diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/asm-generic/atomic-long.h | 263 | ||||
| -rw-r--r-- | include/asm-generic/atomic.h | 11 | ||||
| -rw-r--r-- | include/asm-generic/atomic64.h | 4 | ||||
| -rw-r--r-- | include/asm-generic/barrier.h | 4 | ||||
| -rw-r--r-- | include/asm-generic/qrwlock.h | 78 | ||||
| -rw-r--r-- | include/linux/atomic.h | 361 | ||||
| -rw-r--r-- | include/linux/compiler.h | 7 | ||||
| -rw-r--r-- | include/linux/jump_label.h | 261 | ||||
| -rw-r--r-- | include/linux/llist.h | 2 |
9 files changed, 705 insertions, 286 deletions
diff --git a/include/asm-generic/atomic-long.h b/include/asm-generic/atomic-long.h index b7babf0206b8..a94cbebbc33d 100644 --- a/include/asm-generic/atomic-long.h +++ b/include/asm-generic/atomic-long.h @@ -23,236 +23,159 @@ typedef atomic64_t atomic_long_t; #define ATOMIC_LONG_INIT(i) ATOMIC64_INIT(i) +#define ATOMIC_LONG_PFX(x) atomic64 ## x -static inline long atomic_long_read(atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - return (long)atomic64_read(v); -} - -static inline void atomic_long_set(atomic_long_t *l, long i) -{ - atomic64_t *v = (atomic64_t *)l; - - atomic64_set(v, i); -} - -static inline void atomic_long_inc(atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - atomic64_inc(v); -} - -static inline void atomic_long_dec(atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - atomic64_dec(v); -} - -static inline void atomic_long_add(long i, atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - atomic64_add(i, v); -} - -static inline void atomic_long_sub(long i, atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - atomic64_sub(i, v); -} - -static inline int atomic_long_sub_and_test(long i, atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - return atomic64_sub_and_test(i, v); -} - -static inline int atomic_long_dec_and_test(atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - return atomic64_dec_and_test(v); -} - -static inline int atomic_long_inc_and_test(atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - return atomic64_inc_and_test(v); -} - -static inline int atomic_long_add_negative(long i, atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - return atomic64_add_negative(i, v); -} - -static inline long atomic_long_add_return(long i, atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - return (long)atomic64_add_return(i, v); -} - -static inline long atomic_long_sub_return(long i, atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - return (long)atomic64_sub_return(i, v); -} - -static inline long atomic_long_inc_return(atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - return (long)atomic64_inc_return(v); -} - -static inline long atomic_long_dec_return(atomic_long_t *l) -{ - atomic64_t *v = (atomic64_t *)l; - - return (long)atomic64_dec_return(v); -} - -static inline long atomic_long_add_unless(atomic_long_t *l, long a, long u) -{ - atomic64_t *v = (atomic64_t *)l; - - return (long)atomic64_add_unless(v, a, u); -} - -#define atomic_long_inc_not_zero(l) atomic64_inc_not_zero((atomic64_t *)(l)) - -#define atomic_long_cmpxchg(l, old, new) \ - (atomic64_cmpxchg((atomic64_t *)(l), (old), (new))) -#define atomic_long_xchg(v, new) \ - (atomic64_xchg((atomic64_t *)(v), (new))) - -#else /* BITS_PER_LONG == 64 */ +#else typedef atomic_t atomic_long_t; #define ATOMIC_LONG_INIT(i) ATOMIC_INIT(i) -static inline long atomic_long_read(atomic_long_t *l) -{ - atomic_t *v = (atomic_t *)l; - - return (long)atomic_read(v); -} - -static inline void atomic_long_set(atomic_long_t *l, long i) -{ - atomic_t *v = (atomic_t *)l; - - atomic_set(v, i); -} +#define ATOMIC_LONG_PFX(x) atomic ## x + +#endif + +#define ATOMIC_LONG_READ_OP(mo) \ +static inline long atomic_long_read##mo(atomic_long_t *l) \ +{ \ + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; \ + \ + return (long)ATOMIC_LONG_PFX(_read##mo)(v); \ +} +ATOMIC_LONG_READ_OP() +ATOMIC_LONG_READ_OP(_acquire) + +#undef ATOMIC_LONG_READ_OP + +#define ATOMIC_LONG_SET_OP(mo) \ +static inline void atomic_long_set##mo(atomic_long_t *l, long i) \ +{ \ + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; \ + \ + ATOMIC_LONG_PFX(_set##mo)(v, i); \ +} +ATOMIC_LONG_SET_OP() +ATOMIC_LONG_SET_OP(_release) + +#undef ATOMIC_LONG_SET_OP + +#define ATOMIC_LONG_ADD_SUB_OP(op, mo) \ +static inline long \ +atomic_long_##op##_return##mo(long i, atomic_long_t *l) \ +{ \ + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; \ + \ + return (long)ATOMIC_LONG_PFX(_##op##_return##mo)(i, v); \ +} +ATOMIC_LONG_ADD_SUB_OP(add,) +ATOMIC_LONG_ADD_SUB_OP(add, _relaxed) +ATOMIC_LONG_ADD_SUB_OP(add, _acquire) +ATOMIC_LONG_ADD_SUB_OP(add, _release) +ATOMIC_LONG_ADD_SUB_OP(sub,) +ATOMIC_LONG_ADD_SUB_OP(sub, _relaxed) +ATOMIC_LONG_ADD_SUB_OP(sub, _acquire) +ATOMIC_LONG_ADD_SUB_OP(sub, _release) + +#undef