diff options
| author | Ivo Sieben <meltedpianoman@gmail.com> | 2013-06-03 14:12:02 +0400 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2013-06-11 18:18:50 +0400 |
| commit | ee23871389d51e07380d23887333622fbe7d3dd9 (patch) | |
| tree | 729b38096a39a2e9ff318149c40a6ca53199707e | |
| parent | 9dbd90f17e4f380593ec5194c2a4d5e52c5f72d1 (diff) | |
| download | linux-ee23871389d51e07380d23887333622fbe7d3dd9.tar.xz | |
genirq: Set irq thread to RT priority on creation
When a threaded irq handler is installed the irq thread is initially
created on normal scheduling priority. Only after the irq thread is
woken up it sets its priority to RT_FIFO MAX_USER_RT_PRIO/2 itself.
This means that interrupts that occur directly after the irq handler
is installed will be handled on a normal scheduling priority instead
of the realtime priority that one would expect.
Fix this by setting the RT priority on creation of the irq_thread.
Signed-off-by: Ivo Sieben <meltedpianoman@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1370254322-17240-1-git-send-email-meltedpianoman@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | kernel/irq/manage.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index fa17855ca65a..e16caa81f887 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -840,9 +840,6 @@ static void irq_thread_dtor(struct callback_head *unused) static int irq_thread(void *data) { struct callback_head on_exit_work; - static const struct sched_param param = { - .sched_priority = MAX_USER_RT_PRIO/2, - }; struct irqaction *action = data; struct irq_desc *desc = irq_to_desc(action->irq); irqreturn_t (*handler_fn)(struct irq_desc *desc, @@ -854,8 +851,6 @@ static int irq_thread(void *data) else handler_fn = irq_thread_fn; - sched_setscheduler(current, SCHED_FIFO, ¶m); - init_task_work(&on_exit_work, irq_thread_dtor); task_work_add(current, &on_exit_work, false); @@ -950,6 +945,9 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) */ if (new->thread_fn && !nested) { struct task_struct *t; + static const struct sched_param param = { + .sched_priority = MAX_USER_RT_PRIO/2, + }; t = kthread_create(irq_thread, new, "irq/%d-%s", irq, new->name); @@ -957,6 +955,9 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) ret = PTR_ERR(t); goto out_mput; } + + sched_setscheduler(t, SCHED_FIFO, ¶m); + /* * We keep the reference to the task struct even if * the thread dies to avoid that the interrupt code |