[driver] added driver source code from isaac repository

lib/driver/context.cpp

@@ -0,0 +1,99 @@
+/* Copyright 2015-2017 Philippe Tillet
+*
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files
+* (the "Software"), to deal in the Software without restriction,
+* including without limitation the rights to use, copy, modify, merge,
+* publish, distribute, sublicense, and/or sell copies of the Software,
+* and to permit persons to whom the Software is furnished to do so,
+* subject to the following conditions:
+*
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+#include <iostream>
+#include <cassert>
+
+#include "driver/context.h"
+#include "driver/module.h"
+
+#include "tools/sys/getenv.hpp"
+#include "tools/sys/mkdir.hpp"
+
+namespace tdl
+{
+
+namespace driver
+{
+
+std::string Context::get_cache_path(){
+  //user-specified cache path
+  std::string result = tools::getenv("ISAAC_CACHE_PATH");
+  if(!result.empty()){
+    if(tools::mkpath(result)==0)
+      return result;
+  }
+  //create in home
+  result = tools::getenv("HOME");
+  if(!result.empty())
+  {
+    result = result + "/.isaac/cache/";
+    if(tools::mkpath(result)==0)
+      return result;
+  }
+  //couldn't find a directory
+  return "";
+}
+
+CUdevice Context::device(CUcontext context){
+  dispatch::cuCtxPushCurrent_v2(context);
+  CUdevice res;
+  dispatch::cuCtxGetDevice(&res);
+  dispatch::cuCtxPopCurrent_v2(NULL);
+  return res;
+}
+
+Context::Context(CUcontext context, bool take_ownership): cu_(context, take_ownership), device_(device(context), false), cache_path_(get_cache_path())
+{ }
+
+Context::Context(Device const & device): device_(device), cache_path_(get_cache_path())
+{
+  dispatch::cuCtxCreate(&*cu_, CU_CTX_SCHED_AUTO, (CUdevice)device);
+  dispatch::cuCtxPopCurrent_v2(NULL);
+}
+
+Device const & Context::device() const
+{ return device_; }
+
+std::string const & Context::cache_path() const
+{ return cache_path_; }
+
+Handle<CUcontext> const & Context::cu() const
+{ return cu_; }
+
+/* Context Switcher */
+ContextSwitcher::ContextSwitcher(Context const & ctx): ctx_(ctx)
+{
+  dispatch::cuCtxPushCurrent_v2(ctx_);
+}
+
+ContextSwitcher::~ContextSwitcher()
+{
+  CUcontext tmp;
+  dispatch::cuCtxPopCurrent_v2(&tmp);
+  assert(tmp==(CUcontext)ctx_ && "Switching back to invalid context!");
+}
+
+
+
+}
+}