| /* |
| * |
| * Copyright 2015 gRPC authors. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| */ |
| |
| #ifndef GRPC_CORE_LIB_GPR_SPINLOCK_H |
| #define GRPC_CORE_LIB_GPR_SPINLOCK_H |
| |
| #include <grpc/support/port_platform.h> |
| |
| #include <grpc/support/atm.h> |
| |
| /* Simple spinlock. No backoff strategy, gpr_spinlock_lock is almost always |
| a concurrency code smell. */ |
| typedef struct { |
| gpr_atm atm; |
| } gpr_spinlock; |
| |
| #ifdef __cplusplus |
| #define GPR_SPINLOCK_INITIALIZER (gpr_spinlock{0}) |
| #else |
| #define GPR_SPINLOCK_INITIALIZER ((gpr_spinlock){0}) |
| #endif |
| #define GPR_SPINLOCK_STATIC_INITIALIZER \ |
| { 0 } |
| |
| #define gpr_spinlock_trylock(lock) (gpr_atm_acq_cas(&(lock)->atm, 0, 1)) |
| #define gpr_spinlock_unlock(lock) (gpr_atm_rel_store(&(lock)->atm, 0)) |
| #define gpr_spinlock_lock(lock) \ |
| do { \ |
| } while (!gpr_spinlock_trylock((lock))) |
| |
| #endif /* GRPC_CORE_LIB_GPR_SPINLOCK_H */ |