Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 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> |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 14 | #include <linux/kernel_stat.h> |
Jeremy Fitzhardinge | f595ec9 | 2008-06-12 10:47:56 +0200 | [diff] [blame] | 15 | #include <linux/math64.h> |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 16 | |
Gerd Hoffmann | 1c7b67f | 2008-06-03 16:17:30 +0200 | [diff] [blame^] | 17 | #include <asm/pvclock.h> |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 18 | #include <asm/xen/hypervisor.h> |
| 19 | #include <asm/xen/hypercall.h> |
| 20 | |
| 21 | #include <xen/events.h> |
| 22 | #include <xen/interface/xen.h> |
| 23 | #include <xen/interface/vcpu.h> |
| 24 | |
| 25 | #include "xen-ops.h" |
| 26 | |
| 27 | #define XEN_SHIFT 22 |
| 28 | |
| 29 | /* Xen may fire a timer up to this many ns early */ |
| 30 | #define TIMER_SLOP 100000 |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 31 | #define NS_PER_TICK (1000000000LL / HZ) |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 32 | |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 33 | static cycle_t xen_clocksource_read(void); |
| 34 | |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 35 | /* runstate info updated by Xen */ |
| 36 | static DEFINE_PER_CPU(struct vcpu_runstate_info, runstate); |
| 37 | |
| 38 | /* snapshots of runstate info */ |
| 39 | static DEFINE_PER_CPU(struct vcpu_runstate_info, runstate_snapshot); |
| 40 | |
| 41 | /* unused ns of stolen and blocked time */ |
| 42 | static DEFINE_PER_CPU(u64, residual_stolen); |
| 43 | static DEFINE_PER_CPU(u64, residual_blocked); |
| 44 | |
| 45 | /* return an consistent snapshot of 64-bit time/counter value */ |
| 46 | static u64 get64(const u64 *p) |
| 47 | { |
| 48 | u64 ret; |
| 49 | |
| 50 | if (BITS_PER_LONG < 64) { |
| 51 | u32 *p32 = (u32 *)p; |
| 52 | u32 h, l; |
| 53 | |
| 54 | /* |
| 55 | * Read high then low, and then make sure high is |
| 56 | * still the same; this will only loop if low wraps |
| 57 | * and carries into high. |
| 58 | * XXX some clean way to make this endian-proof? |
| 59 | */ |
| 60 | do { |
| 61 | h = p32[1]; |
| 62 | barrier(); |
| 63 | l = p32[0]; |
| 64 | barrier(); |
| 65 | } while (p32[1] != h); |
| 66 | |
| 67 | ret = (((u64)h) << 32) | l; |
| 68 | } else |
| 69 | ret = *p; |
| 70 | |
| 71 | return ret; |
| 72 | } |
| 73 | |
| 74 | /* |
| 75 | * Runstate accounting |
| 76 | */ |
| 77 | static void get_runstate_snapshot(struct vcpu_runstate_info *res) |
| 78 | { |
| 79 | u64 state_time; |
| 80 | struct vcpu_runstate_info *state; |
| 81 | |
Jeremy Fitzhardinge | f120f13 | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 82 | BUG_ON(preemptible()); |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 83 | |
| 84 | state = &__get_cpu_var(runstate); |
| 85 | |
| 86 | /* |
| 87 | * The runstate info is always updated by the hypervisor on |
| 88 | * the current CPU, so there's no need to use anything |
| 89 | * stronger than a compiler barrier when fetching it. |
| 90 | */ |
| 91 | do { |
| 92 | state_time = get64(&state->state_entry_time); |
| 93 | barrier(); |
| 94 | *res = *state; |
| 95 | barrier(); |
| 96 | } while (get64(&state->state_entry_time) != state_time); |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 97 | } |
| 98 | |
Jeremy Fitzhardinge | f0d7339 | 2007-10-16 11:51:30 -0700 | [diff] [blame] | 99 | /* return true when a vcpu could run but has no real cpu to run on */ |
| 100 | bool xen_vcpu_stolen(int vcpu) |
| 101 | { |
| 102 | return per_cpu(runstate, vcpu).state == RUNSTATE_runnable; |
| 103 | } |
| 104 | |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 105 | static void setup_runstate_info(int cpu) |
| 106 | { |
| 107 | struct vcpu_register_runstate_memory_area area; |
| 108 | |
| 109 | area.addr.v = &per_cpu(runstate, cpu); |
| 110 | |
| 111 | if (HYPERVISOR_vcpu_op(VCPUOP_register_runstate_memory_area, |
| 112 | cpu, &area)) |
| 113 | BUG(); |
| 114 | } |
| 115 | |
| 116 | static void do_stolen_accounting(void) |
