From b002c1485d26b2cbcaede258143613fdf2ad0aa1 Mon Sep 17 00:00:00 2001
From: Vojtech Bubnik <bubnikv@gmail.com>
Date: Mon, 4 Jan 2021 09:03:49 +0100
Subject: [PATCH] Fix of PrusaSlicer hangs on Linux when run with non standard
 task affinity #5661

---
 src/libslic3r/Thread.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/libslic3r/Thread.cpp b/src/libslic3r/Thread.cpp
index ad3e60b71..d203acb90 100644
--- a/src/libslic3r/Thread.cpp
+++ b/src/libslic3r/Thread.cpp
@@ -11,9 +11,9 @@
 #include <mutex>
 #include <tbb/parallel_for.h>
 #include <tbb/tbb_thread.h>
+#include <tbb/task_arena.h>
 #include <tbb/task_scheduler_init.h>
 
-
 #include "Thread.hpp"
 
 namespace Slic3r {
@@ -195,7 +195,10 @@ void name_tbb_thread_pool_threads()
 		return;
 	initialized = true;
 
-	const size_t nthreads_hw = std::thread::hardware_concurrency();
+	// see GH issue #5661 PrusaSlicer hangs on Linux when run with non standard task affinity
+	// TBB will respect the task affinity mask on Linux and spawn less threads than std::thread::hardware_concurrency().
+//	const size_t nthreads_hw = std::thread::hardware_concurrency();
+	const size_t nthreads_hw = tbb::this_task_arena::max_concurrency();
 	size_t 		 nthreads    = nthreads_hw;
 
 #ifdef SLIC3R_PROFILE