timer - S390_lowcore.last_update_timer; |
120 | ||
aa5e97ce MS |
121 | system = S390_lowcore.system_timer - ti->system_timer; |
122 | S390_lowcore.steal_timer -= system; | |
123 | ti->system_timer = S390_lowcore.system_timer; | |
9cfb9b3c | 124 | account_system_time(tsk, 0, system, system); |
1da177e4 | 125 | } |
b0c632db | 126 | EXPORT_SYMBOL_GPL(account_system_vtime); |
1da177e4 | 127 | |
9cfb9b3c | 128 | void vtime_start_cpu(void) |
1da177e4 | 129 | { |
9cfb9b3c | 130 | struct s390_idle_data *idle = &__get_cpu_var(s390_idle); |
6f430924 | 131 | struct vtimer_queue *vq = &__get_cpu_var(virt_cpu_timer); |
9cfb9b3c MS |
132 | __u64 idle_time, expires; |
133 | ||
134 | /* Account time spent with enabled wait psw loaded as idle time. */ | |
135 | idle_time = S390_lowcore.int_clock - idle->idle_enter; | |
136 | account_idle_time(idle_time); | |
b86ccca4 MS |
137 | S390_lowcore.steal_timer += |
138 | idle->idle_enter - S390_lowcore.last_update_clock; | |
9cfb9b3c MS |
139 | S390_lowcore.last_update_clock = S390_lowcore.int_clock; |
140 | ||
141 | /* Account system time spent going idle. */ | |
142 | S390_lowcore.system_timer += S390_lowcore.last_update_timer - vq->idle; | |
143 | S390_lowcore.last_update_timer = S390_lowcore.async_enter_timer; | |
144 | ||
145 | /* Restart vtime CPU timer */ | |
146 | if (vq->do_spt) { | |
147 | /* Program old expire value but first save progress. */ | |
148 | expires = vq->idle - S390_lowcore.async_enter_timer; | |
149 | expires += get_vtimer(); | |
150 | set_vtimer(expires); | |
151 | } else { | |
152 | /* Don't account the CPU timer delta while the cpu was idle. */ | |
153 | vq->elapsed -= vq->idle - S390_lowcore.async_enter_timer; | |
154 | } | |
4b7e0706 | 155 | |
9cfb9b3c MS |
156 | spin_lock(&idle->lock); |
157 | idle->idle_time += idle_time; | |
158 | idle->idle_enter = 0ULL; | |
159 | idle->idle_count++; | |
160 | spin_unlock(&idle->lock); | |
1da177e4 LT |
161 | } |
162 | ||
9cfb9b3c | 163 | void vtime_stop_cpu(void) |
1da177e4 | 164 | { |
9cfb9b3c MS |
165 | struct s390_idle_data *idle = &__get_cpu_var(s390_idle); |
166 | struct vtimer_queue *vq = &__get_cpu_var(virt_cpu_timer); | |
167 | psw_t psw; | |
168 | ||
169 | /* Wait for external, I/O or machine check interrupt. */ | |
170 | psw.mask = psw_kernel_bits | PSW_MASK_WAIT | PSW_MASK_IO | PSW_MASK_EXT; | |
171 | ||
172 | /* Check if the CPU timer needs to be reprogrammed. */ | |
173 | if (vq->do_spt) { | |
174 | __u64 vmax = VTIMER_MAX_SLICE; | |
175 | /* | |
176 | * The inline assembly is equivalent to | |
177 | * vq->idle = get_cpu_timer(); | |
178 | * set_cpu_timer(VTIMER_MAX_SLICE); | |
179 | * idle->idle_enter = get_clock(); | |
180 | * __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT | | |
181 | * PSW_MASK_IO | PSW_MASK_EXT); | |
182 | * The difference is that the inline assembly makes sure that | |
183 | * the last three instruction are stpt, stck and lpsw in that | |
184 | * order. This is done to increase the precision. | |
185 | */ | |
186 | asm volatile( | |
187 | #ifndef CONFIG_64BIT | |
188 | " basr 1,0\n" | |
189 | "0: ahi 1,1f-0b\n" | |
190 | " st 1,4(%2)\n" | |
191 | #else /* CONFIG_64BIT */ | |
192 | " larl 1,1f\n" | |
193 | " stg 1,8(%2)\n" | |
194 | #endif /* CONFIG_64BIT */ | |
195 | " stpt 0(%4)\n" | |
196 | " spt 0(%5)\n" | |
