Commit 787453c2 authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
Browse files

[PATCH] md: complete conversion of md to use kthreads 



There are a few loose ends following the conversion of md to use kthreads:

- Some fields in mdk_thread_t that aren't needed (kthreads does it's own
  completion and manages it's own name).

- thread->run is now never NULL, so no need to check

- Some tests for signal_pending that aren't needed (As we don't use signals
  to stop threads any more)

- Some flush_signals are not needed

- Some waits are interruptible and don't need to be.

Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent fd9d49ca

drivers/md/md.c

+10 −23
Original line number Diff line number Diff line
@@ -3424,11 +3424,9 @@ static int md_thread(void * arg) 
	 */



	allow_signal(SIGKILL);

	complete(thread->event);

	while (!kthread_should_stop()) {

		void (*run)(mddev_t *);



		wait_event_interruptible_timeout(thread->wqueue,

		wait_event_timeout(thread->wqueue,

				   test_bit(THREAD_WAKEUP, &thread->flags)

				   || kthread_should_stop(),

				   thread->timeout);
@@ -3436,9 +3434,7 @@ static int md_thread(void * arg) 


		clear_bit(THREAD_WAKEUP, &thread->flags);



		run = thread->run;

		if (run)

			run(thread->mddev);

		thread->run(thread->mddev);

	}



	return 0;
@@ -3457,7 +3453,6 @@ mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev, 
				 const char *name)

{

	mdk_thread_t *thread;

	struct completion event;



	thread = kmalloc(sizeof(mdk_thread_t), GFP_KERNEL);

	if (!thread)
@@ -3466,18 +3461,14 @@ mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev, 
	memset(thread, 0, sizeof(mdk_thread_t));

	init_waitqueue_head(&thread->wqueue);



	init_completion(&event);

	thread->event = &event;

	thread->run = run;

	thread->mddev = mddev;

	thread->name = name;

	thread->timeout = MAX_SCHEDULE_TIMEOUT;

	thread->tsk = kthread_run(md_thread, thread, name, mdname(thread->mddev));

	if (IS_ERR(thread->tsk)) {

		kfree(thread);

		return NULL;

	}

	wait_for_completion(&event);

	return thread;

}
@@ -3941,9 +3932,7 @@ static void md_do_sync(mddev_t *mddev) 
		mddev->curr_resync = 2;



	try_again:

		if (signal_pending(current) ||

		    kthread_should_stop()) {

			flush_signals(current);

		if (kthread_should_stop()) {

			set_bit(MD_RECOVERY_INTR, &mddev->recovery);

			goto skip;

		}
@@ -3963,9 +3952,8 @@ static void md_do_sync(mddev_t *mddev) 
					 * time 'round when curr_resync == 2

					 */

					continue;

				prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);

				if (!signal_pending(current) &&

				    !kthread_should_stop() &&

				prepare_to_wait(&resync_wait, &wq, TASK_UNINTERRUPTIBLE);

				if (!kthread_should_stop() &&

				    mddev2->curr_resync >= mddev->curr_resync) {

					printk(KERN_INFO "md: delaying resync of %s"

					       " until %s has finished resync (they"
@@ -4074,13 +4062,12 @@ static void md_do_sync(mddev_t *mddev) 
		}





		if (signal_pending(current) || kthread_should_stop()) {

		if (kthread_should_stop()) {

			/*

			 * got a signal, exit.

			 */

			printk(KERN_INFO 

				"md: md_do_sync() got signal ... exiting\n");

			flush_signals(current);

			set_bit(MD_RECOVERY_INTR, &mddev->recovery);

			goto out;

		}
@@ -4102,7 +4089,7 @@ static void md_do_sync(mddev_t *mddev) 
		if (currspeed > sysctl_speed_limit_min) {

			if ((currspeed > sysctl_speed_limit_max) ||

					!is_mddev_idle(mddev)) {

				msleep_interruptible(250);

				msleep(250);

				goto repeat;

			}

		}

include/linux/raid/md_k.h

+0 −2
Original line number Diff line number Diff line
@@ -334,10 +334,8 @@ typedef struct mdk_thread_s { 
	mddev_t			*mddev;

	wait_queue_head_t	wqueue;

	unsigned long           flags;

	struct completion	*event;

	struct task_struct	*tsk;

	unsigned long		timeout;

	const char		*name;

} mdk_thread_t;



#define THREAD_WAKEUP  0

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