x86/irq: Reorganize the return path in assign_irq_vector
Use an explicit goto for the cases where we have success in the search/update
and return -ENOSPC if the search loop ends due to no space.
Preparatory patch for fixes. No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Borislav Petkov <bp@alien8.de>
Tested-by: Joe Lawrence <joe.lawrence@stratus.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jeremiah Mahler <jmmahler@gmail.com>
Cc: andy.shevchenko@gmail.com
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: stable@vger.kernel.org #4.3+
Link: http://lkml.kernel.org/r/20151231160106.403491024@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index 19082cf..613b1cd 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -118,13 +118,12 @@
*/
static int current_vector = FIRST_EXTERNAL_VECTOR + VECTOR_OFFSET_START;
static int current_offset = VECTOR_OFFSET_START % 16;
- int cpu, err;
+ int cpu;
if (d->move_in_progress)
return -EBUSY;
/* Only try and allocate irqs on cpus that are present */
- err = -ENOSPC;
cpumask_clear(d->old_domain);
cpumask_clear(searched_cpumask);
cpu = cpumask_first_and(mask, cpu_online_mask);
@@ -134,9 +133,8 @@
apic->vector_allocation_domain(cpu, vector_cpumask, mask);
if (cpumask_subset(vector_cpumask, d->domain)) {
- err = 0;
if (cpumask_equal(vector_cpumask, d->domain))
- break;
+ goto success;
/*
* New cpumask using the vector is a proper subset of
* the current in use mask. So cleanup the vector
@@ -147,7 +145,7 @@
d->move_in_progress =
cpumask_intersects(d->old_domain, cpu_online_mask);
cpumask_and(d->domain, d->domain, vector_cpumask);
- break;
+ goto success;
}
vector = current_vector;
@@ -187,17 +185,13 @@
per_cpu(vector_irq, new_cpu)[vector] = irq_to_desc(irq);
d->cfg.vector = vector;
cpumask_copy(d->domain, vector_cpumask);
- err = 0;
- break;
+ goto success;
}
+ return -ENOSPC;
- if (!err) {
- /* cache destination APIC IDs into cfg->dest_apicid */
- err = apic->cpu_mask_to_apicid_and(mask, d->domain,
- &d->cfg.dest_apicid);
- }
-
- return err;
+success:
+ /* cache destination APIC IDs into cfg->dest_apicid */
+ return apic->cpu_mask_to_apicid_and(mask, d->domain, &d->cfg.dest_apicid);
}
static int assign_irq_vector(int irq, struct apic_chip_data *data,