| commit | 81a5aaeaec4000f0e35f8c3ddd707bdefb20bad8 | [log] [tgz] |
|---|---|---|
| author | Marat Dukhan <maratek@google.com> | Tue Jul 18 18:44:11 2023 |
| committer | Marat Dukhan <maratek@gmail.com> | Tue Jul 18 18:54:36 2023 |
| tree | 9532bb6788df9049b26d6102c1ad4ff99e815bb7 | |
| parent | 87d8234510367db49a65535021af5e1838a65ac2 [diff] |
Detect AArch64-only big.LITTLE cores in AArch32 Some cores don't support AArch32, but can be used in heterogeneous SoC in combination with other cores which do support AArch32. In this case the cores are still reported in /proc/cpuinfo, and thus should be propertly handled to the uarch decoding code.
cpuinfo is a library to detect essential for performance optimization information about host CPU.
Log processor name:
cpuinfo_initialize(); printf("Running on %s CPU\n", cpuinfo_get_package(0)->name);
Detect if target is a 32-bit or 64-bit ARM system:
#if CPUINFO_ARCH_ARM || CPUINFO_ARCH_ARM64 /* 32-bit ARM-specific code here */ #endif
Check if the host CPU supports ARM NEON
cpuinfo_initialize(); if (cpuinfo_has_arm_neon()) { neon_implementation(arguments); }
Check if the host CPU supports x86 AVX
cpuinfo_initialize(); if (cpuinfo_has_x86_avx()) { avx_implementation(arguments); }
Check if the thread runs on a Cortex-A53 core
cpuinfo_initialize(); switch (cpuinfo_get_current_core()->uarch) { case cpuinfo_uarch_cortex_a53: cortex_a53_implementation(arguments); break; default: generic_implementation(arguments); break; }
Get the size of level 1 data cache on the fastest core in the processor (e.g. big core in big.LITTLE ARM systems):
cpuinfo_initialize(); const size_t l1_size = cpuinfo_get_processor(0)->cache.l1d->size;
Pin thread to cores sharing L2 cache with the current core (Linux or Android)
cpuinfo_initialize(); cpu_set_t cpu_set; CPU_ZERO(&cpu_set); const struct cpuinfo_cache* current_l2 = cpuinfo_get_current_processor()->cache.l2; for (uint32_t i = 0; i < current_l2->processor_count; i++) { CPU_SET(cpuinfo_get_processor(current_l2->processor_start + i)->linux_id, &cpu_set); } pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpu_set);
If you would like to provide your project's build environment with the necessary compiler and linker flags in a portable manner, the library by default when built enables CPUINFO_BUILD_PKG_CONFIG and will generate a pkg-config manifest (libcpuinfo.pc). Here are several examples of how to use it:
If you used your distro's package manager to install the library, you can verify that it is available to your build environment like so:
$ pkg-config --cflags --libs libcpuinfo -I/usr/include/x86_64-linux-gnu/ -L/lib/x86_64-linux-gnu/ -lcpuinfo
If you have installed the library from source into a non-standard prefix, pkg-config may need help finding it:
$ PKG_CONFIG_PATH="/home/me/projects/cpuinfo/prefix/lib/pkgconfig/:$PKG_CONFIG_PATH" pkg-config --cflags --libs libcpuinfo -I/home/me/projects/cpuinfo/prefix/include -L/home/me/projects/cpuinfo/prefix/lib -lcpuinfo
To use with the GNU Autotools include the following snippet in your project's configure.ac:
# CPU INFOrmation library... PKG_CHECK_MODULES( [libcpuinfo], [libcpuinfo], [], [AC_MSG_ERROR([libcpuinfo missing...])]) YOURPROJECT_CXXFLAGS="$YOURPROJECT_CXXFLAGS $libcpuinfo_CFLAGS" YOURPROJECT_LIBS="$YOURPROJECT_LIBS $libcpuinfo_LIBS"
To use with Meson you just need to add dependency('libcpuinfo') as a dependency for your executable.
project( 'MyCpuInfoProject', 'cpp', meson_version: '>=0.55.0' ) executable( 'MyCpuInfoExecutable', sources: 'main.cpp', dependencies: dependency('libcpuinfo') )
This project can be built using Bazel.
You can also use this library as a dependency to your Bazel project. Add to the WORKSPACE file:
load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository") git_repository( name = "org_pytorch_cpuinfo", branch = "master", remote = "https://github.com/Vertexwahn/cpuinfo.git", )
And to your BUILD file:
cc_binary( name = "cpuinfo_test", srcs = [ # ... ], deps = [ "@org_pytorch_cpuinfo//:cpuinfo", ], )
To use with CMake use the FindPkgConfig module. Here is an example:
cmake_minimum_required(VERSION 3.6) project("MyCpuInfoProject") find_package(PkgConfig) pkg_check_modules(CpuInfo REQUIRED IMPORTED_TARGET libcpuinfo) add_executable(${PROJECT_NAME} main.cpp) target_link_libraries(${PROJECT_NAME} PkgConfig::CpuInfo)
To use within a vanilla makefile, you can call pkg-config directly to supply compiler and linker flags using shell substitution.
CFLAGS=-g3 -Wall -Wextra -Werror ... LDFLAGS=-lfoo ... ... CFLAGS+= $(pkg-config --cflags libcpuinfo) LDFLAGS+= $(pkg-config --libs libcpuinfo)
/proc/cpuinfo on ARMro.chipname, ro.board.platform, ro.product.board, ro.mediatek.platform, ro.arch properties (Android)dmesg) on ARM Linux/proc/cpuinfo on 32-bit ARM EABI (Linux)FPSID and WCID registers (32-bit ARM)getauxval (Linux/ARM)/proc/self/auxv (Android/ARM)/proc/cpuinfo (Linux/pre-ARMv7)sysctlbyname (Mach)typology directories (ARM/Linux)cache directories (Linux)GetLogicalProcessorInformationEx on ARM64 Windows/proc/cpuinfo (Linux)host_info (Mach)GetLogicalProcessorInformationEx (Windows)