Add Read Mostly attribute support.

Change-Id: Ia7c60edacb892cbf14bdb50350c0a0a627e53964

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

@@ -1701,6 +1701,14 @@ hsa_status_t Runtime::SetSvmAttrib(void* ptr, size_t size,
           attribs.push_back(kmtPair(HSA_SVM_ATTR_PREFERRED_LOC, agent->node_id()));
         break;
       }
+      case HSA_AMD_SVM_ATTRIB_READ_MOSTLY: {
+        Check(attrib);
+        if (value)
+          set_flags |= HSA_SVM_FLAG_GPU_READ_MOSTLY;
+        else
+          clear_flags |= HSA_SVM_FLAG_GPU_READ_MOSTLY;
+        break;
+      }
       case HSA_AMD_SVM_ATTRIB_AGENT_ACCESSIBLE: {
         Agent* agent = Convert(value);
         ConfirmNew(agent);
@@ -1786,7 +1794,8 @@ hsa_status_t Runtime::GetSvmAttrib(void* ptr, size_t size,
     switch (attrib) {
       case HSA_AMD_SVM_ATTRIB_GLOBAL_FLAG:
       case HSA_AMD_SVM_ATTRIB_READ_ONLY:
-      case HSA_AMD_SVM_ATTRIB_HIVE_LOCAL: {
+      case HSA_AMD_SVM_ATTRIB_HIVE_LOCAL:
+      case HSA_AMD_SVM_ATTRIB_READ_MOSTLY: {
         getFlags = true;
         kmtIndices[i] = -1;
         break;
@@ -1868,6 +1877,10 @@ hsa_status_t Runtime::GetSvmAttrib(void* ptr, size_t size,
       case HSA_AMD_SVM_ATTRIB_PREFETCH_LOCATION: {
         break;
       }
+      case HSA_AMD_SVM_ATTRIB_READ_MOSTLY: {
+        value = (attribs[attribs.size() - 1].value & HSA_SVM_FLAG_GPU_READ_MOSTLY);
+        break;
+      }
       case HSA_AMD_SVM_ATTRIB_ACCESS_QUERY: {
         if (kmtIndices[i] == -1) {
           if (attribs[attribs.size() - 1].value & HSA_SVM_FLAG_HOST_ACCESS)

runtime/hsa-runtime/inc/hsa_ext_amd.h

@@ -2150,7 +2150,7 @@ typedef enum hsa_amd_svm_attribute_s {
   HSA_AMD_SVM_ATTRIB_PREFERRED_LOCATION = 4,
   // This attribute can not be used in ::hsa_amd_svm_attributes_set (see
   // ::hsa_amd_svm_prefetch_async).
-  // Physical location of most recent prefetch command.
+  // Queries the physical location of most recent prefetch command.
   // If the prefetch location has not been set or is not uniform across the
   // address range then returned hsa_agent_t::handle will be 0.
   // Querying this attribute will return the destination agent of the most
@@ -2160,6 +2160,10 @@ typedef enum hsa_amd_svm_attribute_s {
   // the location of the most recently completed prefetch.
   // Type of this attribute is hsa_agent_t.
   HSA_AMD_SVM_ATTRIB_PREFETCH_LOCATION = 5,
+  // Optimizes with the anticipation that the majority of operations to the
+  // range will be read operations.
+  // Type of this attribute is bool.
+  HSA_AMD_SVM_ATTRIB_READ_MOSTLY = 6,
   // This attribute can not be used in ::hsa_amd_svm_attributes_get.
   // Enables an agent for access to the range.  Access may incur a page fault
   // and associated memory migration.  Either this or