| /* |
| * Copyright (2004) Linus Torvalds |
| * |
| * Author: Zwane Mwaikambo <zwane@fsmlabs.com> |
| * |
| * Copyright (2004, 2005) Ingo Molnar |
| * |
| * This file contains the spinlock/rwlock implementations for the |
| * SMP and the DEBUG_SPINLOCK cases. (UP-nondebug inlines them) |
| * |
| * Note that some architectures have special knowledge about the |
| * stack frames of these functions in their profile_pc. If you |
| * change anything significant here that could change the stack |
| * frame contact the architecture maintainers. |
| */ |
| |
| #include <linux/linkage.h> |
| #include <linux/preempt.h> |
| #include <linux/spinlock.h> |
| #include <linux/interrupt.h> |
| #include <linux/debug_locks.h> |
| #include <linux/module.h> |
| |
| int __lockfunc _spin_trylock(spinlock_t *lock) |
| { |
| preempt_disable(); |
| if (_raw_spin_trylock(lock)) { |
| spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); |
| return 1; |
| } |
| |
| preempt_enable(); |
| return 0; |
| } |
| EXPORT_SYMBOL(_spin_trylock); |
| |
| int __lockfunc _read_trylock(rwlock_t *lock) |
| { |
| preempt_disable(); |
| if (_raw_read_trylock(lock)) { |
| rwlock_acquire_read(&lock->dep_map, 0, 1, _RET_IP_); |
| return 1; |
| } |
| |
| preempt_enable(); |
| return 0; |
| } |
| EXPORT_SYMBOL(_read_trylock); |
| |
| int __lockfunc _write_trylock(rwlock_t *lock) |
| { |
| preempt_disable(); |
| 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 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_GENERIC_LOCKBREAK) || defined(CONFIG_DEBUG_LOCK_ALLOC) |
| |
| void __lockfunc _read_lock(rwlock_t *lock) |
| { |
| preempt_disable(); |
| rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock); |
| } |
| EXPORT_SYMBOL(_read_lock); |
| |
| unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock) |
| { |
| unsigned long flags; |
| |
| 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_LOCKDEP |
| LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock); |
| #else |
| _raw_spin_lock_flags(lock, &flags); |
| #endif |
| return flags; |
| } |
| EXPORT_SYMBOL(_spin_lock_irqsave); |
| |
| void __lockfunc _spin_lock_irq(spinlock_t *lock) |
| { |
| local_irq_disable(); |
| preempt_disable(); |
| spin_acquire(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock); |
| } |
| EXPORT_SYMBOL(_spin_lock_irq); |
| |
| void __lockfunc _spin_lock_bh(spinlock_t *lock) |
| { |
| local_bh_disable(); |
| preempt_disable(); |
| spin_acquire(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock); |
| } |
| EXPORT_SYMBOL(_spin_lock_bh); |
| |
| unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock) |
| { |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| preempt_disable(); |
| rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock); |
| return flags; |
| } |
| EXPORT_SYMBOL(_read_lock_irqsave); |
| |
| void __lockfunc _read_lock_irq(rwlock_t *lock) |
| { |
| local_irq_disable(); |
| preempt_disable(); |
| rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock); |
| } |
| EXPORT_SYMBOL(_read_lock_irq); |
| |
| void __lockfunc _read_lock_bh(rwlock_t *lock) |
| { |
| local_bh_disable(); |
| preempt_disable(); |
| rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock); |
| } |
| EXPORT_SYMBOL(_read_lock_bh); |
| |
| unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock) |
| { |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| preempt_disable(); |
| rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock); |
| return flags; |
| } |
| EXPORT_SYMBOL(_write_lock_irqsave); |
| |
| void __lockfunc _write_lock_irq(rwlock_t *lock) |
| { |
| local_irq_disable(); |
| preempt_disable(); |
| rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock); |
| } |
| EXPORT_SYMBOL(_write_lock_irq); |
| |
| void __lockfunc _write_lock_bh(rwlock_t *lock) |
| { |
| local_bh_disable(); |
| preempt_disable(); |
| rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock); |
| } |
| EXPORT_SYMBOL(_write_lock_bh); |
| |
| void __lockfunc _spin_lock(spinlock_t *lock) |
| { |
| preempt_disable(); |
| spin_acquire(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock); |
| } |
| |
| EXPORT_SYMBOL(_spin_lock); |
| |
| void __lockfunc _write_lock(rwlock_t *lock) |
| { |
| preempt_disable(); |
| rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_); |
| LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock); |
| } |
| |
| EXPORT_SYMBOL(_write_lock); |
| |
| #else /* CONFIG_PREEMPT: */ |
| |
| /* |
| * This could be a long-held lock. We both prepare to spin for a long |
