[PATCH] md: use kthread infrastructure in md
Switch MD to use the kthread infrastructure, to simplify the code and get rid
of tasklist_lock abuse in md_unregister_thread.
Also don't flush signals in md_thread, as the called thread will always do
that.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 008149e..30e3624 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -34,6 +34,7 @@
#include <linux/module.h>
#include <linux/config.h>
+#include <linux/kthread.h>
#include <linux/linkage.h>
#include <linux/raid/md.h>
#include <linux/raid/bitmap.h>
@@ -3049,18 +3050,6 @@
{
mdk_thread_t *thread = arg;
- lock_kernel();
-
- /*
- * Detach thread
- */
-
- daemonize(thread->name, mdname(thread->mddev));
-
- current->exit_signal = SIGCHLD;
- allow_signal(SIGKILL);
- thread->tsk = current;
-
/*
* md_thread is a 'system-thread', it's priority should be very
* high. We avoid resource deadlocks individually in each
@@ -3072,14 +3061,14 @@
* bdflush, otherwise bdflush will deadlock if there are too
* many dirty RAID5 blocks.
*/
- unlock_kernel();
complete(thread->event);
- while (thread->run) {
+ while (!kthread_should_stop()) {
void (*run)(mddev_t *);
wait_event_interruptible_timeout(thread->wqueue,
- test_bit(THREAD_WAKEUP, &thread->flags),
+ test_bit(THREAD_WAKEUP, &thread->flags)
+ || kthread_should_stop(),
thread->timeout);
try_to_freeze();
@@ -3088,11 +3077,8 @@
run = thread->run;
if (run)
run(thread->mddev);
-
- if (signal_pending(current))
- flush_signals(current);
}
- complete(thread->event);
+
return 0;
}
@@ -3109,11 +3095,9 @@
const char *name)
{
mdk_thread_t *thread;
- int ret;
struct completion event;
- thread = (mdk_thread_t *) kmalloc
- (sizeof(mdk_thread_t), GFP_KERNEL);
+ thread = kmalloc(sizeof(mdk_thread_t), GFP_KERNEL);
if (!thread)
return NULL;
@@ -3126,8 +3110,8 @@
thread->mddev = mddev;
thread->name = name;
thread->timeout = MAX_SCHEDULE_TIMEOUT;
- ret = kernel_thread(md_thread, thread, 0);
- if (ret < 0) {
+ thread->tsk = kthread_run(md_thread, thread, mdname(thread->mddev));
+ if (IS_ERR(thread->tsk)) {
kfree(thread);
return NULL;
}
@@ -3137,21 +3121,9 @@
void md_unregister_thread(mdk_thread_t *thread)
{
- struct completion event;
-
- init_completion(&event);
-
- thread->event = &event;
-
- /* As soon as ->run is set to NULL, the task could disappear,
- * so we need to hold tasklist_lock until we have sent the signal
- */
dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
- read_lock(&tasklist_lock);
- thread->run = NULL;
- send_sig(SIGKILL, thread->tsk, 1);
- read_unlock(&tasklist_lock);
- wait_for_completion(&event);
+
+ kthread_stop(thread->tsk);
kfree(thread);
}