diff options
| -rw-r--r-- | drivers/char/sysrq.c | 2 | ||||
| -rw-r--r-- | include/asm-generic/mutex-null.h | 15 | ||||
| -rw-r--r-- | include/linux/debug_locks.h | 69 | ||||
| -rw-r--r-- | include/linux/init_task.h | 1 | ||||
| -rw-r--r-- | include/linux/mm.h | 8 | ||||
| -rw-r--r-- | include/linux/mutex-debug.h | 12 | ||||
| -rw-r--r-- | include/linux/mutex.h | 6 | ||||
| -rw-r--r-- | include/linux/rtmutex.h | 10 | ||||
| -rw-r--r-- | include/linux/sched.h | 4 | ||||
| -rw-r--r-- | init/main.c | 8 | ||||
| -rw-r--r-- | kernel/exit.c | 5 | ||||
| -rw-r--r-- | kernel/fork.c | 4 | ||||
| -rw-r--r-- | kernel/mutex-debug.c | 51 | ||||
| -rw-r--r-- | kernel/mutex-debug.h | 82 | ||||
| -rw-r--r-- | kernel/mutex.c | 52 | ||||
| -rw-r--r-- | kernel/mutex.h | 17 | ||||
| -rw-r--r-- | kernel/rtmutex-debug.c | 302 | ||||
| -rw-r--r-- | kernel/rtmutex-debug.h | 8 | ||||
| -rw-r--r-- | kernel/rtmutex.c | 46 | ||||
| -rw-r--r-- | kernel/rtmutex.h | 3 | ||||
| -rw-r--r-- | kernel/sched.c | 16 | ||||
| -rw-r--r-- | lib/Makefile | 2 | ||||
| -rw-r--r-- | lib/debug_locks.c | 45 | ||||
| -rw-r--r-- | lib/spinlock_debug.c | 62 | ||||
| -rw-r--r-- | mm/vmalloc.c | 2 |
25 files changed, 265 insertions, 567 deletions
diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c index a064ee9181c..e31f079400f 100644 --- a/drivers/char/sysrq.c +++ b/drivers/char/sysrq.c @@ -151,7 +151,7 @@ static struct sysrq_key_op sysrq_mountro_op = { static void sysrq_handle_showlocks(int key, struct pt_regs *pt_regs, struct tty_struct *tty) { - mutex_debug_show_all_locks(); + debug_show_all_locks(); } static struct sysrq_key_op sysrq_showlocks_op = { .handler = sysrq_handle_showlocks, diff --git a/include/asm-generic/mutex-null.h b/include/asm-generic/mutex-null.h index 5cf8b7ce0c4..254a126ede5 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 00000000000..6a7047851e4 --- /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 3a256957fb5..678c1a90380 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 75179529e39..990957e0929 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -14,6 +14,7 @@ #include <linux/prio_tree.h> #include <linux/fs.h> #include <linux/mutex.h> +#include <linux/debug_locks.h> 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 8b5769f0046..70a26091fc7 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 f1ac507fa20..caafecd5e36 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 fa4a3b82ba7..5d41dee82f8 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 aaf723308ed..bdabeee10a7 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 diff --git a/init/main.c b/init/main.c index d604dfef82b..fc73e1cd861 100644 --- a/init/main.c +++ b/init/main.c @@ -47,6 +47,7 @@ #include <linux/key.h> #include <linux/unwind.h> #include <linux/buffer_head.h> +#include <linux/debug_locks.h> #include <asm/io.h> #include <asm/bugs.h> @@ -511,6 +512,13 @@ asmlinkage void __init start_kernel(void) console_init(); if (panic_later) panic(panic_later, panic_param); + /* + * Need to run this when irqs are enabled, because it wants + * to self-test [hard/soft]-irqs on/off lock inversion bugs + * too: + */ + locking_selftest(); + #ifdef CONFIG_BLK_DEV_INITRD if (initrd_start && !initrd_below_start_ok && initrd_start < min_low_pfn << PAGE_SHIFT) { diff --git a/kernel/exit.c b/kernel/exit.c index 7f7ef225855..c595db14cf2 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -933,10 +933,9 @@ fastcall NORET_TYPE void do_exit(long code) if (unlikely(current->pi_state_cache)) kfree(current->pi_state_cache); /* - * If DEBUG_MUTEXES is on, make sure we are holding no locks: + * Make sure we are holding no locks: */ - mutex_debug_check_no_locks_held(tsk); - rt_mutex_debug_check_no_locks_held(tsk); + debug_check_no_locks_held(tsk); if (tsk->io_context) exit_io_context(); diff --git a/kernel/fork.c b/kernel/fork.c index 9064bf9e131..1cd46a4fb0d 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -919,10 +919,6 @@ static inline void rt_mutex_init_task(struct task_struct *p) spin_lock_init(&p->pi_lock); plist_head_init(&p->pi_waiters, &p->pi_lock); p->pi_blocked_on = NULL; -# ifdef CONFIG_DEBUG_RT_MUTEXES - spin_lock_init(&p->held_list_lock); - INIT_LIST_HEAD(&p->held_list_head); -# endif #endif } diff --git a/kernel/mutex-debug.c b/kernel/mutex-debug.c index a92de145ed0..5569766a1ea 100644 --- a/kernel/mutex-debug.c +++ b/kernel/mutex-debug.c @@ -20,52 +20,19 @@ #include <linux/spinlock.h> #include <linux/kallsyms.h> #include <linux/interrupt.h> +#include <linux/debug_locks.h> #include "mutex-debug.h" /* - * We need a global lock when we walk through the multi-process - * lock tree. Only used in the deadlock-debugging case. - */ -DEFINE_SPINLOCK(debug_mutex_lock); - -/* - * All locks held by all tasks, in a single global list: - */ -LIST_HEAD(debug_mutex_held_locks); - -/* - * 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 __IP_DECL__ , unsigned long ip -#define __IP__ , ip -#define __RET_IP__ , (unsigned long)__builtin_return_address(0) - -/* - * "mutex