ATOMIC_LONG_ADD_SUB_OP + +#define atomic_long_cmpxchg_relaxed(l, old, new) \ + (ATOMIC_LONG_PFX(_cmpxchg_relaxed)((ATOMIC_LONG_PFX(_t) *)(l), \ + (old), (new))) +#define atomic_long_cmpxchg_acquire(l, old, new) \ + (ATOMIC_LONG_PFX(_cmpxchg_acquire)((ATOMIC_LONG_PFX(_t) *)(l), \ + (old), (new))) +#define atomic_long_cmpxchg_release(l, old, new) \ + (ATOMIC_LONG_PFX(_cmpxchg_release)((ATOMIC_LONG_PFX(_t) *)(l), \ + (old), (new))) +#define atomic_long_cmpxchg(l, old, new) \ + (ATOMIC_LONG_PFX(_cmpxchg)((ATOMIC_LONG_PFX(_t) *)(l), (old), (new))) + +#define atomic_long_xchg_relaxed(v, new) \ + (ATOMIC_LONG_PFX(_xchg_relaxed)((ATOMIC_LONG_PFX(_t) *)(v), (new))) +#define atomic_long_xchg_acquire(v, new) \ + (ATOMIC_LONG_PFX(_xchg_acquire)((ATOMIC_LONG_PFX(_t) *)(v), (new))) +#define atomic_long_xchg_release(v, new) \ + (ATOMIC_LONG_PFX(_xchg_release)((ATOMIC_LONG_PFX(_t) *)(v), (new))) +#define atomic_long_xchg(v, new) \ + (ATOMIC_LONG_PFX(_xchg)((ATOMIC_LONG_PFX(_t) *)(v), (new))) static inline void atomic_long_inc(atomic_long_t *l) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - atomic_inc(v); + ATOMIC_LONG_PFX(_inc)(v); } static inline void atomic_long_dec(atomic_long_t *l) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - atomic_dec(v); + ATOMIC_LONG_PFX(_dec)(v); } static inline void atomic_long_add(long i, atomic_long_t *l) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - atomic_add(i, v); + ATOMIC_LONG_PFX(_add)(i, v); } static inline void atomic_long_sub(long i, atomic_long_t *l) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - atomic_sub(i, v); + ATOMIC_LONG_PFX(_sub)(i, v); } static inline int atomic_long_sub_and_test(long i, atomic_long_t *l) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - return atomic_sub_and_test(i, v); + return ATOMIC_LONG_PFX(_sub_and_test)(i, v); } static inline int atomic_long_dec_and_test(atomic_long_t *l) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - return atomic_dec_and_test(v); + return ATOMIC_LONG_PFX(_dec_and_test)(v); } static inline int atomic_long_inc_and_test(atomic_long_t *l) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - return atomic_inc_and_test(v); + return ATOMIC_LONG_PFX(_inc_and_test)(v); } static inline int atomic_long_add_negative(long i, atomic_long_t *l) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - return atomic_add_negative(i, v); -} - -static inline long atomic_long_add_return(long i, atomic_long_t *l) -{ - atomic_t *v = (atomic_t *)l; - - return (long)atomic_add_return(i, v); -} - -static inline long atomic_long_sub_return(long i, atomic_long_t *l) -{ - atomic_t *v = (atomic_t *)l; - - return (long)atomic_sub_return(i, v); + return ATOMIC_LONG_PFX(_add_negative)(i, v); } static inline long atomic_long_inc_return(atomic_long_t *l) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - return (long)atomic_inc_return(v); + return (long)ATOMIC_LONG_PFX(_inc_return)(v); } static inline long atomic_long_dec_return(atomic_long_t *l) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - return (long)atomic_dec_return(v); + return (long)ATOMIC_LONG_PFX(_dec_return)(v); } static inline long atomic_long_add_unless(atomic_long_t *l, long a, long u) { - atomic_t *v = (atomic_t *)l; + ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; - return (long)atomic_add_unless(v, a, u); + return (long)ATOMIC_LONG_PFX(_add_unless)(v, a, u); } -#define atomic_long_inc_not_zero(l) atomic_inc_not_zero((atomic_t *)(l)) - -#define atomic_long_cmpxchg(l, old, new) \ - (atomic_cmpxchg((atomic_t *)(l), (old), (new))) -#define atomic_long_xchg(v, new) \ - (atomic_xchg((atomic_t *)(v), (new))) - -#endif /* BITS_PER_LONG == 64 */ +#define atomic_long_inc_not_zero(l) \ + ATOMIC_LONG_PFX(_inc_not_zero)((ATOMIC_LONG_PFX(_t) *)(l)) #endif /* _ASM_GENERIC_ATOMIC_LONG_H */ diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h index 1973ad2b13f4..d4d7e337fdcb 100644 --- a/include/asm-generic/atomic.h +++ b/include/asm-generic/atomic.h @@ -98,15 +98,16 @@ ATOMIC_OP_RETURN(add, +) ATOMIC_OP_RETURN(sub, -) #endif -#ifndef atomic_clear_mask +#ifndef atomic_and ATOMIC_OP(and, &) -#define atomic_clear_mask(i, v) atomic_and(~(i), (v)) #endif -#ifndef atomic_set_mask -#define CONFIG_ARCH_HAS_ATOMIC_OR +#ifndef atomic_or ATOMIC_OP(or, |) -#define atomic_set_mask(i, v) atomic_or((i), (v)) +#endif + +#ifndef atomic_xor +ATOMIC_OP(xor, ^) #endif #undef ATOMIC_OP_RETURN diff --git a/include/asm-generic/atomic64.h b/include/asm-generic/atomic64.h index 30ad9c86cebb..d48e78ccad3d 100644 --- a/include/asm-generic/atomic64.h +++ b/include/asm-generic/atomic64.h @@ -32,6 +32,10 @@ extern long long atomic64_##op##_return(long long a, atomic64_t *v); ATOMIC64_OPS(add) ATOMIC64_OPS(sub) +ATOMIC64_OP(and) +ATOMIC64_OP(or) +ATOMIC64_OP(xor) + #undef ATOMIC64_OPS #undef ATOMIC64_OP_RETURN #undef ATOMIC64_OP diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h index 55e3abc2d027..b42afada1280 100644 --- a/include/asm-generic/barrier.h +++ b/include/asm-generic/barrier.h @@ -108,12 +108,12 @@ do { \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ ___p1; \ diff --git a/include/asm-generic/qrwlock.h b/include/asm-generic/qrwlock.h index 6383d54bf983..54a8e65e18b6 100644 --- a/include/asm-generic/qrwlock.h +++ b/include/asm-generic/qrwlock.h @@ -36,39 +36,39 @@ /* * External function declarations */ -extern void queue_read_lock_slowpath(struct qrwlock *lock); -extern void queue_write_lock_slowpath(struct qrwlock *lock); +extern void queued_read_lock_slowpath(struct qrwlock *lock, u32 cnts); +extern void queued_write_lock_slowpath(struct qrwlock *lock); /** - * queue_read_can_lock- would read_trylock() succeed? + * queued_read_can_lock- would read_trylock() succeed? * @lock: Pointer to queue rwlock structure */ -static inline int queue_read_can_lock(struct qrwlock *lock) +static inline int queued_read_can_lock(struct qrwlock *lock) { return !(atomic_read(&lock->cnts) & _QW_WMASK); } /** - * queue_write_can_lock- would write_trylock() succeed? + * queued_write_can_lock- would write_trylock() succeed? * @lock: Pointer to queue rwlock structure */ -static inline int queue_write_can_lock(struct qrwlock *lock) +static inline int queued_write_can_lock(struct qrwlock *lock) { return !atomic_read(&lock->cnts); } /** - * queue_read_trylock - try to acquire read lock of a queue rwlock + * queued_read_trylock - try to acquire read lock of a queue rwlock * @lock : Pointer to queue rwlock structure * Return: 1 if lock acquired, 0 if failed */ -static inline int queue_read_trylock(struct qrwlock *lock) +static inline int queued_read_trylock(struct qrwlock *lock) { u32 cnts; cnts = atomic_read(&lock->cnts); if (likely(!(cnts & _QW_WMASK))) { - cnts = (u32)atomic_add_return(_QR_BIAS, &lock->cnts); + cnts = (u32)atomic_add_return_acquire(_QR_BIAS, &lock->cnts); if (likely(!(cnts & _QW_WMASK))) return 1; atomic_sub(_QR_BIAS, &lock->cnts); @@ -77,11 +77,11 @@ static inline int queue_read_trylock(struct qrwlock *lock) } /** - * queue_write_trylock - try to acquire write lock of a queue rwlock + * queued_write_trylock - try to acquire write lock of a queue rwlock * @lock : Pointer to queue rwlock structure * Return: 1 if lock acquired, 0 if failed */ -static inline int queue_write_trylock(struct qrwlock *lock) +static inline int queued_write_trylock(struct qrwlock *lock) { u32 cnts; @@ -89,78 +89,70 @@ static inline int queue_write_trylock(struct qrwlock *lock) if (unlikely(cnts)) return 0; - return likely(atomic_cmpxchg(&lock->cnts, - cnts, cnts | _QW_LOCKED) == cnts); + return likely(atomic_cmpxchg_acquire(&lock->cnts, + cnts, cnts | _QW_LOCKED) == cnts); } /** - * queue_read_lock - acquire read lock of a queue rwlock + * queued_read_lock - acquire read lock of a queue rwlock * @lock: Pointer to queue rwlock structure */ -static inline void queue_read_lock(struct qrwlock *lock) +static inline void queued_read_lock(struct qrwlock *lock) { u32 cnts; - cnts = atomic_add_return(_QR_BIAS, &lock->cnts); + cnts = atomic_add_return_acquire(_QR_BIAS, &lock->cnts); if (likely(!(cnts & _QW_WMASK))) return; /* The slowpath will decrement the reader count, if necessary. */ - queue_read_lock_slowpath(lock); + queued_read_lock_slowpath(lock, cnts); } /** - * queue_write_lock - acquire write lock of a queue rwlock + * queued_write_lock - acquire write lock of a queue rwlock * @lock : Pointer to queue rwlock structure */ -static inline void queue_write_lock(struct qrwlock *lock) +static inline void queued_write_lock(struct qrwlock *lock) { /* Optimize for the unfair lock case where the fair flag is 0. */ - if (atomic_cmpxchg(&lock->cnts, 0, _QW_LOCKED) == 0) + if (atomic_cmpxchg_acquire(&lock->cnts, 0, _QW_LOCKED) == 0) return; - queue_write_lock_slowpath(lock); + queued_write_lock_slowpath(lock); } /** - * queue_read_unlock - release read lock of a queue rwlock + * queued_read_unlock - release read lock of a queue rwlock * @lock : Pointer to queue rwlock structure */ -static inline void queue_read_unlock(struct qrwlock *lock) +static inline void queued_read_unlock(struct qrwlock *lock) { /* * Atomically decrement the reader count */ - smp_mb__before_atomic(); - atomic_sub(_QR_BIAS, &lock->cnts); + (void)atomic_sub_return_release(_QR_BIAS, &lock->cnts); } -#ifndef queue_write_unlock /** - * queue_write_unlock - release write