kthread: implement kthread_data()

Implement kthread_data() which takes @task pointing to a kthread and
returns @data specified when creating the kthread.  The caller is
responsible for ensuring the validity of @task when calling this
function.

Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Tejun Heo 2010-06-29 10:07:09 +02:00
parent 7bc465605f
commit 82805ab77d
2 changed files with 16 additions and 0 deletions

View File

@ -30,6 +30,7 @@ struct task_struct *kthread_create(int (*threadfn)(void *data),
void kthread_bind(struct task_struct *k, unsigned int cpu);
int kthread_stop(struct task_struct *k);
int kthread_should_stop(void);
void *kthread_data(struct task_struct *k);
int kthreadd(void *unused);
extern struct task_struct *kthreadd_task;

View File

@ -37,6 +37,7 @@ struct kthread_create_info
struct kthread {
int should_stop;
void *data;
struct completion exited;
};
@ -56,6 +57,19 @@ int kthread_should_stop(void)
}
EXPORT_SYMBOL(kthread_should_stop);
/**
* kthread_data - return data value specified on kthread creation
* @task: kthread task in question
*
* Return the data value specified when kthread @task was created.
* The caller is responsible for ensuring the validity of @task when
* calling this function.
*/
void *kthread_data(struct task_struct *task)
{
return to_kthread(task)->data;
}
static int kthread(void *_create)
{
/* Copy data: it's on kthread's stack */
@ -66,6 +80,7 @@ static int kthread(void *_create)
int ret;
self.should_stop = 0;
self.data = data;
init_completion(&self.exited);
current->vfork_done = &self.exited;