From 8c0ff9508da5f02e8ce6580a126a2018c9bf702a Mon Sep 17 00:00:00 2001 From: Rafael Espindola Date: Wed, 4 Oct 2017 20:27:01 +0000 Subject: Bring r314809 back. But now include a check for CPU_COUNT so we still build on 10 year old versions of glibc. Original message: Use sched_getaffinity instead of std::thread::hardware_concurrency. The issue with std::thread::hardware_concurrency is that it forwards to libc and some implementations (like glibc) don't take thread affinity into consideration. With this change a llvm program that can execute in only 2 cores will use 2 threads, even if the machine has 32 cores. This makes benchmarking a lot easier, but should also help if someone doesn't want to use all cores for compilation for example. llvm-svn: 314931 --- llvm/lib/Support/ThreadPool.cpp | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'llvm/lib/Support/ThreadPool.cpp') diff --git a/llvm/lib/Support/ThreadPool.cpp b/llvm/lib/Support/ThreadPool.cpp index 22b7550d497..f1b5bdf40c3 100644 --- a/llvm/lib/Support/ThreadPool.cpp +++ b/llvm/lib/Support/ThreadPool.cpp @@ -14,14 +14,15 @@ #include "llvm/Support/ThreadPool.h" #include "llvm/Config/llvm-config.h" +#include "llvm/Support/Threading.h" #include "llvm/Support/raw_ostream.h" using namespace llvm; #if LLVM_ENABLE_THREADS -// Default to std::thread::hardware_concurrency -ThreadPool::ThreadPool() : ThreadPool(std::thread::hardware_concurrency()) {} +// Default to hardware_concurrency +ThreadPool::ThreadPool() : ThreadPool(hardware_concurrency()) {} ThreadPool::ThreadPool(unsigned ThreadCount) : ActiveThreads(0), EnableFlag(true) { -- cgit v1.2.3