From 8a25d5debff2daee280e83e09d8c25d67c26a972 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 3 Jul 2006 00:24:54 -0700 Subject: [PATCH] lockdep: prove spinlock rwlock locking correctness Use the lock validator framework to prove spinlock and rwlock locking correctness. Signed-off-by: Ingo Molnar Signed-off-by: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/Makefile | 1 + kernel/sched.c | 10 +++++++ kernel/spinlock.c | 79 ++++++++++++++++++++++++++++++++++++++++++++++++------- 3 files changed, 81 insertions(+), 9 deletions(-) (limited to 'kernel') diff --git a/kernel/Makefile b/kernel/Makefile index df6ef3263699..47dbcd570cd8 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -27,6 +27,7 @@ obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o obj-$(CONFIG_SMP) += cpu.o spinlock.o obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o +obj-$(CONFIG_PROVE_LOCKING) += spinlock.o obj-$(CONFIG_UID16) += uid16.o obj-$(CONFIG_MODULES) += module.o obj-$(CONFIG_KALLSYMS) += kallsyms.o diff --git a/kernel/sched.c b/kernel/sched.c index 911829966534..ae4db0185bb2 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -308,6 +308,13 @@ static inline void finish_lock_switch(runqueue_t *rq, task_t *prev) /* this is a valid case when another task releases the spinlock */ rq->lock.owner = current; #endif + /* + * If we are tracking spinlock dependencies then we have to + * fix up the runqueue lock - which gets 'carried over' from + * prev into current: + */ + spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_); + spin_unlock_irq(&rq->lock); } @@ -1778,6 +1785,7 @@ task_t * context_switch(runqueue_t *rq, task_t *prev, task_t *next) WARN_ON(rq->prev_mm); rq->prev_mm = oldmm; } + spin_release(&rq->lock.dep_map, 1, _THIS_IP_); /* Here we just switch the register state and the stack. */ switch_to(prev, next, prev); @@ -4384,6 +4392,7 @@ asmlinkage long sys_sched_yield(void) * no need to preempt or enable interrupts: */ __release(rq->lock); + spin_release(&rq->lock.dep_map, 1, _THIS_IP_); _raw_spin_unlock(&rq->lock); preempt_enable_no_resched(); @@ -4447,6 +4456,7 @@ int cond_resched_lock(spinlock_t *lock) spin_lock(lock); } if (need_resched() && __resched_legal()) { + spin_release(&lock->dep_map, 1, _THIS_IP_); _raw_spin_unlock(lock); preempt_enable_no_resched(); __cond_resched(); diff --git a/kernel/spinlock.c b/kernel/spinlock.c index b31e54eadf56..bfd6ad9c0330 100644 --- a/kernel/spinlock.c +++ b/kernel/spinlock.c @@ -13,6 +13,7 @@ #include #include #include +#include #include /* @@ -29,8 +30,10 @@ EXPORT_SYMBOL(generic__raw_read_trylock); int __lockfunc _spin_trylock(spinlock_t *lock) { preempt_disable(); - if (_raw_spin_trylock(lock)) + if (_raw_spin_trylock(lock)) { + spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); return 1; + } preempt_enable(); return 0; @@ -40,8 +43,10 @@ EXPORT_SYMBOL(_spin_trylock); int __lockfunc _read_trylock(rwlock_t *lock) { preempt_disable(); - if (_raw_read_trylock(lock)) + if (_raw_read_trylock(lock)) { + rwlock_acquire_read(&lock->dep_map, 0, 1, _RET_IP_); return 1; + } preempt_enable(); return 0; @@ -51,19 +56,28 @@ EXPORT_SYMBOL(_read_trylock); int __lockfunc _write_trylock(rwlock_t *lock) { preempt_disable(); - if (_raw_write_trylock(lock)) + if (_raw_write_trylock(lock)) { + rwlock_acquire(&lock->dep_map, 0, 1, _RET_IP_); return 1; + } preempt_enable(); return 