| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/root/.cargo/registry/src/github.com-1ecc6299db9ec823/num_cpus-1.15.0/src/lib.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>lib.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../normalize.css"><link rel="stylesheet" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../ayu.css" disabled><link rel="stylesheet" href="../../dark.css" disabled><link rel="stylesheet" href="../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../storage.js"></script><script defer src="../../source-script.js"></script><script defer src="../../source-files.js"></script><script defer src="../../main.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../num_cpus/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../num_cpus/index.html"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="doccomment">//! A crate with utilities to determine the number of CPUs available on the |
| //! current system. |
| //! |
| //! Sometimes the CPU will exaggerate the number of CPUs it contains, because it can use |
| //! [processor tricks] to deliver increased performance when there are more threads. This |
| //! crate provides methods to get both the logical and physical numbers of cores. |
| //! |
| //! This information can be used as a guide to how many tasks can be run in parallel. |
| //! There are many properties of the system architecture that will affect parallelism, |
| //! for example memory access speeds (for all the caches and RAM) and the physical |
| //! architecture of the processor, so the number of CPUs should be used as a rough guide |
| //! only. |
| //! |
| //! |
| //! ## Examples |
| //! |
| //! Fetch the number of logical CPUs. |
| //! |
| //! ``` |
| //! let cpus = num_cpus::get(); |
| //! ``` |
| //! |
| //! See [`rayon::Threadpool`] for an example of where the number of CPUs could be |
| //! used when setting up parallel jobs (Where the threadpool example uses a fixed |
| //! number 8, it could use the number of CPUs). |
| //! |
| //! [processor tricks]: https://en.wikipedia.org/wiki/Simultaneous_multithreading |
| //! [`rayon::ThreadPool`]: https://docs.rs/rayon/1.*/rayon/struct.ThreadPool.html |
| </span><span class="attribute">#![cfg_attr(test, deny(warnings))] |
| #![deny(missing_docs)] |
| #![allow(non_snake_case)] |
| |
| #[cfg(not(windows))] |
| </span><span class="kw">extern crate </span>libc; |
| |
| <span class="attribute">#[cfg(target_os = <span class="string">"hermit"</span>)] |
| </span><span class="kw">extern crate </span>hermit_abi; |
| |
| <span class="attribute">#[cfg(target_os = <span class="string">"linux"</span>)] |
| </span><span class="kw">mod </span>linux; |
| <span class="attribute">#[cfg(target_os = <span class="string">"linux"</span>)] |
| </span><span class="kw">use </span>linux::{get_num_cpus, get_num_physical_cpus}; |
| |
| <span class="doccomment">/// Returns the number of available CPUs of the current system. |
| /// |
| /// This function will get the number of logical cores. Sometimes this is different from the number |
| /// of physical cores (See [Simultaneous multithreading on Wikipedia][smt]). |
| /// |
| /// This will always return at least `1`. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// let cpus = num_cpus::get(); |
| /// if cpus > 1 { |
| /// println!("We are on a multicore system with {} CPUs", cpus); |
| /// } else { |
| /// println!("We are on a single core system"); |
| /// } |
| /// ``` |
| /// |
| /// # Note |
| /// |
| /// This will check [sched affinity] on Linux, showing a lower number of CPUs if the current |
| /// thread does not have access to all the computer's CPUs. |
| /// |
| /// This will also check [cgroups], frequently used in containers to constrain CPU usage. |
| /// |
| /// [smt]: https://en.wikipedia.org/wiki/Simultaneous_multithreading |
