legacy-libs/grpc/deps/grpc/include/grpc/impl/codegen/atm_gcc_atomic.h

   1 /*
   2  *
   3  * Copyright 2015 gRPC authors.
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  *
  17  */
  18
  19 #ifndef GRPC_IMPL_CODEGEN_ATM_GCC_ATOMIC_H
  20 #define GRPC_IMPL_CODEGEN_ATM_GCC_ATOMIC_H
  21
  22 /* atm_platform.h for gcc and gcc-like compilers with the
  23    __atomic_* interface.  */
  24 #include <grpc/impl/codegen/port_platform.h>
  25
  26 #ifdef __cplusplus
  27 extern "C" {
  28 #endif
  29
  30 typedef intptr_t gpr_atm;
  31 #define GPR_ATM_MAX INTPTR_MAX
  32 #define GPR_ATM_MIN INTPTR_MIN
  33
  34 #ifdef GPR_LOW_LEVEL_COUNTERS
  35 extern gpr_atm gpr_counter_atm_cas;
  36 extern gpr_atm gpr_counter_atm_add;
  37 #define GPR_ATM_INC_COUNTER(counter) \
  38   __atomic_fetch_add(&counter, 1, __ATOMIC_RELAXED)
  39 #define GPR_ATM_INC_CAS_THEN(blah) \
  40   (GPR_ATM_INC_COUNTER(gpr_counter_atm_cas), blah)
  41 #define GPR_ATM_INC_ADD_THEN(blah) \
  42   (GPR_ATM_INC_COUNTER(gpr_counter_atm_add), blah)
  43 #else
  44 #define GPR_ATM_INC_CAS_THEN(blah) blah
  45 #define GPR_ATM_INC_ADD_THEN(blah) blah
  46 #endif
  47
  48 #define gpr_atm_full_barrier() (__atomic_thread_fence(__ATOMIC_SEQ_CST))
  49
  50 #define gpr_atm_acq_load(p) (__atomic_load_n((p), __ATOMIC_ACQUIRE))
  51 #define gpr_atm_no_barrier_load(p) (__atomic_load_n((p), __ATOMIC_RELAXED))
  52 #define gpr_atm_rel_store(p, value) \
  53   (__atomic_store_n((p), (intptr_t)(value), __ATOMIC_RELEASE))
  54 #define gpr_atm_no_barrier_store(p, value) \
  55   (__atomic_store_n((p), (intptr_t)(value), __ATOMIC_RELAXED))
  56
  57 #define gpr_atm_no_barrier_fetch_add(p, delta) \
  58   GPR_ATM_INC_ADD_THEN(                        \
  59       __atomic_fetch_add((p), (intptr_t)(delta), __ATOMIC_RELAXED))
  60 #define gpr_atm_full_fetch_add(p, delta) \
  61   GPR_ATM_INC_ADD_THEN(                  \
  62       __atomic_fetch_add((p), (intptr_t)(delta), __ATOMIC_ACQ_REL))
  63
  64 static __inline int gpr_atm_no_barrier_cas(gpr_atm* p, gpr_atm o, gpr_atm n) {
  65   return GPR_ATM_INC_CAS_THEN(__atomic_compare_exchange_n(
  66       p, &o, n, 0, __ATOMIC_RELAXED, __ATOMIC_RELAXED));
  67 }
  68
  69 static __inline int gpr_atm_acq_cas(gpr_atm* p, gpr_atm o, gpr_atm n) {
  70   return GPR_ATM_INC_CAS_THEN(__atomic_compare_exchange_n(
  71       p, &o, n, 0, __ATOMIC_ACQUIRE, __ATOMIC_RELAXED));
  72 }
  73
  74 static __inline int gpr_atm_rel_cas(gpr_atm* p, gpr_atm o, gpr_atm n) {
  75   return GPR_ATM_INC_CAS_THEN(__atomic_compare_exchange_n(
  76       p, &o, n, 0, __ATOMIC_RELEASE, __ATOMIC_RELAXED));
  77 }
  78
  79 static __inline int gpr_atm_full_cas(gpr_atm* p, gpr_atm o, gpr_atm n) {
  80   return GPR_ATM_INC_CAS_THEN(__atomic_compare_exchange_n(
  81       p, &o, n, 0, __ATOMIC_ACQ_REL, __ATOMIC_RELAXED));
  82 }
  83
  84 #define gpr_atm_full_xchg(p, n) \
  85   GPR_ATM_INC_CAS_THEN(__atomic_exchange_n((p), (n), __ATOMIC_ACQ_REL))
  86
  87 #ifdef __cplusplus
  88 }
  89 #endif
  90
  91 #endif /* GRPC_IMPL_CODEGEN_ATM_GCC_ATOMIC_H */