debugging enabled" flag. We turn it off when we detect - * the first problem because we dont want to recurse back - * into the tracing code when doing error printk or - * executing a BUG(): - */ -int debug_mutex_on = 1; - -/* * Must be called with lock->wait_lock held. */ -void debug_mutex_set_owner(struct mutex *lock, - struct thread_info *new_owner __IP_DECL__) +void debug_mutex_set_owner(struct mutex *lock, struct thread_info *new_owner) { lock->owner = new_owner; - DEBUG_LOCKS_WARN_ON(!list_empty(&lock->held_list)); - if (debug_mutex_on) { - list_add_tail(&lock->held_list, &debug_mutex_held_locks); - lock->acquire_ip = ip; - } } -void debug_mutex_init_waiter(struct mutex_waiter *waiter) +void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter) { memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter)); waiter->magic = waiter; @@ -87,9 +54,10 @@ void debug_mutex_free_waiter(struct mutex_waiter *waiter) } void debug_mutex_add_waiter(struct mutex *lock, struct mutex_waiter *waiter, - struct thread_info *ti __IP_DECL__) + struct thread_info *ti) { SMP_DEBUG_LOCKS_WARN_ON(!spin_is_locked(&lock->wait_lock)); + /* Mark the current thread as blocked on the lock: */ ti->task->blocked_on = waiter; waiter->lock = lock; @@ -109,13 +77,10 @@ void mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter, void debug_mutex_unlock(struct mutex *lock) { + DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info()); DEBUG_LOCKS_WARN_ON(lock->magic != lock); DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next); DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info()); - if (debug_mutex_on) { - DEBUG_LOCKS_WARN_ON(list_empty(&lock->held_list)); - list_del_init(&lock->held_list); - } } void debug_mutex_init(struct mutex *lock, const char *name) @@ -123,10 +88,8 @@ void debug_mutex_init(struct mutex *lock, const char *name) /* * Make sure we are not reinitializing a held lock: */ - mutex_debug_check_no_locks_freed((void *)lock, sizeof(*lock)); + debug_check_no_locks_freed((void *)lock, sizeof(*lock)); lock->owner = NULL; - INIT_LIST_HEAD(&lock->held_list); - lock->name = name; lock->magic = lock; } diff --git a/kernel/mutex-debug.h b/kernel/mutex-debug.h index bdab13a9ee2..babfbdfc534 100644 --- a/kernel/mutex-debug.h +++ b/kernel/mutex-debug.h @@ -10,102 +10,44 @@ * More details are in kernel/mutex-debug.c. */ -extern spinlock_t debug_mutex_lock; -extern struct list_head debug_mutex_held_locks; -extern int debug_mutex_on; - -/* - * 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 __IP_DECL__ , unsigned long ip -#define __IP__ , ip -#define __RET_IP__ , (unsigned long)__builtin_return_address(0) - /* * This must be called with lock->wait_lock held. */ -extern void debug_mutex_set_owner(struct mutex *lock, - struct thread_info *new_owner __IP_DECL__); +extern void +debug_mutex_set_owner(struct mutex *lock, struct thread_info *new_owner); static inline void debug_mutex_clear_owner(struct mutex *lock) { lock->owner = NULL; } -extern void debug_mutex_init_waiter(struct mutex_waiter *waiter); +extern void debug_mutex_lock_common(struct mutex *lock, + struct mutex_waiter *waiter); extern void debug_mutex_wake_waiter(struct mutex *lock, struct mutex_waiter *waiter); extern void debug_mutex_free_waiter(struct mutex_waiter *waiter); extern void debug_mutex_add_waiter(struct mutex *lock, struct mutex_waiter *waiter, - struct thread_info *ti __IP_DECL__); + struct thread_info *ti); extern void mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter, struct thread_info *ti); extern void debug_mutex_unlock(struct mutex *lock); -extern void debug_mutex_init(struct mutex *lock, const char *name); - -#define debug_spin_lock_save(lock, flags) \ - do { \ - local_irq_save(flags); \ - if (debug_mutex_on) \ - spin_lock(lock); \ - } while (0) - -#define debug_spin_unlock_restore(lock, flags) \ - do { \ - if (debug_mutex_on) \ - spin_unlock(lock); \ - local_irq_restore(flags); \ - preempt_check_resched(); \ - } while (0) +extern void debug_mutex_init(struct mutex *lock, const char *name, + struct lock_class_key *key); #define spin_lock_mutex(lock, flags) \ do { \ struct mutex *l = container_of(lock, struct mutex, wait_lock); \ \ DEBUG_LOCKS_WARN_ON(in_interrupt()); \ - debug_spin_lock_save(&debug_mutex_lock, flags); \ - spin_lock(lock); \ + local_irq_save(flags); \ + __raw_spin_lock(&(lock)->raw_lock); \ DEBUG_LOCKS_WARN_ON(l->magic != l); \ } while (0) #define spin_unlock_mutex(lock, flags) \ do { \ - spin_unlock(lock); \ - debug_spin_unlock_restore(&debug_mutex_lock, flags); \ + __raw_spin_unlock(&(lock)->raw_lock); \ + local_irq_restore(flags); \ + preempt_check_resched(); \ } while (0) - -#define DEBUG_OFF() \ -do { \ - if (debug_mutex_on) { \ - debug_mutex_on = 0; \ - console_verbose(); \ - if (spin_is_locked(&debug_mutex_lock)) \ - spin_unlock(&debug_mutex_lock); \ - } \ -} while (0) - -#define DEBUG_BUG() \ -do { \ - if (debug_mutex_on) { \ - DEBUG_OFF(); \ - BUG(); \ - } \ -} while (0) - -#define DEBUG_LOCKS_WARN_ON(c) \ -do { \ - if (unlikely(c && debug_mutex_on)) { \ - DEBUG_OFF(); \ - WARN_ON(1); \ - } \ -} while (0) - -#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 - diff --git a/kernel/mutex.c b/kernel/mutex.c index 101ceeb3892..3aad0b7992f 100644 --- a/kernel/mutex.c +++ b/kernel/mutex.c @@ -17,6 +17,7 @@ #include <linux/module.h> #include <linux/spinlock.h> #include <linux/interrupt.h> +#include <linux/debug_locks.h> /* * In the DEBUG case we are using the "NULL fastpath" for mutexes, @@ -38,7 +39,7 @@ * * It is not allowed to initialize an already locked mutex. */ -void fastcall __mutex_init(struct mutex *lock, const char *name) +__always_inline void fastcall __mutex_init(struct mutex *lock, const char *name) { atomic_set(&lock->count, 1); spin_lock_init(&lock->wait_lock); @@ -56,7 +57,7 @@ EXPORT_SYMBOL(__mutex_init); * branch is predicted by the CPU as default-untaken. */ static void fastcall noinline __sched -__mutex_lock_slowpath(atomic_t *lock_count __IP_DECL__); +__mutex_lock_slowpath(atomic_t *lock_count); /*** * mutex_lock - acquire the mutex @@ -79,7 +80,7 @@ __mutex_lock_slowpath(atomic_t *lock_count __IP_DECL__); * * This function is similar to (but not equivalent to) down(). */ -void fastcall __sched mutex_lock(struct mutex *lock) +void inline fastcall __sched mutex_lock(struct mutex *lock) { might_sleep(); /* @@ -92,7 +93,7 @@ void fastcall __sched mutex_lock(struct mutex *lock) EXPORT_SYMBOL(mutex_lock); static void fastcall noinline __sched -__mutex_unlock_slowpath(atomic_t *lock_count __IP_DECL__); +__mutex_unlock_slowpath(atomic_t *lock_count); /*** * mutex_unlock - release the mutex @@ -120,18 +121,17 @@ EXPORT_SYMBOL(mutex_unlock); * Lock a mutex (possibly interruptible), slowpath: */ static inline int __sched -__mutex_lock_common(struct mutex *lock, long state __IP_DECL__) +__mutex_lock_common(struct mutex *lock, long state, unsigned int subclass) { struct task_struct *task = current; struct mutex_waiter waiter; unsigned int old_val; unsigned long flags; - debug_mutex_init_waiter(&waiter); - spin_lock_mutex(&lock->wait_lock, flags); - debug_mutex_add_waiter(lock, &waiter, task->thread_info, ip); + debug_mutex_lock_common(lock, &waiter); + debug_mutex_add_waiter(lock, &waiter, task->thread_info); /* add waiting tasks to the end of the waitqueue (FIFO): */ list_add_tail(&waiter.list, &lock->wait_list); @@ -173,7 +173,7 @@ __mutex_lock_common(struct mutex *lock, long state __IP_DECL__) /* got the lock - rejoice! */ mutex_remove_waiter(lock, &waiter, task->thread_info); - debug_mutex_set_owner(lock, task->thread_info __IP__); + debug_mutex_set_owner(lock, task->thread_info); /* set it to 0 if there are no waiters left: */ if (likely(list_empty(&lock->wait_list))) @@ -183,32 +183,28 @@ __mutex_lock_common(struct mutex *lock, long state __IP_DECL__) debug_mutex_free_waiter(&waiter); - DEBUG_LOCKS_WARN_ON(list_empty(&lock->held_list)); - DEBUG_LOCKS_WARN_ON(lock->owner != task->thread_info); - return 0; } static void fastcall noinline __sched -__mutex_lock_slowpath(atomic_t *lock_count __IP_DECL__) +__mutex_lock_slowpath(atomic_t *lock_count) { struct mutex *lock = container_of(lock_count, struct mutex, count); - __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE __IP__); + __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, 0); } /* * Release the lock, slowpath: */ -static fastcall noinline void -__mutex_unlock_slowpath(atomic_t *lock_count __IP_DECL__) +static fastcall inline void +__mutex_unlock_common_slowpath(atomic_t *lock_count) { struct mutex *lock = container_of(lock_count, struct mutex, count); unsigned long flags; - DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info()); - spin_lock_mutex(&lock->wait_lock, flags); + debug_mutex_unlock(lock); /* * some architectures leave the lock unlocked in the fastpath failure @@ -218,8 +214,6 @@ __mutex_unlock_slowpath(atomic_t *lock_count __IP_DECL__) if (__mutex_slowpath_needs_to_unlock()) atomic_set(&lock->count, 1); - debug_mutex_unlock(lock); - if (!list_empty(&lock->wait_list)) { /* get the first entry from the wait-list: */ struct mutex_waiter *waiter = @@ -237,11 +231,20 @@ __mutex_unlock_slowpath(atomic_t *lock_count __IP_DECL__) } /* + * Release the lock, slowpath: + */ +static fastcall noinline void +__mutex_unlock_slowpath(atomic_t *lock_count) +{ + __mutex_unlock_common_slowpath(lock_count); +} + +/* * Here come the less common (and hence less performance-critical) APIs: * mutex_lock_interruptible() and mutex_trylock(). */ static int fastcall noinline __sched -__mutex_lock_interruptible_slowpath(atomic_t *lock_count __IP_DECL__); +__mutex_lock_interruptible_slowpath(atomic_t *lock_count); /*** * mutex_lock_interruptible - acquire the mutex, interruptable @@ -264,11 +267,11 @@ int fastcall __sched mutex_lock_interruptible(struct mutex *lock) EXPORT_SYMBOL(mutex_lock_interruptible); static int fastcall noinline __sched -__mutex_lock_interruptible_slowpath(atomic_t *lock_count __IP_DECL__) +__mutex_lock_interruptible_slowpath(atomic_t *lock_count) { struct mutex *lock = container_of(lock_count, struct mutex, count); - return __mutex_lock_common(lock, TASK_INTERRUPTIBLE __IP__); + return __mutex_lock_common(lock, TASK_INTERRUPTIBLE, 0); } /* @@ -285,7 +288,8 @@ static inline int __mutex_trylock_slowpath(atomic_t *lock_count) prev = atomic_xchg(&lock->count, -1); if (likely(prev == 1)) - debug_mutex_set_owner(lock, current_thread_info() __RET_IP__); + debug_mutex_set_owner(lock, current_thread_info()); + /* Set it back to 0 if there are no waiters: */ if (likely(list_empty(&lock->wait_list))) atomic_set(&lock->count, 0); diff --git a/kernel/mutex.h b/kernel/mutex.h index 7e1ed48d1a6..aeb2d916aa0 100644 --- a/kernel/mutex.h +++ b/kernel/mutex.h @@ -16,22 +16,15 @@ #define mutex_remove_waiter(lock, waiter, ti) \ __list_del((waiter)->list.prev, (waiter)->list.next) -#define DEBUG_LOCKS_WARN_ON(c) do { } while (0) #define debug_mutex_set_owner(lock, new_owner) do { } while (0) #define debug_mutex_clear_owner(lock) do { } while (0) -#define debug_mutex_init_waiter(waiter) do { } while (0) #define debug_mutex_wake_waiter(lock, waiter) do { } while (0) #define debug_mutex_free_waiter(waiter) do { } while (0) -#define debug_mutex_add_waiter(lock, waiter, ti, ip) do { } while (0) +#define debug_mutex_add_waiter(lock, waiter, ti) do { } while (0) #define debug_mutex_unlock(lock) do { } while (0) #define debug_mutex_init(lock, name) do { } while (0) -/* - * Return-address parameters/declarations. They are very useful for - * debugging, but add overhead in the !DEBUG case - so we go the - * trouble of using this not too elegant but zero-cost solution: - */ -#define __IP_DECL__ -#define __IP__ -#define __RET_IP__ - +static inline void +debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter) +{ +} diff --git a/kernel/rtmutex-debug.c b/kernel/rtmutex-debug.c index 4aa8a2c9f45..353a853bc39 100644 --- a/kernel/rtmutex-debug.c +++ b/kernel/rtmutex-debug.c @@ -26,6 +26,7 @@ #include <linux/interrupt.h> #include <linux/plist.h> #include <linux/fs.h> +#include <linux/debug_locks.h> #include "rtmutex_common.h" @@ -45,8 +46,6 @@ do { \ console_verbose(); \ if (spin_is_locked(¤t->pi_lock)) \ spin_unlock(¤t->pi_lock); \ - if (spin_is_locked(¤t->held_list_lock)) \ - spin_unlock(¤t->held_list_lock); \ } \ } while (0) @@ -105,14 +104,6 @@ static void printk_task(task_t *p) printk("<none>"); } -static void printk_task_short(task_t *p) -{ - if (p) - printk("%s/%d [%p, %3d]", p->comm, p->pid, p, p->prio); - else - printk("<none>"); -} - static void printk_lock(struct rt_mutex *lock, int print_owner) { if (lock->name) @@ -128,222 +119,6 @@ static void printk_lock(struct rt_mutex *lock, int print_owner) printk_task(rt_mutex_owner(lock)); printk("\n"); } - if (rt_mutex_owner(lock)) { - printk("... acquired at: "); - print_symbol("%s\n", lock->acquire_ip); - } -} - -static void printk_waiter(struct rt_mutex_waiter *w) -{ - printk("-------------------------\n"); - printk("| waiter struct %p:\n", w); - printk("| w->list_entry: [DP:%p/%p|SP:%p/%p|PRI:%d]\n", - w->list_entry.plist.prio_list.prev, w->list_entry.plist.prio_list.next, - w->list_entry.plist.node_list.prev, w->list_entry.plist.node_list.next, - w->list_entry.prio); - printk("| w->pi_list_entry: [DP:%p/%p|SP:%p/%p|PRI:%d]\n", - w->pi_list_entry.plist.prio_list.prev, w->pi_list_entry.plist.prio_list.next, - w->pi_list_entry.plist.node_list.prev, w->pi_list_entry.plist.node_list.next, - w->pi_list_entry.prio); - printk("\n| lock:\n"); - printk_lock(w->lock, 1); - printk("| w->ti->task:\n"); - printk_task(w->task); - printk("| blocked at: "); - print_symbol("%s\n", w->ip); - printk("-------------------------\n"); -} - -static void show_task_locks(task_t *p) -{ - switch (p->state) { - case TASK_RUNNING: printk("R"); break; - case TASK_INTERRUPTIBLE: printk("S"); break; - case TASK_UNINTERRUPTIBLE: printk("D"); break; - case TASK_STOPPED: printk("T"); break; - case EXIT_ZOMBIE: printk("Z"); break; - case EXIT_DEAD: printk("X"); break; - default: printk("?"); break; - } - printk_task(p); - if (p->pi_blocked_on) { - struct rt_mutex *lock = p->pi_blocked_on->lock; - - printk(" blocked on:"); - printk_lock(lock, 1); - } else - printk(" (not blocked)\n"); -} - -void rt_mutex_show_held_locks(task_t *task, int verbose) -{ - struct list_head *curr, *cursor = NULL; - struct rt_mutex *lock; - task_t *t; - unsigned long flags; - int count = 0; - - if (!rt_trace_on) - return; - - if (verbose) { - printk("------------------------------\n"); - printk("| showing all locks held by: | ("); - printk_task_short(task); - printk("):\n"); - printk("------------------------------\n"); - } - -next: - spin_lock_irqsave(&task->held_list_lock, flags); - list_for_each(curr, &task->held_list_head) { - if (cursor && curr != cursor) - continue; - lock = list_entry(curr, struct rt_mutex, held_list_entry); - t = rt_mutex_owner(lock); - WARN_ON(t != task); - count++; - cursor = curr->next; - spin_unlock_irqrestore(&task->held_list_lock, flags); - - printk("\n#%03d: ", count); - printk_lock(lock, 0); - goto next; - } - spin_unlock_irqrestore(&task->held_list_lock, flags); - - printk("\n"); -} - -void rt_mutex_show_all_locks(void) -{ - task_t *g, *p; - int count = 10; - int unlock = 1; - - printk("\n"); - printk("----------------------\n"); - printk("| showing all tasks: |\n"); - printk("----------------------\n"); - - /* - * Here we try to get the tasklist_lock as hard as possible, - * if not successful after 2 seconds we ignore it (but keep - * trying). This is to enable a debug printout even if a - * tasklist_lock-holding task deadlocks or crashes. - */ -retry: - if (!read_trylock(&tasklist_lock)) { - if (count == 10) - printk("hm, tasklist_lock locked, retrying... "); - if (count) { - count--; - printk(" #%d", 10-count); - mdelay(200); - goto retry; - } - printk(" ignoring it.\n"); - unlock = 0; - } - if (count != 10) - printk(" locked it.\n"); - - do_each_thread(g, p) { - show_task_locks(p); - if (!unlock) - if (read_trylock(&tasklist_lock)) - unlock = 1; - } while_each_thread(g, p); - - printk("\n"); - - printk("-----------------------------------------\n"); - printk("| showing all locks held in the system: |\n"); - printk("-----------------------------------------\n"); - - do_each_thread(g, p) { - rt_mutex_show_held_locks(p, 0); - if (!unlock) - if (read_trylock(&tasklist_lock)) - unlock = 1; - } while_each_thread(g, p); - - - printk("=============================================\n\n"); - - if (unlock) - read_unlock(&tasklist_lock); -} - -void rt_mutex_debug_check_no_locks_held(task_t *task) -{ - struct rt_mutex_waiter *w; - struct list_head *curr; - struct rt_mutex *lock; - - if (!rt_trace_on) - return; - if (!rt_prio(task->normal_prio) && rt_prio(task->prio)) { - printk("BUG: PI priority boost leaked!\n"); - printk_task(task); - printk("\n"); - } - if (list_empty(&task->held_list_head)) - return; - - spin_lock(&task->pi_lock); - plist_for_each_entry(w, &task->pi_waiters, pi_list_entry) { - TRACE_OFF(); - - printk("hm, PI interest held at exit time? Task:\n"); - printk_task(task); - printk_waiter(w); - return; - } - spin_unlock(&task->pi_lock); - - list_for_each(curr, &task->held_list_head) { - lock = list_entry(curr, struct rt_mutex, held_list_entry); - - printk("BUG: %s/%d, lock held at task exit time!\n", - task->comm, task->pid); - printk_lock(lock, 1); - if (rt_mutex_owner(lock) != task) - printk("exiting task is not even the owner??\n"); - } -} - -int rt_mutex_debug_check_no_locks_freed(const void *from, unsigned long len) -{ - const void *to = from + len; - struct list_head *curr; - struct rt_mutex *lock; - unsigned long flags; - void *lock_addr; - - if (!rt_trace_on) - return 0; - - spin_lock_irqsave(¤t->held_list_lock, flags); - list_for_each(curr, ¤t->held_list_head) { - lock = list_entry(curr, struct rt_mutex, held_list_entry); - lock_addr = lock; - if (lock_addr < from || lock_addr >= to) - continue; - TRACE_OFF(); - - printk("BUG: %s/%d, active lock [%p(%p-%p)] freed!\n", - current->comm, current->pid, lock, from, to); - dump_stack(); - printk_lock(lock, 1); - if (rt_mutex_owner(lock) != current) - printk("freeing task is not even the owner??\n"); - return 1; - } - spin_unlock_irqrestore(¤t->held_list_lock, flags); - - return 0; } void rt_mutex_debug_task_free(struct task_struct *task) @@ -395,85 +170,41 @@ void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter) current->comm, current->pid); printk_lock(waiter->lock, 1); - printk("... trying at: "); - print_symbol("%s\n", waiter->ip); - printk("\n2) %s/%d is blocked on this lock:\n", task->comm, task->pid); printk_lock(waiter->deadlock_lock, 1); - rt_mutex_show_held_locks(current, 1); - rt_mutex_show_held_locks(task, 1); + debug_show_held_locks(current); + debug_show_held_locks(task); printk("\n%s/%d's [blocked] stackdump:\n\n", task->comm, task->pid); show_stack(task, NULL); printk("\n%s/%d's [current] stackdump:\n\n", current->comm, current->pid); dump_stack(); - rt_mutex_show_all_locks(); + debug_show_all_locks(); + printk("[ turning off deadlock detection." "Please report this trace. ]\n\n"); local_irq_disable(); } -void debug_rt_mutex_lock(struct rt_mutex *lock __IP_DECL__) +void debug_rt_mutex_lock(struct rt_mutex *lock) { - unsigned long flags; - - if (rt_trace_on) { - TRACE_WARN_ON_LOCKED(!list_empty(&lock->held_list_entry)); - - spin_lock_irqsave(¤t->held_list_lock, flags); - list_add_tail(&lock->held_list_entry, ¤t->held_list_head); - spin_unlock_irqrestore(¤t->held_list_lock, flags); - - lock->acquire_ip = ip; - } } void debug_rt_mutex_unlock(struct rt_mutex *lock) { - unsigned long flags; - - if (rt_trace_on) { - TRACE_WARN_ON_LOCKED(rt_mutex_owner(lock) != current); - TRACE_WARN_ON_LOCKED(list_empty(&lock->held_list_entry)); - - spin_lock_irqsave(¤t->held_list_lock, flags); - list_del_init(&lock->held_list_entry); - spin_unlock_irqrestore(¤t->held_list_lock, flags); - } + TRACE_WARN_ON_LOCKED(rt_mutex_owner(lock) != current); } -void