rcu/tree: Skip entry into the page allocator for PREEMPT_RT
To keep kfree_rcu() path working on raw non-preemptible sections,
prevent the optional entry into the allocator as it uses sleeping locks.
In fact, even if the caller of kfree_rcu() is preemptible, this path
still is not, as krcp->lock is a raw spinlock as done in previous
patches. With additional page pre-allocation in the works, hitting this
return is going to be much less likely soon so just prevent it for now
so that PREEMPT_RT does not break. Note that page allocation here is an
optimization and skipping it still makes kfree_rcu() work.
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Uladzislau Rezki <urezki@gmail.com>
Co-developed-by: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
1 file changed