197 | " stck 0(%3)\n" | |
198 | #ifndef CONFIG_64BIT | |
199 | " lpsw 0(%2)\n" | |
200 | #else /* CONFIG_64BIT */ | |
201 | " lpswe 0(%2)\n" | |
202 | #endif /* CONFIG_64BIT */ | |
203 | "1:" | |
204 | : "=m" (idle->idle_enter), "=m" (vq->idle) | |
205 | : "a" (&psw), "a" (&idle->idle_enter), | |
206 | "a" (&vq->idle), "a" (&vmax), "m" (vmax), "m" (psw) | |
207 | : "memory", "cc", "1"); | |
208 | } else { | |
209 | /* | |
210 | * The inline assembly is equivalent to | |
211 | * vq->idle = get_cpu_timer(); | |
212 | * idle->idle_enter = get_clock(); | |
213 | * __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT | | |
214 | * PSW_MASK_IO | PSW_MASK_EXT); | |
215 | * The difference is that the inline assembly makes sure that | |
216 | * the last three instruction are stpt, stck and lpsw in that | |
217 | * order. This is done to increase the precision. | |
218 | */ | |
219 | asm volatile( | |
220 | #ifndef CONFIG_64BIT | |
221 | " basr 1,0\n" | |
222 | "0: ahi 1,1f-0b\n" | |
223 | " st 1,4(%2)\n" | |
224 | #else /* CONFIG_64BIT */ | |
225 | " larl 1,1f\n" | |
226 | " stg 1,8(%2)\n" | |
227 | #endif /* CONFIG_64BIT */ | |
228 | " stpt 0(%4)\n" | |
229 | " stck 0(%3)\n" | |
230 | #ifndef CONFIG_64BIT | |
231 | " lpsw 0(%2)\n" | |
232 | #else /* CONFIG_64BIT */ | |
233 | " lpswe 0(%2)\n" | |
234 | #endif /* CONFIG_64BIT */ | |
235 | "1:" | |
236 | : "=m" (idle->idle_enter), "=m" (vq->idle) | |
237 | : "a" (&psw), "a" (&idle->idle_enter), | |
238 | "a" (&vq->idle), "m" (psw) | |
239 | : "memory", "cc", "1"); | |
1da177e4 | 240 | } |
1da177e4 LT |
241 | } |
242 | ||
e1c80530 MS |
243 | cputime64_t s390_get_idle_time(int cpu) |
244 | { | |
245 | struct s390_idle_data *idle; | |
246 | unsigned long long now, idle_time, idle_enter; | |
247 | ||
248 | idle = &per_cpu(s390_idle, cpu); | |
249 | spin_lock(&idle->lock); | |
250 | now = get_clock(); | |
251 | idle_time = 0; | |
252 | idle_enter = idle->idle_enter; | |
253 | if (idle_enter != 0ULL && idle_enter < now) | |
254 | idle_time = now - idle_enter; | |
255 | spin_unlock(&idle->lock); | |
256 | return idle_time; | |
257 | } | |
258 | ||
1da177e4 LT |
259 | /* |
260 | * Sorted add to a list. List is linear searched until first bigger | |
261 | * element is found. | |
262 | */ | |
263 | static void list_add_sorted(struct vtimer_list *timer, struct list_head *head) | |
264 | { | |
265 | struct vtimer_list *event; | |
266 | ||
267 | list_for_each_entry(event, head, entry) { | |
268 | if (event->expires > timer->expires) { | |
269 | list_add_tail(&timer->entry, &event->entry); | |
270 | return; | |
271 | } | |
272 | } | |
273 | list_add_tail(&timer->entry, head); | |
274 | } | |
275 | ||
276 | /* | |
277 | * Do the callback functions of expired vtimer events. | |
278 | * Called from within the interrupt handler. | |
279 | */ | |
9d0a57cb | 280 | static void do_callbacks(struct list_head *cb_list) |
1da177e4 | 281 | { |
9cfb9b3c | 282 | struct vtimer_queue *vq; |
1da177e4 | 283 | struct vtimer_list *event, *tmp; |
1da177e4 LT |
284 | |
285 | if (list_empty(cb_list)) | |
286 | return; | |
287 | ||
9cfb9b3c | 288 | vq = &__get_cpu_var(virt_cpu_timer); |
1da177e4 LT |
289 | |
290 | list_for_each_entry_safe(event, tmp, cb_list, entry) { | |
9cfb9b3c MS |
291 | list_del_init(&event->entry); |