lock of a queue rwlock + * queued_write_unlock - release write lock of a queue rwlock * @lock : Pointer to queue rwlock structure */ -static inline void queue_write_unlock(struct qrwlock *lock) +static inline void queued_write_unlock(struct qrwlock *lock) { - /* - * If the writer field is atomic, it can be cleared directly. - * Otherwise, an atomic subtraction will be used to clear it. - */ - smp_mb__before_atomic(); - atomic_sub(_QW_LOCKED, &lock->cnts); + smp_store_release((u8 *)&lock->cnts, 0); } -#endif /* * Remapping rwlock architecture specific functions to the corresponding * queue rwlock functions. */ -#define arch_read_can_lock(l) queue_read_can_lock(l) -#define arch_write_can_lock(l) queue_write_can_lock(l) -#define arch_read_lock(l) queue_read_lock(l) -#define arch_write_lock(l) queue_write_lock(l) -#define arch_read_trylock(l) queue_read_trylock(l) -#define arch_write_trylock(l) queue_write_trylock(l) -#define arch_read_unlock(l) queue_read_unlock(l) -#define arch_write_unlock(l) queue_write_unlock(l) +#define arch_read_can_lock(l) queued_read_can_lock(l) +#define arch_write_can_lock(l) queued_write_can_lock(l) +#define arch_read_lock(l) queued_read_lock(l) +#define arch_write_lock(l) queued_write_lock(l) +#define arch_read_trylock(l) queued_read_trylock(l) +#define arch_write_trylock(l) queued_write_trylock(l) +#define arch_read_unlock(l) queued_read_unlock(l) +#define arch_write_unlock(l) queued_write_unlock(l) #endif /* __ASM_GENERIC_QRWLOCK_H */ diff --git a/include/linux/atomic.h b/include/linux/atomic.h index 5b08a8540ecf..00a5763e850e 100644 --- a/include/linux/atomic.h +++ b/include/linux/atomic.h @@ -2,6 +2,329 @@ #ifndef _LINUX_ATOMIC_H #define _LINUX_ATOMIC_H #include <asm/atomic.h> +#include <asm/barrier.h> + +/* + * Relaxed variants of xchg, cmpxchg and some atomic operations. + * + * We support four variants: + * + * - Fully ordered: The default implementation, no suffix required. + * - Acquire: Provides ACQUIRE semantics, _acquire suffix. + * - Release: Provides RELEASE semantics, _release suffix. + * - Relaxed: No ordering guarantees, _relaxed suffix. + * + * For compound atomics performing both a load and a store, ACQUIRE + * semantics apply only to the load and RELEASE semantics only to the + * store portion of the operation. Note that a failed cmpxchg_acquire + * does -not- imply any memory ordering constraints. + * + * See Documentation/memory-barriers.txt for ACQUIRE/RELEASE definitions. + */ + +#ifndef atomic_read_acquire +#define atomic_read_acquire(v) smp_load_acquire(&(v)->counter) +#endif + +#ifndef atomic_set_release +#define atomic_set_release(v, i) smp_store_release(&(v)->counter, (i)) +#endif + +/* + * The idea here is to build acquire/release variants by adding explicit + * barriers on top of the relaxed variant. In the case where the relaxed + * variant is already fully ordered, no additional barriers are needed. + */ +#define __atomic_op_acquire(op, args...) \ +({ \ + typeof(op##_relaxed(args)) __ret = op##_relaxed(args); \ + smp_mb__after_atomic(); \ + __ret; \ +}) + +#define __atomic_op_release(op, args...) \ +({ \ + smp_mb__before_atomic(); \ + op##_relaxed(args); \ +}) + +#define __atomic_op_fence(op, args...) \ +({ \ + typeof(op##_relaxed(args)) __ret; \ + smp_mb__before_atomic(); \ + __ret = op##_relaxed(args); \ + smp_mb__after_atomic(); \ + __ret; \ +}) + +/* atomic_add_return_relaxed */ +#ifndef atomic_add_return_relaxed +#define atomic_add_return_relaxed atomic_add_return +#define atomic_add_return_acquire atomic_add_return +#define atomic_add_return_release atomic_add_return + +#else /* atomic_add_return_relaxed */ + +#ifndef atomic_add_return_acquire +#define atomic_add_return_acquire(...) \ + __atomic_op_acquire(atomic_add_return, __VA_ARGS__) +#endif + +#ifndef atomic_add_return_release +#define atomic_add_return_release(...) \ + __atomic_op_release(atomic_add_return, __VA_ARGS__) +#endif + +#ifndef atomic_add_return +#define atomic_add_return(...) \ + __atomic_op_fence(atomic_add_return, __VA_ARGS__) +#endif +#endif /* atomic_add_return_relaxed */ + +/* atomic_sub_return_relaxed */ +#ifndef atomic_sub_return_relaxed +#define atomic_sub_return_relaxed atomic_sub_return +#define atomic_sub_return_acquire atomic_sub_return +#define atomic_sub_return_release atomic_sub_return + +#else /* atomic_sub_return_relaxed */ + +#ifndef atomic_sub_return_acquire +#define atomic_sub_return_acquire(...) \ + __atomic_op_acquire(atomic_sub_return, __VA_ARGS__) +#endif + +#ifndef atomic_sub_return_release +#define atomic_sub_return_release(...) \ + __atomic_op_release(atomic_sub_return, __VA_ARGS__) +#endif + +#ifndef atomic_sub_return +#define atomic_sub_return(...) \ + __atomic_op_fence(atomic_sub_return, __VA_ARGS__) +#endif +#endif /* atomic_sub_return_relaxed */ + +/* atomic_xchg_relaxed */ +#ifndef atomic_xchg_relaxed +#define atomic_xchg_relaxed atomic_xchg +#define atomic_xchg_acquire atomic_xchg +#define atomic_xchg_release atomic_xchg + +#else /* atomic_xchg_relaxed */ + +#ifndef atomic_xchg_acquire +#define atomic_xchg_acquire(...) \ + __atomic_op_acquire(atomic_xchg, __VA_ARGS__) +#endif + +#ifndef atomic_xchg_release +#define atomic_xchg_release(...) \ + __atomic_op_release(atomic_xchg, __VA_ARGS__) +#endif + +#ifndef atomic_xchg +#define atomic_xchg(...) \ + __atomic_op_fence(atomic_xchg, __VA_ARGS__) +#endif +#endif /* atomic_xchg_relaxed */ + +/* atomic_cmpxchg_relaxed */ +#ifndef atomic_cmpxchg_relaxed +#define atomic_cmpxchg_relaxed atomic_cmpxchg +#define atomic_cmpxchg_acquire atomic_cmpxchg +#define atomic_cmpxchg_release atomic_cmpxchg + +#else /* atomic_cmpxchg_relaxed */ + +#ifndef atomic_cmpxchg_acquire +#define atomic_cmpxchg_acquire(...) \ + __atomic_op_acquire(atomic_cmpxchg, __VA_ARGS__) +#endif + +#ifndef atomic_cmpxchg_release +#define atomic_cmpxchg_release(...) \ + __atomic_op_release(atomic_cmpxchg, __VA_ARGS__) +#endif + +#ifndef atomic_cmpxchg +#define atomic_cmpxchg(...) \ + __atomic_op_fence(atomic_cmpxchg, __VA_ARGS__) +#endif +#endif /* atomic_cmpxchg_relaxed */ + +#ifndef atomic64_read_acquire +#define atomic64_read_acquire(v) smp_load_acquire(&(v)->counter) +#endif + +#ifndef atomic64_set_release +#define atomic64_set_release(v, i) smp_store_release(&(v)->counter, (i)) +#endif + +/* atomic64_add_return_relaxed */ +#ifndef atomic64_add_return_relaxed +#define atomic64_add_return_relaxed atomic64_add_return +#define atomic64_add_return_acquire atomic64_add_return +#define atomic64_add_return_release atomic64_add_return + +#else /* atomic64_add_return_relaxed */ + +#ifndef atomic64_add_return_acquire +#define atomic64_add_return_acquire(...) \ + __atomic_op_acquire(atomic64_add_return, __VA_ARGS__) +#endif + +#ifndef atomic64_add_return_release +#define atomic64_add_return_release(...) \ + __atomic_op_release(atomic64_add_return, __VA_ARGS__) +#endif + +#ifndef atomic64_add_return +#define atomic64_add_return(...) \ + __atomic_op_fence(atomic64_add_return, __VA_ARGS__) +#endif +#endif /* atomic64_add_return_relaxed */ + +/* atomic64_sub_return_relaxed */ +#ifndef atomic64_sub_return_relaxed +#define atomic64_sub_return_relaxed atomic64_sub_return +#define atomic64_sub_return_acquire atomic64_sub_return +#define atomic64_sub_return_release atomic64_sub_return + +#else /* atomic64_sub_return_relaxed */ + +#ifndef atomic64_sub_return_acquire +#define atomic64_sub_return_acquire(...) \ + __atomic_op_acquire(atomic64_sub_return, __VA_ARGS__) +#endif + +#ifndef atomic64_sub_return_release +#define atomic64_sub_return_release(...) \ + __atomic_op_release(atomic64_sub_return, __VA_ARGS__) +#endif + +#ifndef atomic64_sub_return +#define atomic64_sub_return(...) \ + __atomic_op_fence(atomic64_sub_return, __VA_ARGS__) +#endif +#endif /* atomic64_sub_return_relaxed */ + +/* atomic64_xchg_relaxed */ +#ifndef atomic64_xchg_relaxed +#define atomic64_xchg_relaxed atomic64_xchg +#define atomic64_xchg_acquire atomic64_xchg +#define atomic64_xchg_release atomic64_xchg + +#else /* atomic64_xchg_relaxed */ + +#ifndef atomic64_xchg_acquire +#define atomic64_xchg_acquire(...) \ + __atomic_op_acquire(atomic64_xchg, __VA_ARGS__) +#endif + +#ifndef atomic64_xchg_release +#define atomic64_xchg_release(...) \ + __atomic_op_release(atomic64_xchg, __VA_ARGS__) +#endif + +#ifndef atomic64_xchg +#define atomic64_xchg(...) \ + __atomic_op_fence(atomic64_xchg, __VA_ARGS__) +#endif +#endif /* atomic64_xchg_relaxed */ + +/* atomic64_cmpxchg_relaxed */ +#ifndef atomic64_cmpxchg_relaxed +#define atomic64_cmpxchg_relaxed atomic64_cmpxchg +#define atomic64_cmpxchg_acquire atomic64_cmpxchg +#define atomic64_cmpxchg_release atomic64_cmpxchg + +#else /* atomic64_cmpxchg_relaxed */ + +#ifndef atomic64_cmpxchg_acquire +#define atomic64_cmpxchg_acquire(...) \ + __atomic_op_acquire(atomic64_cmpxchg, __VA_ARGS__) +#endif + +#ifndef atomic64_cmpxchg_release +#define atomic64_cmpxchg_release(...) \ + __atomic_op_release(atomic64_cmpxchg, __VA_ARGS__) +#endif + +#ifndef atomic64_cmpxchg +#define atomic64_cmpxchg(...) \ + __atomic_op_fence(atomic64_cmpxchg, __VA_ARGS__) +#endif +#endif /* atomic64_cmpxchg_relaxed */ + +/* cmpxchg_relaxed */ +#ifndef cmpxchg_relaxed +#define cmpxchg_relaxed cmpxchg +#define cmpxchg_acquire cmpxchg +#define cmpxchg_release cmpxchg + +#else /* cmpxchg_relaxed */ + +#ifndef cmpxchg_acquire +#define cmpxchg_acquire(...) \ + __atomic_op_acquire(cmpxchg, __VA_ARGS__) +#endif + +#ifndef