X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=arch%2Fx86%2Fxen%2Ftime.c;h=b3c6c59ed302862ecde2b2b78f88287954db991d;hb=9a9620db07b27700a4de9e86985735fffb78e2f8;hp=c39e1a5aa241bcce2cb2a070d2dbbe391a28ae31;hpb=359cdd3f866b6219a6729e313faf2221397f3278;p=safe%2Fjmp%2Flinux-2.6 diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index c39e1a5..b3c6c59 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -12,7 +12,10 @@ #include #include #include +#include +#include +#include #include #include @@ -28,28 +31,15 @@ #define TIMER_SLOP 100000 #define NS_PER_TICK (1000000000LL / HZ) -static cycle_t xen_clocksource_read(void); - -/* These are perodically updated in shared_info, and then copied here. */ -struct shadow_time_info { - u64 tsc_timestamp; /* TSC at last update of time vals. */ - u64 system_timestamp; /* Time, in nanosecs, since boot. */ - u32 tsc_to_nsec_mul; - int tsc_shift; - u32 version; -}; - -static DEFINE_PER_CPU(struct shadow_time_info, shadow_time); - /* runstate info updated by Xen */ -static DEFINE_PER_CPU(struct vcpu_runstate_info, runstate); +static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate); /* snapshots of runstate info */ -static DEFINE_PER_CPU(struct vcpu_runstate_info, runstate_snapshot); +static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate_snapshot); /* unused ns of stolen and blocked time */ -static DEFINE_PER_CPU(u64, residual_stolen); -static DEFINE_PER_CPU(u64, residual_blocked); +static DEFINE_PER_CPU(u64, xen_residual_stolen); +static DEFINE_PER_CPU(u64, xen_residual_blocked); /* return an consistent snapshot of 64-bit time/counter value */ static u64 get64(const u64 *p) @@ -90,7 +80,7 @@ static void get_runstate_snapshot(struct vcpu_runstate_info *res) BUG_ON(preemptible()); - state = &__get_cpu_var(runstate); + state = &__get_cpu_var(xen_runstate); /* * The runstate info is always updated by the hypervisor on @@ -108,14 +98,14 @@ static void get_runstate_snapshot(struct vcpu_runstate_info *res) /* return true when a vcpu could run but has no real cpu to run on */ bool xen_vcpu_stolen(int vcpu) { - return per_cpu(runstate, vcpu).state == RUNSTATE_runnable; + return per_cpu(xen_runstate, vcpu).state == RUNSTATE_runnable; } -static void setup_runstate_info(int cpu) +void xen_setup_runstate_info(int cpu) { struct vcpu_register_runstate_memory_area area; - area.addr.v = &per_cpu(runstate, cpu); + area.addr.v = &per_cpu(xen_runstate, cpu); if (HYPERVISOR_vcpu_op(VCPUOP_register_runstate_memory_area, cpu, &area)) @@ -133,7 +123,7 @@ static void do_stolen_accounting(void) WARN_ON(state.state != RUNSTATE_running); - snap = &__get_cpu_var(runstate_snapshot); + snap = &__get_cpu_var(xen_runstate_snapshot); /* work out how much time the VCPU has not been runn*ing* */ blocked = state.time[RUNSTATE_blocked] - snap->time[RUNSTATE_blocked]; @@ -143,36 +133,26 @@ static void do_stolen_accounting(void) *snap = state; /* Add the appropriate number of ticks of stolen time, - including any left-overs from last time. Passing NULL to - account_steal_time accounts the time as stolen. */ - stolen = runnable + offline + __get_cpu_var(residual_stolen); + including any left-overs from last time. */ + stolen = runnable + offline + __get_cpu_var(xen_residual_stolen); if (stolen < 0) stolen = 0; - ticks = 