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 | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 33 | /* runstate info updated by Xen */ |
| 34 | static DEFINE_PER_CPU(struct vcpu_runstate_info, runstate); |
| 35 | |
| 36 | /* snapshots of runstate info */ |
| 37 | static DEFINE_PER_CPU(struct vcpu_runstate_info, runstate_snapshot); |
| 38 | |
| 39 | /* unused ns of stolen and blocked time */ |
| 40 | static DEFINE_PER_CPU(u64, residual_stolen); |
| 41 | static DEFINE_PER_CPU(u64, residual_blocked); |
| 42 | |
| 43 | /* return an consistent snapshot of 64-bit time/counter value */ |
| 44 | static u64 get64(const u64 *p) |
| 45 | { |
| 46 | u64 ret; |
| 47 | |
| 48 | if (BITS_PER_LONG < 64) { |
| 49 | u32 *p32 = (u32 *)p; |
| 50 | u32 h, l; |
| 51 | |
| 52 | /* |
| 53 | * Read high then low, and then make sure high is |
| 54 | * still the same; this will only loop if low wraps |
| 55 | * and carries into high. |
| 56 | * XXX some clean way to make this endian-proof? |
| 57 | */ |
| 58 | do { |
| 59 | h = p32[1]; |
| 60 | barrier(); |
| 61 | l = p32[0]; |
| 62 | barrier(); |
| 63 | } while (p32[1] != h); |
| 64 | |
| 65 | ret = (((u64)h) << 32) | l; |
| 66 | } else |
| 67 | ret = *p; |
| 68 | |
| 69 | return ret; |
| 70 | } |
| 71 | |
| 72 | /* |
| 73 | * Runstate accounting |
| 74 | */ |
| 75 | static void get_runstate_snapshot(struct vcpu_runstate_info *res) |
| 76 | { |
| 77 | u64 state_time; |
| 78 | struct vcpu_runstate_info *state; |
| 79 | |
Jeremy Fitzhardinge | f120f13 | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 80 | BUG_ON(preemptible()); |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 81 | |
| 82 | state = &__get_cpu_var(runstate); |
| 83 | |
| 84 | /* |
| 85 | * The runstate info is always updated by the hypervisor on |
| 86 | * the current CPU, so there's no need to use anything |
| 87 | * stronger than a compiler barrier when fetching it. |
| 88 | */ |
| 89 | do { |
| 90 | state_time = get64(&state->state_entry_time); |
| 91 | barrier(); |
| 92 | *res = *state; |
| 93 | barrier(); |
| 94 | } while (get64(&state->state_entry_time) != state_time); |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 95 | } |
| 96 | |
Jeremy Fitzhardinge | f0d7339 | 2007-10-16 11:51:30 -0700 | [diff] [blame] | 97 | /* return true when a vcpu could run but has no real cpu to run on */ |
| 98 | bool xen_vcpu_stolen(int vcpu) |
| 99 | { |
| 100 | return per_cpu(runstate, vcpu).state == RUNSTATE_runnable; |
| 101 | } |
| 102 | |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 103 | static void setup_runstate_info(int cpu) |
| 104 | { |
| 105 | struct vcpu_register_runstate_memory_area area; |
| 106 | |
| 107 | area.addr.v = &per_cpu(runstate, cpu); |
| 108 | |
| 109 | if (HYPERVISOR_vcpu_op(VCPUOP_register_runstate_memory_area, |
| 110 | cpu, &area)) |
| 111 | BUG(); |
| 112 | } |
| 113 | |
| 114 | static void do_stolen_accounting(void) |
| 115 | { |
| 116 | struct vcpu_runstate_info state; |
| 117 | struct vcpu_runstate_info *snap; |
| 118 | s64 blocked, runnable, offline, stolen; |
| 119 | cputime_t ticks; |
| 120 | |
| 121 | get_runstate_snapshot(&state); |
| 122 | |
| 123 | WARN_ON(state.state != RUNSTATE_running); |
| 124 | |
| 125 | snap = &__get_cpu_var(runstate_snapshot); |
| 126 | |
| 127 | /* work out how much time the VCPU has not been runn*ing* */ |