debug_rt_mutex_proxy_lock(struct rt_mutex *lock, - struct task_struct *powner __IP_DECL__) +void +debug_rt_mutex_proxy_lock(struct rt_mutex *lock, struct task_struct *powner) { - unsigned long flags; - - if (rt_trace_on) { - TRACE_WARN_ON_LOCKED(!list_empty(&lock->held_list_entry)); - - spin_lock_irqsave(&powner->held_list_lock, flags); - list_add_tail(&lock->held_list_entry, &powner->held_list_head); - spin_unlock_irqrestore(&powner->held_list_lock, flags); - - lock->acquire_ip = ip; - } } void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock) { - unsigned long flags; - - if (rt_trace_on) { - struct task_struct *owner = rt_mutex_owner(lock); - - TRACE_WARN_ON_LOCKED(!owner); - TRACE_WARN_ON_LOCKED(list_empty(&lock->held_list_entry)); - - spin_lock_irqsave(&owner->held_list_lock, flags); - list_del_init(&lock->held_list_entry); - spin_unlock_irqrestore(&owner->held_list_lock, flags); - } + TRACE_WARN_ON_LOCKED(!rt_mutex_owner(lock)); } void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter) @@ -493,14 +224,11 @@ void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter) void debug_rt_mutex_init(struct rt_mutex *lock, const char *name) { - void *addr = lock; - - if (rt_trace_on) { - rt_mutex_debug_check_no_locks_freed(addr, - sizeof(struct rt_mutex)); - INIT_LIST_HEAD(&lock->held_list_entry); - lock->name = name; - } + /* + * Make sure we are not reinitializing a held lock: + */ + debug_check_no_locks_freed((void *)lock, sizeof(*lock)); + lock->name = name; } void rt_mutex_deadlock_account_lock(struct rt_mutex *lock, task_t *task) diff --git a/kernel/rtmutex-debug.h b/kernel/rtmutex-debug.h index 7612fbc62d7..14193d596d7 100644 --- a/kernel/rtmutex-debug.h +++ b/kernel/rtmutex-debug.h @@ -9,20 +9,16 @@ * This file contains macros used solely by rtmutex.c. Debug version. */ -#define __IP_DECL__ , unsigned long ip -#define __IP__ , ip -#define __RET_IP__ , (unsigned long)__builtin_return_address(0) - extern void rt_mutex_deadlock_account_lock(struct rt_mutex *lock, struct task_struct *task); extern void rt_mutex_deadlock_account_unlock(struct task_struct *task); extern void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter); extern void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter); extern void debug_rt_mutex_init(struct rt_mutex *lock, const char *name); -extern void debug_rt_mutex_lock(struct rt_mutex *lock __IP_DECL__); +extern void debug_rt_mutex_lock(struct rt_mutex *lock); extern void debug_rt_mutex_unlock(struct rt_mutex *lock); extern void debug_rt_mutex_proxy_lock(struct rt_mutex *lock, - struct task_struct *powner __IP_DECL__); + struct task_struct *powner); extern void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock); extern void debug_rt_mutex_deadlock(int detect, struct rt_mutex_waiter *waiter, struct rt_mutex *lock); diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c index 45d61016da5..91b699aa658 100644 --- a/kernel/rtmutex.c +++ b/kernel/rtmutex.c @@ -161,8 +161,7 @@ static int rt_mutex_adjust_prio_chain(task_t *task, int deadlock_detect, struct rt_mutex *orig_lock, struct rt_mutex_waiter *orig_waiter, - struct task_struct *top_task - __IP_DECL__) + struct task_struct *top_task) { struct rt_mutex *lock; struct rt_mutex_waiter *waiter, *top_waiter = orig_waiter; @@ -357,7 +356,7 @@ static inline int try_to_steal_lock(struct rt_mutex *lock) * * Must be called with lock->wait_lock held. */ -static int try_to_take_rt_mutex(struct rt_mutex *lock __IP_DECL__) +static int try_to_take_rt_mutex(struct rt_mutex *lock) { /* * We have to be careful here if the atomic speedups are @@ -384,7 +383,7 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock __IP_DECL__) return 0; /* We got the lock. */ - debug_rt_mutex_lock(lock __IP__); + debug_rt_mutex_lock(lock); rt_mutex_set_owner(lock, current, 0); @@ -402,8 +401,7 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock __IP_DECL__) */ static int task_blocks_on_rt_mutex(struct rt_mutex *lock, struct rt_mutex_waiter *waiter, - int detect_deadlock - __IP_DECL__) + int detect_deadlock) { struct rt_mutex_waiter *top_waiter = waiter; task_t *owner = rt_mutex_owner(lock); @@ -454,7 +452,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock, spin_unlock(&lock->wait_lock); res = rt_mutex_adjust_prio_chain(owner, detect_deadlock, lock, waiter, - current __IP__); + current); spin_lock(&lock->wait_lock); @@ -526,7 +524,7 @@ static void wakeup_next_waiter(struct rt_mutex *lock) * Must be called with lock->wait_lock held */ static void remove_waiter(struct rt_mutex *lock, - struct rt_mutex_waiter *waiter __IP_DECL__) + struct rt_mutex_waiter *waiter) { int first = (waiter == rt_mutex_top_waiter(lock)); int boost = 0; @@ -568,7 +566,7 @@ static void remove_waiter(struct rt_mutex *lock, spin_unlock(&lock->wait_lock); - rt_mutex_adjust_prio_chain(owner, 0, lock, NULL, current __IP__); + rt_mutex_adjust_prio_chain(owner, 