tdf#103395 opencl: don't initialize OpenCL when disabled

If SAL_DISABLE_OPENCL is set we don't want to do any kind of
OpenCL initialization. Put an extra guard in fillOpenCLInfo
(and similar methods in opencl package) to prevent that.

Put the check if OpenCL can be used into one place which checks
SAL_DISABLE_OPENCL and UseOpenCL in configuration.

Reviewed-on: https://gerrit.libreoffice.org/30025
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>
(cherry picked from commit 21e8ed8b5f032f63012a7ee84bce64fac218154f)

Change-Id: Icc216d4299d3a7942843117ab9b9411de8075b11
Reviewed-on: https://gerrit.libreoffice.org/30220
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Michael Meeks <michael.meeks@collabora.com>

3 files changed, 23 insertions, 6 deletions

diff --git a/desktop/source/app/opencl.cxx b/desktop/source/app/opencl.cxx
index 13161f3a299f..791b7a91649e 100644
--- a/desktop/source/app/opencl.cxx
+++ b/desktop/source/app/opencl.cxx
@@ -117,8 +117,7 @@ bool testOpenCLCompute(const Reference< XDesktop2 > &xDesktop, const OUString &r
 
 void Desktop::CheckOpenCLCompute(const Reference< XDesktop2 > &xDesktop)
 {
-    if (getenv("SAL_DISABLE_OPENCL") ||
-        !officecfg::Office::Common::Misc::UseOpenCL::get())
+    if (!opencl::canUseOpenCL())
         return;
 
     SAL_INFO("opencl", "Initiating test of OpenCL device");
diff --git a/include/opencl/openclwrapper.hxx b/include/opencl/openclwrapper.hxx
index 233412fdb4eb..5f71b2a205f3 100644
--- a/include/opencl/openclwrapper.hxx
+++ b/include/opencl/openclwrapper.hxx
@@ -26,7 +26,8 @@
 
 #include <cstdio>
 
-namespace opencl {
+namespace opencl
+{
 
 struct KernelEnv
 {
@@ -56,6 +57,8 @@ struct OPENCL_DLLPUBLIC GPUEnv
 extern OPENCL_DLLPUBLIC GPUEnv gpuEnv;
 extern OPENCL_DLLPUBLIC sal_uInt64 kernelFailures;
 
+OPENCL_DLLPUBLIC bool canUseOpenCL();
+
 OPENCL_DLLPUBLIC bool generatBinFromKernelSource( cl_program program, const char * clFileName );
 OPENCL_DLLPUBLIC bool buildProgramFromBinary(const char* buildOption, GPUEnv* gpuEnv, const char* filename, int idx);
 OPENCL_DLLPUBLIC void setKernelEnv( KernelEnv *envInfo );
diff --git a/opencl/source/openclwrapper.cxx b/opencl/source/openclwrapper.cxx
index 5d40a54d806f..dcc55d06d9a3 100644
--- a/opencl/source/openclwrapper.cxx
+++ b/opencl/source/openclwrapper.cxx
@@ -32,6 +32,8 @@
 
 #include <cmath>
 
+#include <officecfg/Office/Common.hxx>
+
 #ifdef _WIN32
 #include <prewin.h>
 #include <postwin.h>
@@ -64,7 +66,8 @@ namespace opencl {
 GPUEnv gpuEnv;
 sal_uInt64 kernelFailures = 0;
 
-namespace {
+namespace
+{
 
 bool bIsInited = false;
 
@@ -693,7 +696,9 @@ bool createPlatformInfo(cl_platform_id nPlatformId, OpenCLPlatformInfo& rPlatfor
 const std::vector<OpenCLPlatformInfo>& fillOpenCLInfo()
 {
     static std::vector<OpenCLPlatformInfo> aPlatforms;
-    if(!aPlatforms.empty())
+
+    // return early if we already initialized or can't use OpenCL
+    if (!aPlatforms.empty() || !canUseOpenCL())
         return aPlatforms;
 
     int status = clewInit(OPENCL_DLL_NAME);
@@ -776,9 +781,16 @@ void findDeviceInfoFromDeviceId(cl_device_id aDeviceId, size_t& rDeviceId, size_
 
 }
 
+bool canUseOpenCL()
+{
+    if (getenv("SAL_DISABLE_OPENCL") || !officecfg::Office::Common::Misc::UseOpenCL::get())
+        return false;
+    return true;
+}
+
 bool switchOpenCLDevice(const OUString* pDevice, bool bAutoSelect, bool bForceEvaluation, OUString& rOutSelectedDeviceVersionIDString)
 {
-    if(fillOpenCLInfo().empty() || getenv("SAL_DISABLE_OPENCL"))
+    if (!canUseOpenCL() || fillOpenCLInfo().empty())
         return false;
 
     cl_device_id pDeviceId = nullptr;
@@ -854,6 +866,9 @@ bool switchOpenCLDevice(const OUString* pDevice, bool bAutoSelect, bool bForceEv
 
 void getOpenCLDeviceInfo(size_t& rDeviceId, size_t& rPlatformId)
 {
+    if (!canUseOpenCL())
+        return;
+
     int status = clewInit(OPENCL_DLL_NAME);
     if (status < 0)
         return;