| 128 | blocked = state.time[RUNSTATE_blocked] - snap->time[RUNSTATE_blocked]; |
| 129 | runnable = state.time[RUNSTATE_runnable] - snap->time[RUNSTATE_runnable]; |
| 130 | offline = state.time[RUNSTATE_offline] - snap->time[RUNSTATE_offline]; |
| 131 | |
| 132 | *snap = state; |
| 133 | |
| 134 | /* Add the appropriate number of ticks of stolen time, |
Martin Schwidefsky | 79741dd | 2008-12-31 15:11:38 +0100 | [diff] [blame] | 135 | including any left-overs from last time. */ |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 136 | stolen = runnable + offline + __get_cpu_var(residual_stolen); |
| 137 | |
| 138 | if (stolen < 0) |
| 139 | stolen = 0; |
| 140 | |
Jeremy Fitzhardinge | f595ec9 | 2008-06-12 10:47:56 +0200 | [diff] [blame] | 141 | ticks = iter_div_u64_rem(stolen, NS_PER_TICK, &stolen); |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 142 | __get_cpu_var(residual_stolen) = stolen; |
Martin Schwidefsky | 79741dd | 2008-12-31 15:11:38 +0100 | [diff] [blame] | 143 | account_steal_ticks(ticks); |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 144 | |
| 145 | /* Add the appropriate number of ticks of blocked time, |
Martin Schwidefsky | 79741dd | 2008-12-31 15:11:38 +0100 | [diff] [blame] | 146 | including any left-overs from last time. */ |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 147 | blocked += __get_cpu_var(residual_blocked); |
| 148 | |
| 149 | if (blocked < 0) |
| 150 | blocked = 0; |
| 151 | |
Jeremy Fitzhardinge | f595ec9 | 2008-06-12 10:47:56 +0200 | [diff] [blame] | 152 | ticks = iter_div_u64_rem(blocked, NS_PER_TICK, &blocked); |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 153 | __get_cpu_var(residual_blocked) = blocked; |
Martin Schwidefsky | 79741dd | 2008-12-31 15:11:38 +0100 | [diff] [blame] | 154 | account_idle_ticks(ticks); |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 155 | } |
| 156 | |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 157 | /* |
| 158 | * Xen sched_clock implementation. Returns the number of unstolen |
| 159 | * nanoseconds, which is nanoseconds the VCPU spent in RUNNING+BLOCKED |
| 160 | * states. |
| 161 | */ |
| 162 | unsigned long long xen_sched_clock(void) |
| 163 | { |
| 164 | struct vcpu_runstate_info state; |
Jeremy Fitzhardinge | f120f13 | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 165 | cycle_t now; |
| 166 | u64 ret; |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 167 | s64 offset; |
| 168 | |
Jeremy Fitzhardinge | f120f13 | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 169 | /* |
| 170 | * Ideally sched_clock should be called on a per-cpu basis |
| 171 | * anyway, so preempt should already be disabled, but that's |
| 172 | * not current practice at the moment. |
| 173 | */ |
| 174 | preempt_disable(); |
| 175 | |
| 176 | now = xen_clocksource_read(); |
| 177 | |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 178 | get_runstate_snapshot(&state); |
| 179 | |
| 180 | WARN_ON(state.state != RUNSTATE_running); |
| 181 | |
| 182 | offset = now - state.state_entry_time; |
| 183 | if (offset < 0) |
| 184 | offset = 0; |
| 185 | |
Jeremy Fitzhardinge | f120f13 | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 186 | ret = state.time[RUNSTATE_blocked] + |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 187 | state.time[RUNSTATE_running] + |
