[PATCH] completion: Use lockdep_assert_RT_in_threaded_ctx() in complete_all()
From: Sebastian Siewior <bigeasy@linutronix.de>
Date: 2020-03-23 15:20:51
Also in:
linux-acpi, linux-pci, linux-pm, linux-usb, linux-wireless, lkml, netdev, platform-driver-x86
Subsystem:
locking primitives, scheduler, the rest · Maintainers:
Peter Zijlstra, Ingo Molnar, Will Deacon, Boqun Feng, Juri Lelli, Vincent Guittot, Linus Torvalds
The warning was intended to spot complete_all() users from hardirq context on PREEMPT_RT. The warning as-is will also trigger in interrupt handlers, which are threaded on PREEMPT_RT, which was not intended. Use lockdep_assert_RT_in_threaded_ctx() which triggers in non-preemptive context on PREEMPT_RT. Suggested-by: Peter Zijlstra <peterz@infradead.org> Reported-by: kernel test robot <redacted> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- include/linux/lockdep.h | 15 +++++++++++++++ kernel/sched/completion.c | 2 +- 2 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 425b4ceb7cd07..206774ac69460 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h@@ -711,6 +711,21 @@ do { \ # define lockdep_assert_in_irq() do { } while (0) #endif +#ifdef CONFIG_PROVE_RAW_LOCK_NESTING + +# define lockdep_assert_RT_in_threaded_ctx() do { \ + WARN_ONCE(debug_locks && !current->lockdep_recursion && \ + current->hardirq_context && \ + !(current->hardirq_threaded || current->irq_config), \ + "Not in threaded context on PREEMPT_RT as expected\n"); \ +} while (0) + +#else + +# define lockdep_assert_RT_in_threaded_ctx() do { } while (0) + +#endif + #ifdef CONFIG_LOCKDEP void lockdep_rcu_suspicious(const char *file, const int line, const char *s); #else
diff --git a/kernel/sched/completion.c b/kernel/sched/completion.c
index f15e96164ff1e..a778554f9dad7 100644
--- a/kernel/sched/completion.c
+++ b/kernel/sched/completion.c@@ -58,7 +58,7 @@ void complete_all(struct completion *x) { unsigned long flags; - WARN_ON(irqs_disabled()); + lockdep_assert_RT_in_threaded_ctx(); raw_spin_lock_irqsave(&x->wait.lock, flags); x->done = UINT_MAX;
--
2.26.0.rc2