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, 2 insertions, 2 deletions

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index eb0dfdeaa949..e0767ff35d6c 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -125,7 +125,7 @@ static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
 
         BUG_ON(irq == -1);
 #ifdef CONFIG_SMP
-        irq_to_desc(irq)->affinity = cpumask_of_cpu(cpu);
+        cpumask_copy(irq_to_desc(irq)->affinity, cpumask_of(cpu));
 #endif
 
         __clear_bit(chn, cpu_evtchn_mask[cpu_evtchn[chn]]);
@@ -142,7 +142,7 @@ static void init_evtchn_cpu_bindings(void)
 
         /* By default all event channels notify CPU#0. */
         for_each_irq_desc(i, desc) {
-                desc->affinity = cpumask_of_cpu(0);
+                cpumask_copy(desc->affinity, cpumask_of(0));
         }
 #endif