diff options
Diffstat (limited to 'features/rt/locking-rtmutex-Allow-rt_mutex_trylock-on-PREEMPT_RT.patch')
| -rw-r--r-- | features/rt/locking-rtmutex-Allow-rt_mutex_trylock-on-PREEMPT_RT.patch | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/features/rt/locking-rtmutex-Allow-rt_mutex_trylock-on-PREEMPT_RT.patch b/features/rt/locking-rtmutex-Allow-rt_mutex_trylock-on-PREEMPT_RT.patch new file mode 100644 index 00000000..2e0997d6 --- /dev/null +++ b/features/rt/locking-rtmutex-Allow-rt_mutex_trylock-on-PREEMPT_RT.patch @@ -0,0 +1,36 @@ +From 50f8ea4c311b4bc5100595c2c43f02754afa2798 Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Wed, 2 Dec 2015 11:34:07 +0100 +Subject: [PATCH 076/191] locking/rtmutex: Allow rt_mutex_trylock() on + PREEMPT_RT + +Non PREEMPT_RT kernel can deadlock on rt_mutex_trylock() in softirq +context. +On PREEMPT_RT the softirq context is handled in thread context. This +avoids the deadlock in the slow path and PI-boosting will be done on the +correct thread. + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + kernel/locking/rtmutex.c | 4 ++++ + 1 file changed, 4 insertions(+) + +diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c +index 03ffb955b286..f0bc7fcae441 100644 +--- a/kernel/locking/rtmutex.c ++++ b/kernel/locking/rtmutex.c +@@ -1866,7 +1866,11 @@ int __sched __rt_mutex_futex_trylock(struct rt_mutex *lock) + + int __sched __rt_mutex_trylock(struct rt_mutex *lock) + { ++#ifdef CONFIG_PREEMPT_RT ++ if (WARN_ON_ONCE(in_irq() || in_nmi())) ++#else + if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq())) ++#endif + return 0; + + return rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock); +-- +2.19.1 + |