| 188 | offset; |
Jeremy Fitzhardinge | f120f13 | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 189 | |
| 190 | preempt_enable(); |
| 191 | |
| 192 | return ret; |
Jeremy Fitzhardinge | ab55028 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 193 | } |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 194 | |
| 195 | |
Alok Kataria | e93ef94 | 2008-07-01 11:43:36 -0700 | [diff] [blame] | 196 | /* Get the TSC speed from Xen */ |
| 197 | unsigned long xen_tsc_khz(void) |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 198 | { |
Glauber Costa | 3807f34 | 2008-07-28 11:47:52 -0300 | [diff] [blame] | 199 | struct pvclock_vcpu_time_info *info = |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 200 | &HYPERVISOR_shared_info->vcpu_info[0].time; |
| 201 | |
Glauber Costa | 3807f34 | 2008-07-28 11:47:52 -0300 | [diff] [blame] | 202 | return pvclock_tsc_khz(info); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 203 | } |
| 204 | |
Jeremy Fitzhardinge | ee7686b | 2008-08-21 13:17:56 -0700 | [diff] [blame] | 205 | cycle_t xen_clocksource_read(void) |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 206 | { |
Gerd Hoffmann | 1c7b67f | 2008-06-03 16:17:30 +0200 | [diff] [blame] | 207 | struct pvclock_vcpu_time_info *src; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 208 | cycle_t ret; |
| 209 | |
Gerd Hoffmann | 1c7b67f | 2008-06-03 16:17:30 +0200 | [diff] [blame] | 210 | src = &get_cpu_var(xen_vcpu)->time; |
| 211 | ret = pvclock_clocksource_read(src); |
| 212 | put_cpu_var(xen_vcpu); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 213 | return ret; |
| 214 | } |
| 215 | |
Magnus Damm | 8e19608 | 2009-04-21 12:24:00 -0700 | [diff] [blame^] | 216 | static cycle_t xen_clocksource_get_cycles(struct clocksource *cs) |
| 217 | { |
| 218 | return xen_clocksource_read(); |
| 219 | } |
| 220 | |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 221 | static void xen_read_wallclock(struct timespec *ts) |
| 222 | { |
Gerd Hoffmann | 1c7b67f | 2008-06-03 16:17:30 +0200 | [diff] [blame] | 223 | struct shared_info *s = HYPERVISOR_shared_info; |
| 224 | struct pvclock_wall_clock *wall_clock = &(s->wc); |
| 225 | struct pvclock_vcpu_time_info *vcpu_time; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 226 | |
Gerd Hoffmann | 1c7b67f | 2008-06-03 16:17:30 +0200 | [diff] [blame] | 227 | vcpu_time = &get_cpu_var(xen_vcpu)->time; |
| 228 | pvclock_read_wallclock(wall_clock, vcpu_time, ts); |
| 229 | put_cpu_var(xen_vcpu); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 230 | } |
| 231 | |
| 232 | unsigned long xen_get_wallclock(void) |
| 233 | { |
| 234 | struct timespec ts; |
| 235 | |
| 236 | xen_read_wallclock(&ts); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 237 | return ts.tv_sec; |
| 238 | } |
| 239 | |
| 240 | int xen_set_wallclock(unsigned long now) |
| 241 | { |
| 242 | /* do nothing for domU */ |
| 243 | return -1; |
| 244 | } |
| 245 | |
| 246 | static struct clocksource xen_clocksource __read_mostly = { |
| 247 | .name = "xen", |
| 248 | .rating = 400, |
Magnus Damm | 8e19608 | 2009-04-21 12:24:00 -0700 | [diff] [blame^] | 249 | .read = xen_clocksource_get_cycles, |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 250 | .mask = ~0, |
| 251 | .mult = 1<<XEN_SHIFT, /* time directly in nanoseconds */ |
| 252 | .shift = XEN_SHIFT, |
