x86/irq: Copy vectormask instead of an AND operation

commit 9ac15b7a8af4cf3337a101498c0ed690d23ade75 upstream.

In the case that the new vector mask is a subset of the existing mask there is
no point to do a AND operation of currentmask & newmask. The result is
newmask. So we can simply copy the new mask to the current mask and be done
with it. Preparatory patch for further consolidation.

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>
Link: http://lkml.kernel.org/r/20151231160106.640253454@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index d96b43c02ba7d6586c3461b39b3f65aab3a88994..641d592f524af6dc70a093485c5658d578d579f1 100644 (file)
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -154,7 +154,7 @@ static int __assign_irq_vector(int irq, struct apic_chip_data *d,
                                       vector_cpumask);
                        d->move_in_progress =
                           cpumask_intersects(d->old_domain, cpu_online_mask);
-                       cpumask_and(d->domain, d->domain, vector_cpumask);
+                       cpumask_copy(d->domain, vector_cpumask);
                        goto success;
                }