[libomptarget] Fix environment variable checks when initializing devices

Change-Id: Ib8f934b861762bb178e8abf28440a0f628509d36
ROCm · Mar 6, 2024 · be5eca3 · be5eca3
1 parent 7e1efa2
commit be5eca3
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Showing 4 changed files with 9 additions and 22 deletions.
diff --git a/openmp/libomptarget/include/device.h b/openmp/libomptarget/include/device.h
@@ -51,12 +51,6 @@ struct DeviceTy {
   /// Controlled via environment flag OMPX_FORCE_SYNC_REGIONS
   bool ForceSynchronousTargetRegions = false;
 
-  /// Flag that indicates whether the user requested eager zero-copy maps
-  /// to execute their application. Even if true, this is only valid on certain
-  /// architectures and configurations, which is checked upon device
-  /// initialization.
-  bool EagerZeroCopyMaps = false;
-
   DeviceTy(PluginAdaptorTy *RTL, int32_t DeviceID, int32_t RTLDeviceID);
   // DeviceTy is not copyable
   DeviceTy(const DeviceTy &D) = delete;

diff --git a/openmp/libomptarget/src/OpenMP/Mapping.cpp b/openmp/libomptarget/src/OpenMP/Mapping.cpp
@@ -280,7 +280,7 @@ TargetPointerResultTy MappingInfoTy::getTargetPointer(
       // If we are here, it means that we are either in auto zero-copy or USM.
       // Enable GPU page table prefaulting if selected by the user. This feature
       // is only enabled for APUs.
-      if (Device.EagerZeroCopyMaps) {
+      if (PM->getRequirements() & OMPX_REQ_EAGER_ZERO_COPY_MAPS) {
         Device.RTL->prepopulate_page_table(Device.DeviceID, HstPtrBegin, Size);
         INFO(OMP_INFOTYPE_MAPPING_CHANGED, Device.DeviceID,
              "Prefaulted " DPxMOD " Size=%" PRId64 " on GPU page table\n",

diff --git a/openmp/libomptarget/src/PluginManager.cpp b/openmp/libomptarget/src/PluginManager.cpp
@@ -139,9 +139,6 @@ void PluginAdaptorTy::initDevices(PluginManager &PM) {
   // The following properties must have the same value for all devices.
   // They are surfaced per-device because the related properties
   // are computed as such in the plugins.
-  bool EagerMapsRequested = false;
-  bool IsAPU = false;
-  bool SupportsUnifiedMemory = false;
   for (int32_t PDevI = 0, UserDevId = DeviceOffset; PDevI < NumPD; PDevI++) {
     auto Device = std::make_unique<DeviceTy>(this, UserDevId, PDevI);
     if (auto Err = Device->init()) {
@@ -150,23 +147,24 @@ void PluginAdaptorTy::initDevices(PluginManager &PM) {
       continue;
     }
     UseAutoZeroCopy = UseAutoZeroCopy && Device->useAutoZeroCopy();
-    SupportsUnifiedMemory =
-        SupportsUnifiedMemory && Device->supportsUnifiedMemory();
 
     ExclusiveDevicesAccessor->push_back(std::move(Device));
     ++NumberOfUserDevices;
     ++UserDevId;
   }
 
-  // IsAPU and EagerMapsRequested are properties associated
-  // with devices but they must be the same for all devices.
-  // We do not mix APUs with discrete GPUs and eager maps
-  // is set by an host environment variable.
+  // IsAPU, EagerMapsRequested and SupportsUnifiedMemory are properties
+  // associated with devices but they must be the same for all devices.
+  // We do not mix APUs with discrete GPUs. Eager maps is set by a host
+  // environment variable.
+  bool IsAPU = false;
+  bool SupportsUnifiedMemory = false;
   if (ExclusiveDevicesAccessor->size() > 0) {
     auto &Device = *(*ExclusiveDevicesAccessor)[0];
     IsAPU = Device.checkIfAPU();
-    EagerMapsRequested = Device.EagerZeroCopyMaps;
+    SupportsUnifiedMemory = Device.supportsUnifiedMemory();
   }
+  bool EagerMapsRequested = BoolEnvar("OMPX_EAGER_ZERO_COPY_MAPS", false).get();
 
   // Auto Zero-Copy can only be currently triggered when the system is an
   // homogeneous APU architecture without attached discrete GPUs.
@@ -185,7 +183,6 @@ void PluginAdaptorTy::initDevices(PluginManager &PM) {
   }
 
   // sanity checks for zero-copy depend on specific devices: request it here
-  // TODO: check if there are no devices and bail if so.
   if ((ExclusiveDevicesAccessor->size() > 0) &&
       ((PM.getRequirements() & OMP_REQ_UNIFIED_SHARED_MEMORY) ||
        (PM.getRequirements() & OMPX_REQ_AUTO_ZERO_COPY))) {

diff --git a/openmp/libomptarget/src/omptarget.cpp b/openmp/libomptarget/src/omptarget.cpp
@@ -297,10 +297,6 @@ static int initLibrary(DeviceTy &Device) {
   static BoolEnvar FSTEnvVar = BoolEnvar("OMPX_FORCE_SYNC_REGIONS", false);
   Device.ForceSynchronousTargetRegions = FSTEnvVar.get();
 
-  static BoolEnvar OMPX_EagerMaps =
-      BoolEnvar("OMPX_EAGER_ZERO_COPY_MAPS", false);
-  Device.EagerZeroCopyMaps = OMPX_EagerMaps.get();
-
   return OFFLOAD_SUCCESS;
 }