Revert SVM and XNACK support.

KFD is not ready yet.

Change-Id: I61deb292ddb92185d33504c2115169888d56e211


[ROCm/ROCR-Runtime commit: 5bd153974d]

projects/rocr-runtime/runtime/hsa-runtime/core/util/flag.h

@@ -56,11 +56,6 @@ class Flag {
  public:
   enum SDMA_OVERRIDE { SDMA_DISABLE, SDMA_ENABLE, SDMA_DEFAULT };
 
-  // The values are meaningful and chosen to satisfy the thunk API.
-  enum XNACK_REQUEST { XNACK_DISABLE = 0, XNACK_ENABLE = 1, XNACK_UNCHANGED = 2 };
-  static_assert(XNACK_DISABLE == 0, "XNACK_REQUEST enum values improperly changed.");
-  static_assert(XNACK_ENABLE == 1, "XNACK_REQUEST enum values improperly changed.");
-
   enum FLAG_TRI_STATE { FLAG_DISABLE = 0, FLAG_ENABLE = 1, FLAG_DEFAULT = 2 };
 
   explicit Flag() { Refresh(); }
@@ -144,11 +139,6 @@ class Flag {
     var = os::GetEnvVar("HSA_IGNORE_SRAMECC_MISREPORT");
     check_sramecc_validity_ = (var == "1") ? false : true;
     
-    // Legal values are zero "0" or one "1". Any other value will
-    // be interpreted as not defining the env variable
-    var = os::GetEnvVar("HSA_XNACK");
-    xnack_ = (var == "0") ? XNACK_DISABLE : ((var == "1") ? XNACK_ENABLE : XNACK_UNCHANGED);
-
     // Legal values are zero "0" or one "1". Any other value will
     // be interpreted as not defining the env variable.
     var = os::GetEnvVar("HSA_FORCE_SRAMECC");
@@ -206,8 +196,6 @@ class Flag {
 
   bool check_sramecc_validity() const { return check_sramecc_validity_; }
 
-  XNACK_REQUEST xnack() const { return xnack_; }
-
   FLAG_TRI_STATE sramecc() const { return sramecc_; }
 
  private:
@@ -243,9 +231,6 @@ class Flag {
 
   size_t force_sdma_size_;
 
-  // Indicates user preference for Xnack state.
-  XNACK_REQUEST xnack_;
-
   // Indicates user preference for SramECC state.
   FLAG_TRI_STATE sramecc_;