cmpxchg_release +#define cmpxchg_release(...) \ + __atomic_op_release(cmpxchg, __VA_ARGS__) +#endif + +#ifndef cmpxchg +#define cmpxchg(...) \ + __atomic_op_fence(cmpxchg, __VA_ARGS__) +#endif +#endif /* cmpxchg_relaxed */ + +/* cmpxchg64_relaxed */ +#ifndef cmpxchg64_relaxed +#define cmpxchg64_relaxed cmpxchg64 +#define cmpxchg64_acquire cmpxchg64 +#define cmpxchg64_release cmpxchg64 + +#else /* cmpxchg64_relaxed */ + +#ifndef cmpxchg64_acquire +#define cmpxchg64_acquire(...) \ + __atomic_op_acquire(cmpxchg64, __VA_ARGS__) +#endif + +#ifndef cmpxchg64_release +#define cmpxchg64_release(...) \ + __atomic_op_release(cmpxchg64, __VA_ARGS__) +#endif + +#ifndef cmpxchg64 +#define cmpxchg64(...) \ + __atomic_op_fence(cmpxchg64, __VA_ARGS__) +#endif +#endif /* cmpxchg64_relaxed */ + +/* xchg_relaxed */ +#ifndef xchg_relaxed +#define xchg_relaxed xchg +#define xchg_acquire xchg +#define xchg_release xchg + +#else /* xchg_relaxed */ + +#ifndef xchg_acquire +#define xchg_acquire(...) __atomic_op_acquire(xchg, __VA_ARGS__) +#endif + +#ifndef xchg_release +#define xchg_release(...) __atomic_op_release(xchg, __VA_ARGS__) +#endif + +#ifndef xchg +#define xchg(...) __atomic_op_fence(xchg, __VA_ARGS__) +#endif +#endif /* xchg_relaxed */ /** * atomic_add_unless - add unless the number is already a given value @@ -28,6 +351,23 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u) #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) #endif +#ifndef atomic_andnot +static inline void atomic_andnot(int i, atomic_t *v) +{ + atomic_and(~i, v); +} +#endif + +static inline __deprecated void atomic_clear_mask(unsigned int mask, atomic_t *v) +{ + atomic_andnot(mask, v); +} + +static inline __deprecated void atomic_set_mask(unsigned int mask, atomic_t *v) +{ + atomic_or(mask, v); +} + /** * atomic_inc_not_zero_hint - increment if not null * @v: pointer of type atomic_t @@ -111,21 +451,16 @@ static inline int atomic_dec_if_positive(atomic_t *v) } #endif -#ifndef CONFIG_ARCH_HAS_ATOMIC_OR -static inline void atomic_or(int i, atomic_t *v) -{ - int old; - int new; - - do { - old = atomic_read(v); - new = old | i; - } while (atomic_cmpxchg(v, old, new) != old); -} -#endif /* #ifndef CONFIG_ARCH_HAS_ATOMIC_OR */ - #include <asm-generic/atomic-long.h> #ifdef CONFIG_GENERIC_ATOMIC64 #include <asm-generic/atomic64.h> #endif + +#ifndef atomic64_andnot +static inline void atomic64_andnot(long long i, atomic64_t *v) +{ + atomic64_and(~i, v); +} +#endif + #endif /* _LINUX_ATOMIC_H */ diff --git a/include/linux/compiler.h b/include/linux/compiler.h index e08a6ae7c0a4..c836eb2dc44d 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -252,7 +252,12 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s ({ union { typeof(x) __val; char __c[1]; } __u; __read_once_size(&(x), __u.__c, sizeof(x)); __u.__val; }) #define WRITE_ONCE(x, val) \ - ({ union { typeof(x) __val; char __c[1]; } __u = { .__val = (val) }; __write_once_size(&(x), __u.__c, sizeof(x)); __u.__val; }) +({ \ + union { typeof(x) __val; char __c[1]; } __u = \ + { .__val = (__force typeof(x)) (val) }; \ + __write_once_size(&(x), __u.__c, sizeof(x)); \ + __u.__val; \ +}) /** * READ_ONCE_CTRL - Read a value heading a control dependency diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index f4de473f226b..7f653e8f6690 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -7,17 +7,52 @@ * Copyright (C) 2009-2012 Jason Baron <jbaron@redhat.com> * Copyright (C) 2011-2012 Peter Zijlstra <pzijlstr@redhat.com> * + * DEPRECATED API: + * + * The use of 'struct static_key' directly, is now DEPRECATED. In addition + * static_key_{true,false}() is also DEPRECATED. IE DO NOT use the following: + * + * struct static_key false = STATIC_KEY_INIT_FALSE; + * struct static_key true = STATIC_KEY_INIT_TRUE; + * static_key_true() + * static_key_false() + * + * The updated API replacements are: + * + * DEFINE_STATIC_KEY_TRUE(key); + * DEFINE_STATIC_KEY_FALSE(key); + * static_key_likely() + * statick_key_unlikely() + * * Jump labels provide an interface to generate dynamic branches using - * self-modifying code. Assuming toolchain and architecture support, the result - * of a "if (static_key_false(&key))" statement is an unconditional branch (which - * defaults to false - and the true block is placed out of line). + * self-modifying code. Assuming toolchain and architecture support, if we + * define a "key" that is initially false via "DEFINE_STATIC_KEY_FALSE(key)", + * an "if (static_branch_unlikely(&key))" statement is an unconditional branch + * (which defaults to false - and the true block is placed out of line). + * Similarly, we can define an initially true key via + * "DEFINE_STATIC_KEY_TRUE(key)", and use it in the same + * "if (static_branch_unlikely(&key))", in which case we will generate an + * unconditional branch to the out-of-line true branch. Keys that are + * initially true or false can be using in both static_branch_unlikely() + * and static_branch_likely() statements. + * + * At runtime we can change the branch target by setting the key + * to true via a call to static_branch_enable(), or false using + * static_branch_disable(). If the direction of the branch is switched by + * these calls then we run-time modify the branch target via a + * no-op -> jump or jump -> no-op conversion. For example, for an + * initially false key that is used in an "if (static_branch_unlikely(&key))" + * statement, setting the key to true requires us to patch in a jump + * to the out-of-line of true branch. * - * However at runtime we can change the branch target using - * static_key_slow_{inc,dec}(). These function as a 'reference' count on the key - * object, and for as long as there are references all branches referring to - * that particular key will point to the (out of line) true block. + * In addtion to static_branch_{enable,disable}, we can also reference count + * the key or branch direction via static_branch_{inc,dec}. Thus, + * static_branch_inc() can be thought of as a 'make more true' and + * static_branch_dec() as a 'make more false'. The inc()/dec() + * interface is meant to be used exclusively from the inc()/dec() for a given + * key. * - * Since this relies on modifying code, the static_key_slow_{inc,dec}() functions + * Since this relies on modifying code, the branch modifying functions * must be considered absolute slow paths (machine wide synchronization etc.). * OTOH, since the affected branches are unconditional, their runtime overhead * will be absolutely minimal, esp. in the default (off) case where the total @@ -29,20 +64,10 @@ * cause significant performance degradation. Struct static_key_deferred and * static_key_slow_dec_deferred() provide for this. * - * Lacking toolchain and or architecture support, jump labels fall back to a simple - * conditional branch. - * - * struct static_key my_key = STATIC_KEY_INIT_TRUE; - * - * if (static_key_true(&my_key)) { - * } + * Lacking toolchain and or architecture support, static keys fall back to a + * simple conditional branch. * - * will result in the true case being in-line and starts the key with a single - * reference. Mixing static_key_true() and static_key_false() on the same key is not - * allowed. - * - * Not initializing the key (static data is initialized to 0s anyway) is the - * same as using STATIC_KEY_INIT_FALSE. + * Additional babbling in: Documentation/static-keys.txt */ #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) @@ -86,8 +111,8 @@ struct static_key { #ifndef __ASSEMBLY__ enum jump_label_type { - JUMP_LABEL_DISABLE = 0, - JUMP_LABEL_ENABLE, + JUMP_LABEL_NOP = 0, + JUMP_LABEL_JMP, }; struct module; @@ -101,33 +126,18 @@ static inline int static_key_count(struct static_key *key) #ifdef HAVE_JUMP_LABEL -#define JUMP_LABEL_TYPE_FALSE_BRANCH 0UL -#define JUMP_LABEL_TYPE_TRUE_BRANCH 1UL -#define JUMP_LABEL_TYPE_MASK 1UL - -static -inline struct jump_entry *jump_label_get_entries(struct static_key *key) -{ - return (struct jump_entry *)((unsigned long)key->entries - & ~JUMP_LABEL_TYPE_MASK); -} - -static inline bool jump_label_get_branch_default(struct static_key *key) -{ - if (((unsigned long)key->entries & JUMP_LABEL_TYPE_MASK) == - JUMP_LABEL_TYPE_TRUE_BRANCH) - return true; - return false; -} +#define JUMP_TYPE_FALSE 0UL +#define JUMP_TYPE_TRUE 1UL +#define JUMP_TYPE_MASK 1UL static __always_inline bool static_key_false(struct static_key *key) { - return arch_static_branch(key); + return arch_static_branch(key, false); } static __always_inline bool static_key_true(struct static_key *key) { - return !static_key_false(key); + return !arch_static_branch(key, true); } extern struct jump_entry __start___jump_table[]; @@ -145,12 +155,12 @@ extern void static_key_slow_inc(struct static_key *key); extern void static_key_slow_dec(struct static_key *key); extern void jump_label_apply_nops(struct module *mod); -#define STATIC_KEY_INIT_TRUE ((struct static_key) \ +#define STATIC_KEY_INIT_TRUE \ { .enabled = ATOMIC_INIT(1), \ - .entries = (void *)JUMP_LABEL_TYPE_TRUE_BRANCH }) -#define STATIC_KEY_INIT_FALSE ((struct static_key) \ + .entries = (void *)JUMP_TYPE_TRUE } +#define STATIC_KEY_INIT_FALSE \ { .enabled = ATOMIC_INIT(0), \ - .entries = (void *)JUMP_LABEL_TYPE_FALSE_BRANCH }) + .entries = (void *)JUMP_TYPE_FALSE } #else /* !HAVE_JUMP_LABEL */ @@ -198,10 +208,8 @@ static inline int jump_label_apply_nops(struct module *mod) return 0; } -#define STATIC_KEY_INIT_TRUE ((struct static_key) \ - { .enabled = ATOMIC_INIT(1) }) -#define STATIC_KEY_INIT_FALSE ((struct static_key) \ - { .enabled = ATOMIC_INIT(0) }) +#define STATIC_KEY_INIT_TRUE { .enabled = ATOMIC_INIT(1) } +#define STATIC_KEY_INIT_FALSE { .enabled = ATOMIC_INIT(0) } #endif /* HAVE_JUMP_LABEL */ @@ -213,6 +221,157 @@ static inline bool static_key_enabled(struct static_key *key) return static_key_count(key) > 0; } +static inline void static_key_enable(struct static_key *key) +{ + int count = static_key_count(key); + + WARN_ON_ONCE(count < 0 || count > 1); + + if (!count) + static_key_slow_inc(key); +} + +static inline void static_key_disable(struct static_key *key) +{ + int count = static_key_count(key); + + WARN_ON_ONCE(count < 0 || count > 1); + + if (count) + static_key_slow_dec(key); +} + +/* -------------------------------------------------------------------------- */ + +/* + * Two type wrappers around static_key, such that we can use compile time + * type differentiation to emit the right code. + * + * All the below code is macros in order to play type games. + */ + +struct static_key_true { + struct static_key key; +}; + +struct static_key_false { + struct static_key key; +}; + +#define STATIC_KEY_TRUE_INIT (struct static_key_true) { .key = STATIC_KEY_INIT_TRUE, } +#define STATIC_KEY_FALSE_INIT (struct static_key_false){ .key = STATIC_KEY_INIT_FALSE, } + +#define DEFINE_STATIC_KEY_TRUE(name) \ + struct static_key_true name = STATIC_KEY_TRUE_INIT + +#define DEFINE_STATIC_KEY_FALSE(name) \ + struct static_key_false name = STATIC_KEY_FALSE_INIT + +#ifdef HAVE_JUMP_LABEL + +/* + * Combine the right initial value (type) with the right branch order + * to generate the desired result. + * + * + * type\branch| likely (1) | unlikely (0) + * -----------+-----------------------+------------------ + * | | + * true (1) | ... | ... + * | NOP | JMP L + * | <br-stmts> | 1: ... + * | L: ... | + * | | + * | | L: <br-stmts> + * | | jmp 1b + * | | + * -----------+-----------------------+------------------ + * | | + * false (0) | ... | ... + * | JMP L | NOP + * | <br-stmts> | 1: ... + * | L: ... | + * | | + * | | L: <br-stmts> + * | | jmp 1b + * | | + * -----------+-----------------------+------------------ + * + * The initial value is encoded in the LSB of static_key::entries, + * type: 0 = false, 1 = true. + * + * The branch type is encoded in the LSB of jump_entry::key, + * branch: 0 = unlikely, 1 = likely. + * + * This gives the following logic table: + * + * enabled type branch instuction + * -----------------------------+----------- + * 0 0 0 | NOP + * 0 0 1 | JMP + * 0 1 0 | NOP + * 0 1 1 | JMP + * + * 1 0 0 | JMP + * 1 0 1 | NOP + * 1 1 0 | JMP + * 1 1 1 | NOP + * + * Which gives the following functions: + * + * dynamic: instruction = enabled ^ branch + * static: instruction = type ^ branch + * + * See jump_label_type() / jump_label_init_type(). + */ + +extern bool ____wrong_branch_error(void); + +#define static_branch_likely(x) \ +({ \ + bool branch; \ + if (__builtin_types_compatible_p(typeof(*x), struct static_key_true)) \ + branch = !arch_static_branch(&(x)->key, true); \ + else if (__builtin_types_compatible_p(typeof(*x), struct static_key_false)) \ + branch = !arch_static_branch_jump(&(x)->key, true); \ + else \ + branch = ____wrong_branch_error(); \ + branch; \ +}) + +#define static_branch_unlikely(x) \ +({ \ + bool branch; \ + if (__builtin_types_compatible_p(typeof(*x), struct static_key_true)) \ + branch = arch_static_branch_jump(&(x)->key, false); \ + else if (__builtin_types_compatible_p(typeof(*x), struct static_key_false)) \ + branch = arch_static_branch(&(x)->key, false); \ + else \ + branch = ____wrong_branch_error(); \ + branch; \ +}) + +#else /* !HAVE_JUMP_LABEL */ + +#define static_branch_likely(x) likely(static_key_enabled(&(x)->key)) +#define static_branch_unlikely(x) unlikely(static_key_enabled(&(x)->key)) + +#endif /* HAVE_JUMP_LABEL */ + +/* + * Advanced usage; refcount, branch is enabled when: count != 0 + */ + +#define static_branch_inc(x) static_key_slow_inc(&(x)->key) +#define static_branch_dec(x) static_key_slow_dec(&(x)->key) + +/* + * Normal usage; boolean enable/disable. + */ + +#define static_branch_enable(x) static_key_enable(&(x)->key) +#define static_branch_disable(x) static_key_disable(&(x)->key) + #endif /* _LINUX_JUMP_LABEL_H */ #endif /* __ASSEMBLY__ */ diff --git a/include/linux/llist.h b/include/linux/llist.h index fbf10a0bc095..fd4ca0b4fe0f 100644 --- a/include/linux/llist.h +++ b/include/linux/llist.h @@ -55,8 +55,8 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ +#include <linux/atomic.h> #include <linux/kernel.h> -#include <asm/cmpxchg.h> struct llist_head { struct llist_node *first; |