void switch_APIC_timer_to_ipi(void *cpumask)
{
cpumask_t mask = *(cpumask_t *)cpumask;
int cpu = smp_processor_id();
if (cpu_isset(cpu, mask) &&
!cpu_isset(cpu, timer_bcast_ipi)) {
disable_APIC_timer();
cpu_set(cpu, timer_bcast_ipi);
}
}
void switch_APIC_timer_to_ipi(void *cpumask)
{
cpumask_t mask = *(cpumask_t *)cpumask;
int cpu = smp_processor_id();
if (cpu_isset(cpu, mask) &&
!cpu_isset(cpu, timer_interrupt_broadcast_ipi_mask)) {
disable_APIC_timer();
cpu_set(cpu, timer_interrupt_broadcast_ipi_mask);
#ifdef CONFIG_HIGH_RES_TIMERS
printk("Disabling NO_HZ and high resolution timers "
"due to timer broadcasting\n");
for_each_possible_cpu(cpu)
per_cpu(lapic_events, cpu).features &=
~CLOCK_EVT_FEAT_ONESHOT;
#endif
}
}
static void __init smp_callin(void)
{
int cpuid, phys_id;
unsigned long timeout;
/*
* If waken up by an INIT in an 82489DX configuration
* we may get here before an INIT-deassert IPI reaches
* our local APIC. We have to wait for the IPI or we'll
* lock up on an APIC access.
*/
wait_for_init_deassert(&init_deasserted);
/*
* (This works even if the APIC is not enabled.)
*/
phys_id = GET_APIC_ID(apic_read(APIC_ID));
cpuid = smp_processor_id();
if (cpu_isset(cpuid, cpu_callin_map)) {
printk("huh, phys CPU#%d, CPU#%d already present??\n",
phys_id, cpuid);
BUG();
}
Dprintk("CPU#%d (phys ID: %d) waiting for CALLOUT\n", cpuid, phys_id);
/*
* STARTUP IPIs are fragile beasts as they might sometimes
* trigger some glue motherboard logic. Complete APIC bus
* silence for 1 second, this overestimates the time the
* boot CPU is spending to send the up to 2 STARTUP IPIs
* by a factor of two. This should be enough.
*/
/*
* Waiting 2s total for startup (udelay is not yet working)
*/
timeout = jiffies + 2*HZ;
while (time_before(jiffies, timeout)) {
/*
* Has the boot CPU finished it's STARTUP sequence?
*/
if (cpu_isset(cpuid, cpu_callout_map))
break;
rep_nop();
}
if (!time_before(jiffies, timeout)) {
printk("BUG: CPU%d started up but did not get a callout!\n",
cpuid);
BUG();
}
/*
* the boot CPU has finished the init stage and is spinning
* on callin_map until we finish. We are free to set up this
* CPU, first the APIC. (this is probably redundant on most
* boards)
*/
Dprintk("CALLIN, before setup_local_APIC().\n");
smp_callin_clear_local_apic();
setup_local_APIC();
map_cpu_to_logical_apicid();
/*
* Get our bogomips.
*/
calibrate_delay();
Dprintk("Stack at about %p\n",&cpuid);
/*
* Save our processor parameters
*/
smp_store_cpu_info(cpuid);
disable_APIC_timer();
/*
* Allow the master to continue.
*/
cpu_set(cpuid, cpu_callin_map);
/*
* Synchronize the TSC with the BP
*/
if (cpu_has_tsc && cpu_khz)
synchronize_tsc_ap();
}
