eliminate direct assignments of CPU masks

Use cpumask_copy() instead of direct variable assignments for copying
CPU masks. While direct assignments are not a problem when both sides
are variables actually defined as cpumask_t (except for possibly
copying *much* more than would actually need to be copied), they must
not happen when the original variable is of type cpumask_var_t (which
may have lass space allocated to it than a full cpumask_t). Eliminate
as many of such assignments as possible (in several cases it's even
possible to collapse two operations [copy then clear one bit] into one
[cpumask_andnot()]), and thus set the way for reducing the allocation
size in alloc_cpumask_var().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>

1 files changed, 7 insertions, 7 deletions

diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c
index 4a93f29d76..40326f2bfe 100644
--- a/xen/arch/x86/irq.c
+++ b/xen/arch/x86/irq.c
@@ -1040,7 +1040,7 @@ static void irq_guest_eoi_timer_fn(void *data)
             desc->handler->end(desc, 0);
         break;
     case ACKTYPE_EOI:
-        cpu_eoi_map = action->cpu_eoi_map;
+        cpumask_copy(&cpu_eoi_map, &action->cpu_eoi_map);
         spin_unlock_irq(&desc->lock);
         on_selected_cpus(&cpu_eoi_map, set_eoi_ready, desc, 0);
         spin_lock_irq(&desc->lock);
@@ -1366,9 +1366,9 @@ void desc_guest_eoi(struct irq_desc *desc, struct pirq *pirq)
 
     ASSERT(action->ack_type == ACKTYPE_EOI);
         
-    cpu_eoi_map = action->cpu_eoi_map;
+    cpumask_copy(&cpu_eoi_map, &action->cpu_eoi_map);
 
-    if ( cpu_test_and_clear(smp_processor_id(), cpu_eoi_map) )
+    if ( cpumask_test_and_clear_cpu(smp_processor_id(), &cpu_eoi_map) )
     {
         __set_eoi_ready(desc);
         spin_unlock(&desc->lock);
@@ -1380,7 +1380,7 @@ void desc_guest_eoi(struct irq_desc *desc, struct pirq *pirq)
         spin_unlock_irq(&desc->lock);
     }
 
-    if ( !cpus_empty(cpu_eoi_map) )
+    if ( !cpumask_empty(&cpu_eoi_map) )
         on_selected_cpus(&cpu_eoi_map, set_eoi_ready, desc, 0);
 }
 
@@ -1619,7 +1619,7 @@ static irq_guest_action_t *__pirq_guest_unbind(
              (--action->in_flight == 0) &&
              (action->nr_guests != 0) )
         {
-            cpu_eoi_map = action->cpu_eoi_map;
+            cpumask_copy(&cpu_eoi_map, &action->cpu_eoi_map);
             spin_unlock_irq(&desc->lock);
             on_selected_cpus(&cpu_eoi_map, set_eoi_ready, desc, 0);
             spin_lock_irq(&desc->lock);
@@ -1649,8 +1649,8 @@ static irq_guest_action_t *__pirq_guest_unbind(
      * would need to flush all ready EOIs before returning as otherwise the
      * desc->handler could change and we would call the wrong 'end' hook.
      */
-    cpu_eoi_map = action->cpu_eoi_map;
-    if ( !cpus_empty(cpu_eoi_map) )
+    cpumask_copy(&cpu_eoi_map, &action->cpu_eoi_map);
+    if ( !cpumask_empty(&cpu_eoi_map) )
     {
         BUG_ON(action->ack_type != ACKTYPE_EOI);
         spin_unlock_irq(&desc->lock);