cpumask: convert rcutorture.c

We're getting rid of cpumasks on the stack.

Simply change tmp_mask to a global, and allocate it in
rcu_torture_init().

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@freedesktop.org>

diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 7c4142a..9b4a975 100644 (file)
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -126,6 +126,7 @@ static atomic_t n_rcu_torture_mberror;
 static atomic_t n_rcu_torture_error;
 static long n_rcu_torture_timers = 0;
 static struct list_head rcu_torture_removed;
+static cpumask_var_t shuffle_tmp_mask;
 
 static int stutter_pause_test = 0;
 
@@ -889,10 +890,9 @@ static int rcu_idle_cpu;   /* Force all torture tasks off this CPU */
  */
 static void rcu_torture_shuffle_tasks(void)
 {
-       cpumask_t tmp_mask;
        int i;
 
-       cpus_setall(tmp_mask);
+       cpumask_setall(shuffle_tmp_mask);
        get_online_cpus();
 
        /* No point in shuffling if there is only one online CPU (ex: UP) */
@@ -902,29 +902,29 @@ static void rcu_torture_shuffle_tasks(void)
        }
 
        if (rcu_idle_cpu != -1)
-               cpu_clear(rcu_idle_cpu, tmp_mask);
+               cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask);
 
-       set_cpus_allowed_ptr(current, &tmp_mask);
+       set_cpus_allowed_ptr(current, shuffle_tmp_mask);
 
        if (reader_tasks) {
                for (i = 0; i < nrealreaders; i++)
                        if (reader_tasks[i])
                                set_cpus_allowed_ptr(reader_tasks[i],
-                                                    &tmp_mask);
+                                                    shuffle_tmp_mask);
        }
 
        if (fakewriter_tasks) {
                for (i = 0; i < nfakewriters; i++)
                        if (fakewriter_tasks[i])
                                set_cpus_allowed_ptr(fakewriter_tasks[i],
-                                                    &tmp_mask);
+                                                    shuffle_tmp_mask);
        }
 
        if (writer_task)
-               set_cpus_allowed_ptr(writer_task, &tmp_mask);
+               set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask);
 
        if (stats_task)
-               set_cpus_allowed_ptr(stats_task, &tmp_mask);
+               set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask);
 
        if (rcu_idle_cpu == -1)
                rcu_idle_cpu = num_online_cpus() - 1;
@@ -1012,6 +1012,7 @@ rcu_torture_cleanup(void)
        if (shuffler_task) {
                VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task");
                kthread_stop(shuffler_task);
+               free_cpumask_var(shuffle_tmp_mask);
        }
        shuffler_task = NULL;
 
@@ -1190,10 +1191,18 @@ rcu_torture_init(void)
        }
        if (test_no_idle_hz) {
                rcu_idle_cpu = num_online_cpus() - 1;
+
+               if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
+                       firsterr = -ENOMEM;
+                       VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask");
+                       goto unwind;
+               }
+
                /* Create the shuffler thread */
                shuffler_task = kthread_run(rcu_torture_shuffle, NULL,
                                          "rcu_torture_shuffle");
                if (IS_ERR(shuffler_task)) {
+                       free_cpumask_var(shuffle_tmp_mask);
                        firsterr = PTR_ERR(shuffler_task);
                        VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler");
                        shuffler_task = NULL;