292 | (event->function)(event->data); | |
293 | if (event->interval) { | |
294 | /* Recharge interval timer */ | |
295 | event->expires = event->interval + vq->elapsed; | |
296 | spin_lock(&vq->lock); | |
297 | list_add_sorted(event, &vq->list); | |
298 | spin_unlock(&vq->lock); | |
1da177e4 LT |
299 | } |
300 | } | |
301 | } | |
302 | ||
303 | /* | |
304 | * Handler for the virtual CPU timer. | |
305 | */ | |
5a489b98 | 306 | static void do_cpu_timer_interrupt(__u16 error_code) |
1da177e4 | 307 | { |
9cfb9b3c | 308 | struct vtimer_queue *vq; |
1da177e4 | 309 | struct vtimer_list *event, *tmp; |
9cfb9b3c MS |
310 | struct list_head cb_list; /* the callback queue */ |
311 | __u64 elapsed, next; | |
1da177e4 LT |
312 | |
313 | INIT_LIST_HEAD(&cb_list); | |
9cfb9b3c | 314 | vq = &__get_cpu_var(virt_cpu_timer); |
1da177e4 LT |
315 | |
316 | /* walk timer list, fire all expired events */ | |
9cfb9b3c MS |
317 | spin_lock(&vq->lock); |
318 | ||
319 | elapsed = vq->elapsed + (vq->timer - S390_lowcore.async_enter_timer); | |
320 | BUG_ON((s64) elapsed < 0); | |
321 | vq->elapsed = 0; | |
322 | list_for_each_entry_safe(event, tmp, &vq->list, entry) { | |
323 | if (event->expires < elapsed) | |
324 | /* move expired timer to the callback queue */ | |
325 | list_move_tail(&event->entry, &cb_list); | |
326 | else | |
327 | event->expires -= elapsed; | |
1da177e4 | 328 | } |
9cfb9b3c MS |
329 | spin_unlock(&vq->lock); |
330 | ||
331 | vq->do_spt = list_empty(&cb_list); | |
9d0a57cb | 332 | do_callbacks(&cb_list); |
1da177e4 LT |
333 | |
334 | /* next event is first in list */ | |
9cfb9b3c MS |
335 | next = VTIMER_MAX_SLICE; |
336 | spin_lock(&vq->lock); | |
337 | if (!list_empty(&vq->list)) { | |
338 | event = list_first_entry(&vq->list, struct vtimer_list, entry); | |
339 | next = event->expires; | |
340 | } else | |
341 | vq->do_spt = 0; | |
342 | spin_unlock(&vq->lock); | |
343 | /* | |
344 | * To improve precision add the time spent by the | |
345 | * interrupt handler to the elapsed time. | |
346 | * Note: CPU timer counts down and we got an interrupt, | |
347 | * the current content is negative | |
348 | */ | |
349 | elapsed = S390_lowcore.async_enter_timer - get_vtimer(); | |
350 | set_vtimer(next - elapsed); | |
351 | vq->timer = next - elapsed; | |
352 | vq->elapsed = elapsed; | |
1da177e4 LT |
353 | } |
354 | ||
355 | void init_virt_timer(struct vtimer_list *timer) | |
356 | { | |
1da177e4 LT |
357 | timer->function = NULL; |
358 | INIT_LIST_HEAD(&timer->entry); | |
1da177e4 LT |
359 | } |
360 | EXPORT_SYMBOL(init_virt_timer); | |
361 | ||
1da177e4 LT |
362 | static inline int vtimer_pending(struct vtimer_list *timer) |
363 | { | |
364 | return (!list_empty(&timer->entry)); | |
365 | } | |
366 | ||
367 | /* | |
368 | * this function should only run on the specified CPU | |
369 | */ | |
370 | static void internal_add_vtimer(struct vtimer_list *timer) | |
371 | { | |
9cfb9b3c | 372 | struct vtimer_queue *vq; |
1da177e4 | 373 | unsigned long flags; |
9cfb9b3c | 374 | __u64 left, expires; |
1da177e4 | 375 | |
9cfb9b3c MS |
376 | vq = &per_cpu(virt_cpu_timer, timer->cpu); |
377 | spin_lock_irqsave(&vq->lock, flags); | |
1da177e4 | 378 | |
ca366a32 | 379 | BUG_ON(timer->cpu != smp_processor_id()); |
1da177e4 | 380 | |
9cfb9b3c MS |
381 | if (list_empty(&vq->list)) { |