| 117 | { |
| 118 | struct vcpu_runstate_info state; |
| 119 | struct vcpu_runstate_info *snap; |
| 120 | s64 blocked, runnable, offline, stolen; |
| 121 | cputime_t ticks; |
| 122 | |
| 123 | get_runstate_snapshot(&state); |
| 124 | |
| 125 | WARN_ON(state.state != RUNSTATE_running); |
| 126 | |
| 127 | snap = &__get_cpu_var(runstate_snapshot); |
| 128 | |
| 129 | /* work out how much time the VCPU has not been runn*ing* */ |
| 130 | blocked = state.time[RUNSTATE_blocked] - snap->time[RUNSTATE_blocked]; |
| 131 | runnable = state.time[RUNSTATE_runnable] - snap->time[RUNSTATE_runnable]; |
| 132 | offline = state.time[RUNSTATE_offline] - snap->time[RUNSTATE_offline]; |
| 133 | |
| 134 | *snap = state; |
| 135 | |
| 136 | /* Add the appropriate number of ticks of stolen time, |
| 137 | including any left-overs from last time. Passing NULL to |
| 138 | account_steal_time accounts the time as stolen. */ |
| 139 | stolen = runnable + offline + __get_cpu_var(residual_stolen); |
| 140 | |
| 141 | if (stolen < 0) |
| 142 | stolen = 0; |
| 143 | |
Jeremy Fitzhardinge | f595ec9 | 2008-06-12 10:47:56 +0200 | [diff] [blame] | 144 | ticks = iter_div_u64_rem(stolen, NS_PER_TICK, &stolen); |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 145 | __get_cpu_var(residual_stolen) = stolen; |
| 146 | account_steal_time(NULL, ticks); |
| 147 | |
| 148 | /* Add the appropriate number of ticks of blocked time, |
| 149 | including any left-overs from last time. Passing idle to |
| 150 | account_steal_time accounts the time as idle/wait. */ |
| 151 | blocked += __get_cpu_var(residual_blocked); |
| 152 | |
| 153 | if (blocked < 0) |
| 154 | blocked = 0; |
| 155 | |
Jeremy Fitzhardinge | f595ec9 | 2008-06-12 10:47:56 +0200 | [diff] [blame] | 156 | ticks = iter_div_u64_rem(blocked, NS_PER_TICK, &blocked); |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 157 | __get_cpu_var(residual_blocked) = blocked; |
| 158 | account_steal_time(idle_task(smp_processor_id()), ticks); |
| 159 | } |
| 160 | |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 161 | /* |
| 162 | * Xen sched_clock implementation. Returns the number of unstolen |
| 163 | * nanoseconds, which is nanoseconds the VCPU spent in RUNNING+BLOCKED |
| 164 | * states. |
| 165 | */ |
| 166 | unsigned long long xen_sched_clock(void) |
| 167 | { |
| 168 | struct vcpu_runstate_info state; |
Jeremy Fitzhardinge | f120f13 | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 169 | cycle_t now; |
| 170 | u64 ret; |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 171 | s64 offset; |
| 172 | |
Jeremy Fitzhardinge | f120f13 | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 173 | /* |
| 174 | * Ideally sched_clock should be called on a per-cpu basis |
| 175 | * anyway, so preempt should already be disabled, but that's |
| 176 | * not current practice at the moment. |
| 177 | */ |
| 178 | preempt_disable(); |
| 179 | |
| 180 | now = xen_clocksource_read(); |
| 181 | |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 182 | get_runstate_snapshot(&state); |
| 183 | |
| 184 | WARN_ON(state.state != RUNSTATE_running); |
| 185 | |
| 186 | offset = now - state.state_entry_time; |
| 187 | if (offset < 0) |
| 188 | offset = 0; |
| 189 | |
Jeremy Fitzhardinge | f120f13 | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 190 | ret = state.time[RUNSTATE_blocked] + |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 191 | state.time[RUNSTATE_running] + |
| 192 | offset; |
Jeremy Fitzhardinge | f120f13 | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 193 | |
| 194 | preempt_enable(); |
| 195 | |
| 196 | return ret; |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 197 | } |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 198 | |
| 199 | |
| 200 | /* Get the CPU speed from Xen */ |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 201 | unsigned long xen_cpu_khz(void) |
| 202 | { |
Harvey Harrison | 88a5ac8 | 2008-02-09 23:24:08 +0100 | [diff] [blame] | 203 | u64 xen_khz = 1000000ULL << 32; |
