genirq/cpuhotplug: Reorder check logic

Move the checks for a valid irq chip and the irq_set_affinity() callback
right in front of the whole migration logic. No point in doing a gazillion
of other things when the interrupt cannot be migrated at all.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20170619235445.354181630@linutronix.de
This commit is contained in:
Thomas Gleixner 2017-06-20 01:37:27 +02:00
parent 735c09524d
commit e8a7035039

View File

@ -17,9 +17,20 @@
static bool migrate_one_irq(struct irq_desc *desc)
{
struct irq_data *d = irq_desc_get_irq_data(desc);
struct irq_chip *chip = irq_data_get_irq_chip(d);
const struct cpumask *affinity = d->common->affinity;
struct irq_chip *c;
bool ret = false;
bool brokeaff = false;
int err;
/*
* IRQ chip might be already torn down, but the irq descriptor is
* still in the radix tree. Also if the chip has no affinity setter,
* nothing can be done here.
*/
if (!chip || !chip->irq_set_affinity) {
pr_debug("IRQ %u: Unable to migrate away\n", d->irq);
return false;
}
/*
* If this is a per-CPU interrupt, or the affinity does not
@ -31,23 +42,16 @@ static bool migrate_one_irq(struct irq_desc *desc)
if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
affinity = cpu_online_mask;
ret = true;
brokeaff = true;
}
c = irq_data_get_irq_chip(d);
if (!c->irq_set_affinity) {
pr_debug("IRQ%u: unable to set affinity\n", d->irq);
ret = false;
} else {
int r = irq_do_set_affinity(d, affinity, false);
if (r) {
pr_warn_ratelimited("IRQ%u: set affinity failed(%d).\n",
d->irq, r);
ret = false;
}
err = irq_do_set_affinity(d, affinity, false);
if (err) {
pr_warn_ratelimited("IRQ%u: set affinity failed(%d).\n",
d->irq, err);
return false;
}
return ret;
return brokeaff;
}
/**