0; } EXPORT_SYMBOL(_write_trylock); -#if !defined(CONFIG_PREEMPT) || !defined(CONFIG_SMP) +/* + * If lockdep is enabled then we use the non-preemption spin-ops + * even on CONFIG_PREEMPT, because lockdep assumes that interrupts are + * not re-enabled during lock-acquire (which the preempt-spin-ops do): + */ +#if !defined(CONFIG_PREEMPT) || !defined(CONFIG_SMP) || \ + defined(CONFIG_PROVE_LOCKING) void __lockfunc _read_lock(rwlock_t *lock) { preempt_disable(); + rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_); _raw_read_lock(lock); } EXPORT_SYMBOL(_read_lock); @@ -74,7 +88,17 @@ unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock) local_irq_save(flags); preempt_disable(); + spin_acquire(&lock->dep_map, 0, 0, _RET_IP_); + /* + * On lockdep we dont want the hand-coded irq-enable of + * _raw_spin_lock_flags() code, because lockdep assumes + * that interrupts are not re-enabled during lock-acquire: + */ +#ifdef CONFIG_PROVE_LOCKING + _raw_spin_lock(lock); +#else _raw_spin_lock_flags(lock, &flags); +#endif return flags; } EXPORT_SYMBOL(_spin_lock_irqsave); @@ -83,6 +107,7 @@ void __lockfunc _spin_lock_irq(spinlock_t *lock) { local_irq_disable(); preempt_disable(); + spin_acquire(&lock->dep_map, 0, 0, _RET_IP_); _raw_spin_lock(lock); } EXPORT_SYMBOL(_spin_lock_irq); @@ -91,6 +116,7 @@ void __lockfunc _spin_lock_bh(spinlock_t *lock) { local_bh_disable(); preempt_disable(); + spin_acquire(&lock->dep_map, 0, 0, _RET_IP_); _raw_spin_lock(lock); } EXPORT_SYMBOL(_spin_lock_bh); @@ -101,6 +127,7 @@ unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock) local_irq_save(flags); preempt_disable(); + rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_); _raw_read_lock(lock); return flags; } @@ -110,6 +137,7 @@ void __lockfunc _read_lock_irq(rwlock_t *lock) { local_irq_disable(); preempt_disable(); + rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_); _raw_read_lock(lock); } EXPORT_SYMBOL(_read_lock_irq); @@ -118,6 +146,7 @@ void __lockfunc _read_lock_bh(rwlock_t *lock) { local_bh_disable(); preempt_disable(); + rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_); _raw_read_lock(lock); } EXPORT_SYMBOL(_read_lock_bh); @@ -128,6 +157,7 @@ unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock) local_irq_save(flags); preempt_disable(); + rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_); _raw_write_lock(lock); return flags; } @@ -137,6 +167,7 @@ void __lockfunc _write_lock_irq(rwlock_t *lock) { local_irq_disable(); preempt_disable(); + rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_); _raw_write_lock(lock); } EXPORT_SYMBOL(_write_lock_irq); @@ -145,6 +176,7 @@ void __lockfunc _write_lock_bh(rwlock_t *lock) { local_bh_disable(); preempt_disable(); + rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_); _raw_write_lock(lock); } EXPORT_SYMBOL(_write_lock_bh); @@ -152,6 +184,7 @@ EXPORT_SYMBOL(_write_lock_bh); void __lockfunc _spin_lock(spinlock_t *lock) { preempt_disable(); + spin_acquire(&lock->dep_map, 0, 0, _RET_IP_); _raw_spin_lock(lock); } @@ -160,6 +193,7 @@ EXPORT_SYMBOL(_spin_lock); void __lockfunc _write_lock(rwlock_t *lock) { preempt_disable(); + rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_); _raw_write_lock(lock); } @@ -255,8 +289,22 @@ BUILD_LOCK_OPS(write, rwlock); #endif /* CONFIG_PREEMPT */ +#ifdef CONFIG_DEBUG_LOCK_ALLOC + +void __lockfunc _spin_lock_nested(spinlock_t *lock, int