Gerd Hoffmann | 1c7b67f | 2008-06-03 16:17:30 +0200 | [diff] [blame^] | 204 | const struct pvclock_vcpu_time_info *info = |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 205 | &HYPERVISOR_shared_info->vcpu_info[0].time; |
| 206 | |
Harvey Harrison | 88a5ac8 | 2008-02-09 23:24:08 +0100 | [diff] [blame] | 207 | do_div(xen_khz, info->tsc_to_system_mul); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 208 | if (info->tsc_shift < 0) |
Harvey Harrison | 88a5ac8 | 2008-02-09 23:24:08 +0100 | [diff] [blame] | 209 | xen_khz <<= -info->tsc_shift; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 210 | else |
Harvey Harrison | 88a5ac8 | 2008-02-09 23:24:08 +0100 | [diff] [blame] | 211 | xen_khz >>= info->tsc_shift; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 212 | |
Harvey Harrison | 88a5ac8 | 2008-02-09 23:24:08 +0100 | [diff] [blame] | 213 | return xen_khz; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 214 | } |
| 215 | |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 216 | static cycle_t xen_clocksource_read(void) |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 217 | { |
Gerd Hoffmann | 1c7b67f | 2008-06-03 16:17:30 +0200 | [diff] [blame^] | 218 | struct pvclock_vcpu_time_info *src; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 219 | cycle_t ret; |
| 220 | |
Gerd Hoffmann | 1c7b67f | 2008-06-03 16:17:30 +0200 | [diff] [blame^] | 221 | src = &get_cpu_var(xen_vcpu)->time; |
| 222 | ret = pvclock_clocksource_read(src); |
| 223 | put_cpu_var(xen_vcpu); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 224 | return ret; |
| 225 | } |
| 226 | |
| 227 | static void xen_read_wallclock(struct timespec *ts) |
| 228 | { |
Gerd Hoffmann | 1c7b67f | 2008-06-03 16:17:30 +0200 | [diff] [blame^] | 229 | struct shared_info *s = HYPERVISOR_shared_info; |
| 230 | struct pvclock_wall_clock *wall_clock = &(s->wc); |
| 231 | struct pvclock_vcpu_time_info *vcpu_time; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 232 | |
Gerd Hoffmann | 1c7b67f | 2008-06-03 16:17:30 +0200 | [diff] [blame^] | 233 | vcpu_time = &get_cpu_var(xen_vcpu)->time; |
| 234 | pvclock_read_wallclock(wall_clock, vcpu_time, ts); |
| 235 | put_cpu_var(xen_vcpu); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 236 | } |
| 237 | |
| 238 | unsigned long xen_get_wallclock(void) |
| 239 | { |
| 240 | struct timespec ts; |
| 241 | |
| 242 | xen_read_wallclock(&ts); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 243 | return ts.tv_sec; |
| 244 | } |
| 245 | |
| 246 | int xen_set_wallclock(unsigned long now) |
| 247 | { |
| 248 | /* do nothing for domU */ |
| 249 | return -1; |
| 250 | } |
| 251 | |
| 252 | static struct clocksource xen_clocksource __read_mostly = { |
| 253 | .name = "xen", |
| 254 | .rating = 400, |
| 255 | .read = xen_clocksource_read, |
| 256 | .mask = ~0, |
| 257 | .mult = 1<<XEN_SHIFT, /* time directly in nanoseconds */ |
| 258 | .shift = XEN_SHIFT, |
| 259 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
| 260 | }; |
| 261 | |
| 262 | /* |
| 263 | Xen clockevent implementation |
| 264 | |
| 265 | Xen has two clockevent implementations: |
| 266 | |
| 267 | The old timer_op one works with all released versions of Xen prior |
| 268 | to version 3.0.4. This version of the hypervisor provides a |
| 269 | single-shot timer with nanosecond resolution. However, sharing the |
| 270 | same event channel is a 100Hz tick which is delivered while the |
| 271 | vcpu is running. We don't care about or use this tick, but it will |
| 272 | cause the core time code to think the timer fired too soon, and |
| 273 | will end up resetting it each time. It could be filtered, but |
| 274 | doing so has complications when the ktime clocksource is not yet |
| 275 | the xen clocksource (ie, at boot time). |
| 276 | |
| 277 | The new vcpu_op-based timer interface allows the tick timer period |
| 278 | to be changed or turned off. The tick timer is not useful as a |
| 279 | periodic timer because events are only delivered to running vcpus. |
