diff options
Diffstat (limited to 'include/linux/spinlock.h')
| -rw-r--r-- | include/linux/spinlock.h | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h index 1341f7d62da4..d3561c4a080e 100644 --- a/include/linux/spinlock.h +++ b/include/linux/spinlock.h @@ -61,6 +61,7 @@ #include <linux/stringify.h> #include <linux/bottom_half.h> #include <linux/lockdep.h> +#include <linux/cleanup.h> #include <asm/barrier.h> #include <asm/mmiowb.h> @@ -455,6 +456,35 @@ static __always_inline int spin_is_contended(spinlock_t *lock) #endif /* CONFIG_PREEMPT_RT */ /* + * Does a critical section need to be broken due to another + * task waiting?: (technically does not depend on CONFIG_PREEMPTION, + * but a general need for low latency) + */ +static inline int spin_needbreak(spinlock_t *lock) +{ + if (!preempt_model_preemptible()) + return 0; + + return spin_is_contended(lock); +} + +/* + * Check if a rwlock is contended. + * Returns non-zero if there is another task waiting on the rwlock. + * Returns zero if the lock is not contended or the system / underlying + * rwlock implementation does not support contention detection. + * Technically does not depend on CONFIG_PREEMPTION, but a general need + * for low latency. + */ +static inline int rwlock_needbreak(rwlock_t *lock) +{ + if (!preempt_model_preemptible()) + return 0; + + return rwlock_is_contended(lock); +} + +/* * Pull the atomic_t declaration: * (asm-mips/atomic.h needs above definitions) */ @@ -476,6 +506,15 @@ extern int _atomic_dec_and_lock_irqsave(atomic_t *atomic, spinlock_t *lock, #define atomic_dec_and_lock_irqsave(atomic, lock, flags) \ __cond_lock(lock, _atomic_dec_and_lock_irqsave(atomic, lock, &(flags))) +extern int _atomic_dec_and_raw_lock(atomic_t *atomic, raw_spinlock_t *lock); +#define atomic_dec_and_raw_lock(atomic, lock) \ + __cond_lock(lock, _atomic_dec_and_raw_lock(atomic, lock)) + +extern int _atomic_dec_and_raw_lock_irqsave(atomic_t *atomic, raw_spinlock_t *lock, + unsigned long *flags); +#define atomic_dec_and_raw_lock_irqsave(atomic, lock, flags) \ + __cond_lock(lock, _atomic_dec_and_raw_lock_irqsave(atomic, lock, &(flags))) + int __alloc_bucket_spinlocks(spinlock_t **locks, unsigned int *lock_mask, size_t max_size, unsigned int cpu_mult, gfp_t gfp, const char *name, @@ -493,5 +532,89 @@ int __alloc_bucket_spinlocks(spinlock_t **locks, unsigned int *lock_mask, void free_bucket_spinlocks(spinlock_t *locks); +DEFINE_LOCK_GUARD_1(raw_spinlock, raw_spinlock_t, + raw_spin_lock(_T->lock), + raw_spin_unlock(_T->lock)) + +DEFINE_LOCK_GUARD_1_COND(raw_spinlock, _try, raw_spin_trylock(_T->lock)) + +DEFINE_LOCK_GUARD_1(raw_spinlock_nested, raw_spinlock_t, + raw_spin_lock_nested(_T->lock, SINGLE_DEPTH_NESTING), + raw_spin_unlock(_T->lock)) + +DEFINE_LOCK_GUARD_1(raw_spinlock_irq, raw_spinlock_t, + raw_spin_lock_irq(_T->lock), + raw_spin_unlock_irq(_T->lock)) + +DEFINE_LOCK_GUARD_1_COND(raw_spinlock_irq, _try, raw_spin_trylock_irq(_T->lock)) + +DEFINE_LOCK_GUARD_1(raw_spinlock_bh, raw_spinlock_t, + raw_spin_lock_bh(_T->lock), + raw_spin_unlock_bh(_T->lock)) + +DEFINE_LOCK_GUARD_1_COND(raw_spinlock_bh, _try, raw_spin_trylock_bh(_T->lock)) + +DEFINE_LOCK_GUARD_1(raw_spinlock_irqsave, raw_spinlock_t, + raw_spin_lock_irqsave(_T->lock, _T->flags), + raw_spin_unlock_irqrestore(_T->lock, _T->flags), + unsigned long flags) + +DEFINE_LOCK_GUARD_1_COND(raw_spinlock_irqsave, _try, + raw_spin_trylock_irqsave(_T->lock, _T->flags)) + +DEFINE_LOCK_GUARD_1(spinlock, spinlock_t, + spin_lock(_T->lock), + spin_unlock(_T->lock)) + +DEFINE_LOCK_GUARD_1_COND(spinlock, _try, spin_trylock(_T->lock)) + +DEFINE_LOCK_GUARD_1(spinlock_irq, spinlock_t, + spin_lock_irq(_T->lock), + spin_unlock_irq(_T->lock)) + +DEFINE_LOCK_GUARD_1_COND(spinlock_irq, _try, + spin_trylock_irq(_T->lock)) + +DEFINE_LOCK_GUARD_1(spinlock_bh, spinlock_t, + spin_lock_bh(_T->lock), + spin_unlock_bh(_T->lock)) + +DEFINE_LOCK_GUARD_1_COND(spinlock_bh, _try, + spin_trylock_bh(_T->lock)) + +DEFINE_LOCK_GUARD_1(spinlock_irqsave, spinlock_t, + spin_lock_irqsave(_T->lock, _T->flags), + spin_unlock_irqrestore(_T->lock, _T->flags), + unsigned long flags) + +DEFINE_LOCK_GUARD_1_COND(spinlock_irqsave, _try, + spin_trylock_irqsave(_T->lock, _T->flags)) + +DEFINE_LOCK_GUARD_1(read_lock, rwlock_t, + read_lock(_T->lock), + read_unlock(_T->lock)) + +DEFINE_LOCK_GUARD_1(read_lock_irq, rwlock_t, + read_lock_irq(_T->lock), + read_unlock_irq(_T->lock)) + +DEFINE_LOCK_GUARD_1(read_lock_irqsave, rwlock_t, + read_lock_irqsave(_T->lock, _T->flags), + read_unlock_irqrestore(_T->lock, _T->flags), + unsigned long flags) + +DEFINE_LOCK_GUARD_1(write_lock, rwlock_t, + write_lock(_T->lock), + write_unlock(_T->lock)) + +DEFINE_LOCK_GUARD_1(write_lock_irq, rwlock_t, + write_lock_irq(_T->lock), + write_unlock_irq(_T->lock)) + +DEFINE_LOCK_GUARD_1(write_lock_irqsave, rwlock_t, + write_lock_irqsave(_T->lock, _T->flags), + write_unlock_irqrestore(_T->lock, _T->flags), + unsigned long flags) + #undef __LINUX_INSIDE_SPINLOCK_H #endif /* __LINUX_SPINLOCK_H */ |