.user_mask = NULL,
.flags = SCA_USER, /* clear the user requested mask */
};
+ union cpumask_rcuhead {
+ cpumask_t cpumask;
+ struct rcu_head rcu;
+ };
__do_set_cpus_allowed(p, &ac);
- kfree(ac.user_mask);
+
+ /*
+ * Because this is called with p->pi_lock held, it is not possible
+ * to use kfree() here (when PREEMPT_RT=y), therefore punt to using
+ * kfree_rcu().
+ */
+ kfree_rcu((union cpumask_rcuhead *)ac.user_mask, rcu);
+}
+
+static cpumask_t *alloc_user_cpus_ptr(int node)
+{
+ /*
+ * See do_set_cpus_allowed() above for the rcu_head usage.
+ */
+ int size = max_t(int, cpumask_size(), sizeof(struct rcu_head));
+
+ return kmalloc_node(size, GFP_KERNEL, node);
}
int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src,
if (data_race(!src->user_cpus_ptr))
return 0;
- user_mask = kmalloc_node(cpumask_size(), GFP_KERNEL, node);
+ user_mask = alloc_user_cpus_ptr(node);
if (!user_mask)
return -ENOMEM;
return false;
}
+static inline cpumask_t *alloc_user_cpus_ptr(int node)
+{
+ return NULL;
+}
+
#endif /* !CONFIG_SMP */
static void
if (retval)
goto out_put_task;
- user_mask = kmalloc(cpumask_size(), GFP_KERNEL);
- if (!user_mask) {
+ user_mask = alloc_user_cpus_ptr(NUMA_NO_NODE);
+ if (IS_ENABLED(CONFIG_SMP) && !user_mask) {
retval = -ENOMEM;
goto out_put_task;
}