static int irq_affinity_write_proc(struct file *file, const char __user *buffer,
unsigned long count, void *data)
{
unsigned int irq = (int)(long)data, full_count = count, err;
cpumask_t new_value, tmp;
if (!irq_desc[irq].chip->set_affinity || no_irq_affinity ||
CHECK_IRQ_PER_CPU(irq_desc[irq].status))
return -EIO;
err = cpumask_parse_user(buffer, count, new_value);
if (err)
return err;
/*
* Do not allow disabling IRQs completely - it's a too easy
* way to make the system unusable accidentally :-) At least
* one online CPU still has to be targeted.
*/
cpus_and(tmp, new_value, cpu_online_map);
if (cpus_empty(tmp))
/* Special case for empty set - allow the architecture
code to set default SMP affinity. */
return select_smp_affinity(irq) ? -EINVAL : full_count;
proc_set_irq_affinity(irq, new_value);
return full_count;
}
/**
* irq_can_set_affinity - Check if the affinity of a given irq can be set
* @irq: Interrupt to check
*
*/
int irq_can_set_affinity(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
if (CHECK_IRQ_PER_CPU(desc->status) || !desc->irq_data.chip ||
!desc->irq_data.chip->irq_set_affinity)
return 0;
return 1;
}
void move_masked_irq(int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
if (likely(!(desc->status & IRQ_MOVE_PENDING)))
return;
/*
* Paranoia: cpu-local interrupts shouldn't be calling in here anyway.
*/
if (CHECK_IRQ_PER_CPU(desc->status)) {
WARN_ON(1);
return;
}
desc->status &= ~IRQ_MOVE_PENDING;
if (unlikely(cpumask_empty(desc->pending_mask)))
return;
if (!desc->chip->set_affinity)
return;
assert_spin_locked(&desc->lock);
/*
* If there was a valid mask to work with, please
* do the disable, re-program, enable sequence.
* This is *not* particularly important for level triggered
* but in a edge trigger case, we might be setting rte
* when an active trigger is comming in. This could
* cause some ioapics to mal-function.
* Being paranoid i guess!
*
* For correct operation this depends on the caller
* masking the irqs.
*/
if (likely(cpumask_any_and(desc->pending_mask, cpu_online_mask)
< nr_cpu_ids)) {
int ret = chip->irq_set_affinity(irq, desc->pending_mask);
switch (ret) {
case IRQ_SET_MASK_OK:
cpumask_copy(desc->affinity, desc->pending_mask);
case IRQ_SET_MASK_OK_NOCOPY:
irq_set_thread_affinity(desc);
}
}
cpumask_clear(desc->pending_mask);
}
int cpu_check_affinity(unsigned int irq, const struct cpumask *dest)
{
int cpu_dest;
/* timer and ipi have to always be received on all CPUs */
if (CHECK_IRQ_PER_CPU(irq)) {
/* Bad linux design decision. The mask has already
* been set; we must reset it */
cpumask_setall(irq_desc[irq].affinity);
return -EINVAL;
}
/* whatever mask they set, we just allow one CPU */
cpu_dest = first_cpu(*dest);
return cpu_dest;
}
void move_masked_irq(int irq)
{
struct irq_desc *desc = irq_desc + irq;
cpumask_t tmp;
if (likely(!(desc->status & IRQ_MOVE_PENDING)))
return;
/*
* Paranoia: cpu-local interrupts shouldn't be calling in here anyway.
*/
if (CHECK_IRQ_PER_CPU(desc->status)) {
WARN_ON(1);
return;
}
desc->status &= ~IRQ_MOVE_PENDING;
if (unlikely(cpus_empty(irq_desc[irq].pending_mask)))
return;
if (!desc->chip->set_affinity)
return;
assert_spin_locked(&desc->lock);
cpus_and(tmp, irq_desc[irq].pending_mask, cpu_online_map);
/*
* If there was a valid mask to work with, please
* do the disable, re-program, enable sequence.
* This is *not* particularly important for level triggered
* but in a edge trigger case, we might be setting rte
* when an active trigger is comming in. This could
* cause some ioapics to mal-function.
* Being paranoid i guess!
*
* For correct operation this depends on the caller
* masking the irqs.
*/
if (likely(!cpus_empty(tmp))) {
desc->chip->set_affinity(irq,tmp);
}
cpus_clear(irq_desc[irq].pending_mask);
}
/* ONLY called from entry.S:intr_extint() */
void do_cpu_irq_mask(struct pt_regs *regs)
{
struct pt_regs *old_regs;
unsigned long eirr_val;
int irq, cpu = smp_processor_id();
#ifdef CONFIG_SMP
cpumask_t dest;
#endif
old_regs = set_irq_regs(regs);
local_irq_disable();
irq_enter();
eirr_val = mfctl(23) & cpu_eiem & per_cpu(local_ack_eiem, cpu);
if (!eirr_val)
goto set_out;
irq = eirr_to_irq(eirr_val);
#ifdef CONFIG_SMP
cpumask_copy(&dest, irq_desc[irq].affinity);
if (CHECK_IRQ_PER_CPU(irq_desc[irq].status) &&
!cpu_isset(smp_processor_id(), dest)) {
int cpu = first_cpu(dest);
printk(KERN_DEBUG "redirecting irq %d from CPU %d to %d\n",
irq, smp_processor_id(), cpu);
gsc_writel(irq + CPU_IRQ_BASE,
per_cpu(cpu_data, cpu).hpa);
goto set_out;
}
#endif
__do_IRQ(irq);
out:
irq_exit();
set_irq_regs(old_regs);
return;
set_out:
set_eiem(cpu_eiem & per_cpu(local_ack_eiem, cpu));
goto out;
}
/**
* __do_IRQ - original all in one highlevel IRQ handler
* @irq: the interrupt number
*
* __do_IRQ handles all normal device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
* handlers).
