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Commit | Line | Data |
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15c84731 JF |
1 | /* |
2 | * Xen time implementation. | |
3 | * | |
4 | * This is implemented in terms of a clocksource driver which uses | |
5 | * the hypervisor clock as a nanosecond timebase, and a clockevent | |
6 | * driver which uses the hypervisor's timer mechanism. | |
7 | * | |
8 | * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 | |
9 | */ | |
10 | #include <linux/kernel.h> | |
11 | #include <linux/interrupt.h> | |
12 | #include <linux/clocksource.h> | |
13 | #include <linux/clockchips.h> | |
f91a8b44 | 14 | #include <linux/kernel_stat.h> |
15c84731 JF |
15 | |
16 | #include <asm/xen/hypervisor.h> | |
17 | #include <asm/xen/hypercall.h> | |
18 | ||
19 | #include <xen/events.h> | |
20 | #include <xen/interface/xen.h> | |
21 | #include <xen/interface/vcpu.h> | |
22 | ||
23 | #include "xen-ops.h" | |
24 | ||
25 | #define XEN_SHIFT 22 | |
26 | ||
27 | /* Xen may fire a timer up to this many ns early */ | |
28 | #define TIMER_SLOP 100000 | |
f91a8b44 | 29 | #define NS_PER_TICK (1000000000LL / HZ) |
15c84731 | 30 | |
ab550288 JF |
31 | static cycle_t xen_clocksource_read(void); |
32 | ||
15c84731 JF |
33 | /* These are perodically updated in shared_info, and then copied here. */ |
34 | struct shadow_time_info { | |
35 | u64 tsc_timestamp; /* TSC at last update of time vals. */ | |
36 | u64 system_timestamp; /* Time, in nanosecs, since boot. */ | |
37 | u32 tsc_to_nsec_mul; | |
38 | int tsc_shift; | |
39 | u32 version; | |
40 | }; | |
41 | ||
42 | static DEFINE_PER_CPU(struct shadow_time_info, shadow_time); | |
43 | ||
f91a8b44 JF |
44 | /* runstate info updated by Xen */ |
45 | static DEFINE_PER_CPU(struct vcpu_runstate_info, runstate); | |
46 | ||
47 | /* snapshots of runstate info */ | |
48 | static DEFINE_PER_CPU(struct vcpu_runstate_info, runstate_snapshot); | |
49 | ||
50 | /* unused ns of stolen and blocked time */ | |
51 | static DEFINE_PER_CPU(u64, residual_stolen); | |
52 | static DEFINE_PER_CPU(u64, residual_blocked); | |
53 | ||
54 | /* return an consistent snapshot of 64-bit time/counter value */ | |
55 | static u64 get64(const u64 *p) | |
56 | { | |
57 | u64 ret; | |
58 | ||
59 | if (BITS_PER_LONG < 64) { | |
60 | u32 *p32 = (u32 *)p; | |
61 | u32 h, l; | |
62 | ||
63 | /* | |
64 | * Read high then low, and then make sure high is | |
65 | * still the same; this will only loop if low wraps | |
66 | * and carries into high. | |
67 | * XXX some clean way to make this endian-proof? | |
68 | */ | |
69 | do { | |
70 | h = p32[1]; | |
71 | barrier(); | |
72 | l = p32[0]; | |
73 | barrier(); | |
74 | } while (p32[1] != h); | |
75 | ||
76 | ret = (((u64)h) << 32) | l; | |
77 | } else | |
78 | ret = *p; | |
79 | ||
80 | return ret; | |
81 | } | |
82 | ||
83 | /* | |
84 | * Runstate accounting | |
85 | */ | |
86 | static void get_runstate_snapshot(struct vcpu_runstate_info *res) | |
87 | { | |
88 | u64 state_time; | |
89 | struct vcpu_runstate_info *state; | |
90 | ||
f120f13e | 91 | BUG_ON(preemptible()); |
f91a8b44 JF |
92 | |
93 | state = &__get_cpu_var(runstate); | |
94 | ||
95 | /* | |
96 | * The runstate info is always updated by the hypervisor on | |
97 | * the current CPU, so there's no need to use anything | |
