3 * Copyright 2015 gRPC authors.
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
9 * http://www.apache.org/licenses/LICENSE-2.0
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.
19 #ifndef GRPC_IMPL_CODEGEN_ATM_GCC_SYNC_H
20 #define GRPC_IMPL_CODEGEN_ATM_GCC_SYNC_H
22 /* variant of atm_platform.h for gcc and gcc-like compiers with __sync_*
24 #include <grpc/impl/codegen/port_platform.h>
26 typedef intptr_t gpr_atm;
27 #define GPR_ATM_MAX INTPTR_MAX
28 #define GPR_ATM_MIN INTPTR_MIN
29 #define GPR_ATM_INC_CAS_THEN(blah) blah
30 #define GPR_ATM_INC_ADD_THEN(blah) blah
32 #define GPR_ATM_COMPILE_BARRIER_() __asm__ __volatile__("" : : : "memory")
34 #if defined(__i386) || defined(__x86_64__)
35 /* All loads are acquire loads and all stores are release stores. */
36 #define GPR_ATM_LS_BARRIER_() GPR_ATM_COMPILE_BARRIER_()
38 #define GPR_ATM_LS_BARRIER_() gpr_atm_full_barrier()
41 #define gpr_atm_full_barrier() (__sync_synchronize())
43 static __inline gpr_atm gpr_atm_acq_load(const gpr_atm* p) {
45 GPR_ATM_LS_BARRIER_();
49 static __inline gpr_atm gpr_atm_no_barrier_load(const gpr_atm* p) {
51 GPR_ATM_COMPILE_BARRIER_();
55 static __inline void gpr_atm_rel_store(gpr_atm* p, gpr_atm value) {
56 GPR_ATM_LS_BARRIER_();
60 static __inline void gpr_atm_no_barrier_store(gpr_atm* p, gpr_atm value) {
61 GPR_ATM_COMPILE_BARRIER_();
65 #undef GPR_ATM_LS_BARRIER_
66 #undef GPR_ATM_COMPILE_BARRIER_
68 #define gpr_atm_no_barrier_fetch_add(p, delta) \
69 gpr_atm_full_fetch_add((p), (delta))
70 #define gpr_atm_full_fetch_add(p, delta) (__sync_fetch_and_add((p), (delta)))
72 #define gpr_atm_no_barrier_cas(p, o, n) gpr_atm_acq_cas((p), (o), (n))
73 #define gpr_atm_acq_cas(p, o, n) (__sync_bool_compare_and_swap((p), (o), (n)))
74 #define gpr_atm_rel_cas(p, o, n) gpr_atm_acq_cas((p), (o), (n))
75 #define gpr_atm_full_cas(p, o, n) gpr_atm_acq_cas((p), (o), (n))
77 static __inline gpr_atm gpr_atm_full_xchg(gpr_atm* p, gpr_atm n) {
80 cur = gpr_atm_acq_load(p);
81 } while (!gpr_atm_rel_cas(p, cur, n));
85 #endif /* GRPC_IMPL_CODEGEN_ATM_GCC_SYNC_H */