srcu: Use IRQ_WORK_INIT_HARD for srcu's irq_work

The irq_work in srcu is used to schedule a delayed work. The work item
is not scheduled directly because it is not always possible wake a
thread directly.

On PREEMPT_RT the default irq_work is initialized with IRQ_WORK_LAZY and
is delayed to the irq_work thread. A system booted with the command line
"trace_event=…" will freeze during boot because the irq_work thread is
not yet deployed (and tracing uses synchronize_srcu() in
tp_rcu_cond_sync()).

The irq_work performs just a wakeup a thread, there is nothing wrong
with doing this from hardirq context on PREEMPT_RT.

Use IRQ_WORK_INIT_HARD for srcu's irq_work.

Fixes: 7c405fb3279b3 ("rcu: Use an intermediate irq_work to start process_srcu()")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

0 files changed, 0 insertions, 0 deletions