| 253 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
| 254 | }; |
| 255 | |
| 256 | /* |
| 257 | Xen clockevent implementation |
| 258 | |
| 259 | Xen has two clockevent implementations: |
| 260 | |
| 261 | The old timer_op one works with all released versions of Xen prior |
| 262 | to version 3.0.4. This version of the hypervisor provides a |
| 263 | single-shot timer with nanosecond resolution. However, sharing the |
| 264 | same event channel is a 100Hz tick which is delivered while the |
| 265 | vcpu is running. We don't care about or use this tick, but it will |
| 266 | cause the core time code to think the timer fired too soon, and |
| 267 | will end up resetting it each time. It could be filtered, but |
| 268 | doing so has complications when the ktime clocksource is not yet |
| 269 | the xen clocksource (ie, at boot time). |
| 270 | |
| 271 | The new vcpu_op-based timer interface allows the tick timer period |
| 272 | to be changed or turned off. The tick timer is not useful as a |
| 273 | periodic timer because events are only delivered to running vcpus. |
| 274 | The one-shot timer can report when a timeout is in the past, so |
| 275 | set_next_event is capable of returning -ETIME when appropriate. |
| 276 | This interface is used when available. |
| 277 | */ |
| 278 | |
| 279 | |
| 280 | /* |
| 281 | Get a hypervisor absolute time. In theory we could maintain an |
| 282 | offset between the kernel's time and the hypervisor's time, and |
| 283 | apply that to a kernel's absolute timeout. Unfortunately the |
| 284 | hypervisor and kernel times can drift even if the kernel is using |
| 285 | the Xen clocksource, because ntp can warp the kernel's clocksource. |
| 286 | */ |
| 287 | static s64 get_abs_timeout(unsigned long delta) |
| 288 | { |
| 289 | return xen_clocksource_read() + delta; |
| 290 | } |
| 291 | |
| 292 | static void xen_timerop_set_mode(enum clock_event_mode mode, |
| 293 | struct clock_event_device *evt) |
| 294 | { |
| 295 | switch (mode) { |
| 296 | case CLOCK_EVT_MODE_PERIODIC: |
| 297 | /* unsupported */ |
| 298 | WARN_ON(1); |
| 299 | break; |
| 300 | |
| 301 | case CLOCK_EVT_MODE_ONESHOT: |
Thomas Gleixner | 18de5bc | 2007-07-21 04:37:34 -0700 | [diff] [blame] | 302 | case CLOCK_EVT_MODE_RESUME: |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 303 | break; |
| 304 | |
| 305 | case CLOCK_EVT_MODE_UNUSED: |
| 306 | case CLOCK_EVT_MODE_SHUTDOWN: |
| 307 | HYPERVISOR_set_timer_op(0); /* cancel timeout */ |
| 308 | break; |
| 309 | } |
| 310 | } |
| 311 | |
| 312 | static int xen_timerop_set_next_event(unsigned long delta, |
| 313 | struct clock_event_device *evt) |
| 314 | { |
| 315 | WARN_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT); |
| 316 | |
| 317 | if (HYPERVISOR_set_timer_op(get_abs_timeout(delta)) < 0) |
| 318 | BUG(); |
| 319 | |
| 320 | /* We may have missed the deadline, but there's no real way of |
| 321 | knowing for sure. If the event was in the past, then we'll |
| 322 | get an immediate interrupt. */ |
| 323 | |
| 324 | return 0; |
| 325 | } |
| 326 | |
| 327 | static const struct clock_event_device xen_timerop_clockevent = { |
| 328 | .name = "xen", |
| 329 | .features = CLOCK_EVT_FEAT_ONESHOT, |
| 330 | |
| 331 | .max_delta_ns = 0xffffffff, |
| 332 | .min_delta_ns = TIMER_SLOP, |
| 333 | |
| 334 | .mult = 1, |
| 335 | .shift = 0, |