98 | * stronger than a compiler barrier when fetching it. | |
99 | */ | |
100 | do { | |
101 | state_time = get64(&state->state_entry_time); | |
102 | barrier(); | |
103 | *res = *state; | |
104 | barrier(); | |
105 | } while (get64(&state->state_entry_time) != state_time); | |
f91a8b44 JF |
106 | } |
107 | ||
108 | static void setup_runstate_info(int cpu) | |
109 | { | |
110 | struct vcpu_register_runstate_memory_area area; | |
111 | ||
112 | area.addr.v = &per_cpu(runstate, cpu); | |
113 | ||
114 | if (HYPERVISOR_vcpu_op(VCPUOP_register_runstate_memory_area, | |
115 | cpu, &area)) | |
116 | BUG(); | |
117 | } | |
118 | ||
119 | static void do_stolen_accounting(void) | |
120 | { | |
121 | struct vcpu_runstate_info state; | |
122 | struct vcpu_runstate_info *snap; | |
123 | s64 blocked, runnable, offline, stolen; | |
124 | cputime_t ticks; | |
125 | ||
126 | get_runstate_snapshot(&state); | |
127 | ||
128 | WARN_ON(state.state != RUNSTATE_running); | |
129 | ||
130 | snap = &__get_cpu_var(runstate_snapshot); | |
131 | ||
132 | /* work out how much time the VCPU has not been runn*ing* */ | |
133 | blocked = state.time[RUNSTATE_blocked] - snap->time[RUNSTATE_blocked]; | |
134 | runnable = state.time[RUNSTATE_runnable] - snap->time[RUNSTATE_runnable]; | |
135 | offline = state.time[RUNSTATE_offline] - snap->time[RUNSTATE_offline]; | |
136 | ||
137 | *snap = state; | |
138 | ||
139 | /* Add the appropriate number of ticks of stolen time, | |
140 | including any left-overs from last time. Passing NULL to | |
141 | account_steal_time accounts the time as stolen. */ | |
142 | stolen = runnable + offline + __get_cpu_var(residual_stolen); | |
143 | ||
144 | if (stolen < 0) | |
145 | stolen = 0; | |
146 | ||
147 | ticks = 0; | |
148 | while (stolen >= NS_PER_TICK) { | |
149 | ticks++; | |
150 | stolen -= NS_PER_TICK; | |
151 | } | |
152 | __get_cpu_var(residual_stolen) = stolen; | |
153 | account_steal_time(NULL, ticks); | |
154 | ||
155 | /* Add the appropriate number of ticks of blocked time, | |
156 | including any left-overs from last time. Passing idle to | |
157 | account_steal_time accounts the time as idle/wait. */ | |
158 | blocked += __get_cpu_var(residual_blocked); | |
159 | ||
160 | if (blocked < 0) | |
161 | blocked = 0; | |
162 | ||
163 | ticks = 0; | |
164 | while (blocked >= NS_PER_TICK) { | |
165 | ticks++; | |
166 | blocked -= NS_PER_TICK; | |
167 | } | |
168 | __get_cpu_var(residual_blocked) = blocked; | |
169 | account_steal_time(idle_task(smp_processor_id()), ticks); | |
170 | } | |
171 | ||
ab550288 JF |
172 | /* |
173 | * Xen sched_clock implementation. Returns the number of unstolen | |
174 | * nanoseconds, which is nanoseconds the VCPU spent in RUNNING+BLOCKED | |
175 | * states. | |
176 | */ | |
177 | unsigned long long xen_sched_clock(void) | |
178 | { | |
179 | struct vcpu_runstate_info state; | |
f120f13e JF |
180 | cycle_t now; |
181 | u64 ret; | |
ab550288 JF |
182 | s64 offset; |
183 | ||
f120f13e JF |
184 | /* |
185 | * Ideally sched_clock should be called on a per-cpu basis | |
186 | * anyway, so preempt should already be disabled, but that's | |
187 | * not current practice at the moment. | |
188 | */ | |
189 | preempt_disable(); | |
190 | ||
191 | now = xen_clocksource_read(); | |
192 | ||
ab550288 JF |
193 | get_runstate_snapshot(&state); |
194 | ||