| 280 | The one-shot timer can report when a timeout is in the past, so |
| 281 | set_next_event is capable of returning -ETIME when appropriate. |
| 282 | This interface is used when available. |
| 283 | */ |
| 284 | |
| 285 | |
| 286 | /* |
| 287 | Get a hypervisor absolute time. In theory we could maintain an |
| 288 | offset between the kernel's time and the hypervisor's time, and |
| 289 | apply that to a kernel's absolute timeout. Unfortunately the |
| 290 | hypervisor and kernel times can drift even if the kernel is using |
| 291 | the Xen clocksource, because ntp can warp the kernel's clocksource. |
| 292 | */ |
| 293 | static s64 get_abs_timeout(unsigned long delta) |
| 294 | { |
| 295 | return xen_clocksource_read() + delta; |
| 296 | } |
| 297 | |
| 298 | static void xen_timerop_set_mode(enum clock_event_mode mode, |
| 299 | struct clock_event_device *evt) |
| 300 | { |
| 301 | switch (mode) { |
| 302 | case CLOCK_EVT_MODE_PERIODIC: |
| 303 | /* unsupported */ |
| 304 | WARN_ON(1); |
| 305 | break; |
| 306 | |
| 307 | case CLOCK_EVT_MODE_ONESHOT: |
Thomas Gleixner | 18de5bc | 2007-07-21 04:37:34 -0700 | [diff] [blame] | 308 | case CLOCK_EVT_MODE_RESUME: |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 309 | break; |
| 310 | |
| 311 | case CLOCK_EVT_MODE_UNUSED: |
| 312 | case CLOCK_EVT_MODE_SHUTDOWN: |
| 313 | HYPERVISOR_set_timer_op(0); /* cancel timeout */ |
| 314 | break; |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | static int xen_timerop_set_next_event(unsigned long delta, |
| 319 | struct clock_event_device *evt) |
| 320 | { |
| 321 | WARN_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT); |
| 322 | |
| 323 | if (HYPERVISOR_set_timer_op(get_abs_timeout(delta)) < 0) |
| 324 | BUG(); |
| 325 | |
| 326 | /* We may have missed the deadline, but there's no real way of |
| 327 | knowing for sure. If the event was in the past, then we'll |
| 328 | get an immediate interrupt. */ |
| 329 | |
| 330 | return 0; |
| 331 | } |
| 332 | |
| 333 | static const struct clock_event_device xen_timerop_clockevent = { |
| 334 | .name = "xen", |
| 335 | .features = CLOCK_EVT_FEAT_ONESHOT, |
| 336 | |
| 337 | .max_delta_ns = 0xffffffff, |
| 338 | .min_delta_ns = TIMER_SLOP, |
| 339 | |
| 340 | .mult = 1, |
| 341 | .shift = 0, |
| 342 | .rating = 500, |
| 343 | |
| 344 | .set_mode = xen_timerop_set_mode, |
| 345 | .set_next_event = xen_timerop_set_next_event, |
| 346 | }; |
| 347 | |
| 348 | |
| 349 | |
| 350 | static void xen_vcpuop_set_mode(enum clock_event_mode mode, |
| 351 | struct clock_event_device *evt) |
| 352 | { |
| 353 | int cpu = smp_processor_id(); |
| 354 | |
| 355 | switch (mode) { |
| 356 | case CLOCK_EVT_MODE_PERIODIC: |
| 357 | WARN_ON(1); /* unsupported */ |
| 358 | break; |
| 359 | |
| 360 | case CLOCK_EVT_MODE_ONESHOT: |
| 361 | if (HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL)) |
| 362 | BUG(); |
| 363 | break; |
| 364 | |
| 365 | case CLOCK_EVT_MODE_UNUSED: |
| 366 | case CLOCK_EVT_MODE_SHUTDOWN: |
| 367 | if (HYPERVISOR_vcpu_op(VCPUOP_stop_singleshot_timer, cpu, NULL) || |
| 368 | HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL)) |
| 369 | BUG(); |
| 370 | break; |
Thomas Gleixner | 18de5bc | 2007-07-21 04:37:34 -0700 | [diff] [blame] | 371 | case CLOCK_EVT_MODE_RESUME: |
| 372 | break; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 373 | } |
| 374 | } |
| 375 | |
| 376 | static int xen_vcpuop_set_next_event(unsigned long delta, |
| 377 | struct clock_event_device *evt) |
| 378 | { |
| 379 | int cpu = smp_processor_id(); |
| 380 | struct vcpu_set_singleshot_timer single; |
| 381 | int ret; |
| 382 | |
| 383 | WARN_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT); |
| 384 | |
| 385 | single.timeout_abs_ns = get_abs_timeout(delta); |
| 386 | single.flags = VCPU_SSHOTTMR_future; |
| 387 | |
| 388 | ret = HYPERVISOR_vcpu_op(VCPUOP_set_singleshot_timer, cpu, &single); |
| 389 | |
| 390 | BUG_ON(ret != 0 && ret != -ETIME); |
| 391 | |
| 392 | return ret; |
| 393 | } |
| 394 | |
