From 945f743aa7003b6cb6c646d9208713052cbc2701 Mon Sep 17 00:00:00 2001 From: Jonas Schievink Date: Tue, 27 Sep 2022 14:26:35 +0200 Subject: Add a `sched_getcpu` wrapper --- CHANGELOG.md | 2 ++ src/sched.rs | 7 +++++++ test/test_sched.rs | 6 +++++- 3 files changed, 14 insertions(+), 1 deletion(-) diff --git a/CHANGELOG.md b/CHANGELOG.md index 5982d70c..21d397e2 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -6,6 +6,8 @@ This project adheres to [Semantic Versioning](https://semver.org/). ## [Unreleased] - ReleaseDate ### Added +- Added `sched_getcpu` on platforms that support it. + ([#1825](https://github.com/nix-rust/nix/pull/1825)) - Added `sched_getaffinity` and `sched_setaffinity` on FreeBSD. ([#1804](https://github.com/nix-rust/nix/pull/1804)) - Added `line_discipline` field to `Termios` on Linux, Android and Haiku diff --git a/src/sched.rs b/src/sched.rs index 943ed6ec..aa2b90b4 100644 --- a/src/sched.rs +++ b/src/sched.rs @@ -290,6 +290,13 @@ mod sched_affinity { Errno::result(res).and(Ok(cpuset)) } + + /// Determines the CPU on which the calling thread is running. + pub fn sched_getcpu() -> Result { + let res = unsafe { libc::sched_getcpu() }; + + Errno::result(res).map(|int| int as usize) + } } /// Explicitly yield the processor to other threads. diff --git a/test/test_sched.rs b/test/test_sched.rs index ebf346db..c52616b8 100644 --- a/test/test_sched.rs +++ b/test/test_sched.rs @@ -1,4 +1,4 @@ -use nix::sched::{sched_getaffinity, sched_setaffinity, CpuSet}; +use nix::sched::{sched_getaffinity, sched_getcpu, sched_setaffinity, CpuSet}; use nix::unistd::Pid; #[test] @@ -30,6 +30,10 @@ fn test_sched_affinity() { ) } + // Now check that we're also currently running on the CPU in question. + let cur_cpu = sched_getcpu().unwrap(); + assert_eq!(cur_cpu, last_valid_cpu); + // Finally, reset the initial CPU set sched_setaffinity(Pid::from_raw(0), &initial_affinity).unwrap(); } -- cgit v1.2.3