195 | WARN_ON(state.state != RUNSTATE_running); | |
196 | ||
197 | offset = now - state.state_entry_time; | |
198 | if (offset < 0) | |
199 | offset = 0; | |
200 | ||
f120f13e | 201 | ret = state.time[RUNSTATE_blocked] + |
ab550288 JF |
202 | state.time[RUNSTATE_running] + |
203 | offset; | |
f120f13e JF |
204 | |
205 | preempt_enable(); | |
206 | ||
207 | return ret; | |
ab550288 | 208 | } |
f91a8b44 JF |
209 | |
210 | ||
211 | /* Get the CPU speed from Xen */ | |
15c84731 JF |
212 | unsigned long xen_cpu_khz(void) |
213 | { | |
214 | u64 cpu_khz = 1000000ULL << 32; | |
215 | const struct vcpu_time_info *info = | |
216 | &HYPERVISOR_shared_info->vcpu_info[0].time; | |
217 | ||
218 | do_div(cpu_khz, info->tsc_to_system_mul); | |
219 | if (info->tsc_shift < 0) | |
220 | cpu_khz <<= -info->tsc_shift; | |
221 | else | |
222 | cpu_khz >>= info->tsc_shift; | |
223 | ||
224 | return cpu_khz; | |
225 | } | |
226 | ||
227 | /* | |
228 | * Reads a consistent set of time-base values from Xen, into a shadow data | |
229 | * area. | |
230 | */ | |
f91a8b44 | 231 | static unsigned get_time_values_from_xen(void) |
15c84731 JF |
232 | { |
233 | struct vcpu_time_info *src; | |
234 | struct shadow_time_info *dst; | |
235 | ||
15c84731 JF |
236 | /* src is shared memory with the hypervisor, so we need to |
237 | make sure we get a consistent snapshot, even in the face of | |
238 | being preempted. */ | |
239 | src = &__get_cpu_var(xen_vcpu)->time; | |
240 | dst = &__get_cpu_var(shadow_time); | |
241 | ||
242 | do { | |
243 | dst->version = src->version; | |
244 | rmb(); /* fetch version before data */ | |
245 | dst->tsc_timestamp = src->tsc_timestamp; | |
246 | dst->system_timestamp = src->system_time; | |
247 | dst->tsc_to_nsec_mul = src->tsc_to_system_mul; | |
248 | dst->tsc_shift = src->tsc_shift; | |
249 | rmb(); /* test version after fetching data */ | |
250 | } while ((src->version & 1) | (dst->version ^ src->version)); | |
251 | ||
f91a8b44 | 252 | return dst->version; |
15c84731 JF |
253 | } |
254 | ||
255 | /* | |
256 | * Scale a 64-bit delta by scaling and multiplying by a 32-bit fraction, | |
257 | * yielding a 64-bit result. | |
258 | */ | |
259 | static inline u64 scale_delta(u64 delta, u32 mul_frac, int shift) | |
260 | { | |
261 | u64 product; | |
262 | #ifdef __i386__ | |
263 | u32 tmp1, tmp2; | |
264 | #endif | |
265 | ||
266 | if (shift < 0) | |
267 | delta >>= -shift; | |
268 | else | |
269 | delta <<= shift; | |
270 | ||
271 | #ifdef __i386__ | |
272 | __asm__ ( | |
273 | "mul %5 ; " | |
274 | "mov %4,%%eax ; " | |
275 | "mov %%edx,%4 ; " | |
276 | "mul %5 ; " | |
277 | "xor %5,%5 ; " | |
278 | "add %4,%%eax ; " | |
279 | "adc %5,%%edx ; " | |
280 | : "=A" (product), "=r" (tmp1), "=r" (tmp2) | |
281 | : "a" ((u32)delta), "1" ((u32)(delta >> 32)), "2" (mul_frac) ); | |
282 | #elif __x86_64__ | |
283 | __asm__ ( | |
284 | "mul %%rdx ; shrd $32,%%rdx,%%rax" | |
285 | : "=a" (product) : "0" (delta), "d" ((u64)mul_frac) ); | |
286 | #else | |
287 | #error implement me! | |
288 | #endif | |
289 | ||
290 | return product; | |
291 | } | |
292 | ||
293 | static u64 get_nsec_offset(struct shadow_time_info *shadow) | |
294 | { | |
295 | u64 now, delta; | |
f91a8b44 | 296 | now = native_read_tsc(); |
15c84731 JF |
297 | delta = now - shadow->tsc_timestamp; |
