/*
* Start the HZ tick on the current CPU.
* Only cpu_idle may call this function.
*/
static void start_hz_timer(void)
{
BUG_ON(!in_interrupt());
if (!cpu_isset(smp_processor_id(), nohz_cpu_mask))
return;
account_ticks(get_clock());
set_clock_comparator(S390_lowcore.jiffy_timer + CPU_DEVIATION);
cpu_clear(smp_processor_id(), nohz_cpu_mask);
}
/*
* do_IRQ() handles all normal I/O device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
* handlers).
*
*/
void
do_IRQ (struct pt_regs *regs)
{
struct tpi_info *tpi_info;
struct subchannel *sch;
struct irb *irb;
irq_enter ();
asm volatile ("mc 0,0");
if (S390_lowcore.int_clock >= S390_lowcore.jiffy_timer)
/**
* Make sure that the i/o interrupt did not "overtake"
* the last HZ timer interrupt.
*/
account_ticks(regs);
/*
* Get interrupt information from lowcore
*/
tpi_info = (struct tpi_info *) __LC_SUBCHANNEL_ID;
irb = (struct irb *) __LC_IRB;
do {
kstat_cpu(smp_processor_id()).irqs[IO_INTERRUPT]++;
/*
* Non I/O-subchannel thin interrupts are processed differently
*/
if (tpi_info->adapter_IO == 1 &&
tpi_info->int_type == IO_INTERRUPT_TYPE) {
do_adapter_IO();
continue;
}
sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
if (sch)
spin_lock(&sch->lock);
/* Store interrupt response block to lowcore. */
if (tsch (tpi_info->irq, irb) == 0 && sch) {
/* Keep subchannel information word up to date. */
memcpy (&sch->schib.scsw, &irb->scsw,
sizeof (irb->scsw));
/* Call interrupt handler if there is one. */
if (sch->driver && sch->driver->irq)
sch->driver->irq(&sch->dev);
}
if (sch)
spin_unlock(&sch->lock);
/*
* Are more interrupts pending?
* If so, the tpi instruction will update the lowcore
* to hold the info for the next interrupt.
* We don't do this for VM because a tpi drops the cpu
* out of the sie which costs more cycles than it saves.
*/
} while (!MACHINE_IS_VM && tpi (NULL) != 0);
irq_exit ();
}
void do_extint(struct pt_regs *regs, unsigned short code)
{
ext_int_info_t *p;
int index;
irq_enter();
if (S390_lowcore.int_clock >= S390_lowcore.jiffy_timer)
account_ticks(regs);
kstat_cpu(smp_processor_id()).irqs[EXTERNAL_INTERRUPT]++;
index = code & 0xff;
for (p = ext_int_hash[index]; p; p = p->next) {
if (likely(p->code == code)) {
if (likely(p->handler))
p->handler(regs, code);
}
}
irq_exit();
}
void do_extint(struct pt_regs *regs, unsigned short code)
{
ext_int_info_t *p;
int index;
irq_enter();
asm volatile ("mc 0,0");
if (S390_lowcore.int_clock >= S390_lowcore.jiffy_timer)
/**
* Make sure that the i/o interrupt did not "overtake"
* the last HZ timer interrupt.
*/
account_ticks(regs);
kstat_cpu(smp_processor_id()).irqs[EXTERNAL_INTERRUPT]++;
index = code & 0xff;
for (p = ext_int_hash[index]; p; p = p->next) {
if (likely(p->code == code)) {
if (likely(p->handler))
p->handler(regs, code);
}
}
irq_exit();
}
