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, 3 insertions, 3 deletions

diff --git a/xen/common/stop_machine.c b/xen/common/stop_machine.c
index 9bf271452d..eb38da58f8 100644
--- a/xen/common/stop_machine.c
+++ b/xen/common/stop_machine.c
@@ -81,9 +81,9 @@ int stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu)
     if ( !get_cpu_maps() )
         return -EBUSY;
 
-    allbutself = cpu_online_map;
-    cpu_clear(smp_processor_id(), allbutself);
-    nr_cpus = cpus_weight(allbutself);
+    cpumask_andnot(&allbutself, &cpu_online_map,
+                   cpumask_of(smp_processor_id()));
+    nr_cpus = cpumask_weight(&allbutself);
 
     /* Must not spin here as the holder will expect us to be descheduled. */
     if ( !spin_trylock(&stopmachine_lock) )