Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Ingo Molnar:
 "Affinity fixes and a nested threaded IRQ handling fix."

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Always force thread affinity
  irq: Set CPU affinity right on thread creation
  genirq: Provide means to retrigger parent
This commit is contained in:
Linus Torvalds 2012-12-11 18:12:06 -08:00
commit aefb058b0c
5 changed files with 60 additions and 2 deletions

View File

@ -392,6 +392,15 @@ static inline void irq_move_masked_irq(struct irq_data *data) { }
extern int no_irq_affinity;
#ifdef CONFIG_HARDIRQS_SW_RESEND
int irq_set_parent(int irq, int parent_irq);
#else
static inline int irq_set_parent(int irq, int parent_irq)
{
return 0;
}
#endif
/*
* Built-in IRQ handlers for various IRQ types,
* callable via desc->handle_irq()

View File

@ -11,6 +11,8 @@
struct irq_affinity_notify;
struct proc_dir_entry;
struct module;
struct irq_desc;
/**
* struct irq_desc - interrupt descriptor
* @irq_data: per irq and chip data passed down to chip functions
@ -65,6 +67,7 @@ struct irq_desc {
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *dir;
#endif
int parent_irq;
struct module *owner;
const char *name;
} ____cacheline_internodealigned_in_smp;

View File

@ -272,6 +272,7 @@ void handle_nested_irq(unsigned int irq)
raw_spin_lock_irq(&desc->lock);
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
kstat_incr_irqs_this_cpu(irq, desc);
action = desc->action;

View File

@ -616,6 +616,22 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
return ret;
}
#ifdef CONFIG_HARDIRQS_SW_RESEND
int irq_set_parent(int irq, int parent_irq)
{
unsigned long flags;
struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
if (!desc)
return -EINVAL;
desc->parent_irq = parent_irq;
irq_put_desc_unlock(desc, flags);
return 0;
}
#endif
/*
* Default primary interrupt handler for threaded interrupts. Is
* assigned as primary handler when request_threaded_irq is called
@ -716,6 +732,7 @@ static void
irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
{
cpumask_var_t mask;
bool valid = true;
if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
return;
@ -730,10 +747,18 @@ irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
}
raw_spin_lock_irq(&desc->lock);
cpumask_copy(mask, desc->irq_data.affinity);
/*
* This code is triggered unconditionally. Check the affinity
* mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
*/
if (desc->irq_data.affinity)
cpumask_copy(mask, desc->irq_data.affinity);
else
valid = false;
raw_spin_unlock_irq(&desc->lock);
set_cpus_allowed_ptr(current, mask);
if (valid)
set_cpus_allowed_ptr(current, mask);
free_cpumask_var(mask);
}
#else
@ -833,6 +858,8 @@ static int irq_thread(void *data)
init_task_work(&on_exit_work, irq_thread_dtor);
task_work_add(current, &on_exit_work, false);
irq_thread_check_affinity(desc, action);
while (!irq_wait_for_interrupt(action)) {
irqreturn_t action_ret;
@ -936,6 +963,16 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
*/
get_task_struct(t);
new->thread = t;
/*
* Tell the thread to set its affinity. This is
* important for shared interrupt handlers as we do
* not invoke setup_affinity() for the secondary
* handlers as everything is already set up. Even for
* interrupts marked with IRQF_NO_BALANCE this is
* correct as we want the thread to move to the cpu(s)
* on which the requesting code placed the interrupt.
*/
set_bit(IRQTF_AFFINITY, &new->thread_flags);
}
if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {

View File

@ -74,6 +74,14 @@ void check_irq_resend(struct irq_desc *desc, unsigned int irq)
if (!desc->irq_data.chip->irq_retrigger ||
!desc->irq_data.chip->irq_retrigger(&desc->irq_data)) {
#ifdef CONFIG_HARDIRQS_SW_RESEND
/*
* If the interrupt has a parent irq and runs
* in the thread context of the parent irq,
* retrigger the parent.
*/
if (desc->parent_irq &&
irq_settings_is_nested_thread(desc))
irq = desc->parent_irq;
/* Set it pending and activate the softirq: */
set_bit(irq, irqs_resend);
tasklet_schedule(&resend_tasklet);