0; - while (stolen >= NS_PER_TICK) { - ticks++; - stolen -= NS_PER_TICK; - } - __get_cpu_var(residual_stolen) = stolen; - account_steal_time(NULL, ticks); + ticks = iter_div_u64_rem(stolen, NS_PER_TICK, &stolen); + __get_cpu_var(xen_residual_stolen) = stolen; + account_steal_ticks(ticks); /* Add the appropriate number of ticks of blocked time, - including any left-overs from last time. Passing idle to - account_steal_time accounts the time as idle/wait. */ - blocked += __get_cpu_var(residual_blocked); + including any left-overs from last time. */ + blocked += __get_cpu_var(xen_residual_blocked); if (blocked < 0) blocked = 0; - ticks = 0; - while (blocked >= NS_PER_TICK) { - ticks++; - blocked -= NS_PER_TICK; - } - __get_cpu_var(residual_blocked) = blocked; - account_steal_time(idle_task(smp_processor_id()), ticks); + ticks = iter_div_u64_rem(blocked, NS_PER_TICK, &blocked); + __get_cpu_var(xen_residual_blocked) = blocked; + account_idle_ticks(ticks); } /* @@ -214,137 +194,40 @@ unsigned long long xen_sched_clock(void) } -/* Get the CPU speed from Xen */ -unsigned long xen_cpu_khz(void) +/* Get the TSC speed from Xen */ +unsigned long xen_tsc_khz(void) { - u64 xen_khz = 1000000ULL << 32; - const struct vcpu_time_info *info = + struct pvclock_vcpu_time_info *info = &HYPERVISOR_shared_info->vcpu_info[0].time; - do_div(xen_khz, info->tsc_to_system_mul); - if (info->tsc_shift < 0) - xen_khz <<= -info->tsc_shift; - else - xen_khz >>= info->tsc_shift; - - return xen_khz; + return pvclock_tsc_khz(info); } -/* - * Reads a consistent set of time-base values from Xen, into a shadow data - * area. - */ -static unsigned get_time_values_from_xen(void) +cycle_t xen_clocksource_read(void) { - struct vcpu_time_info *src; - struct shadow_time_info *dst; - - /* src is shared memory with the hypervisor, so we need to - make sure we get a consistent snapshot, even in the face of - being preempted. */ - src = &__get_cpu_var(xen_vcpu)->time; - dst = &__get_cpu_var(shadow_time); - - do { - dst->version = src->version; - rmb(); /* fetch version before data */ - dst->tsc_timestamp = src->tsc_timestamp; - dst->system_timestamp = src->system_time; - dst->tsc_to_nsec_mul = src->tsc_to_system_mul; - dst->tsc_shift = src->tsc_shift; - rmb(); /* test version after fetching data */ - } while ((src->version & 1) | (dst->version ^ src->version)); - - return dst->version; -} + struct pvclock_vcpu_time_info *src; + cycle_t ret; -/* - * Scale a 64-bit delta by scaling and multiplying by a 32-bit fraction, - * yielding a 64-bit result. - */ -static inline u64 scale_delta(u64 delta, u32 mul_frac, int shift) -{ - u64 product; -#ifdef __i386__ - u32 tmp1, tmp2; -#endif - - if (shift < 0) - delta >>= -shift; - else - delta <<= shift; - -#ifdef __i386__ - __asm__ ( - "mul %5 ; " - "mov %4,%%eax ; " - "mov %%edx,%4 ; " - "mul %5 ; " - "xor %5,%5 ; " - "add %4,%%eax ; " - "adc %5,%%edx ; " - : "=A" (product), "=r" (tmp1), "=r" (tmp2) - : "a" ((u32)delta), "1" ((u32)(delta >> 32)), "2" (mul_frac) ); -#elif __x86_64__ - __asm__ ( - "mul %%rdx ; shrd $32,%%rdx,%%rax" - : "=a" (product) : "0" (delta), "d" ((u64)mul_frac) ); -#else -#error implement me! -#endif - - return product; + src = &get_cpu_var(xen_vcpu)->time; + ret = pvclock_clocksource_read(src); + put_cpu_var(xen_vcpu); + return