298 | return scale_delta(delta, shadow->tsc_to_nsec_mul, shadow->tsc_shift); | |
299 | } | |
300 | ||
ab550288 | 301 | static cycle_t xen_clocksource_read(void) |
15c84731 JF |
302 | { |
303 | struct shadow_time_info *shadow = &get_cpu_var(shadow_time); | |
304 | cycle_t ret; | |
f91a8b44 | 305 | unsigned version; |
15c84731 | 306 | |
f91a8b44 JF |
307 | do { |
308 | version = get_time_values_from_xen(); | |
309 | barrier(); | |
310 | ret = shadow->system_timestamp + get_nsec_offset(shadow); | |
311 | barrier(); | |
312 | } while (version != __get_cpu_var(xen_vcpu)->time.version); | |
15c84731 JF |
313 | |
314 | put_cpu_var(shadow_time); | |
315 | ||
316 | return ret; | |
317 | } | |
318 | ||
319 | static void xen_read_wallclock(struct timespec *ts) | |
320 | { | |
321 | const struct shared_info *s = HYPERVISOR_shared_info; | |
322 | u32 version; | |
323 | u64 delta; | |
324 | struct timespec now; | |
325 | ||
326 | /* get wallclock at system boot */ | |
327 | do { | |
328 | version = s->wc_version; | |
329 | rmb(); /* fetch version before time */ | |
330 | now.tv_sec = s->wc_sec; | |
331 | now.tv_nsec = s->wc_nsec; | |
332 | rmb(); /* fetch time before checking version */ | |
333 | } while ((s->wc_version & 1) | (version ^ s->wc_version)); | |
334 | ||
335 | delta = xen_clocksource_read(); /* time since system boot */ | |
336 | delta += now.tv_sec * (u64)NSEC_PER_SEC + now.tv_nsec; | |
337 | ||
338 | now.tv_nsec = do_div(delta, NSEC_PER_SEC); | |
339 | now.tv_sec = delta; | |
340 | ||
341 | set_normalized_timespec(ts, now.tv_sec, now.tv_nsec); | |
342 | } | |
343 | ||
344 | unsigned long xen_get_wallclock(void) | |
345 | { | |
346 | struct timespec ts; | |
347 | ||
348 | xen_read_wallclock(&ts); | |
349 | ||
350 | return ts.tv_sec; | |
351 | } | |
352 | ||
353 | int xen_set_wallclock(unsigned long now) | |
354 | { | |
355 | /* do nothing for domU */ | |
356 | return -1; | |
357 | } | |
358 | ||
359 | static struct clocksource xen_clocksource __read_mostly = { | |
360 | .name = "xen", | |
361 | .rating = 400, | |
362 | .read = xen_clocksource_read, | |
363 | .mask = ~0, | |
364 | .mult = 1<<XEN_SHIFT, /* time directly in nanoseconds */ | |
365 | .shift = XEN_SHIFT, | |
366 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
367 | }; | |
368 | ||
369 | /* | |
370 | Xen clockevent implementation | |
371 | ||
372 | Xen has two clockevent implementations: | |
373 | ||
374 | The old timer_op one works with all released versions of Xen prior | |
375 | to version 3.0.4. This version of the hypervisor provides a | |
376 | single-shot timer with nanosecond resolution. However, sharing the | |
377 | same event channel is a 100Hz tick which is delivered while the | |
378 | vcpu is running. We don't care about or use this tick, but it will | |
379 | cause the core time code to think the timer fired too soon, and | |
380 | will end up resetting it each time. It could be filtered, but | |
381 | doing so has complications when the ktime clocksource is not yet | |
382 | the xen clocksource (ie, at boot time). | |
383 | ||
384 | The new vcpu_op-based timer interface allows the tick timer period | |
385 | to be changed or turned off. The tick timer is not useful as a | |
386 | periodic timer because events are only delivered to running vcpus. | |
387 | The one-shot timer can report when a timeout is in the past, so | |