| /// [sched affinity]: http://www.gnu.org/software/libc/manual/html_node/CPU-Affinity.html |
| /// [cgroups]: https://www.kernel.org/doc/Documentation/cgroup-v1/cgroups.txt |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub fn </span>get() -> usize { |
| get_num_cpus() |
| } |
| |
| <span class="doccomment">/// Returns the number of physical cores of the current system. |
| /// |
| /// This will always return at least `1`. |
| /// |
| /// # Note |
| /// |
| /// Physical count is supported only on Linux, mac OS and Windows platforms. |
| /// On other platforms, or if the physical count fails on supported platforms, |
| /// this function returns the same as [`get()`], which is the number of logical |
| /// CPUS. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// let logical_cpus = num_cpus::get(); |
| /// let physical_cpus = num_cpus::get_physical(); |
| /// if logical_cpus > physical_cpus { |
| /// println!("We have simultaneous multithreading with about {:.2} \ |
| /// logical cores to 1 physical core.", |
| /// (logical_cpus as f64) / (physical_cpus as f64)); |
| /// } else if logical_cpus == physical_cpus { |
| /// println!("Either we don't have simultaneous multithreading, or our \ |
| /// system doesn't support getting the number of physical CPUs."); |
| /// } else { |
| /// println!("We have less logical CPUs than physical CPUs, maybe we only have access to \ |
| /// some of the CPUs on our system."); |
| /// } |
| /// ``` |
| /// |
| /// [`get()`]: fn.get.html |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub fn </span>get_physical() -> usize { |
| get_num_physical_cpus() |
| } |
| |
| |
| <span class="attribute">#[cfg(not(any(target_os = <span class="string">"linux"</span>, target_os = <span class="string">"windows"</span>, target_os=<span class="string">"macos"</span>, target_os=<span class="string">"openbsd"</span>)))] |
| #[inline] |
| </span><span class="kw">fn </span>get_num_physical_cpus() -> usize { |
| <span class="comment">// Not implemented, fall back |
| </span>get_num_cpus() |
| } |
| |
| <span class="attribute">#[cfg(target_os = <span class="string">"windows"</span>)] |
| </span><span class="kw">fn </span>get_num_physical_cpus() -> usize { |
| <span class="kw">match </span>get_num_physical_cpus_windows() { |
| <span class="prelude-val">Some</span>(num) => num, |
| <span class="prelude-val">None </span>=> get_num_cpus() |
| } |
| } |
| |
| <span class="attribute">#[cfg(target_os = <span class="string">"windows"</span>)] |
| </span><span class="kw">fn </span>get_num_physical_cpus_windows() -> <span class="prelude-ty">Option</span><usize> { |
| <span class="comment">// Inspired by https://msdn.microsoft.com/en-us/library/ms683194 |
| |
| </span><span class="kw">use </span>std::ptr; |
| <span class="kw">use </span>std::mem; |
| |
| <span class="attribute">#[allow(non_upper_case_globals)] |
| </span><span class="kw">const </span>RelationProcessorCore: u32 = <span class="number">0</span>; |
| |
| <span class="attribute">#[repr(C)] |
| #[allow(non_camel_case_types)] |
| </span><span class="kw">struct </span>SYSTEM_LOGICAL_PROCESSOR_INFORMATION { |
| mask: usize, |
| relationship: u32, |
| _unused: [u64; <span class="number">2</span>] |
| } |
| |
| <span class="kw">extern </span><span class="string">"system" </span>{ |
| <span class="kw">fn </span>GetLogicalProcessorInformation( |
| info: <span class="kw-2">*mut </span>SYSTEM_LOGICAL_PROCESSOR_INFORMATION, |
| length: <span class="kw-2">&mut </span>u32 |
| ) -> u32; |
| } |
| |
| <span class="comment">// First we need to determine how much space to reserve. |
| |
| // The required size of the buffer, in bytes. |
| </span><span class="kw">let </span><span class="kw-2">mut </span>needed_size = <span class="number">0</span>; |
| |
| <span class="kw">unsafe </span>{ |