0, lock, NULL, current); spin_lock(&lock->wait_lock); } @@ -595,7 +593,7 @@ void rt_mutex_adjust_pi(struct task_struct *task) get_task_struct(task); spin_unlock_irqrestore(&task->pi_lock, flags); - rt_mutex_adjust_prio_chain(task, 0, NULL, NULL, task __RET_IP__); + rt_mutex_adjust_prio_chain(task, 0, NULL, NULL, task); } /* @@ -604,7 +602,7 @@ void rt_mutex_adjust_pi(struct task_struct *task) static int __sched rt_mutex_slowlock(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - int detect_deadlock __IP_DECL__) + int detect_deadlock) { struct rt_mutex_waiter waiter; int ret = 0; @@ -615,7 +613,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state, spin_lock(&lock->wait_lock); /* Try to acquire the lock again: */ - if (try_to_take_rt_mutex(lock __IP__)) { + if (try_to_take_rt_mutex(lock)) { spin_unlock(&lock->wait_lock); return 0; } @@ -629,7 +627,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state, for (;;) { /* Try to acquire the lock: */ - if (try_to_take_rt_mutex(lock __IP__)) + if (try_to_take_rt_mutex(lock)) break; /* @@ -653,7 +651,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state, */ if (!waiter.task) { ret = task_blocks_on_rt_mutex(lock, &waiter, - detect_deadlock __IP__); + detect_deadlock); /* * If we got woken up by the owner then start loop * all over without going into schedule to try @@ -680,7 +678,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state, set_current_state(TASK_RUNNING); if (unlikely(waiter.task)) - remove_waiter(lock, &waiter __IP__); + remove_waiter(lock, &waiter); /* * try_to_take_rt_mutex() sets the waiter bit @@ -711,7 +709,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state, * Slow path try-lock function: */ static inline int -rt_mutex_slowtrylock(struct rt_mutex *lock __IP_DECL__) +rt_mutex_slowtrylock(struct rt_mutex *lock) { int ret = 0; @@ -719,7 +717,7 @@ rt_mutex_slowtrylock(struct rt_mutex *lock __IP_DECL__) if (likely(rt_mutex_owner(lock) != current)) { - ret = try_to_take_rt_mutex(lock __IP__); + ret = try_to_take_rt_mutex(lock); /* * try_to_take_rt_mutex() sets the lock waiters * bit unconditionally. Clean this up. @@ -769,13 +767,13 @@ rt_mutex_fastlock(struct rt_mutex *lock, int state, int detect_deadlock, int (*slowfn)(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - int detect_deadlock __IP_DECL__)) + int detect_deadlock)) { if (!detect_deadlock && likely(rt_mutex_cmpxchg(lock, NULL, current))) { rt_mutex_deadlock_account_lock(lock, current); return 0; } else - return slowfn(lock, state, NULL, detect_deadlock __RET_IP__); + return slowfn(lock, state, NULL, detect_deadlock); } static inline int @@ -783,24 +781,24 @@ rt_mutex_timed_fastlock(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, int detect_deadlock, int (*slowfn)(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - int detect_deadlock __IP_DECL__)) + int detect_deadlock)) { if (!detect_deadlock && likely(rt_mutex_cmpxchg(lock, NULL, current))) { rt_mutex_deadlock_account_lock(lock, current); return 0; } else - return slowfn(lock, state, timeout, detect_deadlock __RET_IP__); + return slowfn(lock, state, timeout, detect_deadlock); } static inline int rt_mutex_fasttrylock(struct rt_mutex *lock, - int (*slowfn)(struct rt_mutex *lock __IP_DECL__)) + int (*slowfn)(struct rt_mutex *lock)) { if (likely(rt_mutex_cmpxchg(lock, NULL, current))) { rt_mutex_deadlock_account_lock(lock, current); return 1; } - return slowfn(lock __RET_IP__); + return slowfn(lock); } static inline void @@ -948,7 +946,7 @@ void rt_mutex_init_proxy_locked(struct rt_mutex *lock, struct task_struct *proxy_owner) { __rt_mutex_init(lock, NULL); - debug_rt_mutex_proxy_lock(lock, proxy_owner __RET_IP__); + debug_rt_mutex_proxy_lock(lock, proxy_owner); rt_mutex_set_owner(lock, proxy_owner, 0); rt_mutex_deadlock_account_lock(lock, proxy_owner); } diff --git a/kernel/rtmutex.h b/kernel/rtmutex.h index 1e0fca13ff7..a1a1dd06421 100644 --- a/kernel/rtmutex.h +++ b/kernel/rtmutex.h @@ -10,9 +10,6 @@ * Non-debug version. */ -#define __IP_DECL__ -#define __IP__ -#define __RET_IP__ #define rt_mutex_deadlock_check(l) (0) #define rt_mutex_deadlock_account_lock(m, t) do { } while (0) #define rt_mutex_deadlock_account_unlock(l) do { } while (0) diff --git a/kernel/sched.c b/kernel/sched.c index d5e37072ea5..48c1faa60a6 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -30,6 +30,7 @@ #include <linux/capability.h> #include <linux/completion.h> #include <linux/kernel_stat.h> +#include <linux/debug_locks.h> #include <linux/security.h> #include <linux/notifier.h> #include <linux/profile.h> @@ -3142,12 +3143,13 @@ void fastcall add_preempt_count(int val) /* * Underflow? */ - BUG_ON((preempt_count() < 0)); + if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0))) + return; preempt_count() += val; /* * Spinlock count overflowing soon? */ - BUG_ON((preempt_count() & PREEMPT_MASK) >= PREEMPT_MASK-10); + DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >= PREEMPT_MASK-10); } EXPORT_SYMBOL(add_preempt_count); @@ -3156,11 +3158,15 @@ void fastcall sub_preempt_count(int val) /* * Underflow? */ - BUG_ON(val > preempt_count()); + if (DEBUG_LOCKS_WARN_ON(val > preempt_count())) + return; /* * Is the spinlock portion underflowing? */ - BUG_ON((val < PREEMPT_MASK) && !