388 | set_next_event is capable of returning -ETIME when appropriate. | |
389 | This interface is used when available. | |
390 | */ | |
391 | ||
392 | ||
393 | /* | |
394 | Get a hypervisor absolute time. In theory we could maintain an | |
395 | offset between the kernel's time and the hypervisor's time, and | |
396 | apply that to a kernel's absolute timeout. Unfortunately the | |
397 | hypervisor and kernel times can drift even if the kernel is using | |
398 | the Xen clocksource, because ntp can warp the kernel's clocksource. | |
399 | */ | |
400 | static s64 get_abs_timeout(unsigned long delta) | |
401 | { | |
402 | return xen_clocksource_read() + delta; | |
403 | } | |
404 | ||
405 | static void xen_timerop_set_mode(enum clock_event_mode mode, | |
406 | struct clock_event_device *evt) | |
407 | { | |
408 | switch (mode) { | |
409 | case CLOCK_EVT_MODE_PERIODIC: | |
410 | /* unsupported */ | |
411 | WARN_ON(1); | |
412 | break; | |
413 | ||
414 | case CLOCK_EVT_MODE_ONESHOT: | |
415 | break; | |
416 | ||
417 | case CLOCK_EVT_MODE_UNUSED: | |
418 | case CLOCK_EVT_MODE_SHUTDOWN: | |
419 | HYPERVISOR_set_timer_op(0); /* cancel timeout */ | |
420 | break; | |
421 | } | |
422 | } | |
423 | ||
424 | static int xen_timerop_set_next_event(unsigned long delta, | |
425 | struct clock_event_device *evt) | |
426 | { | |
427 | WARN_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT); | |
428 | ||
429 | if (HYPERVISOR_set_timer_op(get_abs_timeout(delta)) < 0) | |
430 | BUG(); | |
431 | ||
432 | /* We may have missed the deadline, but there's no real way of | |
433 | knowing for sure. If the event was in the past, then we'll | |
434 | get an immediate interrupt. */ | |
435 | ||
436 | return 0; | |
437 | } | |
438 | ||
439 | static const struct clock_event_device xen_timerop_clockevent = { | |
440 | .name = "xen", | |
441 | .features = CLOCK_EVT_FEAT_ONESHOT, | |
442 | ||
443 | .max_delta_ns = 0xffffffff, | |
444 | .min_delta_ns = TIMER_SLOP, | |
445 | ||
446 | .mult = 1, | |
447 | .shift = 0, | |
448 | .rating = 500, | |
449 | ||
450 | .set_mode = xen_timerop_set_mode, | |
451 | .set_next_event = xen_timerop_set_next_event, | |
452 | }; | |
453 | ||
454 | ||
455 | ||
456 | static void xen_vcpuop_set_mode(enum clock_event_mode mode, | |
457 | struct clock_event_device *evt) | |
458 | { | |
459 | int cpu = smp_processor_id(); | |
460 | ||
461 | switch (mode) { | |
462 | case CLOCK_EVT_MODE_PERIODIC: | |
463 | WARN_ON(1); /* unsupported */ | |
464 | break; | |
465 | ||
466 | case CLOCK_EVT_MODE_ONESHOT: | |
467 | if (HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL)) | |
468 | BUG(); | |
469 | break; | |
470 | ||
471 | case CLOCK_EVT_MODE_UNUSED: | |
472 | case CLOCK_EVT_MODE_SHUTDOWN: | |
473 | if (HYPERVISOR_vcpu_op(VCPUOP_stop_singleshot_timer, cpu, NULL) || | |
474 | HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL)) | |
475 | BUG(); | |
476 | break; | |
477 | } | |
478 | } | |
479 | ||
480 | static int xen_vcpuop_set_next_event(unsigned long delta, | |
481 | struct clock_event_device *evt) | |
482 | { | |
483 | int cpu = smp_processor_id(); | |
484 | struct vcpu_set_singleshot_timer single; | |
485 | int ret; | |
486 | ||
487 | WARN_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT); | |
488 | ||
489 | single.timeout_abs_ns = get_abs_timeout(delta); | |