| GetLogicalProcessorInformation(ptr::null_mut(), <span class="kw-2">&mut </span>needed_size); |
| } |
| |
| <span class="kw">let </span>struct_size = mem::size_of::<SYSTEM_LOGICAL_PROCESSOR_INFORMATION>() <span class="kw">as </span>u32; |
| |
| <span class="comment">// Could be 0, or some other bogus size. |
| </span><span class="kw">if </span>needed_size == <span class="number">0 </span>|| needed_size < struct_size || needed_size % struct_size != <span class="number">0 </span>{ |
| <span class="kw">return </span><span class="prelude-val">None</span>; |
| } |
| |
| <span class="kw">let </span>count = needed_size / struct_size; |
| |
| <span class="comment">// Allocate some memory where we will store the processor info. |
| </span><span class="kw">let </span><span class="kw-2">mut </span>buf = Vec::with_capacity(count <span class="kw">as </span>usize); |
| |
| <span class="kw">let </span>result; |
| |
| <span class="kw">unsafe </span>{ |
| result = GetLogicalProcessorInformation(buf.as_mut_ptr(), <span class="kw-2">&mut </span>needed_size); |
| } |
| |
| <span class="comment">// Failed for any reason. |
| </span><span class="kw">if </span>result == <span class="number">0 </span>{ |
| <span class="kw">return </span><span class="prelude-val">None</span>; |
| } |
| |
| <span class="kw">let </span>count = needed_size / struct_size; |
| |
| <span class="kw">unsafe </span>{ |
| buf.set_len(count <span class="kw">as </span>usize); |
| } |
| |
| <span class="kw">let </span>phys_proc_count = buf.iter() |
| <span class="comment">// Only interested in processor packages (physical processors.) |
| </span>.filter(|proc_info| proc_info.relationship == RelationProcessorCore) |
| .count(); |
| |
| <span class="kw">if </span>phys_proc_count == <span class="number">0 </span>{ |
| <span class="prelude-val">None |
| </span>} <span class="kw">else </span>{ |
| <span class="prelude-val">Some</span>(phys_proc_count) |
| } |
| } |
| |
| <span class="attribute">#[cfg(windows)] |
| </span><span class="kw">fn </span>get_num_cpus() -> usize { |
| <span class="attribute">#[repr(C)] |
| </span><span class="kw">struct </span>SYSTEM_INFO { |
| wProcessorArchitecture: u16, |
| wReserved: u16, |
| dwPageSize: u32, |
| lpMinimumApplicationAddress: <span class="kw-2">*mut </span>u8, |
| lpMaximumApplicationAddress: <span class="kw-2">*mut </span>u8, |
| dwActiveProcessorMask: <span class="kw-2">*mut </span>u8, |
| dwNumberOfProcessors: u32, |
| dwProcessorType: u32, |
| dwAllocationGranularity: u32, |
| wProcessorLevel: u16, |
| wProcessorRevision: u16, |
| } |
| |
| <span class="kw">extern </span><span class="string">"system" </span>{ |
| <span class="kw">fn </span>GetSystemInfo(lpSystemInfo: <span class="kw-2">*mut </span>SYSTEM_INFO); |
| } |
| |
| <span class="kw">unsafe </span>{ |
| <span class="kw">let </span><span class="kw-2">mut </span>sysinfo: SYSTEM_INFO = std::mem::zeroed(); |
| GetSystemInfo(<span class="kw-2">&mut </span>sysinfo); |
| sysinfo.dwNumberOfProcessors <span class="kw">as </span>usize |
| } |
| } |
| |
| <span class="attribute">#[cfg(any(target_os = <span class="string">"freebsd"</span>, |
| target_os = <span class="string">"dragonfly"</span>, |
| target_os = <span class="string">"netbsd"</span>))] |
| </span><span class="kw">fn </span>get_num_cpus() -> usize { |
| <span class="kw">use </span>std::ptr; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>cpus: libc::c_uint = <span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>cpus_size = std::mem::size_of_val(<span class="kw-2">&</span>cpus); |
| |
| <span class="kw">unsafe </span>{ |
| cpus = libc::sysconf(libc::_SC_NPROCESSORS_ONLN) <span class="kw">as </span>libc::c_uint; |
| } |
| <span class="kw">if </span>cpus < <span class="number">1 </span>{ |
| <span class="kw">let </span><span class="kw-2">mut </span>mib = [libc::CTL_HW, libc::HW_NCPU, <span class="number">0</span>, <span class="number">0</span>]; |
