76 lines
2.4 KiB
C
76 lines
2.4 KiB
C
|
/*
|
||
|
|
* Copyright (c) Facebook, Inc. and its affiliates.
|
||
|
|
*
|
||
|
|
* 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.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#pragma once
|
||
|
|
|
||
|
|
#include <atomic>
|
||
|
|
|
||
|
|
#include <folly/Portability.h>
|
||
|
|
|
||
|
|
namespace folly {
|
||
|
|
|
||
|
|
// Valid status values returned from rtmBegin.
|
||
|
|
// kRtmDisabled is a new return value indicating that RTM support is unavailable
|
||
|
|
// on the platform or the compiler.
|
||
|
|
constexpr unsigned kRtmDisabled = static_cast<unsigned>(-2);
|
||
|
|
constexpr unsigned kRtmBeginStarted = static_cast<unsigned>(-1);
|
||
|
|
|
||
|
|
// Valid abort status bits (when the status value is not kRtmBeginStarted or
|
||
|
|
// kRtmDisabled), defined as per the Intel RTM specifications:
|
||
|
|
// https://en.wikipedia.org/wiki/Transactional_Synchronization_Extensions.
|
||
|
|
constexpr unsigned kRtmAbortExplicit = 1;
|
||
|
|
constexpr unsigned kRtmAbortRetry = 2;
|
||
|
|
constexpr unsigned kRtmAbortConflict = 4;
|
||
|
|
constexpr unsigned kRtmAbortCapacity = 8;
|
||
|
|
constexpr unsigned kRtmAbortDebug = 16;
|
||
|
|
constexpr unsigned kRtmAbortNested = 32;
|
||
|
|
|
||
|
|
// False if there is no need for a dynamic check to see if
|
||
|
|
// the current environment supports RTM
|
||
|
|
constexpr bool kRtmSupportEnabled = kIsArchAmd64;
|
||
|
|
|
||
|
|
// Check on cpu support for tsx-rtm
|
||
|
|
extern bool rtmEnabled();
|
||
|
|
|
||
|
|
namespace detail {
|
||
|
|
|
||
|
|
// Use func ptrs to access the txn functions to avoid txn aborts
|
||
|
|
// due to plt mapping.
|
||
|
|
extern std::atomic<unsigned (*)()> rtmBeginV;
|
||
|
|
extern std::atomic<void (*)()> rtmEndV;
|
||
|
|
extern std::atomic<bool (*)()> rtmTestV;
|
||
|
|
extern std::atomic<void (*)(uint8_t)> rtmAbortV;
|
||
|
|
|
||
|
|
} // namespace detail
|
||
|
|
|
||
|
|
inline unsigned rtmBegin() {
|
||
|
|
return detail::rtmBeginV.load(std::memory_order_relaxed)();
|
||
|
|
}
|
||
|
|
inline void rtmEnd() {
|
||
|
|
return detail::rtmEndV.load(std::memory_order_relaxed)();
|
||
|
|
}
|
||
|
|
inline bool rtmTest() {
|
||
|
|
return detail::rtmTestV.load(std::memory_order_relaxed)();
|
||
|
|
}
|
||
|
|
inline void rtmAbort(uint8_t status) {
|
||
|
|
return detail::rtmAbortV.load(std::memory_order_relaxed)(status);
|
||
|
|
}
|
||
|
|
inline uint8_t rtmStatusToAbortCode(unsigned status) {
|
||
|
|
return status >> 24;
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace folly
|