Remove legacy SVM region concept.

Also rename blit_agent to region_gpu and add comments to clarify
its role in deprecated region API support rather than to do blits.

Change-Id: I80b1043db2e1c5d40a58fc801eef70a688ea9169

runtime/hsa-runtime/core/inc/runtime.h

@@ -290,7 +290,7 @@ class Runtime {
 
   const std::vector<uint32_t>& gpu_ids() { return gpu_ids_; }
 
-  Agent* blit_agent() { return blit_agent_; }
+  Agent* region_gpu() { return region_gpu_; }
 
   const std::vector<const MemoryRegion*>& system_regions_fine() const {
     return system_regions_fine_;
@@ -468,8 +468,8 @@ class Runtime {
   // Deallocator using ::system_region_
   std::function<void(void*)> system_deallocator_;
 
-  // Pointer to DMA agent.
-  Agent* blit_agent_;
+  // Deprecated HSA Region API GPU (for legacy APU support only)
+  Agent* region_gpu_;
 
   AsyncEventsControl async_events_control_;
 
@@ -477,17 +477,6 @@ class Runtime {
 
   AsyncEvents new_async_events_;
 
-  // Starting address of SVM address space.
-  // On APU the cpu and gpu could access the area inside starting and end of
-  // the SVM address space.
-  // On dGPU, only the gpu is guaranteed to have access to the area inside the
-  // SVM address space, since it maybe backed by private gpu VRAM.
-  uintptr_t start_svm_address_;
-
-  // End address of SVM address space.
-  // start_svm_address_ + size
-  uintptr_t end_svm_address_;
-
   // System clock frequency.
   uint64_t sys_clock_freq_;
 

runtime/hsa-runtime/core/runtime/amd_gpu_agent.cpp

@@ -461,8 +461,7 @@ hsa_status_t GpuAgent::VisitRegion(bool include_peer,
                                    void* data) const {
   if (include_peer) {
     // Only expose system, local, and LDS memory of the blit agent.
-    if (this->node_id() ==
-        core::Runtime::runtime_singleton_->blit_agent()->node_id()) {
+    if (this->node_id() == core::Runtime::runtime_singleton_->region_gpu()->node_id()) {
       hsa_status_t stat = VisitRegion(regions_, callback, data);
       if (stat != HSA_STATUS_SUCCESS) {
         return stat;

runtime/hsa-runtime/core/runtime/runtime.cpp

@@ -202,37 +202,8 @@ void Runtime::RegisterAgent(Agent* agent) {
 
     gpu_ids_.push_back(agent->node_id());
 
-    // Assign the first discovered gpu agent as blit agent that will provide
-    // DMA operation for hsa_memory_copy.
-    if (blit_agent_ == NULL) {
-      blit_agent_ = agent;
-
-      // Query the start and end address of the SVM address space in this
-      // platform.
-      if (reinterpret_cast<amd::GpuAgentInt*>(blit_agent_)->profile() ==
-          HSA_PROFILE_BASE) {
-        std::vector<const core::MemoryRegion*>::const_iterator it =
-            std::find_if(blit_agent_->regions().begin(),
-                         blit_agent_->regions().end(),
-                         [](const core::MemoryRegion* region) {
-              return (
-                  reinterpret_cast<const amd::MemoryRegion*>(region)->IsSvm());
-            });
-
-        assert(it != blit_agent_->regions().end());
-
-        const amd::MemoryRegion* svm_region =
-            reinterpret_cast<const amd::MemoryRegion*>(*it);
-
-        start_svm_address_ =
-            static_cast<uintptr_t>(svm_region->GetBaseAddress());
-        end_svm_address_ = start_svm_address_ + svm_region->GetPhysicalSize();
-      } else {
-        start_svm_address_ = 0;
-        end_svm_address_ = os::GetUserModeVirtualMemoryBase() +
-                           os::GetUserModeVirtualMemorySize();
-      }
-    }
+    // Assign the first discovered gpu agent as region gpu.
+    if (region_gpu_ == NULL) region_gpu_ = agent;
   }
 }
 
@@ -247,7 +218,7 @@ void Runtime::DestroyAgents() {
   std::for_each(cpu_agents_.begin(), cpu_agents_.end(), DeleteObject());
   cpu_agents_.clear();
 
-  blit_agent_ = NULL;
+  region_gpu_ = NULL;
 
   system_regions_fine_.clear();
   system_regions_coarse_.clear();
@@ -1191,19 +1162,12 @@ bool Runtime::VMFaultHandler(hsa_signal_value_t val, void* arg) {
 }
 
 Runtime::Runtime()
-    : blit_agent_(NULL),
+    : region_gpu_(nullptr),
       sys_clock_freq_(0),
       vm_fault_event_(nullptr),
       vm_fault_signal_(nullptr),
       system_event_handler_user_data_(nullptr),
-      ref_count_(0) {
-  start_svm_address_ = 0;
-#if defined(HSA_LARGE_MODEL)
-  end_svm_address_ = UINT64_MAX;
-#else
-  end_svm_address_ = UINT32_MAX;
-#endif
-}
+      ref_count_(0) {}
 
 hsa_status_t Runtime::Load() {
   flag_.Refresh();