| <span class="kw">unsafe </span>{ |
| libc::sysctl(mib.as_mut_ptr(), |
| <span class="number">2</span>, |
| <span class="kw-2">&mut </span>cpus <span class="kw">as </span><span class="kw-2">*mut </span><span class="kw">_ as </span><span class="kw-2">*mut </span><span class="kw">_</span>, |
| <span class="kw-2">&mut </span>cpus_size <span class="kw">as </span><span class="kw-2">*mut </span><span class="kw">_ as </span><span class="kw-2">*mut </span><span class="kw">_</span>, |
| ptr::null_mut(), |
| <span class="number">0</span>); |
| } |
| <span class="kw">if </span>cpus < <span class="number">1 </span>{ |
| cpus = <span class="number">1</span>; |
| } |
| } |
| cpus <span class="kw">as </span>usize |
| } |
| |
| <span class="attribute">#[cfg(target_os = <span class="string">"openbsd"</span>)] |
| </span><span class="kw">fn </span>get_num_cpus() -> usize { |
| <span class="kw">use </span>std::ptr; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>cpus: libc::c_uint = <span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>cpus_size = std::mem::size_of_val(<span class="kw-2">&</span>cpus); |
| <span class="kw">let </span><span class="kw-2">mut </span>mib = [libc::CTL_HW, libc::HW_NCPUONLINE, <span class="number">0</span>, <span class="number">0</span>]; |
| <span class="kw">let </span>rc: libc::c_int; |
| |
| <span class="kw">unsafe </span>{ |
| rc = libc::sysctl(mib.as_mut_ptr(), |
| <span class="number">2</span>, |
| <span class="kw-2">&mut </span>cpus <span class="kw">as </span><span class="kw-2">*mut </span><span class="kw">_ as </span><span class="kw-2">*mut </span><span class="kw">_</span>, |
| <span class="kw-2">&mut </span>cpus_size <span class="kw">as </span><span class="kw-2">*mut </span><span class="kw">_ as </span><span class="kw-2">*mut </span><span class="kw">_</span>, |
| ptr::null_mut(), |
| <span class="number">0</span>); |
| } |
| <span class="kw">if </span>rc < <span class="number">0 </span>{ |
| cpus = <span class="number">1</span>; |
| } |
| cpus <span class="kw">as </span>usize |
| } |
| |
| <span class="attribute">#[cfg(target_os = <span class="string">"openbsd"</span>)] |
| </span><span class="kw">fn </span>get_num_physical_cpus() -> usize { |
| <span class="kw">use </span>std::ptr; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>cpus: libc::c_uint = <span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>cpus_size = std::mem::size_of_val(<span class="kw-2">&</span>cpus); |
| <span class="kw">let </span><span class="kw-2">mut </span>mib = [libc::CTL_HW, libc::HW_NCPU, <span class="number">0</span>, <span class="number">0</span>]; |
| <span class="kw">let </span>rc: libc::c_int; |
| |
| <span class="kw">unsafe </span>{ |
| rc = libc::sysctl(mib.as_mut_ptr(), |
| <span class="number">2</span>, |
| <span class="kw-2">&mut </span>cpus <span class="kw">as </span><span class="kw-2">*mut </span><span class="kw">_ as </span><span class="kw-2">*mut </span><span class="kw">_</span>, |
| <span class="kw-2">&mut </span>cpus_size <span class="kw">as </span><span class="kw-2">*mut </span><span class="kw">_ as </span><span class="kw-2">*mut </span><span class="kw">_</span>, |
| ptr::null_mut(), |
| <span class="number">0</span>); |
| } |
| <span class="kw">if </span>rc < <span class="number">0 </span>{ |
| cpus = <span class="number">1</span>; |
| } |
| cpus <span class="kw">as </span>usize |
| } |
| |
| |
| <span class="attribute">#[cfg(target_os = <span class="string">"macos"</span>)] |
| </span><span class="kw">fn </span>get_num_physical_cpus() -> usize { |
| <span class="kw">use </span>std::ffi::CStr; |
| <span class="kw">use </span>std::ptr; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>cpus: i32 = <span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>cpus_size = std::mem::size_of_val(<span class="kw-2">&</span>cpus); |