ret; } -static u64 get_nsec_offset(struct shadow_time_info *shadow) +static cycle_t xen_clocksource_get_cycles(struct clocksource *cs) { - u64 now, delta; - now = native_read_tsc(); - delta = now - shadow->tsc_timestamp; - return scale_delta(delta, shadow->tsc_to_nsec_mul, shadow->tsc_shift); -} - -static cycle_t xen_clocksource_read(void) -{ - struct shadow_time_info *shadow = &get_cpu_var(shadow_time); - cycle_t ret; - unsigned version; - - do { - version = get_time_values_from_xen(); - barrier(); - ret = shadow->system_timestamp + get_nsec_offset(shadow); - barrier(); - } while (version != __get_cpu_var(xen_vcpu)->time.version); - - put_cpu_var(shadow_time); - - return ret; + return xen_clocksource_read(); } static void xen_read_wallclock(struct timespec *ts) { - const struct shared_info *s = HYPERVISOR_shared_info; - u32 version; - u64 delta; - struct timespec now; - - /* get wallclock at system boot */ - do { - version = s->wc_version; - rmb(); /* fetch version before time */ - now.tv_sec = s->wc_sec; - now.tv_nsec = s->wc_nsec; - rmb(); /* fetch time before checking version */ - } while ((s->wc_version & 1) | (version ^ s->wc_version)); - - delta = xen_clocksource_read(); /* time since system boot */ - delta += now.tv_sec * (u64)NSEC_PER_SEC + now.tv_nsec; - - now.tv_nsec = do_div(delta, NSEC_PER_SEC); - now.tv_sec = delta; + struct shared_info *s = HYPERVISOR_shared_info; + struct pvclock_wall_clock *wall_clock = &(s->wc); + struct pvclock_vcpu_time_info *vcpu_time; - set_normalized_timespec(ts, now.tv_sec, now.tv_nsec); + vcpu_time = &get_cpu_var(xen_vcpu)->time; + pvclock_read_wallclock(wall_clock, vcpu_time, ts); + put_cpu_var(xen_vcpu); } unsigned long xen_get_wallclock(void) @@ -352,7 +235,6 @@ unsigned long xen_get_wallclock(void) struct timespec ts; xen_read_wallclock(&ts); - return ts.tv_sec; } @@ -365,7 +247,7 @@ int xen_set_wallclock(unsigned long now) static struct clocksource xen_clocksource __read_mostly = { .name = "xen", .rating = 400, - .read = xen_clocksource_read, + .read = xen_clocksource_get_cycles, .mask = ~0, .mult = 1<cpumask = cpumask_of_cpu(cpu); + evt->cpumask = cpumask_of(cpu); evt->irq = irq; +} - setup_runstate_info(cpu); +void xen_teardown_timer(int cpu) +{ + struct clock_event_device *evt; + BUG_ON(cpu == 0); + evt = &per_cpu(xen_clock_events, cpu); + unbind_from_irqhandler(evt->irq, NULL); } void xen_setup_cpu_clockevents(void) @@ -572,11 +460,23 @@ void xen_setup_cpu_clockevents(void) clockevents_register_device(&__get_cpu_var(xen_clock_events)); } +void xen_timer_resume(void) +{ + int cpu; + + if (xen_clockevent != &xen_vcpuop_clockevent) + return; + + for_each_online_cpu(cpu) { + if (HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL)) + BUG(); + } +} + __init void xen_time_init(void) { int cpu = smp_processor_id(); - - get_time_values_from_xen(); + struct timespec tp; clocksource_register(&xen_clocksource); @@ -588,12 +488,12 @@ __init void xen_time_init(void) } /* Set initial system time with full resolution */ - xen_read_wallclock(&xtime); - set_normalized_timespec(&wall_to_monotonic, - -xtime.tv_sec, -xtime.tv_nsec); + xen_read_wallclock(&tp); + do_settimeofday(&tp); setup_force_cpu_cap(X86_FEATURE_TSC); + xen_setup_runstate_info(cpu); xen_setup_timer(cpu); xen_setup_cpu_clockevents(); }