From 23f78d4a03c53cbd75d87a795378ea540aa08c86 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Tue, 27 Jun 2006 02:54:53 -0700 Subject: [PATCH] pi-futex: rt mutex core Core functions for the rt-mutex subsystem. Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Signed-off-by: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/init_task.h | 1 + include/linux/rtmutex.h | 104 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/sched.h | 12 ++++++ include/linux/sysctl.h | 1 + 4 files changed, 118 insertions(+) create mode 100644 include/linux/rtmutex.h (limited to 'include') diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 678c1a90380..3a256957fb5 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -124,6 +124,7 @@ extern struct group_info init_groups; .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \ .fs_excl = ATOMIC_INIT(0), \ .pi_lock = SPIN_LOCK_UNLOCKED, \ + INIT_RT_MUTEXES(tsk) \ } diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h new file mode 100644 index 00000000000..12309c916c6 --- /dev/null +++ b/include/linux/rtmutex.h @@ -0,0 +1,104 @@ +/* + * RT Mutexes: blocking mutual exclusion locks with PI support + * + * started by Ingo Molnar and Thomas Gleixner: + * + * Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar + * Copyright (C) 2006, Timesys Corp., Thomas Gleixner + * + * This file contains the public data structure and API definitions. + */ + +#ifndef __LINUX_RT_MUTEX_H +#define __LINUX_RT_MUTEX_H + +#include +#include +#include + +/* + * The rt_mutex structure + * + * @wait_lock: spinlock to protect the structure + * @wait_list: pilist head to enqueue waiters in priority order + * @owner: the mutex owner + */ +struct rt_mutex { + spinlock_t wait_lock; + struct plist_head wait_list; + struct task_struct *owner; +#ifdef CONFIG_DEBUG_RT_MUTEXES + int save_state; + struct list_head held_list_entry; + unsigned long acquire_ip; + const char *name, *file; + int line; + void *magic; +#endif +}; + +struct rt_mutex_waiter; +struct hrtimer_sleeper; + +#ifdef CONFIG_DEBUG_RT_MUTEXES +# define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \ + , .name = #mutexname, .file = __FILE__, .line = __LINE__ +# define rt_mutex_init(mutex) __rt_mutex_init(mutex, __FUNCTION__) + extern void rt_mutex_debug_task_free(struct task_struct *tsk); +#else +# define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) +# define rt_mutex_init(mutex) __rt_mutex_init(mutex, NULL) +# define rt_mutex_debug_task_free(t) do { } while (0) +#endif + +#define __RT_MUTEX_INITIALIZER(mutexname) \ + { .wait_lock = SPIN_LOCK_UNLOCKED \ + , .wait_list = PLIST_HEAD_INIT(mutexname.wait_list, mutexname.wait_lock) \ + , .owner = NULL \ + __DEBUG_RT_MUTEX_INITIALIZER(mutexname)} + +#define DEFINE_RT_MUTEX(mutexname) \ + struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname) + +/*** + * rt_mutex_is_locked - is the mutex locked + * @lock: the mutex to be queried + * + * Returns 1 if the mutex is locked, 0 if unlocked. + */ +static inline int rt_mutex_is_locked(struct rt_mutex *lock) +{ + return lock->owner != NULL; +} + +extern void __rt_mutex_init(struct rt_mutex *lock, const char *name); +extern void rt_mutex_destroy(struct rt_mutex *lock); + +extern void rt_mutex_lock(struct rt_mutex *lock); +extern int rt_mutex_lock_interruptible(struct rt_mutex *lock, + int detect_deadlock); +extern int rt_mutex_timed_lock(struct rt_mutex *lock, + struct hrtimer_sleeper *timeout, + int detect_deadlock); + +extern int rt_mutex_trylock(struct rt_mutex *lock); + +extern void rt_mutex_unlock(struct rt_mutex *lock); + +#ifdef CONFIG_DEBUG_RT_MUTEXES +# define INIT_RT_MUTEX_DEBUG(tsk) \ + .held_list_head = LIST_HEAD_INIT(tsk.held_list_head), \ + .held_list_lock = SPIN_LOCK_UNLOCKED +#else +# define INIT_RT_MUTEX_DEBUG(tsk) +#endif + +#ifdef CONFIG_RT_MUTEXES +# define INIT_RT_MUTEXES(tsk) \ + .pi_waiters = PLIST_HEAD_INIT(tsk.pi_waiters, tsk.pi_lock), \ + INIT_RT_MUTEX_DEBUG(tsk) +#else +# define INIT_RT_MUTEXES(tsk) +#endif + +#endif diff --git a/include/linux/sched.h b/include/linux/sched.h index 6f167645e7e..6ea23c9af41 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -73,6 +73,7 @@ struct sched_param { #include #include #include +#include #include #include @@ -858,6 +859,17 @@ struct task_struct { /* Protection of the PI data structures: */ spinlock_t pi_lock; +#ifdef CONFIG_RT_MUTEXES + /* PI waiters blocked on a rt_mutex held by this task */ + struct plist_head pi_waiters; + /* Deadlock detection and priority inheritance handling */ + struct rt_mutex_waiter *pi_blocked_on; +# ifdef CONFIG_DEBUG_RT_MUTEXES + spinlock_t held_list_lock; + struct list_head held_list_head; +# endif +#endif + #ifdef CONFIG_DEBUG_MUTEXES /* mutex deadlock detection */ struct mutex_waiter *blocked_on; diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index bee12a7a057..46e4d8f2771 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -149,6 +149,7 @@ enum KERN_ACPI_VIDEO_FLAGS=71, /* int: flags for setting up video after ACPI sleep */ KERN_IA64_UNALIGNED=72, /* int: ia64 unaligned userland trap enable */ KERN_COMPAT_LOG=73, /* int: print compat layer messages */ + KERN_MAX_LOCK_DEPTH=74, }; -- cgit v1.2.3-70-g09d2