| |
| <span class="kw">let </span>sysctl_name = CStr::from_bytes_with_nul(<span class="string">b"hw.physicalcpu\0"</span>) |
| .expect(<span class="string">"byte literal is missing NUL"</span>); |
| |
| <span class="kw">unsafe </span>{ |
| <span class="kw">if </span><span class="number">0 </span>!= libc::sysctlbyname(sysctl_name.as_ptr(), |
| <span class="kw-2">&mut </span>cpus <span class="kw">as </span><span class="kw-2">*mut </span><span class="kw">_ as </span><span class="kw-2">*mut </span><span class="kw">_</span>, |
| <span class="kw-2">&mut </span>cpus_size <span class="kw">as </span><span class="kw-2">*mut </span><span class="kw">_ as </span><span class="kw-2">*mut </span><span class="kw">_</span>, |
| ptr::null_mut(), |
| <span class="number">0</span>) { |
| <span class="kw">return </span>get_num_cpus(); |
| } |
| } |
| cpus <span class="kw">as </span>usize |
| } |
| |
| <span class="attribute">#[cfg(any( |
| target_os = <span class="string">"nacl"</span>, |
| target_os = <span class="string">"macos"</span>, |
| target_os = <span class="string">"ios"</span>, |
| target_os = <span class="string">"android"</span>, |
| target_os = <span class="string">"solaris"</span>, |
| target_os = <span class="string">"illumos"</span>, |
| target_os = <span class="string">"fuchsia"</span>) |
| )] |
| </span><span class="kw">fn </span>get_num_cpus() -> usize { |
| <span class="comment">// On ARM targets, processors could be turned off to save power. |
| // Use `_SC_NPROCESSORS_CONF` to get the real number. |
| </span><span class="attribute">#[cfg(any(target_arch = <span class="string">"arm"</span>, target_arch = <span class="string">"aarch64"</span>))] |
| </span><span class="kw">const </span>CONF_NAME: libc::c_int = libc::_SC_NPROCESSORS_CONF; |
| <span class="attribute">#[cfg(not(any(target_arch = <span class="string">"arm"</span>, target_arch = <span class="string">"aarch64"</span>)))] |
| </span><span class="kw">const </span>CONF_NAME: libc::c_int = libc::_SC_NPROCESSORS_ONLN; |
| |
| <span class="kw">let </span>cpus = <span class="kw">unsafe </span>{ libc::sysconf(CONF_NAME) }; |
| <span class="kw">if </span>cpus < <span class="number">1 </span>{ |
| <span class="number">1 |
| </span>} <span class="kw">else </span>{ |
| cpus <span class="kw">as </span>usize |
| } |
| } |
| |
| <span class="attribute">#[cfg(target_os = <span class="string">"haiku"</span>)] |
| </span><span class="kw">fn </span>get_num_cpus() -> usize { |
| <span class="kw">use </span>std::mem; |
| |
| <span class="attribute">#[allow(non_camel_case_types)] |
| </span><span class="kw">type </span>bigtime_t = i64; |
| <span class="attribute">#[allow(non_camel_case_types)] |
| </span><span class="kw">type </span>status_t = i32; |
| |
| <span class="attribute">#[repr(C)] |
| </span><span class="kw">pub struct </span>system_info { |
| <span class="kw">pub </span>boot_time: bigtime_t, |
| <span class="kw">pub </span>cpu_count: u32, |
| <span class="kw">pub </span>max_pages: u64, |
| <span class="kw">pub </span>used_pages: u64, |
| <span class="kw">pub </span>cached_pages: u64, |
| <span class="kw">pub </span>block_cache_pages: u64, |
| <span class="kw">pub </span>ignored_pages: u64, |
| <span class="kw">pub </span>needed_memory: u64, |
| <span class="kw">pub </span>free_memory: u64, |
| <span class="kw">pub </span>max_swap_pages: u64, |
| <span class="kw">pub </span>free_swap_pages: u64, |
| <span class="kw">pub </span>page_faults: u32, |
| <span class="kw">pub </span>max_sems: u32, |
| <span class="kw">pub </span>used_sems: u32, |
| <span class="kw">pub </span>max_ports: u32, |
| <span class="kw">pub </span>used_ports: u32, |
| <span class="kw">pub </span>max_threads: u32, |
| <span class="kw">pub </span>used_threads: u32, |
| <span class="kw">pub </span>max_teams: u32, |
