#include <linux/unistd.h>
#include <linux/file.h>
#include <linux/module.h>
-#include <linux/mutex.h>
#include <asm/semaphore.h>
/*
/* Thread stopping is done by setthing this var: lock serializes
* multiple kthread_stop calls. */
-static DEFINE_MUTEX(kthread_stop_lock);
+static DECLARE_MUTEX(kthread_stop_lock);
static struct kthread_stop_info kthread_stop_info;
-/**
- * kthread_should_stop - should this kthread return now?
- *
- * When someone calls kthread_stop on your kthread, it will be woken
- * and this will return true. You should then return, and your return
- * value will be passed through to kthread_stop().
- */
int kthread_should_stop(void)
{
return (kthread_stop_info.k == current);
create->result = ERR_PTR(pid);
} else {
wait_for_completion(&create->started);
- read_lock(&tasklist_lock);
create->result = find_task_by_real_pid(pid);
- read_unlock(&tasklist_lock);
}
complete(&create->done);
}
-/**
- * kthread_create - create a kthread.
- * @threadfn: the function to run until signal_pending(current).
- * @data: data ptr for @threadfn.
- * @namefmt: printf-style name for the thread.
- *
- * Description: This helper function creates and names a kernel
- * thread. The thread will be stopped: use wake_up_process() to start
- * it. See also kthread_run(), kthread_create_on_cpu().
- *
- * When woken, the thread will run @threadfn() with @data as its
- * argument. @threadfn can either call do_exit() directly if it is a
- * standalone thread for which noone will call kthread_stop(), or
- * return when 'kthread_should_stop()' is true (which means
- * kthread_stop() has been called). The return value should be zero
- * or a negative error number; it will be passed to kthread_stop().
- *
- * Returns a task_struct or ERR_PTR(-ENOMEM).
- */
struct task_struct *kthread_create(int (*threadfn)(void *data),
void *data,
const char namefmt[],
}
EXPORT_SYMBOL(kthread_create);
-/**
- * kthread_bind - bind a just-created kthread to a cpu.
- * @k: thread created by kthread_create().
- * @cpu: cpu (might not be online, must be possible) for @k to run on.
- *
- * Description: This function is equivalent to set_cpus_allowed(),
- * except that @cpu doesn't need to be online, and the thread must be
- * stopped (i.e., just returned from kthread_create().
- */
void kthread_bind(struct task_struct *k, unsigned int cpu)
{
BUG_ON(k->state != TASK_INTERRUPTIBLE);
}
EXPORT_SYMBOL(kthread_bind);
-/**
- * kthread_stop - stop a thread created by kthread_create().
- * @k: thread created by kthread_create().
- *
- * Sets kthread_should_stop() for @k to return true, wakes it, and
- * waits for it to exit. Your threadfn() must not call do_exit()
- * itself if you use this function! This can also be called after
- * kthread_create() instead of calling wake_up_process(): the thread
- * will exit without calling threadfn().
- *
- * Returns the result of threadfn(), or %-EINTR if wake_up_process()
- * was never called.
- */
int kthread_stop(struct task_struct *k)
+{
+ return kthread_stop_sem(k, NULL);
+}
+EXPORT_SYMBOL(kthread_stop);
+
+int kthread_stop_sem(struct task_struct *k, struct semaphore *s)
{
int ret;
- mutex_lock(&kthread_stop_lock);
+ down(&kthread_stop_lock);
/* It could exit after stop_info.k set, but before wake_up_process. */
get_task_struct(k);
/* Now set kthread_should_stop() to true, and wake it up. */
kthread_stop_info.k = k;
- wake_up_process(k);
+ if (s)
+ up(s);
+ else
+ wake_up_process(k);
put_task_struct(k);
/* Once it dies, reset stop ptr, gather result and we're done. */
wait_for_completion(&kthread_stop_info.done);
kthread_stop_info.k = NULL;
ret = kthread_stop_info.err;
- mutex_unlock(&kthread_stop_lock);
+ up(&kthread_stop_lock);
return ret;
}
-EXPORT_SYMBOL(kthread_stop);
+EXPORT_SYMBOL(kthread_stop_sem);
static __init int helper_init(void)
{
return 0;
}
-
core_initcall(helper_init);
+
git://git.onelab.eu / linux-2.6.git / blobdiff