382 | /* First timer on this cpu, just program it. */ | |
383 | list_add(&timer->entry, &vq->list); | |
384 | set_vtimer(timer->expires); | |
385 | vq->timer = timer->expires; | |
386 | vq->elapsed = 0; | |
387 | } else { | |
388 | /* Check progress of old timers. */ | |
389 | expires = timer->expires; | |
390 | left = get_vtimer(); | |
391 | if (likely((s64) expires < (s64) left)) { | |
392 | /* The new timer expires before the current timer. */ | |
393 | set_vtimer(expires); | |
394 | vq->elapsed += vq->timer - left; | |
395 | vq->timer = expires; | |
396 | } else { | |
397 | vq->elapsed += vq->timer - left; | |
398 | vq->timer = left; | |
399 | } | |
400 | /* Insert new timer into per cpu list. */ | |
401 | timer->expires += vq->elapsed; | |
402 | list_add_sorted(timer, &vq->list); | |
1da177e4 LT |
403 | } |
404 | ||
9cfb9b3c | 405 | spin_unlock_irqrestore(&vq->lock, flags); |
d6e05edc | 406 | /* release CPU acquired in prepare_vtimer or mod_virt_timer() */ |
1da177e4 LT |
407 | put_cpu(); |
408 | } | |
409 | ||
ca366a32 | 410 | static inline void prepare_vtimer(struct vtimer_list *timer) |
1da177e4 | 411 | { |
ca366a32 MS |
412 | BUG_ON(!timer->function); |
413 | BUG_ON(!timer->expires || timer->expires > VTIMER_MAX_SLICE); | |
414 | BUG_ON(vtimer_pending(timer)); | |
1da177e4 | 415 | timer->cpu = get_cpu(); |
1da177e4 LT |
416 | } |
417 | ||
418 | /* | |
419 | * add_virt_timer - add an oneshot virtual CPU timer | |
420 | */ | |
421 | void add_virt_timer(void *new) | |
422 | { | |
423 | struct vtimer_list *timer; | |
424 | ||
425 | timer = (struct vtimer_list *)new; | |
ca366a32 | 426 | prepare_vtimer(timer); |
1da177e4 LT |
427 | timer->interval = 0; |
428 | internal_add_vtimer(timer); | |
429 | } | |
430 | EXPORT_SYMBOL(add_virt_timer); | |
431 | ||
432 | /* | |
433 | * add_virt_timer_int - add an interval virtual CPU timer | |
434 | */ | |
435 | void add_virt_timer_periodic(void *new) | |
436 | { | |
437 | struct vtimer_list *timer; | |
438 | ||
439 | timer = (struct vtimer_list *)new; | |
ca366a32 | 440 | prepare_vtimer(timer); |
1da177e4 LT |
441 | timer->interval = timer->expires; |
442 | internal_add_vtimer(timer); | |
443 | } | |
444 | EXPORT_SYMBOL(add_virt_timer_periodic); | |
445 | ||
b6ecfa92 | 446 | int __mod_vtimer(struct vtimer_list *timer, __u64 expires, int periodic) |
1da177e4 | 447 | { |
9cfb9b3c | 448 | struct vtimer_queue *vq; |
1da177e4 LT |
449 | unsigned long flags; |
450 | int cpu; | |
451 | ||
ca366a32 MS |
452 | BUG_ON(!timer->function); |
453 | BUG_ON(!expires || expires > VTIMER_MAX_SLICE); | |
1da177e4 | 454 | |
1da177e4 LT |
455 | if (timer->expires == expires && vtimer_pending(timer)) |
456 | return 1; | |
457 | ||
458 | cpu = get_cpu(); | |
9cfb9b3c | 459 | vq = &per_cpu(virt_cpu_timer, cpu); |
1da177e4 LT |
460 | |
461 | /* disable interrupts before test if timer is pending */ | |
9cfb9b3c | 462 | spin_lock_irqsave(&vq->lock, flags); |
1da177e4 LT |
463 | |
464 | /* if timer isn't pending add it on the current CPU */ | |
465 | if (!vtimer_pending(timer)) { | |
9cfb9b3c | 466 | spin_unlock_irqrestore(&vq->lock, flags); |
b6ecfa92 JG |
467 | |
468 | if (periodic) | |
469 | timer->interval = expires; | |
470 | else | |
471 | timer->interval = 0; | |
1da177e4 LT |
472 | timer->expires = expires; |
473 | timer->cpu = cpu; | |
