adjust the way that idle happens so as to avoid missing timer interrupts
This commit is contained in:
Kip Macy
parent
e545eedd7d
commit
bd1c698cab
@ -246,24 +246,29 @@ static void __get_time_values_from_xen(void)
|
||||
shared_info_t *s = HYPERVISOR_shared_info;
|
||||
struct vcpu_time_info *src;
|
||||
struct shadow_time_info *dst;
|
||||
uint32_t pre_version, post_version;
|
||||
|
||||
src = &s->vcpu_info[smp_processor_id()].time;
|
||||
dst = &per_cpu(shadow_time, smp_processor_id());
|
||||
|
||||
spinlock_enter();
|
||||
do {
|
||||
dst->version = src->version;
|
||||
pre_version = dst->version = src->version;
|
||||
rmb();
|
||||
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();
|
||||
post_version = src->version;
|
||||
}
|
||||
while ((src->version & 1) | (dst->version ^ src->version));
|
||||
while ((pre_version & 1) | (pre_version ^ post_version));
|
||||
|
||||
dst->tsc_to_usec_mul = dst->tsc_to_nsec_mul / 1000;
|
||||
spinlock_exit();
|
||||
}
|
||||
|
||||
|
||||
static inline int time_values_up_to_date(int cpu)
|
||||
{
|
||||
struct vcpu_time_info *src;
|
||||
@ -311,15 +316,15 @@ clkintr(void *arg)
|
||||
}
|
||||
|
||||
/* Process elapsed ticks since last call. */
|
||||
if (delta >= NS_PER_TICK) {
|
||||
processed_system_time += (delta / NS_PER_TICK) * NS_PER_TICK;
|
||||
per_cpu(processed_system_time, cpu) += (delta_cpu / NS_PER_TICK) * NS_PER_TICK;
|
||||
while (delta >= NS_PER_TICK) {
|
||||
delta -= NS_PER_TICK;
|
||||
processed_system_time += NS_PER_TICK;
|
||||
per_cpu(processed_system_time, cpu) += NS_PER_TICK;
|
||||
if (PCPU_GET(cpuid) == 0)
|
||||
hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
|
||||
else
|
||||
hardclock_cpu(TRAPF_USERMODE(frame));
|
||||
}
|
||||
if (PCPU_GET(cpuid) == 0)
|
||||
hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
|
||||
else
|
||||
hardclock_cpu(TRAPF_USERMODE(frame));
|
||||
|
||||
/*
|
||||
* Take synchronised time from Xen once a minute if we're not
|
||||
* synchronised ourselves, and we haven't chosen to keep an independent
|
||||
@ -334,61 +339,25 @@ clkintr(void *arg)
|
||||
/* XXX TODO */
|
||||
return (FILTER_HANDLED);
|
||||
}
|
||||
|
||||
int clkintr2(void *arg);
|
||||
|
||||
int
|
||||
clkintr2(void *arg)
|
||||
{
|
||||
int64_t delta_cpu, delta;
|
||||
struct trapframe *frame = (struct trapframe *)arg;
|
||||
int cpu = smp_processor_id();
|
||||
struct shadow_time_info *shadow = &per_cpu(shadow_time, cpu);
|
||||
|
||||
do {
|
||||
__get_time_values_from_xen();
|
||||
|
||||
delta = delta_cpu =
|
||||
shadow->system_timestamp + get_nsec_offset(shadow);
|
||||
delta -= processed_system_time;
|
||||
delta_cpu -= per_cpu(processed_system_time, cpu);
|
||||
|
||||
} while (!time_values_up_to_date(cpu));
|
||||
|
||||
if (unlikely(delta < (int64_t)0) || unlikely(delta_cpu < (int64_t)0)) {
|
||||
printf("Timer ISR: Time went backwards: %lld\n", delta);
|
||||
return (FILTER_HANDLED);
|
||||
}
|
||||
|
||||
/* Process elapsed ticks since last call. */
|
||||
if (delta >= NS_PER_TICK) {
|
||||
processed_system_time += (delta / NS_PER_TICK) * NS_PER_TICK;
|
||||
per_cpu(processed_system_time, cpu) += (delta_cpu / NS_PER_TICK) * NS_PER_TICK;
|
||||
}
|
||||
hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
|
||||
|
||||
/*
|
||||
* Take synchronised time from Xen once a minute if we're not
|
||||
* synchronised ourselves, and we haven't chosen to keep an independent
|
||||
* time base.
