fe6f137e48
DeviceTy provides an abstraction for "middle-level" operations that can be done with a offload device. Mapping was tied into it but is not strictly necessary. Other languages do not track mapping, and even OpenMP can be used completely without mapping. This simply moves the relevant code into the OpenMP/Mapping.cpp as part of a new class MappingInfoTy. Each device still has one, but it does not clutter the device.cpp anymore.
102 lines
3.0 KiB
C++
102 lines
3.0 KiB
C++
//===---- ExclusiveAccess.h - Helper for exclusive access data structures -===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef OMPTARGET_EXCLUSIVE_ACCESS
|
|
#define OMPTARGET_EXCLUSIVE_ACCESS
|
|
|
|
#include <cassert>
|
|
#include <cstddef>
|
|
#include <cstdint>
|
|
#include <mutex>
|
|
|
|
/// Forward declaration.
|
|
template <typename Ty> struct Accessor;
|
|
|
|
/// A protected object is a simple wrapper to allocate an object of type \p Ty
|
|
/// together with a mutex that guards accesses to the object. The only way to
|
|
/// access the object is through the "exclusive accessor" which will lock the
|
|
/// mutex accordingly.
|
|
template <typename Ty> struct ProtectedObj {
|
|
using AccessorTy = Accessor<Ty>;
|
|
|
|
/// Get an exclusive access Accessor object. \p DoNotGetAccess allows to
|
|
/// create an accessor that is not owning anything based on a boolean
|
|
/// condition.
|
|
AccessorTy getExclusiveAccessor(bool DoNotGetAccess = false);
|
|
|
|
private:
|
|
Ty Obj;
|
|
std::mutex Mtx;
|
|
friend struct Accessor<Ty>;
|
|
};
|
|
|
|
/// Helper to provide transparent exclusive access to protected objects.
|
|
template <typename Ty> struct Accessor {
|
|
/// Default constructor does not own anything and cannot access anything.
|
|
Accessor() : Ptr(nullptr) {}
|
|
|
|
/// Constructor to get exclusive access by locking the mutex protecting the
|
|
/// underlying object.
|
|
Accessor(ProtectedObj<Ty> &PO) : Ptr(&PO) { lock(); }
|
|
|
|
/// Constructor to get exclusive access by taking it from \p Other.
|
|
Accessor(Accessor<Ty> &&Other) : Ptr(Other.Ptr) { Other.Ptr = nullptr; }
|
|
|
|
Accessor(Accessor &Other) = delete;
|
|
|
|
/// If the object is still owned when the lifetime ends we give up access.
|
|
~Accessor() { unlock(); }
|
|
|
|
/// Give up access to the underlying object, virtually "destroying" the
|
|
/// accessor even if the object is still life.
|
|
void destroy() {
|
|
unlock();
|
|
Ptr = nullptr;
|
|
}
|
|
|
|
/// Provide transparent access to the underlying object.
|
|
Ty &operator*() {
|
|
assert(Ptr && "Trying to access an object through a non-owning (or "
|
|
"destroyed) accessor!");
|
|
return Ptr->Obj;
|
|
}
|
|
Ty *operator->() {
|
|
assert(Ptr && "Trying to access an object through a non-owning (or "
|
|
"destroyed) accessor!");
|
|
return &Ptr->Obj;
|
|
}
|
|
|
|
private:
|
|
/// Lock the underlying object if there is one.
|
|
void lock() {
|
|
if (Ptr)
|
|
Ptr->Mtx.lock();
|
|
}
|
|
|
|
/// Unlock the underlying object if there is one.
|
|
void unlock() {
|
|
if (Ptr)
|
|
Ptr->Mtx.unlock();
|
|
}
|
|
|
|
/// Pointer to the underlying object or null if the accessor lost access,
|
|
/// e.g., after a destroy call.
|
|
ProtectedObj<Ty> *Ptr;
|
|
};
|
|
|
|
template <typename Ty>
|
|
Accessor<Ty> ProtectedObj<Ty>::getExclusiveAccessor(bool DoNotGetAccess) {
|
|
if (DoNotGetAccess)
|
|
return Accessor<Ty>();
|
|
return Accessor<Ty>(*this);
|
|
}
|
|
|
|
#endif
|