474 | internal_add_vtimer(timer); | |
475 | return 0; | |
476 | } | |
477 | ||
b6ecfa92 JG |
478 | /* check if we run on the right CPU */ |
479 | BUG_ON(timer->cpu != cpu); | |
480 | ||
1da177e4 LT |
481 | list_del_init(&timer->entry); |
482 | timer->expires = expires; | |
b6ecfa92 | 483 | if (periodic) |
1da177e4 LT |
484 | timer->interval = expires; |
485 | ||
486 | /* the timer can't expire anymore so we can release the lock */ | |
9cfb9b3c | 487 | spin_unlock_irqrestore(&vq->lock, flags); |
1da177e4 LT |
488 | internal_add_vtimer(timer); |
489 | return 1; | |
490 | } | |
b6ecfa92 JG |
491 | |
492 | /* | |
493 | * If we change a pending timer the function must be called on the CPU | |
494 | * where the timer is running on. | |
495 | * | |
496 | * returns whether it has modified a pending timer (1) or not (0) | |
497 | */ | |
498 | int mod_virt_timer(struct vtimer_list *timer, __u64 expires) | |
499 | { | |
500 | return __mod_vtimer(timer, expires, 0); | |
501 | } | |
1da177e4 LT |
502 | EXPORT_SYMBOL(mod_virt_timer); |
503 | ||
b6ecfa92 JG |
504 | /* |
505 | * If we change a pending timer the function must be called on the CPU | |
506 | * where the timer is running on. | |
507 | * | |
508 | * returns whether it has modified a pending timer (1) or not (0) | |
509 | */ | |
510 | int mod_virt_timer_periodic(struct vtimer_list *timer, __u64 expires) | |
511 | { | |
512 | return __mod_vtimer(timer, expires, 1); | |
513 | } | |
514 | EXPORT_SYMBOL(mod_virt_timer_periodic); | |
515 | ||
1da177e4 LT |
516 | /* |
517 | * delete a virtual timer | |
518 | * | |
519 | * returns whether the deleted timer was pending (1) or not (0) | |
520 | */ | |
521 | int del_virt_timer(struct vtimer_list *timer) | |
522 | { | |
523 | unsigned long flags; | |
9cfb9b3c | 524 | struct vtimer_queue *vq; |
1da177e4 | 525 | |
1da177e4 LT |
526 | /* check if timer is pending */ |
527 | if (!vtimer_pending(timer)) | |
528 | return 0; | |
529 | ||
9cfb9b3c MS |
530 | vq = &per_cpu(virt_cpu_timer, timer->cpu); |
531 | spin_lock_irqsave(&vq->lock, flags); | |
1da177e4 LT |
532 | |
533 | /* we don't interrupt a running timer, just let it expire! */ | |
534 | list_del_init(&timer->entry); | |
535 | ||
9cfb9b3c | 536 | spin_unlock_irqrestore(&vq->lock, flags); |
1da177e4 LT |
537 | return 1; |
538 | } | |
539 | EXPORT_SYMBOL(del_virt_timer); | |
540 | ||
541 | /* | |
542 | * Start the virtual CPU timer on the current CPU. | |
543 | */ | |
544 | void init_cpu_vtimer(void) | |
545 | { | |
9cfb9b3c | 546 | struct vtimer_queue *vq; |
1da177e4 | 547 | |
9cfb9b3c MS |
548 | /* initialize per cpu vtimer structure */ |
549 | vq = &__get_cpu_var(virt_cpu_timer); | |
550 | INIT_LIST_HEAD(&vq->list); | |
551 | spin_lock_init(&vq->lock); | |
d54853ef MS |
552 | |
553 | /* enable cpu timer interrupts */ | |
554 | __ctl_set_bit(0,10); | |
1da177e4 LT |
555 | } |
556 | ||
1da177e4 LT |
557 | void __init vtime_init(void) |
558 | { | |
559 | /* request the cpu timer external interrupt */ | |
560 | if (register_early_external_interrupt(0x1005, do_cpu_timer_interrupt, | |
561 | &ext_int_info_timer) != 0) | |
562 | panic("Couldn't request external interrupt 0x1005"); | |
563 | ||
d54853ef | 564 | /* Enable cpu timer interrupts on the boot cpu. */ |
1da177e4 LT |
565 | init_cpu_vtimer(); |
566 | } | |
567 |