490 | single.flags = VCPU_SSHOTTMR_future; | |
491 | ||
492 | ret = HYPERVISOR_vcpu_op(VCPUOP_set_singleshot_timer, cpu, &single); | |
493 | ||
494 | BUG_ON(ret != 0 && ret != -ETIME); | |
495 | ||
496 | return ret; | |
497 | } | |
498 | ||
499 | static const struct clock_event_device xen_vcpuop_clockevent = { | |
500 | .name = "xen", | |
501 | .features = CLOCK_EVT_FEAT_ONESHOT, | |
502 | ||
503 | .max_delta_ns = 0xffffffff, | |
504 | .min_delta_ns = TIMER_SLOP, | |
505 | ||
506 | .mult = 1, | |
507 | .shift = 0, | |
508 | .rating = 500, | |
509 | ||
510 | .set_mode = xen_vcpuop_set_mode, | |
511 | .set_next_event = xen_vcpuop_set_next_event, | |
512 | }; | |
513 | ||
514 | static const struct clock_event_device *xen_clockevent = | |
515 | &xen_timerop_clockevent; | |
516 | static DEFINE_PER_CPU(struct clock_event_device, xen_clock_events); | |
517 | ||
518 | static irqreturn_t xen_timer_interrupt(int irq, void *dev_id) | |
519 | { | |
520 | struct clock_event_device *evt = &__get_cpu_var(xen_clock_events); | |
521 | irqreturn_t ret; | |
522 | ||
523 | ret = IRQ_NONE; | |
524 | if (evt->event_handler) { | |
525 | evt->event_handler(evt); | |
526 | ret = IRQ_HANDLED; | |
527 | } | |
528 | ||
f91a8b44 JF |
529 | do_stolen_accounting(); |
530 | ||
15c84731 JF |
531 | return ret; |
532 | } | |
533 | ||
f87e4cac | 534 | void xen_setup_timer(int cpu) |
15c84731 JF |
535 | { |
536 | const char *name; | |
537 | struct clock_event_device *evt; | |
538 | int irq; | |
539 | ||
540 | printk(KERN_INFO "installing Xen timer for CPU %d\n", cpu); | |
541 | ||
542 | name = kasprintf(GFP_KERNEL, "timer%d", cpu); | |
543 | if (!name) | |
544 | name = "<timer kasprintf failed>"; | |
545 | ||
546 | irq = bind_virq_to_irqhandler(VIRQ_TIMER, cpu, xen_timer_interrupt, | |
547 | IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING, | |
548 | name, NULL); | |
549 | ||
f87e4cac | 550 | evt = &per_cpu(xen_clock_events, cpu); |
15c84731 JF |
551 | memcpy(evt, xen_clockevent, sizeof(*evt)); |
552 | ||
553 | evt->cpumask = cpumask_of_cpu(cpu); | |
554 | evt->irq = irq; | |
15c84731 | 555 | |
f91a8b44 | 556 | setup_runstate_info(cpu); |
f87e4cac JF |
557 | } |
558 | ||
559 | void xen_setup_cpu_clockevents(void) | |
560 | { | |
561 | BUG_ON(preemptible()); | |
f91a8b44 | 562 | |
f87e4cac | 563 | clockevents_register_device(&__get_cpu_var(xen_clock_events)); |
15c84731 JF |
564 | } |
565 | ||
566 | __init void xen_time_init(void) | |
567 | { | |
568 | int cpu = smp_processor_id(); | |
569 | ||
570 | get_time_values_from_xen(); | |
571 | ||
572 | clocksource_register(&xen_clocksource); | |
573 | ||
574 | if (HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL) == 0) { | |
f91a8b44 | 575 | /* Successfully turned off 100Hz tick, so we have the |
15c84731 JF |
576 | vcpuop-based timer interface */ |
577 | printk(KERN_DEBUG "Xen: using vcpuop timer interface\n"); | |
578 | xen_clockevent = &xen_vcpuop_clockevent; | |
579 | } | |
580 | ||
581 | /* Set initial system time with full resolution */ | |
582 | xen_read_wallclock(&xtime); | |
583 | set_normalized_timespec(&wall_to_monotonic, | |
584 | -xtime.tv_sec, -xtime.tv_nsec); | |
585 | ||
586 | tsc_disable = 0; | |
587 | ||
588 | xen_setup_timer(cpu); | |
f87e4cac | 589 | xen_setup_cpu_clockevents(); |
15c84731 | 590 | } |