1 //===-- Generic utilities for GPU timing ----------------------------------===// 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_TIME_GPU_TIME_UTILS_H 10 #define LLVM_LIBC_SRC_TIME_GPU_TIME_UTILS_H 11 12 #include "hdr/time_macros.h" 13 #include "hdr/types/clock_t.h" 14 #include "src/__support/GPU/utils.h" 15 #include "src/__support/macros/config.h" 16 17 namespace LIBC_NAMESPACE_DECL { 18 19 #if defined(LIBC_TARGET_ARCH_IS_AMDGPU) 20 // AMDGPU does not have a single set frequency. Different architectures and 21 // cards can have different values. The actualy frequency needs to be read from 22 // the kernel driver and will be between 25 MHz and 100 MHz on most cards. All 23 // cards following the GFX9 ISAs use a 100 MHz clock so we will default to that. 24 constexpr uint64_t clock_freq = 100000000UL; 25 26 // We provide an externally visible symbol such that the runtime can set 27 // this to the correct value. 28 extern "C" { 29 [[gnu::visibility("protected")]] 30 extern gpu::Constant<uint64_t> __llvm_libc_clock_freq; 31 } 32 #define GPU_CLOCKS_PER_SEC static_cast<clock_t>(__llvm_libc_clock_freq) 33 34 #elif defined(LIBC_TARGET_ARCH_IS_NVPTX) 35 // NPVTX uses a single 1 GHz fixed frequency clock for all target architectures. 36 #define GPU_CLOCKS_PER_SEC static_cast<clock_t>(1000000000UL) 37 #else 38 #error "Unsupported target" 39 #endif 40 41 } // namespace LIBC_NAMESPACE_DECL 42 43 #endif // LLVM_LIBC_SRC_TIME_GPU_TIME_UTILS_H 44