cpumask: update irq_desc to use cpumask_var_t

Impact: reduce memory usage, use new cpumask API.

Replace the affinity and pending_masks with cpumask_var_t's.  This adds
to the significant size reduction done with the SPARSE_IRQS changes.

The added functions (init_alloc_desc_masks & init_copy_desc_masks) are
in the include file so they can be inlined (and optimized out for the
!CONFIG_CPUMASKS_OFFSTACK case.)  [Naming chosen to be consistent with
the other init*irq functions, as well as the backwards arg declaration
of "from, to" instead of the more common "to, from" standard.]

Includes a slight change to the declaration of struct irq_desc to embed
the pending_mask within ifdef(CONFIG_SMP) to be consistent with other
references, and some small changes to Xen.

Tested: sparse/non-sparse/cpumask_offstack/non-cpumask_offstack/nonuma/nosmp on x86_64

Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: virtualization@lists.osdl.org
Cc: xen-devel@lists.xensource.com
Cc: Yinghai Lu <yhlu.kernel@gmail.com>

1 files changed, 6 insertions, 6 deletions

diff --git a/kernel/irq/migration.c b/kernel/irq/migration.c
index bd72329e630c..e05ad9be43b7 100644
--- a/kernel/irq/migration.c
+++ b/kernel/irq/migration.c
@@ -18,7 +18,7 @@ void move_masked_irq(int irq)
 
         desc->status &= ~IRQ_MOVE_PENDING;
 
-        if (unlikely(cpumask_empty(&desc->pending_mask)))
+        if (unlikely(cpumask_empty(desc->pending_mask)))
                 return;
 
         if (!desc->chip->set_affinity)
@@ -38,13 +38,13 @@ void move_masked_irq(int irq)
          * For correct operation this depends on the caller
          * masking the irqs.
          */
-        if (likely(cpumask_any_and(&desc->pending_mask, cpu_online_mask)
+        if (likely(cpumask_any_and(desc->pending_mask, cpu_online_mask)
                    < nr_cpu_ids)) {
-                cpumask_and(&desc->affinity,
-                            &desc->pending_mask, cpu_online_mask);
-                desc->chip->set_affinity(irq, &desc->affinity);
+                cpumask_and(desc->affinity,
+                            desc->pending_mask, cpu_online_mask);
+                desc->chip->set_affinity(irq, desc->affinity);
         }
-        cpumask_clear(&desc->pending_mask);
+        cpumask_clear(desc->pending_mask);
 }
 
 void move_native_irq(int irq)