| * time (making _this_ CPU preemptable if possible), and we also signal |
| * towards that other CPU that it should break the lock ASAP. |
| * |
| * (We do this in a function because inlining it would be excessive.) |
| */ |
| |
| #define BUILD_LOCK_OPS(op, locktype) \ |
| void __lockfunc _##op##_lock(locktype##_t *lock) \ |
| { \ |
| for (;;) { \ |
| preempt_disable(); \ |
| if (likely(_raw_##op##_trylock(lock))) \ |
| break; \ |
| preempt_enable(); \ |
| \ |
| if (!(lock)->break_lock) \ |
| (lock)->break_lock = 1; \ |
| while (!op##_can_lock(lock) && (lock)->break_lock) \ |
| _raw_##op##_relax(&lock->raw_lock); \ |
| } \ |
| (lock)->break_lock = 0; \ |
| } \ |
| \ |
| EXPORT_SYMBOL(_##op##_lock); \ |
| \ |
| unsigned long __lockfunc _##op##_lock_irqsave(locktype##_t *lock) \ |
| { \ |
| unsigned long flags; \ |
| \ |
| for (;;) { \ |
| preempt_disable(); \ |
| local_irq_save(flags); \ |
| if (likely(_raw_##op##_trylock(lock))) \ |
| break; \ |
| local_irq_restore(flags); \ |
| preempt_enable(); \ |
| \ |
| if (!(lock)->break_lock) \ |
| (lock)->break_lock = 1; \ |
| while (!op##_can_lock(lock) && (lock)->break_lock) \ |
| _raw_##op##_relax(&lock->raw_lock); \ |
| } \ |
| (lock)->break_lock = 0; \ |
| return flags; \ |
| } \ |
| \ |
| EXPORT_SYMBOL(_##op##_lock_irqsave); \ |
| \ |
| void __lockfunc _##op##_lock_irq(locktype##_t *lock) \ |
| { \ |
| _##op##_lock_irqsave(lock); \ |
| } \ |
| \ |
| EXPORT_SYMBOL(_##op##_lock_irq); \ |
| \ |
| void __lockfunc _##op##_lock_bh(locktype##_t *lock) \ |
| { \ |
| unsigned long flags; \ |
| \ |
| /* */ \ |
| /* Careful: we must exclude softirqs too, hence the */ \ |
| /* irq-disabling. We use the generic preemption-aware */ \ |
| /* function: */ \ |
| /**/ \ |
| flags = _##op##_lock_irqsave(lock); \ |
| local_bh_disable(); \ |
| local_irq_restore(flags); \ |
| } \ |
| \ |
| EXPORT_SYMBOL(_##op##_lock_bh) |
| |
| /* |
| * Build preemption-friendly versions of the following |
| * lock-spinning functions: |
| * |
| * _[spin|read|write]_lock() |
| * _[spin|read|write]_lock_irq() |
| * _[spin|read|write]_lock_irqsave() |
| * _[spin|read|write]_lock_bh() |
| */ |
| BUILD_LOCK_OPS(spin, spinlock); |
| BUILD_LOCK_OPS(read, rwlock); |
| 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_); |
| LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock); |
| } |
| |
| EXPORT_SYMBOL(_spin_lock_nested); |
| unsigned long __lockfunc _spin_lock_irqsave_nested(spinlock_t *lock, int subclass) |
| { |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| preempt_disable(); |
| spin_acquire(&lock->dep_map, subclass, 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_LOCKDEP |
| LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock); |
| #else |
| _raw_spin_lock_flags(lock, &flags); |
| #endif |
| return flags; |
| } |
| |
| EXPORT_SYMBOL(_spin_lock_irqsave_nested); |
| |
| #endif |
| |
| void __lockfunc _spin_unlock(spinlock_t *lock) |
| { |
| spin_release(&lock->dep_map, 1, _RET_IP_); |
| _raw_spin_unlock(lock); |
| preempt_enable(); |
| } |
| 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(); |
| } |
| 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(); |
| } |
| 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(); |
| } |
| 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(); |
| } |
| 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_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(); |
| } |
| 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(); |
| } |
| 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_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(); |
| } |
| 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(); |
| } |
| 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_ip((unsigned long)__builtin_return_address(0)); |
| } |
| EXPORT_SYMBOL(_write_unlock_bh); |
| |
| int __lockfunc _spin_trylock_bh(spinlock_t *lock) |
| { |
| local_bh_disable(); |
| preempt_disable(); |
| if (_raw_spin_trylock(lock)) { |
| spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); |
| return 1; |
| } |
| |
| preempt_enable_no_resched(); |
| local_bh_enable_ip((unsigned long)__builtin_return_address(0)); |
| return 0; |
| } |
| EXPORT_SYMBOL(_spin_trylock_bh); |
| |
| notrace int in_lock_functions(unsigned long addr) |
| { |
| /* Linker adds these: start and end of __lockfunc functions */ |
| extern char __lock_text_start[], __lock_text_end[]; |
| |
| return addr >= (unsigned long)__lock_text_start |
| && addr < (unsigned long)__lock_text_end; |
| } |
| EXPORT_SYMBOL(in_lock_functions); |