(preempt_count() & PREEMPT_MASK)); + if (DEBUG_LOCKS_WARN_ON((val < PREEMPT_MASK) && + !(preempt_count() & PREEMPT_MASK))) + return; + preempt_count() -= val; } EXPORT_SYMBOL(sub_preempt_count); @@ -4690,7 +4696,7 @@ void show_state(void) } while_each_thread(g, p); read_unlock(&tasklist_lock); - mutex_debug_show_all_locks(); + debug_show_all_locks(); } /** diff --git a/lib/Makefile b/lib/Makefile index 10c13c9d782..4f5d01922f8 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -11,7 +11,7 @@ lib-$(CONFIG_SMP) += cpumask.o lib-y += kobject.o kref.o kobject_uevent.o klist.o -obj-y += sort.o parser.o halfmd4.o iomap_copy.o +obj-y += sort.o parser.o halfmd4.o iomap_copy.o debug_locks.o ifeq ($(CONFIG_DEBUG_KOBJECT),y) CFLAGS_kobject.o += -DDEBUG diff --git a/lib/debug_locks.c b/lib/debug_locks.c new file mode 100644 index 00000000000..0ef01d14727 --- /dev/null +++ b/lib/debug_locks.c @@ -0,0 +1,45 @@ +/* + * lib/debug_locks.c + * + * Generic place for common debugging facilities for various locks: + * spinlocks, rwlocks, mutexes and rwsems. + * + * Started by Ingo Molnar: + * + * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> + */ +#include <linux/rwsem.h> +#include <linux/mutex.h> +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/debug_locks.h> + +/* + * We want to turn all lock-debugging facilities on/off at once, + * via a global flag. The reason is that once a single bug has been + * detected and reported, there might be cascade of followup bugs + * that would just muddy the log. So we report the first one and + * shut up after that. + */ +int debug_locks = 1; + +/* + * The locking-testsuite uses <debug_locks_silent> to get a + * 'silent failure': nothing is printed to the console when + * a locking bug is detected. + */ +int debug_locks_silent; + +/* + * Generic 'turn off all lock debugging' function: + */ +int debug_locks_off(void) +{ + if (xchg(&debug_locks, 0)) { + if (!debug_locks_silent) { + console_verbose(); + return 1; + } + } + return 0; +} diff --git a/lib/spinlock_debug.c b/lib/spinlock_debug.c index 93c15ee3f8e..3de2ccf48ac 100644 --- a/lib/spinlock_debug.c +++ b/lib/spinlock_debug.c @@ -8,38 +8,35 @@ #include <linux/spinlock.h> #include <linux/interrupt.h> +#include <linux/debug_locks.h> #include <linux/delay.h> +#include <linux/module.h> static void spin_bug(spinlock_t *lock, const char *msg) { - static long print_once = 1; struct task_struct *owner = NULL; - if (xchg(&print_once, 0)) { - if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT) - owner = lock->owner; - printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n", - msg, raw_smp_processor_id(), - current->comm, current->pid); - printk(KERN_EMERG " lock: %p, .magic: %08x, .owner: %s/%d, " - ".owner_cpu: %d\n", - lock, lock->magic, - owner ? owner->comm : "<none>", - owner ? owner->pid : -1, - lock->owner_cpu); - dump_stack(); -#ifdef CONFIG_SMP - /* - * We cannot continue on SMP: - */ -// panic("bad locking"); -#endif - } + if (!debug_locks_off()) + return; + + if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT) + owner = lock->owner; + printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n", + msg, raw_smp_processor_id(), + current->comm, current->pid); + printk(KERN_EMERG " lock: %p, .magic: %08x, .owner: %s/%d, " + ".owner_cpu: %d\n", + lock, lock->magic, + owner ? owner->comm : "<none>", + owner ? owner->pid : -1, + lock->owner_cpu); + dump_stack(); } #define SPIN_BUG_ON(cond, lock, msg) if (unlikely(cond)) spin_bug(lock, msg) -static inline void debug_spin_lock_before(spinlock_t *lock) +static inline void +debug_spin_lock_before(spinlock_t *lock) { SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic"); SPIN_BUG_ON(lock->owner == current, lock, "recursion"); @@ -118,20 +115,13 @@ void _raw_spin_unlock(spinlock_t *lock) static void rwlock_bug(rwlock_t *lock, const char *msg) { - static long print_once = 1; - - if (xchg(&print_once, 0)) { - printk(KERN_EMERG "BUG: rwlock %s on CPU#%d, %s/%d, %p\n", - msg, raw_smp_processor_id(), current->comm, - current->pid, lock); - dump_stack(); -#ifdef CONFIG_SMP - /* - * We cannot continue on SMP: - */ - panic("bad locking"); -#endif - } + if (!debug_locks_off()) + return; + + printk(KERN_EMERG "BUG: rwlock %s on CPU#%d, %s/%d, %p\n", + msg, raw_smp_processor_id(), current->comm, + current->pid, lock); + dump_stack(); } #define RWLOCK_BUG_ON(cond, lock, msg) if (unlikely(cond)) rwlock_bug(lock, msg) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 35f8553f893..7b450798b45 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -330,6 +330,8 @@ void __vunmap(void *addr, int deallocate_pages) return; } + debug_check_no_locks_freed(addr, area->size); + if (deallocate_pages) { int i; |