From 9a11b49a805665e13a56aa067afaf81d43ec1514 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 3 Jul 2006 00:24:33 -0700 Subject: [PATCH] lockdep: better lock debugging Generic lock debugging: - generalized lock debugging framework. For example, a bug in one lock subsystem turns off debugging in all lock subsystems. - got rid of the caller address passing (__IP__/__IP_DECL__/etc.) from the mutex/rtmutex debugging code: it caused way too much prototype hackery, and lockdep will give the same information anyway. - ability to do silent tests - check lock freeing in vfree too. - more finegrained debugging options, to allow distributions to turn off more expensive debugging features. There's no separate 'held mutexes' list anymore - but there's a 'held locks' stack within lockdep, which unifies deadlock detection across all lock classes. (this is independent of the lockdep validation stuff - lockdep first checks whether we are holding a lock already) Here are the current debugging options: CONFIG_DEBUG_MUTEXES=y CONFIG_DEBUG_LOCK_ALLOC=y which do: config DEBUG_MUTEXES bool "Mutex debugging, basic checks" config DEBUG_LOCK_ALLOC bool "Detect incorrect freeing of live mutexes" Signed-off-by: Ingo Molnar Signed-off-by: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-generic/mutex-null.h | 15 +++------ include/linux/debug_locks.h | 69 ++++++++++++++++++++++++++++++++++++++++ include/linux/init_task.h | 1 - include/linux/mm.h | 8 +---- include/linux/mutex-debug.h | 12 ++----- include/linux/mutex.h | 6 ---- include/linux/rtmutex.h | 10 ------ include/linux/sched.h | 4 --- 8 files changed, 78 insertions(+), 47 deletions(-) create mode 100644 include/linux/debug_locks.h (limited to 'include') diff --git a/include/asm-generic/mutex-null.h b/include/asm-generic/mutex-null.h index 5cf8b7ce0c45..254a126ede5c 100644 --- a/include/asm-generic/mutex-null.h +++ b/include/asm-generic/mutex-null.h @@ -10,15 +10,10 @@ #ifndef _ASM_GENERIC_MUTEX_NULL_H #define _ASM_GENERIC_MUTEX_NULL_H -/* extra parameter only needed for mutex debugging: */ -#ifndef __IP__ -# define __IP__ -#endif - -#define __mutex_fastpath_lock(count, fail_fn) fail_fn(count __RET_IP__) -#define __mutex_fastpath_lock_retval(count, fail_fn) fail_fn(count __RET_IP__) -#define __mutex_fastpath_unlock(count, fail_fn) fail_fn(count __RET_IP__) -#define __mutex_fastpath_trylock(count, fail_fn) fail_fn(count) -#define __mutex_slowpath_needs_to_unlock() 1 +#define __mutex_fastpath_lock(count, fail_fn) fail_fn(count) +#define __mutex_fastpath_lock_retval(count, fail_fn) fail_fn(count) +#define __mutex_fastpath_unlock(count, fail_fn) fail_fn(count) +#define __mutex_fastpath_trylock(count, fail_fn) fail_fn(count) +#define __mutex_slowpath_needs_to_unlock() 1 #endif diff --git a/include/linux/debug_locks.h b/include/linux/debug_locks.h new file mode 100644 index 000000000000..6a7047851e48 --- /dev/null +++ b/include/linux/debug_locks.h @@ -0,0 +1,69 @@ +#ifndef __LINUX_DEBUG_LOCKING_H +#define __LINUX_DEBUG_LOCKING_H + +extern int debug_locks; +extern int debug_locks_silent; + +/* + * Generic 'turn off all lock debugging' function: + */ +extern int debug_locks_off(void); + +/* + * In the debug case we carry the caller's instruction pointer into + * other functions, but we dont want the function argument overhead + * in the nondebug case - hence these macros: + */ +#define _RET_IP_ (unsigned long)__builtin_return_address(0) +#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) + +#define DEBUG_LOCKS_WARN_ON(c) \ +({ \ + int __ret = 0; \ + \ + if (unlikely(c)) { \ + if (debug_locks_off()) \ + WARN_ON(1); \ + __ret = 1; \ + } \ + __ret; \ +}) + +#ifdef CONFIG_SMP +# define SMP_DEBUG_LOCKS_WARN_ON(c) DEBUG_LOCKS_WARN_ON(c) +#else +# define SMP_DEBUG_LOCKS_WARN_ON(c) do { } while (0) +#endif + +#ifdef CONFIG_DEBUG_LOCKING_API_SELFTESTS + extern void locking_selftest(void); +#else +# define locking_selftest() do { } while (0) +#endif + +#ifdef CONFIG_LOCKDEP +extern void debug_show_all_locks(void); +extern void debug_show_held_locks(struct task_struct *task); +extern void debug_check_no_locks_freed(const void *from, unsigned long len); +extern void debug_check_no_locks_held(struct task_struct *task); +#else +static inline void debug_show_all_locks(void) +{ +} + +static inline void debug_show_held_locks(struct task_struct *task) +{ +} + +static inline void +debug_check_no_locks_freed(const void *from, unsigned long len) +{ +} + +static inline void +debug_check_no_locks_held(struct task_struct *task) +{ +} +#endif + +#endif diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 3a256957fb56..678c1a90380d 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -124,7 +124,6 @@ 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/mm.h b/include/linux/mm.h index 75179529e399..990957e0929f 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -14,6 +14,7 @@ #include #include #include +#include struct mempolicy; struct anon_vma; @@ -1034,13 +1035,6 @@ static inline void vm_stat_account(struct mm_struct *mm, } #endif /* CONFIG_PROC_FS */ -static inline void -debug_check_no_locks_freed(const void *from, unsigned long len) -{ - mutex_debug_check_no_locks_freed(from, len); - rt_mutex_debug_check_no_locks_freed(from, len); -} - #ifndef CONFIG_DEBUG_PAGEALLOC static inline void kernel_map_pages(struct page *page, int numpages, int enable) diff --git a/include/linux/mutex-debug.h b/include/linux/mutex-debug.h index 8b5769f00467..70a26091fc73 100644 --- a/include/linux/mutex-debug.h +++ b/include/linux/mutex-debug.h @@ -7,17 +7,11 @@ * Mutexes - debugging helpers: */ -#define __DEBUG_MUTEX_INITIALIZER(lockname) \ - , .held_list = LIST_HEAD_INIT(lockname.held_list), \ - .name = #lockname , .magic = &lockname +#define __DEBUG_MUTEX_INITIALIZER(lockname) \ + , .magic = &lockname -#define mutex_init(sem) __mutex_init(sem, __FUNCTION__) +#define mutex_init(sem) __mutex_init(sem, __FILE__":"#sem) extern void FASTCALL(mutex_destroy(struct mutex *lock)); -extern void mutex_debug_show_all_locks(void); -extern void mutex_debug_show_held_locks(struct task_struct *filter); -extern void mutex_debug_check_no_locks_held(struct task_struct *task); -extern void mutex_debug_check_no_locks_freed(const void *from, unsigned long len); - #endif diff --git a/include/linux/mutex.h b/include/linux/mutex.h index f1ac507fa20d..caafecd5e366 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -50,8 +50,6 @@ struct mutex { struct list_head wait_list; #ifdef CONFIG_DEBUG_MUTEXES struct thread_info *owner; - struct list_head held_list; - unsigned long acquire_ip; const char *name; void *magic; #endif @@ -76,10 +74,6 @@ struct mutex_waiter { # define __DEBUG_MUTEX_INITIALIZER(lockname) # define mutex_init(mutex) __mutex_init(mutex, NULL) # define mutex_destroy(mutex) do { } while (0) -# define mutex_debug_show_all_locks() do { } while (0) -# define mutex_debug_show_held_locks(p) do { } while (0) -# define mutex_debug_check_no_locks_held(task) do { } while (0) -# define mutex_debug_check_no_locks_freed(from, len) do { } while (0) #endif #define __MUTEX_INITIALIZER(lockname) \ diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h index fa4a3b82ba70..5d41dee82f80 100644 --- a/include/linux/rtmutex.h +++ b/include/linux/rtmutex.h @@ -29,8 +29,6 @@ struct rt_mutex { 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; @@ -98,14 +96,6 @@ 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), \ diff --git a/include/linux/sched.h b/include/linux/sched.h index aaf723308ed4..bdabeee10a78 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -865,10 +865,6 @@ struct task_struct { 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 -- cgit v1.2.3