subclass) +{ + preempt_disable(); + spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_); + _raw_spin_lock(lock); +} + +EXPORT_SYMBOL(_spin_lock_nested); + +#endif + void __lockfunc _spin_unlock(spinlock_t *lock) { + spin_release(&lock->dep_map, 1, _RET_IP_); _raw_spin_unlock(lock); preempt_enable(); } @@ -264,6 +312,7 @@ EXPORT_SYMBOL(_spin_unlock); void __lockfunc _write_unlock(rwlock_t *lock) { + rwlock_release(&lock->dep_map, 1, _RET_IP_); _raw_write_unlock(lock); preempt_enable(); } @@ -271,6 +320,7 @@ EXPORT_SYMBOL(_write_unlock); void __lockfunc _read_unlock(rwlock_t *lock) { + rwlock_release(&lock->dep_map, 1, _RET_IP_); _raw_read_unlock(lock); preempt_enable(); } @@ -278,6 +328,7 @@ EXPORT_SYMBOL(_read_unlock); void __lockfunc _spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags) { + spin_release(&lock->dep_map, 1, _RET_IP_); _raw_spin_unlock(lock); local_irq_restore(flags); preempt_enable(); @@ -286,6 +337,7 @@ EXPORT_SYMBOL(_spin_unlock_irqrestore); void __lockfunc _spin_unlock_irq(spinlock_t *lock) { + spin_release(&lock->dep_map, 1, _RET_IP_); _raw_spin_unlock(lock); local_irq_enable(); preempt_enable(); @@ -294,14 +346,16 @@ EXPORT_SYMBOL(_spin_unlock_irq); void __lockfunc _spin_unlock_bh(spinlock_t *lock) { + spin_release(&lock->dep_map, 1, _RET_IP_); _raw_spin_unlock(lock); preempt_enable_no_resched(); - local_bh_enable(); + local_bh_enable_ip((unsigned long)__builtin_return_address(0)); } EXPORT_SYMBOL(_spin_unlock_bh); void __lockfunc _read_unlock_irqrestore(rwlock_t *lock, unsigned long flags) { + rwlock_release(&lock->dep_map, 1, _RET_IP_); _raw_read_unlock(lock); local_irq_restore(flags); preempt_enable(); @@ -310,6 +364,7 @@ EXPORT_SYMBOL(_read_unlock_irqrestore); void __lockfunc _read_unlock_irq(rwlock_t *lock) { + rwlock_release(&lock->dep_map, 1, _RET_IP_); _raw_read_unlock(lock); local_irq_enable(); preempt_enable(); @@ -318,14 +373,16 @@ EXPORT_SYMBOL(_read_unlock_irq); void __lockfunc _read_unlock_bh(rwlock_t *lock) { + rwlock_release(&lock->dep_map, 1, _RET_IP_); _raw_read_unlock(lock); preempt_enable_no_resched(); - local_bh_enable(); + local_bh_enable_ip((unsigned long)__builtin_return_address(0)); } EXPORT_SYMBOL(_read_unlock_bh); void __lockfunc _write_unlock_irqrestore(rwlock_t *lock, unsigned long flags) { + rwlock_release(&lock->dep_map, 1, _RET_IP_); _raw_write_unlock(lock); local_irq_restore(flags); preempt_enable(); @@ -334,6 +391,7 @@ EXPORT_SYMBOL(_write_unlock_irqrestore); void __lockfunc _write_unlock_irq(rwlock_t *lock) { + rwlock_release(&lock->dep_map, 1, _RET_IP_); _raw_write_unlock(lock); local_irq_enable(); preempt_enable(); @@ -342,9 +400,10 @@ EXPORT_SYMBOL(_write_unlock_irq); void __lockfunc _write_unlock_bh(rwlock_t *lock) { + rwlock_release(&lock->dep_map, 1, _RET_IP_); _raw_write_unlock(lock); preempt_enable_no_resched(); - local_bh_enable(); + local_bh_enable_ip((unsigned long)__builtin_return_address(0)); } EXPORT_SYMBOL(_write_unlock_bh); @@ -352,11 +411,13 @@ int __lockfunc _spin_trylock_bh(spinlock_t *lock) { local_bh_disable(); preempt_disable(); - if (_raw_spin_trylock(lock)) + if (_raw_spin_trylock(lock)) { + spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); return 1; + } preempt_enable_no_resched(); - local_bh_enable(); + local_bh_enable_ip((unsigned long)__builtin_return_address(0)); return 0; } EXPORT_SYMBOL(_spin_trylock_bh); -- cgit v1.2.3