| 395 | static const struct clock_event_device xen_vcpuop_clockevent = { |
| 396 | .name = "xen", |
| 397 | .features = CLOCK_EVT_FEAT_ONESHOT, |
| 398 | |
| 399 | .max_delta_ns = 0xffffffff, |
| 400 | .min_delta_ns = TIMER_SLOP, |
| 401 | |
| 402 | .mult = 1, |
| 403 | .shift = 0, |
| 404 | .rating = 500, |
| 405 | |
| 406 | .set_mode = xen_vcpuop_set_mode, |
| 407 | .set_next_event = xen_vcpuop_set_next_event, |
| 408 | }; |
| 409 | |
| 410 | static const struct clock_event_device *xen_clockevent = |
| 411 | &xen_timerop_clockevent; |
| 412 | static DEFINE_PER_CPU(struct clock_event_device, xen_clock_events); |
| 413 | |
| 414 | static irqreturn_t xen_timer_interrupt(int irq, void *dev_id) |
| 415 | { |
| 416 | struct clock_event_device *evt = &__get_cpu_var(xen_clock_events); |
| 417 | irqreturn_t ret; |
| 418 | |
| 419 | ret = IRQ_NONE; |
| 420 | if (evt->event_handler) { |
| 421 | evt->event_handler(evt); |
| 422 | ret = IRQ_HANDLED; |
| 423 | } |
| 424 | |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 425 | do_stolen_accounting(); |
| 426 | |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 427 | return ret; |
| 428 | } |
| 429 | |
Jeremy Fitzhardinge | f87e4ca | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 430 | void xen_setup_timer(int cpu) |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 431 | { |
| 432 | const char *name; |
| 433 | struct clock_event_device *evt; |
| 434 | int irq; |
| 435 | |
| 436 | printk(KERN_INFO "installing Xen timer for CPU %d\n", cpu); |
| 437 | |
| 438 | name = kasprintf(GFP_KERNEL, "timer%d", cpu); |
| 439 | if (!name) |
| 440 | name = "<timer kasprintf failed>"; |
| 441 | |
| 442 | irq = bind_virq_to_irqhandler(VIRQ_TIMER, cpu, xen_timer_interrupt, |
| 443 | IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING, |
| 444 | name, NULL); |
| 445 | |
Jeremy Fitzhardinge | f87e4ca | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 446 | evt = &per_cpu(xen_clock_events, cpu); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 447 | memcpy(evt, xen_clockevent, sizeof(*evt)); |
| 448 | |
| 449 | evt->cpumask = cpumask_of_cpu(cpu); |
| 450 | evt->irq = irq; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 451 | |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 452 | setup_runstate_info(cpu); |
Jeremy Fitzhardinge | f87e4ca | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 453 | } |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 454 | |
Jeremy Fitzhardinge | f87e4ca | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 455 | void xen_setup_cpu_clockevents(void) |
| 456 | { |
| 457 | BUG_ON(preemptible()); |
| 458 | |
| 459 | clockevents_register_device(&__get_cpu_var(xen_clock_events)); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 460 | } |
| 461 | |
| 462 | __init void xen_time_init(void) |
| 463 | { |
| 464 | int cpu = smp_processor_id(); |
| 465 | |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 466 | clocksource_register(&xen_clocksource); |
| 467 | |
| 468 | if (HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL) == 0) { |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 469 | /* Successfully turned off 100Hz tick, so we have the |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 470 | vcpuop-based timer interface */ |
| 471 | printk(KERN_DEBUG "Xen: using vcpuop timer interface\n"); |
| 472 | xen_clockevent = &xen_vcpuop_clockevent; |
| 473 | } |
| 474 | |
| 475 | /* Set initial system time with full resolution */ |
| 476 | xen_read_wallclock(&xtime); |
| 477 | set_normalized_timespec(&wall_to_monotonic, |
| 478 | -xtime.tv_sec, -xtime.tv_nsec); |
| 479 | |
Andi Kleen | 404ee5b | 2008-01-30 13:33:20 +0100 | [diff] [blame] | 480 | setup_force_cpu_cap(X86_FEATURE_TSC); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 481 | |
| 482 | xen_setup_timer(cpu); |
Jeremy Fitzhardinge | f87e4ca | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 483 | xen_setup_cpu_clockevents(); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 484 | } |