Commit-ID: e8a7035039306c90bcc99129ffc18e0be052bbb9 Gitweb: http://git.kernel.org/tip/e8a7035039306c90bcc99129ffc18e0be052bbb9 Author: Thomas Gleixner <t...@linutronix.de> AuthorDate: Tue, 20 Jun 2017 01:37:27 +0200 Committer: Thomas Gleixner <t...@linutronix.de> CommitDate: Thu, 22 Jun 2017 18:21:16 +0200
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 <t...@linutronix.de> Cc: Jens Axboe <ax...@kernel.dk> Cc: Marc Zyngier <marc.zyng...@arm.com> Cc: Michael Ellerman <m...@ellerman.id.au> Cc: Keith Busch <keith.bu...@intel.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Christoph Hellwig <h...@lst.de> Link: http://lkml.kernel.org/r/20170619235445.354181...@linutronix.de --- kernel/irq/cpuhotplug.c | 36 ++++++++++++++++++++---------------- 1 file changed, 20 insertions(+), 16 deletions(-) diff --git a/kernel/irq/cpuhotplug.c b/kernel/irq/cpuhotplug.c index 9c5521b..41fe1e0 100644 --- a/kernel/irq/cpuhotplug.c +++ b/kernel/irq/cpuhotplug.c @@ -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; } /**
