sched: convert sched_domain_debug to cpumask_var_t.

Impact: stack usage reduction

Dynamically allocating cpumasks (when CONFIG_CPUMASK_OFFSTACK) saves
stack space.  cpumask_var_t is just a struct cpumask for
!CONFIG_CPUMASK_OFFSTACK.

In this case, we always alloced, but we don't need to any more.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/kernel/sched.c b/kernel/sched.c
index 2d4ff91e0c97a5f55a23eef7c84ec52a3371482f..24012c2a889273b4e15099b32f9be3e43a2fcd8c 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -6706,7 +6706,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
 
 static void sched_domain_debug(struct sched_domain *sd, int cpu)
 {
-       cpumask_t *groupmask;
+       cpumask_var_t groupmask;
        int level = 0;
 
        if (!sd) {
@@ -6716,8 +6716,7 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu)
 
        printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu);
 
-       groupmask = kmalloc(sizeof(cpumask_t), GFP_KERNEL);
-       if (!groupmask) {
+       if (!alloc_cpumask_var(&groupmask, GFP_KERNEL)) {
                printk(KERN_DEBUG "Cannot load-balance (out of memory)\n");
                return;
        }
@@ -6730,7 +6729,7 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu)
                if (!sd)
                        break;
        }
-       kfree(groupmask);
+       free_cpumask_var(groupmask);
 }
 #else /* !CONFIG_SCHED_DEBUG */
 # define sched_domain_debug(sd, cpu) do { } while (0)