| 336 | .rating = 500, |
| 337 | |
| 338 | .set_mode = xen_timerop_set_mode, |
| 339 | .set_next_event = xen_timerop_set_next_event, |
| 340 | }; |
| 341 | |
| 342 | |
| 343 | |
| 344 | static void xen_vcpuop_set_mode(enum clock_event_mode mode, |
| 345 | struct clock_event_device *evt) |
| 346 | { |
| 347 | int cpu = smp_processor_id(); |
| 348 | |
| 349 | switch (mode) { |
| 350 | case CLOCK_EVT_MODE_PERIODIC: |
| 351 | WARN_ON(1); /* unsupported */ |
| 352 | break; |
| 353 | |
| 354 | case CLOCK_EVT_MODE_ONESHOT: |
| 355 | if (HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL)) |
| 356 | BUG(); |
| 357 | break; |
| 358 | |
| 359 | case CLOCK_EVT_MODE_UNUSED: |
| 360 | case CLOCK_EVT_MODE_SHUTDOWN: |
| 361 | if (HYPERVISOR_vcpu_op(VCPUOP_stop_singleshot_timer, cpu, NULL) || |
| 362 | HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL)) |
| 363 | BUG(); |
| 364 | break; |
Thomas Gleixner | 18de5bc | 2007-07-21 04:37:34 -0700 | [diff] [blame] | 365 | case CLOCK_EVT_MODE_RESUME: |
| 366 | break; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 367 | } |
| 368 | } |
| 369 | |
| 370 | static int xen_vcpuop_set_next_event(unsigned long delta, |
| 371 | struct clock_event_device *evt) |
| 372 | { |
| 373 | int cpu = smp_processor_id(); |
| 374 | struct vcpu_set_singleshot_timer single; |
| 375 | int ret; |
| 376 | |
| 377 | WARN_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT); |
| 378 | |
| 379 | single.timeout_abs_ns = get_abs_timeout(delta); |
| 380 | single.flags = VCPU_SSHOTTMR_future; |
| 381 | |
| 382 | ret = HYPERVISOR_vcpu_op(VCPUOP_set_singleshot_timer, cpu, &single); |
| 383 | |
| 384 | BUG_ON(ret != 0 && ret != -ETIME); |
| 385 | |
| 386 | return ret; |
| 387 | } |
| 388 | |
| 389 | static const struct clock_event_device xen_vcpuop_clockevent = { |
| 390 | .name = "xen", |
| 391 | .features = CLOCK_EVT_FEAT_ONESHOT, |
| 392 | |
| 393 | .max_delta_ns = 0xffffffff, |
| 394 | .min_delta_ns = TIMER_SLOP, |
| 395 | |
| 396 | .mult = 1, |
| 397 | .shift = 0, |
| 398 | .rating = 500, |
| 399 | |
| 400 | .set_mode = xen_vcpuop_set_mode, |
| 401 | .set_next_event = xen_vcpuop_set_next_event, |
| 402 | }; |
| 403 | |
| 404 | static const struct clock_event_device *xen_clockevent = |
| 405 | &xen_timerop_clockevent; |
| 406 | static DEFINE_PER_CPU(struct clock_event_device, xen_clock_events); |
| 407 | |
| 408 | static irqreturn_t xen_timer_interrupt(int irq, void *dev_id) |
| 409 | { |
| 410 | struct clock_event_device *evt = &__get_cpu_var(xen_clock_events); |
| 411 | irqreturn_t ret; |
| 412 | |
| 413 | ret = IRQ_NONE; |
| 414 | if (evt->event_handler) { |
| 415 | evt->event_handler(evt); |
| 416 | ret = IRQ_HANDLED; |
| 417 | } |
| 418 | |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 419 | do_stolen_accounting(); |
| 420 | |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 421 | return ret; |
| 422 | } |
| 423 | |
Jeremy Fitzhardinge | f87e4ca | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 424 | void xen_setup_timer(int cpu) |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 425 | { |
| 426 | const char *name; |
| 427 | struct clock_event_device *evt; |
| 428 | int irq; |
| 429 | |
| 430 | printk(KERN_INFO "installing Xen timer for CPU %d\n", cpu); |
| 431 | |
| 432 | name = kasprintf(GFP_KERNEL, "timer%d", cpu); |
| 433 | if (!name) |
