void vmm_scheduler_yield(void)
{
irq_flags_t flags;
struct vmm_scheduler_ctrl *schedp = &this_cpu(sched);
arch_cpu_irq_save(flags);
if (schedp->irq_context) {
vmm_panic("%s: Cannot yield in IRQ context\n", __func__);
}
if (!schedp->current_vcpu) {
vmm_panic("%s: NULL VCPU pointer\n", __func__);
}
if (schedp->current_vcpu->is_normal) {
/* For Normal VCPU
* Just enable yield on exit and rest will be taken care
* by vmm_scheduler_irq_exit()
*/
if (vmm_manager_vcpu_get_state(schedp->current_vcpu) ==
VMM_VCPU_STATE_RUNNING) {
schedp->yield_on_irq_exit = TRUE;
}
} else {
/* For Orphan VCPU
* Forcefully expire yield
*/
arch_vcpu_preempt_orphan();
}
arch_cpu_irq_restore(flags);
}
/**
* sg_copy_buffer - Copy data between a linear buffer and an SG list
* @sgl: The SG list
* @nents: Number of SG entries
* @buf: Where to copy from
* @buflen: The number of bytes to copy
* @to_buffer: transfer direction (non zero == from an sg list to a
* buffer, 0 == from a buffer to an sg list
*
* Returns the number of copied bytes.
*
**/
static size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents,
void *buf, size_t buflen, int to_buffer)
{
unsigned int offset = 0;
struct sg_mapping_iter miter;
unsigned long flags;
unsigned int sg_flags = SG_MITER_ATOMIC;
if (to_buffer)
sg_flags |= SG_MITER_FROM_SG;
else
sg_flags |= SG_MITER_TO_SG;
sg_miter_start(&miter, sgl, nents, sg_flags);
arch_cpu_irq_save(flags);
while (sg_miter_next(&miter) && offset < buflen) {
unsigned int len;
len = min(miter.length, buflen - offset);
if (to_buffer)
memcpy(buf + offset, miter.addr, len);
else
memcpy(miter.addr, buf + offset, len);
offset += len;
}
sg_miter_stop(&miter);
arch_cpu_irq_restore(flags);
return offset;
}
void __lock arch_atomic_sub(atomic_t *atom, long value)
{
irq_flags_t flags;
arch_cpu_irq_save(flags);
atom->counter -= value;
arch_cpu_irq_restore(flags);
}
irq_flags_t __lock vmm_spin_lock_irqsave(vmm_spinlock_t * lock)
{
irq_flags_t flags;
/* Disable and save interrupt flags*/
flags = arch_cpu_irq_save();
#if defined(CONFIG_SMP)
/* Call CPU specific locking routine */
arch_cpu_spin_lock(&lock->__the_lock);
#endif
/* Return saved interrupt flags*/
return flags;
}
long __lock arch_atomic_xchg(atomic_t *atom, long newval)
{
long previous;
irq_flags_t flags;
arch_cpu_irq_save(flags);
previous = atom->counter;
atom->counter = newval;
arch_cpu_irq_restore(flags);
return previous;
}
long __lock arch_atomic_sub_return(atomic_t *atom, long value)
{
long temp;
irq_flags_t flags;
arch_cpu_irq_save(flags);
atom->counter -= value;
temp = atom->counter;
arch_cpu_irq_restore(flags);
return temp;
}
long __lock arch_atomic_cmpxchg(atomic_t *atom, long oldval, long newval)
{
long previous;
irq_flags_t flags;
arch_cpu_irq_save(flags);
previous = atom->counter;
if (previous == oldval) {
atom->counter = newval;
}
arch_cpu_irq_restore(flags);
return previous;
}
bool vmm_scheduler_normal_context(void)
{
bool ret = FALSE;
irq_flags_t flags;
struct vmm_scheduler_ctrl *schedp = &this_cpu(sched);
arch_cpu_irq_save(flags);
if (schedp->current_vcpu && !schedp->irq_context) {
ret = (schedp->current_vcpu->is_normal) ? TRUE : FALSE;
}
arch_cpu_irq_restore(flags);
return ret;
}
int vmm_profiler_stop(void)
{
if (vmm_profiler_isactive()) {
irq_flags_t flags = arch_cpu_irq_save();
_vmm_profile_enter = vmm_profile_none;
_vmm_profile_exit = vmm_profile_none;
pctrl.is_active = 0;
arch_cpu_irq_restore(flags);
} else {
return VMM_EFAIL;
}
return VMM_OK;
}
void vmm_scheduler_preempt_enable(void)
{
irq_flags_t flags;
struct vmm_vcpu *vcpu;
struct vmm_scheduler_ctrl *schedp = &this_cpu(sched);
arch_cpu_irq_save(flags);
if (!schedp->irq_context) {
vcpu = schedp->current_vcpu;
if (vcpu && vcpu->preempt_count) {
vcpu->preempt_count--;
}
}
arch_cpu_irq_restore(flags);
}
int vmm_profiler_start(void)
{
if (!vmm_profiler_isactive()) {
irq_flags_t flags = arch_cpu_irq_save();
vmm_memset(pctrl.stat, 0,
sizeof(struct vmm_profiler_stat) *
kallsyms_num_syms);
_vmm_profile_enter = vmm_profile_enter;
_vmm_profile_exit = vmm_profile_exit;
pctrl.is_active = 1;
arch_cpu_irq_restore(flags);
} else {
return VMM_EFAIL;
}
return VMM_OK;
}
static void epit_set_mode(enum vmm_clockchip_mode mode,
struct vmm_clockchip *evt)
{
struct epit_clockchip *ecc = evt->priv;
unsigned long flags;
/*
* The timer interrupt generation is disabled at least
* for enough time to call epit_set_next_event()
*/
arch_cpu_irq_save(flags);
/* Disable interrupt */
epit_irq_disable(ecc);
if (mode != ecc->clockevent_mode) {
/*
* Set event time into far-far future.
* The further we can go is to let the timer wrap arround
* once.
*/
/* read the actual counter */
unsigned long tcmp = vmm_readl((void *)(ecc->base + EPITCNR));
/*
* add 1 (as the counter is decrementing) and write the
* value.
*/
vmm_writel(tcmp + 1, (void *)(ecc->base + EPITCMPR));
/* Clear pending interrupt */
epit_irq_acknowledge(ecc);
}
/* Remember timer mode */
ecc->clockevent_mode = mode;
arch_cpu_irq_restore(flags);
switch (mode) {
case VMM_CLOCKCHIP_MODE_PERIODIC:
vmm_printf("epit_set_mode: Periodic mode is not "
"supported for i.MX EPIT\n");
break;
case VMM_CLOCKCHIP_MODE_ONESHOT:
/*
* Do not put overhead of interrupt enable/disable into
* epit_set_next_event(), the core has about 4 minutes
* to call epit_set_next_event() or shutdown clock after
* mode switching
*/
arch_cpu_irq_save(flags);
epit_irq_enable(ecc);
arch_cpu_irq_restore(flags);
break;
case VMM_CLOCKCHIP_MODE_SHUTDOWN:
case VMM_CLOCKCHIP_MODE_UNUSED:
case VMM_CLOCKCHIP_MODE_RESUME:
/* Left event sources disabled, no more interrupts appear */
break;
}
}