*
* This is the original x86 implementation which is used for every
* interrupt type.
*/
unsigned int __do_IRQ(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
struct irqaction *action;
unsigned int status;
kstat_incr_irqs_this_cpu(irq, desc);
if (CHECK_IRQ_PER_CPU(desc->status)) {
irqreturn_t action_ret;
/*
* No locking required for CPU-local interrupts:
*/
if (desc->chip->ack)
desc->chip->ack(irq);
if (likely(!(desc->status & IRQ_DISABLED))) {
action_ret = handle_IRQ_event(irq, desc->action);
if (!noirqdebug)
note_interrupt(irq, desc, action_ret);
}
desc->chip->end(irq);
return 1;
}
spin_lock(&desc->lock);
if (desc->chip->ack)
desc->chip->ack(irq);
/*
* REPLAY is when Linux resends an IRQ that was dropped earlier
* WAITING is used by probe to mark irqs that are being tested
*/
status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING);
status |= IRQ_PENDING; /* we _want_ to handle it */
/*
* If the IRQ is disabled for whatever reason, we cannot
* use the action we have.
*/
action = NULL;
if (likely(!(status & (IRQ_DISABLED | IRQ_INPROGRESS)))) {
action = desc->action;
status &= ~IRQ_PENDING; /* we commit to handling */
status |= IRQ_INPROGRESS; /* we are handling it */
}
desc->status = status;
/*
* If there is no IRQ handler or it was disabled, exit early.
* Since we set PENDING, if another processor is handling
* a different instance of this same irq, the other processor
* will take care of it.
*/
if (unlikely(!action))
goto out;
/*
* Edge triggered interrupts need to remember
* pending events.
* This applies to any hw interrupts that allow a second
* instance of the same irq to arrive while we are in do_IRQ
* or in the handler. But the code here only handles the _second_
* instance of the irq, not the third or fourth. So it is mostly
* useful for irq hardware that does not mask cleanly in an
* SMP environment.
*/
for (;;) {
irqreturn_t action_ret;
spin_unlock(&desc->lock);
action_ret = handle_IRQ_event(irq, action);
if (!noirqdebug)
note_interrupt(irq, desc, action_ret);
spin_lock(&desc->lock);
if (likely(!(desc->status & IRQ_PENDING)))
break;
desc->status &= ~IRQ_PENDING;
}
desc->status &= ~IRQ_INPROGRESS;
out:
/*
* The ->end() handler has to deal with interrupts which got
* disabled while the handler was running.
*/
desc->chip->end(irq);
spin_unlock(&desc->lock);
return 1;
}
/**
* __do_IRQ - original all in one highlevel IRQ handler
* @irq: the interrupt number
* @regs: pointer to a register structure
*
* __do_IRQ handles all normal device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
* handlers).
*
* This is the original x86 implementation which is used for every
* interrupt type.
*/
fastcall notrace unsigned int __do_IRQ(unsigned int irq, struct pt_regs *regs)
{
struct irq_desc *desc = irq_desc + irq;
struct irqaction *action;
unsigned int status;
kstat_this_cpu.irqs[irq]++;
if (CHECK_IRQ_PER_CPU(desc->status)) {
irqreturn_t action_ret;
/*
* No locking required for CPU-local interrupts:
*/
if (desc->chip->ack)
desc->chip->ack(irq);
action_ret = handle_IRQ_event(irq, regs, desc->action);
desc->chip->end(irq);
return 1;
}
/*
* If the task is currently running in user mode, don't
* detect soft lockups. If CONFIG_DETECT_SOFTLOCKUP is not
* configured, this should be optimized out.
*/
if (user_mode(regs))
touch_softlockup_watchdog();
spin_lock(&desc->lock);
if (desc->chip->ack)
desc->chip->ack(irq);
/*
* REPLAY is when Linux resends an IRQ that was dropped earlier
* WAITING is used by probe to mark irqs that are being tested
*/
status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING);
status |= IRQ_PENDING; /* we _want_ to handle it */
/*
* If the IRQ is disabled for whatever reason, we cannot
* use the action we have.
*/
action = NULL;
if (likely(!(status & (IRQ_DISABLED | IRQ_INPROGRESS)))) {
action = desc->action;
status &= ~IRQ_PENDING; /* we commit to handling */
status |= IRQ_INPROGRESS; /* we are handling it */
}
desc->status = status;
/*
* If there is no IRQ handler or it was disabled, exit early.
* Since we set PENDING, if another processor is handling
* a different instance of this same irq, the other processor
* will take care of it.
*/
if (unlikely(!action))
goto out;
/*
* hardirq redirection to the irqd process context:
*/
if (redirect_hardirq(desc))
goto out_no_end;
/*
* Edge triggered interrupts need to remember
* pending events.
* This applies to any hw interrupts that allow a second
* instance of the same irq to arrive while we are in do_IRQ
* or in the handler. But the code here only handles the _second_
* instance of the irq, not the third or fourth. So it is mostly
* useful for irq hardware that does not mask cleanly in an
* SMP environment.
*/
for (;;) {
irqreturn_t action_ret;
spin_unlock(&desc->lock);
action_ret = handle_IRQ_event(irq, regs, action);
spin_lock(&desc->lock);
if (!noirqdebug)
note_interrupt(irq, desc, action_ret, regs);
if (likely(!(desc->status & IRQ_PENDING)))
break;
desc->status &= ~IRQ_PENDING;
}
desc->status &= ~IRQ_INPROGRESS;
out:
/*
* The ->end() handler has to deal with interrupts which got
* disabled while the handler was running.
*/
desc->chip->end(irq);
out_no_end:
spin_unlock(&desc->lock);
return 1;
}
