[repost] sched: export sched_set/getaffinity to modules

Commit Message

Sridhar Samudrala July 14, 2010, 11:26 p.m. UTC

None

Patch

diff --git a/include/linux/kthread.h b/include/linux/kthread.h
index aabc8a1..e0616f0 100644
--- a/include/linux/kthread.h
+++ b/include/linux/kthread.h
@@ -9,6 +9,9 @@  struct task_struct *kthread_create(int (*threadfn)(void *data),
 				   const char namefmt[], ...)
 	__attribute__((format(printf, 3, 4)));
 
+struct task_struct *kthread_create_in_current_cg(int (*threadfn)(void *data),
+						 void *data, char *name);
+
 /**
  * kthread_run - create and wake a thread.
  * @threadfn: the function to run until signal_pending(current).
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 83911c7..ea4e737 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -15,6 +15,7 @@ 
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <trace/events/sched.h>
+#include <linux/cgroup.h>
 
 static DEFINE_SPINLOCK(kthread_create_lock);
 static LIST_HEAD(kthread_create_list);
@@ -149,6 +150,42 @@  struct task_struct *kthread_create(int (*threadfn)(void *data),
 }
 EXPORT_SYMBOL(kthread_create);
 
+struct task_struct *kthread_create_in_current_cg(int (*threadfn)(void *data),
+						 void *data, char *name)
+{
+	struct task_struct *worker;
+	cpumask_var_t mask;
+	int ret = -ENOMEM;
+
+	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
+		goto out_free_mask;
+
+	worker = kthread_create(threadfn, data, "%s-%d", name, current->pid);
+	if (IS_ERR(worker))
+		goto out_free_mask;
+
+	ret = sched_getaffinity(current->pid, mask);
+	if (ret)
+		goto out_stop_worker;
+
+	ret = sched_setaffinity(worker->pid, mask);
+	if (ret)
+		goto out_stop_worker;
+
+	ret = cgroup_attach_task_current_cg(worker);
+	if (ret)
+		goto out_stop_worker;
+
+	return worker;
+
+out_stop_worker:
+	kthread_stop(worker);
+out_free_mask:
+	free_cpumask_var(mask);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(kthread_create_in_current_cg);
+
 /**
  * kthread_bind - bind a just-created kthread to a cpu.
  * @p: thread created by kthread_create().