cpuinfo - Cross-platform library for CPU information and performance optimization

CPU Information Library

The CPU Information Library, commonly referred to as cpuinfo, is a sophisticated tool designed to gather pivotal details about the host CPU, crucial for optimizing performance. This library provides a cross-platform solution compatible with various operating systems including Linux, Windows, macOS, Android, iOS, and FreeBSD, and supports architectures such as x86, x86-64, ARM, and ARM64.

Features

Cross-Platform Support: Ensures that cpuinfo can operate seamlessly across several major operating systems and on numerous hardware architectures.
Modern C/C++ Interface: This library is constructed with a modern programming interface that is thread-safe. It does not allocate memory post-initialization and does not throw exceptions, which makes it robust and reliable.
Instruction Set and Core Detection: It identifies which instruction sets your CPU supports, like AVX512 for x86 and ARMv8.3 for ARM architectures. It also detects detailed information about your CPU's architecture, vendor, and specific core technologies.
Comprehensive Cache Information: Provides details about the CPU cache, including cache type, size, line size, associativity, and the cores it shares the cache with.
Topology Information: Offers insights into the relationship between logical processors, cores, and CPU packages, helping in understanding how these elements interconnect and work together.
Production Quality: The library contains over 60 mock tests grounded on actual device data and includes work-arounds for known hardware and software kernel bugs, supporting systems with heterogeneous cores like big.LITTLE configurations.
Open Source License: It is available under a permissive BSD (2-Clause) license, promoting wide usage and adaptation.

Usage Examples

Here's how you can utilize cpuinfo in practice:

To log the CPU's name:

cpuinfo_initialize();
printf("Running on %s CPU\n", cpuinfo_get_package(0)->name);

To check if the system is using a 32-bit or 64-bit ARM architecture:

#if CPUINFO_ARCH_ARM || CPUINFO_ARCH_ARM64
    /* 32-bit ARM-specific code here */
#endif

To determine if the CPU supports ARM NEON:

cpuinfo_initialize();
if (cpuinfo_has_arm_neon()) {
    neon_implementation(arguments);
}

To confirm x86 AVX support:

cpuinfo_initialize();
if (cpuinfo_has_x86_avx()) {
    avx_implementation(arguments);
}

Integration in Build Systems

The library can be an integral part of various build setups:

Pkg-config: Ensures the build environment has necessary compiler and linker flags.
Autotools, Meson, Bazel, CMake, Makefile: Integrate easily with these build systems to compile projects relying on cpuinfo effectively.

Exposed Information

The library reveals a wealth of CPU information including:

Processor and microarchitecture specifics
Instruction sets utilization
Cache details (e.g., size, topology)
Topology map (logical processors, cores)

Supported Environments

Cpuinfo supports Android, Linux, iOS, macOS, Windows, and FreeBSD platforms across numerous architectures such as x86, x86-64, ARM, and ARM64.

Detection Methods

The library employs various methods to detect processor details, including but not limited to leveraging CPUID for x86, /proc/cpuinfo for ARM, and using system-specific calls like sysctlbyname for topology and cache information.

In summary, the cpuinfo library stands as a comprehensive tool for obtaining detailed, platform-independent CPU information crucial for performance tuning and optimization tasks. Whether for desktop, mobile, or embedded systems, it provides a robust framework for accessing critical CPU data efficiently and reliably.