diff options
author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2020-03-21 14:26:02 +0300 |
---|---|---|
committer | Peter Zijlstra <peterz@infradead.org> | 2020-03-21 18:00:24 +0300 |
commit | 40db173965c05a1d803451240ed41707d5bd978d (patch) | |
tree | c5629cb1e7034131b69c247d392e256be5dfc396 | |
parent | de8f5e4f2dc1f032b46afda0a78cab5456974f89 (diff) | |
download | linux-40db173965c05a1d803451240ed41707d5bd978d.tar.xz |
lockdep: Add hrtimer context tracing bits
Set current->irq_config = 1 for hrtimers which are not marked to expire in
hard interrupt context during hrtimer_init(). These timers will expire in
softirq context on PREEMPT_RT.
Setting this allows lockdep to differentiate these timers. If a timer is
marked to expire in hard interrupt context then the timer callback is not
supposed to acquire a regular spinlock instead of a raw_spinlock in the
expiry callback.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113242.534508206@linutronix.de
-rw-r--r-- | include/linux/irqflags.h | 15 | ||||
-rw-r--r-- | include/linux/sched.h | 1 | ||||
-rw-r--r-- | kernel/locking/lockdep.c | 2 | ||||
-rw-r--r-- | kernel/time/hrtimer.c | 6 |
4 files changed, 22 insertions, 2 deletions
diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h index fdaf28601cbe..9c17f9c827aa 100644 --- a/include/linux/irqflags.h +++ b/include/linux/irqflags.h @@ -56,6 +56,19 @@ do { \ do { \ current->softirq_context--; \ } while (0) + +# define lockdep_hrtimer_enter(__hrtimer) \ + do { \ + if (!__hrtimer->is_hard) \ + current->irq_config = 1; \ + } while (0) + +# define lockdep_hrtimer_exit(__hrtimer) \ + do { \ + if (!__hrtimer->is_hard) \ + current->irq_config = 0; \ + } while (0) + #else # define trace_hardirqs_on() do { } while (0) # define trace_hardirqs_off() do { } while (0) @@ -68,6 +81,8 @@ do { \ # define trace_hardirq_exit() do { } while (0) # define lockdep_softirq_enter() do { } while (0) # define lockdep_softirq_exit() do { } while (0) +# define lockdep_hrtimer_enter(__hrtimer) do { } while (0) +# define lockdep_hrtimer_exit(__hrtimer) do { } while (0) #endif #if defined(CONFIG_IRQSOFF_TRACER) || \ diff --git a/include/linux/sched.h b/include/linux/sched.h index 4d3b9ecce074..933914cdf219 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -983,6 +983,7 @@ struct task_struct { unsigned int softirq_enable_event; int softirqs_enabled; int softirq_context; + int irq_config; #endif #ifdef CONFIG_LOCKDEP diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 6b9f9f321e6d..0ebf9807d971 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -4025,7 +4025,7 @@ static int check_wait_context(struct task_struct *curr, struct held_lock *next) /* * Check if force_irqthreads will run us threaded. */ - if (curr->hardirq_threaded) + if (curr->hardirq_threaded || curr->irq_config) curr_inner = LD_WAIT_CONFIG; else curr_inner = LD_WAIT_SPIN; diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 3a609e7344f3..8cce72501aea 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1404,7 +1404,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, base = softtimer ? HRTIMER_MAX_CLOCK_BASES / 2 : 0; base += hrtimer_clockid_to_base(clock_id); timer->is_soft = softtimer; - timer->is_hard = !softtimer; + timer->is_hard = !!(mode & HRTIMER_MODE_HARD); timer->base = &cpu_base->clock_base[base]; timerqueue_init(&timer->node); } @@ -1514,7 +1514,11 @@ static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base, */ raw_spin_unlock_irqrestore(&cpu_base->lock, flags); trace_hrtimer_expire_entry(timer, now); + lockdep_hrtimer_enter(timer); + restart = fn(timer); + + lockdep_hrtimer_exit(timer); trace_hrtimer_expire_exit(timer); raw_spin_lock_irq(&cpu_base->lock); |