| 434 | name = "<timer kasprintf failed>"; |
| 435 | |
| 436 | irq = bind_virq_to_irqhandler(VIRQ_TIMER, cpu, xen_timer_interrupt, |
| 437 | IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING, |
| 438 | name, NULL); |
| 439 | |
Jeremy Fitzhardinge | f87e4ca | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 440 | evt = &per_cpu(xen_clock_events, cpu); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 441 | memcpy(evt, xen_clockevent, sizeof(*evt)); |
| 442 | |
Rusty Russell | 320ab2b | 2008-12-13 21:20:26 +1030 | [diff] [blame] | 443 | evt->cpumask = cpumask_of(cpu); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 444 | evt->irq = irq; |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 445 | |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 446 | setup_runstate_info(cpu); |
Jeremy Fitzhardinge | f87e4ca | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 447 | } |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 448 | |
Alex Nixon | d68d82a | 2008-08-22 11:52:15 +0100 | [diff] [blame] | 449 | void xen_teardown_timer(int cpu) |
| 450 | { |
| 451 | struct clock_event_device *evt; |
| 452 | BUG_ON(cpu == 0); |
| 453 | evt = &per_cpu(xen_clock_events, cpu); |
| 454 | unbind_from_irqhandler(evt->irq, NULL); |
| 455 | } |
| 456 | |
Jeremy Fitzhardinge | f87e4ca | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 457 | void xen_setup_cpu_clockevents(void) |
| 458 | { |
| 459 | BUG_ON(preemptible()); |
| 460 | |
| 461 | clockevents_register_device(&__get_cpu_var(xen_clock_events)); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 462 | } |
| 463 | |
Jeremy Fitzhardinge | d07af1f | 2008-05-31 01:33:03 +0100 | [diff] [blame] | 464 | void xen_timer_resume(void) |
| 465 | { |
| 466 | int cpu; |
| 467 | |
| 468 | if (xen_clockevent != &xen_vcpuop_clockevent) |
| 469 | return; |
| 470 | |
| 471 | for_each_online_cpu(cpu) { |
| 472 | if (HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL)) |
| 473 | BUG(); |
| 474 | } |
| 475 | } |
| 476 | |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 477 | __init void xen_time_init(void) |
| 478 | { |
| 479 | int cpu = smp_processor_id(); |
| 480 | |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 481 | clocksource_register(&xen_clocksource); |
| 482 | |
| 483 | if (HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL) == 0) { |
Jeremy Fitzhardinge | f91a8b4 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 484 | /* Successfully turned off 100Hz tick, so we have the |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 485 | vcpuop-based timer interface */ |
| 486 | printk(KERN_DEBUG "Xen: using vcpuop timer interface\n"); |
| 487 | xen_clockevent = &xen_vcpuop_clockevent; |
| 488 | } |
| 489 | |
| 490 | /* Set initial system time with full resolution */ |
| 491 | xen_read_wallclock(&xtime); |
| 492 | set_normalized_timespec(&wall_to_monotonic, |
| 493 | -xtime.tv_sec, -xtime.tv_nsec); |
| 494 | |
Andi Kleen | 404ee5b | 2008-01-30 13:33:20 +0100 | [diff] [blame] | 495 | setup_force_cpu_cap(X86_FEATURE_TSC); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 496 | |
| 497 | xen_setup_timer(cpu); |
Jeremy Fitzhardinge | f87e4ca | 2007-07-17 18:37:06 -0700 | [diff] [blame] | 498 | xen_setup_cpu_clockevents(); |
Jeremy Fitzhardinge | 15c8473 | 2007-07-17 18:37:05 -0700 | [diff] [blame] | 499 | } |