kthread: Do not use TIMER_IRQSAFE

The TIMER_IRQSAFE usage was introduced in commit 22597dc3d97b1 ("kthread:
initial support for delayed kthread work") which modelled the delayed
kthread code after workqueue's code. The workqueue code requires the flag
TIMER_IRQSAFE for synchronisation purpose. This is not true for kthread's
delay timer since all operations occur under a lock.

Remove TIMER_IRQSAFE from the timer initialisation and use timer_setup()
for initialisation purpose which is the official function.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lkml.kernel.org/r/20190212162554.19779-2-bigeasy@linutronix.de

diff --git a/include/linux/kthread.h b/include/linux/kthread.h
index 6b8c064..3d9d834 100644 (file)
--- a/include/linux/kthread.h
+++ b/include/linux/kthread.h
@@ -164,9 +164,8 @@ extern void __kthread_init_worker(struct kthread_worker *worker,
 #define kthread_init_delayed_work(dwork, fn)                           \
        do {                                                            \
                kthread_init_work(&(dwork)->work, (fn));                \
-               __init_timer(&(dwork)->timer,                           \
-                            kthread_delayed_work_timer_fn,             \
-                            TIMER_IRQSAFE);                            \
+               timer_setup(&(dwork)->timer,                            \
+                            kthread_delayed_work_timer_fn, 0);         \
        } while (0)
 
 int kthread_worker_fn(void *worker_ptr);

diff --git a/kernel/kthread.c b/kernel/kthread.c
index 5641b55..5373355 100644 (file)
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -835,6 +835,7 @@ void kthread_delayed_work_timer_fn(struct timer_list *t)
        struct kthread_delayed_work *dwork = from_timer(dwork, t, timer);
        struct kthread_work *work = &dwork->work;
        struct kthread_worker *worker = work->worker;
+       unsigned long flags;
 
        /*
         * This might happen when a pending work is reinitialized.
@@ -843,7 +844,7 @@ void kthread_delayed_work_timer_fn(struct timer_list *t)
        if (WARN_ON_ONCE(!worker))
                return;
 
-       raw_spin_lock(&worker->lock);
+       raw_spin_lock_irqsave(&worker->lock, flags);
        /* Work must not be used with >1 worker, see kthread_queue_work(). */
        WARN_ON_ONCE(work->worker != worker);
 
@@ -852,7 +853,7 @@ void kthread_delayed_work_timer_fn(struct timer_list *t)
        list_del_init(&work->node);
        kthread_insert_work(worker, work, &worker->work_list);
 
-       raw_spin_unlock(&worker->lock);
+       raw_spin_unlock_irqrestore(&worker->lock, flags);
 }
 EXPORT_SYMBOL(kthread_delayed_work_timer_fn);