Merge pull request ucb-art#12 from hyunjaekwon/support_concurrent_dut…

…_creation

Support concurrent dut creation

src/bag/io/file.py

@@ -140,19 +140,22 @@ def readlines_iter(fname: Union[str, Path]) -> Iterable[str]:
             yield line
 
 
-def is_valid_file(fname: Union[str, Path], ready_str: Optional[str], timeout: float, wait_intvl: float) -> bool:
+def is_valid_file(fname: Union[str, Path], ready_str: Optional[str], timeout: float, wait_intvl: float,
+                  check_nonempty: bool = False) -> bool:
     """Checks if given file is valid by seeing if it exists and optionally contains a string.
 
     Parameters
     ----------
     fname : Union[str, Path]
         the file name.
     ready_str : Optional[str]
-        the string to check if file is ready. None if we should only check to see if file exists
+        the string to check if file is ready. None if we should only check to see if file exists.
     timeout : float
-        Maximum amount of time to wait.
-    wait_intvl: float
-        Amount of time in between iterations to check if file is ready
+        maximum amount of time to wait.
+    wait_intvl : float
+        amount of time in between iterations to check if file is ready.
+    check_nonempty : bool
+        True to check if file is not empty. Default is False.
 
     Returns
     -------
@@ -168,6 +171,13 @@ def is_valid_file(fname: Union[str, Path], ready_str: Optional[str], timeout: fl
         time.sleep(wait_intvl)
         iter_cnt += 1
 
+    if check_nonempty:
+        while fname.stat().st_size == 0:
+            if iter_cnt > max_iter:
+                return False
+            time.sleep(wait_intvl)
+            iter_cnt += 1
+
     if ready_str is None:
         return True
 

src/bag/simulation/cache.py

@@ -23,6 +23,7 @@
 
 import shutil
 import filecmp
+import tempfile
 from pathlib import Path
 from dataclasses import dataclass
 
@@ -201,13 +202,17 @@ async def _create_dut(self, impl_cell: str,
         exact_cell_names = {impl_cell}
 
         obj_cls = import_class(dut_cls)
+
+        # Create DUT layout and netlist in unique temporary directory to prevent overwriting of files
+        # during concurrent DUT creation
+        tmp_dir = Path(tempfile.mkdtemp('', 'tmp_', dir=self._root_dir))
         if issubclass(obj_cls, TemplateBase):
             self.log(f'Creating layout: {obj_cls.__name__}')
             lay_master = self._lay_db.new_template(obj_cls, params=dut_params)
             sch_params = lay_master.sch_params
             sch_cls = lay_master.get_schematic_class_inst()
             layout_hash = hash(lay_master.key)
-            gds_file = str(self._root_dir / 'tmp.gds')
+            gds_file = str(tmp_dir / 'tmp.gds')
             if export_lay:
                 self._lay_db.batch_layout([(lay_master, impl_cell)], output=DesignOutput.LAYOUT,
                                           name_prefix=name_prefix, name_suffix=name_suffix,
@@ -218,6 +223,7 @@ async def _create_dut(self, impl_cell: str,
                                           fname=gds_file, name_prefix=name_prefix,
                                           name_suffix=name_suffix,
                                           exact_cell_names=exact_cell_names)
+            assert is_valid_file(gds_file, None, 60, 1, True)
         else:
             if extract:
                 raise ValueError('Cannot run extraction without layout.')
@@ -235,7 +241,7 @@ async def _create_dut(self, impl_cell: str,
         sch_master: Module = self._sch_db.new_master(sch_cls, params=sch_params)
 
         # create schematic netlist
-        cdl_netlist = str(self._root_dir / 'tmp.cdl')
+        cdl_netlist = str(tmp_dir / 'tmp.cdl')
         cv_info_out = []
         sch_dut_list = [(sch_master, impl_cell)]
         self._sch_db.batch_schematic(sch_dut_list, output=DesignOutput.CDL,
@@ -247,6 +253,8 @@ async def _create_dut(self, impl_cell: str,
                                          name_prefix=name_prefix, name_suffix=name_suffix,
                                          exact_cell_names=exact_cell_names)
 
+        assert is_valid_file(cdl_netlist, None, 60, 1, True)
+
         self.log('Check for existing netlist')
         hash_id = combine_hash(layout_hash, hash(sch_master.key))
         dir_list = self._cache.get(hash_id, None)
@@ -271,6 +279,7 @@ async def _create_dut(self, impl_cell: str,
                 dir_path = self._generate_cell(impl_cell, cdl_netlist, gds_file)
                 dir_list.append(dir_path.name)
                 write_yaml(self._info_file, self._info_specs)
+            shutil.rmtree(tmp_dir)  # Remove temporary directory
 
         if extract or (extract is None and self._extract):
             ans = dir_path / 'rcx.sp'
@@ -343,7 +352,7 @@ def _generate_cell(self, impl_cell: str, cdl_netlist: str, gds_file: str) -> Pat
         dir_path.mkdir(parents=True, exist_ok=True)
 
         shutil.move(cdl_netlist, str(dir_path / 'netlist.cdl'))
-        if is_valid_file(gds_file, None, 60, 1):
+        if gds_file:
             shutil.move(gds_file, str(dir_path / 'layout.gds'))
         return dir_path