|
||||
*/
|
||||
|
||||
if (shadow_tv_version != HYPERVISOR_shared_info->wc_version) {
|
||||
update_wallclock();
|
||||
tc_setclock(&shadow_tv);
|
||||
}
|
||||
|
||||
/* XXX TODO */
|
||||
return (FILTER_HANDLED);
|
||||
}
|
||||
|
||||
static uint32_t
|
||||
getit(void)
|
||||
{
|
||||
struct shadow_time_info *shadow;
|
||||
uint64_t time;
|
||||
uint32_t local_time_version;
|
||||
|
||||
shadow = &per_cpu(shadow_time, smp_processor_id());
|
||||
__get_time_values_from_xen();
|
||||
return shadow->system_timestamp + get_nsec_offset(shadow);
|
||||
|
||||
do {
|
||||
local_time_version = shadow->version;
|
||||
barrier();
|
||||
time = shadow->system_timestamp + get_nsec_offset(shadow);
|
||||
if (!time_values_up_to_date(cpu))
|
||||
__get_time_values_from_xen(/*cpu */);
|
||||
barrier();
|
||||
} while (local_time_version != shadow->version);
|
||||
|
||||
return (time);
|
||||
}
|
||||
|
||||
|
||||
@ -552,7 +521,6 @@ startrtclock()
|
||||
timer_freq = xen_timecounter.tc_frequency = 1000000000LL;
|
||||
tc_init(&xen_timecounter);
|
||||
|
||||
|
||||
rdtscll(alarm);
|
||||
}
|
||||
|
||||
@ -903,13 +871,44 @@ xen_get_offset(void)
|
||||
return edx;
|
||||
}
|
||||
#endif
|
||||
|
||||
/* Convert jiffies to system time. */
|
||||
static uint64_t
|
||||
ticks_to_system_time(unsigned long newticks)
|
||||
{
|
||||
#if 0
|
||||
unsigned long seq;
|
||||
#endif
|
||||
long delta;
|
||||
uint64_t st;
|
||||
|
||||
|
||||
delta = newticks - ticks;
|
||||
if (delta < 1) {
|
||||
/* Triggers in some wrap-around cases, but that's okay:
|
||||
* we just end up with a shorter timeout. */
|
||||
st = processed_system_time + NS_PER_TICK;
|
||||
} else if (((unsigned long)delta >> (BITS_PER_LONG-3)) != 0) {
|
||||
/* Very long timeout means there is no pending timer.
|
||||
* We indicate this to Xen by passing zero timeout. */
|
||||
st = 0;
|
||||
} else {
|
||||
st = processed_system_time + delta * (uint64_t)NS_PER_TICK;
|
||||
}
|
||||
|
||||
return (st);
|
||||
}
|
||||
|
||||
void
|
||||
idle_block(void)
|
||||
{
|
||||
uint64_t timeout;
|
||||
|
||||
__get_time_values_from_xen();
|
||||
PANIC_IF(HYPERVISOR_set_timer_op(processed_system_time + NS_PER_TICK) != 0);
|
||||
HYPERVISOR_sched_op(SCHEDOP_block, 0);
|
||||
timeout = ticks_to_system_time(ticks + 1) + NS_PER_TICK/2;
|
||||
|
||||
__get_time_values_from_xen();
|
||||
PANIC_IF(HYPERVISOR_set_timer_op(timeout) != 0);
|
||||
HYPERVISOR_sched_op(SCHEDOP_block, 0);
|
||||
}
|
||||
|
||||
int
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user