From 4e629000095779ae8f544ddd4de77633680a3db9 Mon Sep 17 00:00:00 2001
From: Alexander Alekhin <alexander.a.alekhin@gmail.com>
Date: Wed, 10 Oct 2018 19:57:43 +0000
Subject: [PATCH] core: call omp_set_dynamic() for better CPU usage

Similar to 'OMP_DYNAMIC=TRUE'.
---
 modules/core/src/parallel.cpp | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/modules/core/src/parallel.cpp b/modules/core/src/parallel.cpp
index f693da4c76..a32f2f178a 100644
--- a/modules/core/src/parallel.cpp
+++ b/modules/core/src/parallel.cpp
@@ -420,7 +420,16 @@ static int numThreads = -1;
 #elif defined HAVE_CSTRIPES
 // nothing for C=
 #elif defined HAVE_OPENMP
-static int numThreadsMax = omp_get_max_threads();
+static inline int _initMaxThreads()
+{
+    int maxThreads = omp_get_max_threads();
+    if (!utils::getConfigurationParameterBool("OPENCV_FOR_OPENMP_DYNAMIC_DISABLE", false))
+    {
+        omp_set_dynamic(maxThreads);
+    }
+    return numThreads;
+}
+static int numThreadsMax = _initMaxThreads();
 #elif defined HAVE_GCD
 // nothing for GCD
 #elif defined WINRT