| <span class="kw">pub </span>used_teams: u32, |
| <span class="kw">pub </span>kernel_name: [::std::os::raw::c_char; <span class="number">256usize</span>], |
| <span class="kw">pub </span>kernel_build_date: [::std::os::raw::c_char; <span class="number">32usize</span>], |
| <span class="kw">pub </span>kernel_build_time: [::std::os::raw::c_char; <span class="number">32usize</span>], |
| <span class="kw">pub </span>kernel_version: i64, |
| <span class="kw">pub </span>abi: u32, |
| } |
| |
| <span class="kw">extern </span>{ |
| <span class="kw">fn </span>get_system_info(info: <span class="kw-2">*mut </span>system_info) -> status_t; |
| } |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>info: system_info = <span class="kw">unsafe </span>{ mem::zeroed() }; |
| <span class="kw">let </span>status = <span class="kw">unsafe </span>{ get_system_info(<span class="kw-2">&mut </span>info <span class="kw">as </span><span class="kw-2">*mut </span><span class="kw">_</span>) }; |
| <span class="kw">if </span>status == <span class="number">0 </span>{ |
| info.cpu_count <span class="kw">as </span>usize |
| } <span class="kw">else </span>{ |
| <span class="number">1 |
| </span>} |
| } |
| |
| <span class="attribute">#[cfg(target_os = <span class="string">"hermit"</span>)] |
| </span><span class="kw">fn </span>get_num_cpus() -> usize { |
| <span class="kw">unsafe </span>{ hermit_abi::get_processor_count() } |
| } |
| |
| <span class="attribute">#[cfg(not(any( |
| target_os = <span class="string">"nacl"</span>, |
| target_os = <span class="string">"macos"</span>, |
| target_os = <span class="string">"ios"</span>, |
| target_os = <span class="string">"android"</span>, |
| target_os = <span class="string">"solaris"</span>, |
| target_os = <span class="string">"illumos"</span>, |
| target_os = <span class="string">"fuchsia"</span>, |
| target_os = <span class="string">"linux"</span>, |
| target_os = <span class="string">"openbsd"</span>, |
| target_os = <span class="string">"freebsd"</span>, |
| target_os = <span class="string">"dragonfly"</span>, |
| target_os = <span class="string">"netbsd"</span>, |
| target_os = <span class="string">"haiku"</span>, |
| target_os = <span class="string">"hermit"</span>, |
| windows, |
| )))] |
| </span><span class="kw">fn </span>get_num_cpus() -> usize { |
| <span class="number">1 |
| </span>} |
| |
| <span class="attribute">#[cfg(test)] |
| </span><span class="kw">mod </span>tests { |
| <span class="kw">fn </span>env_var(name: <span class="kw-2">&</span><span class="lifetime">'static </span>str) -> <span class="prelude-ty">Option</span><usize> { |
| ::std::env::var(name).ok().map(|val| val.parse().unwrap()) |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_get() { |
| <span class="kw">let </span>num = <span class="kw">super</span>::get(); |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(n) = env_var(<span class="string">"NUM_CPUS_TEST_GET"</span>) { |
| <span class="macro">assert_eq!</span>(num, n); |
| } <span class="kw">else </span>{ |
| <span class="macro">assert!</span>(num > <span class="number">0</span>); |
| <span class="macro">assert!</span>(num < <span class="number">236_451</span>); |
| } |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_get_physical() { |
| <span class="kw">let </span>num = <span class="kw">super</span>::get_physical(); |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(n) = env_var(<span class="string">"NUM_CPUS_TEST_GET_PHYSICAL"</span>) { |
| <span class="macro">assert_eq!</span>(num, n); |
| } <span class="kw">else </span>{ |
| <span class="macro">assert!</span>(num > <span class="number">0</span>); |
| <span class="macro">assert!</span>(num < <span class="number">236_451</span>); |
| } |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="num_cpus" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
