Commit-ID: 62cedf3e60af03e47849fe2bd6a03ec179422a8a Gitweb: https://git.kernel.org/tip/62cedf3e60af03e47849fe2bd6a03ec179422a8a Author: Peter Rosin <p...@axentia.se> AuthorDate: Fri, 20 Jul 2018 10:39:13 +0200 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Wed, 25 Jul 2018 11:22:19 +0200
locking/rtmutex: Allow specifying a subclass for nested locking Needed for annotating rt_mutex locks. Tested-by: John Sperbeck <jsperb...@google.com> Signed-off-by: Peter Rosin <p...@axentia.se> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Davidlohr Bueso <d...@stgolabs.net> Cc: Deepa Dinamani <deepadinam...@google.com> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Chang <d...@google.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Philippe Ombredanne <pombreda...@nexb.com> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Will Deacon <will.dea...@arm.com> Cc: Wolfram Sang <w...@the-dreams.de> Link: http://lkml.kernel.org/r/20180720083914.1950-2-p...@axentia.se Signed-off-by: Ingo Molnar <mi...@kernel.org> --- include/linux/rtmutex.h | 7 +++++++ kernel/locking/rtmutex.c | 29 +++++++++++++++++++++++++---- 2 files changed, 32 insertions(+), 4 deletions(-) diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h index 1b92a28dd672..6fd615a0eea9 100644 --- a/include/linux/rtmutex.h +++ b/include/linux/rtmutex.h @@ -106,7 +106,14 @@ static inline int rt_mutex_is_locked(struct rt_mutex *lock) extern void __rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_class_key *key); extern void rt_mutex_destroy(struct rt_mutex *lock); +#ifdef CONFIG_DEBUG_LOCK_ALLOC +extern void rt_mutex_lock_nested(struct rt_mutex *lock, unsigned int subclass); +#define rt_mutex_lock(lock) rt_mutex_lock_nested(lock, 0) +#else extern void rt_mutex_lock(struct rt_mutex *lock); +#define rt_mutex_lock_nested(lock, subclass) rt_mutex_lock(lock) +#endif + extern int rt_mutex_lock_interruptible(struct rt_mutex *lock); extern int rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout); diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 4f014be7a4b8..2823d4163a37 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -1465,6 +1465,29 @@ rt_mutex_fastunlock(struct rt_mutex *lock, rt_mutex_postunlock(&wake_q); } +static inline void __rt_mutex_lock(struct rt_mutex *lock, unsigned int subclass) +{ + might_sleep(); + + mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_); + rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock); +} + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +/** + * rt_mutex_lock_nested - lock a rt_mutex + * + * @lock: the rt_mutex to be locked + * @subclass: the lockdep subclass + */ +void __sched rt_mutex_lock_nested(struct rt_mutex *lock, unsigned int subclass) +{ + __rt_mutex_lock(lock, subclass); +} +EXPORT_SYMBOL_GPL(rt_mutex_lock_nested); +#endif + +#ifndef CONFIG_DEBUG_LOCK_ALLOC /** * rt_mutex_lock - lock a rt_mutex * @@ -1472,12 +1495,10 @@ rt_mutex_fastunlock(struct rt_mutex *lock, */ void __sched rt_mutex_lock(struct rt_mutex *lock) { - might_sleep(); - - mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_); - rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock); + __rt_mutex_lock(lock, 0); } EXPORT_SYMBOL_GPL(rt_mutex_lock); +#endif /** * rt_mutex_lock_interruptible - lock a rt_mutex interruptible
