xref: /aosp_15_r20/external/llvm-libc/src/__support/threads/gpu/mutex.h (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===--- Implementation of a GPU mutex class --------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_GPU_MUTEX_H
10 #define LLVM_LIBC_SRC___SUPPORT_THREADS_GPU_MUTEX_H
11 
12 #include "src/__support/macros/attributes.h"
13 #include "src/__support/macros/config.h"
14 #include "src/__support/threads/mutex_common.h"
15 
16 namespace LIBC_NAMESPACE_DECL {
17 
18 /// Implementation of a simple passthrough mutex which guards nothing. A
19 /// complete Mutex locks in general cannot be implemented on the GPU. We simply
20 /// define the Mutex interface and require that only a single thread executes
21 /// code requiring a mutex lock.
22 struct Mutex {
MutexMutex23   LIBC_INLINE constexpr Mutex(bool, bool, bool, bool) {}
24 
lockMutex25   LIBC_INLINE MutexError lock() { return MutexError::NONE; }
unlockMutex26   LIBC_INLINE MutexError unlock() { return MutexError::NONE; }
resetMutex27   LIBC_INLINE MutexError reset() { return MutexError::NONE; }
28 };
29 
30 } // namespace LIBC_NAMESPACE_DECL
31 
32 #endif // LLVM_LIBC_SRC___SUPPORT_THREADS_GPU_MUTEX_H
33