[IOS] Improve the iOS RPC with exclusive filesys lock (#981)

.gitignore

@@ -139,6 +139,7 @@ xcuserdata/
 .DS_Store
 tags
 cscope*
+*.lock
 
 # vim temporary files
 *.swp

apps/ios_rpc/tests/ios_rpc_test.py

@@ -59,7 +59,6 @@ def test_rpc_module():
     # Start RPC test server that contains the compiled library.
     server = xcode.popen_test_rpc(proxy_host, proxy_port, key,
                                   destination=destination,
-                                  options=['-quiet'],
                                   libs=[path_dso1, path_dso2])
 
     # connect to the proxy

include/tvm/runtime/c_runtime_api.h

@@ -320,7 +320,7 @@ typedef void (*TVMPackedCFuncFinalizer)(void* resource_handle);
  *  TVM call this function to get the extension functions
  *  The declarer will call register_func to register function and their name.
  *
- * \param resource_func_handle The register function
+ * \param register_func_handle The register function
  * \return 0 if success, -1 if failure happens
  */
 typedef int (*TVMExtensionFuncDeclarer)(TVMFunctionHandle register_func_handle);

include/tvm/runtime/packed_func.h

@@ -688,11 +688,10 @@ inline TVMType String2TVMType(std::string s) {
     LOG(FATAL) << "unknown type " << s;
   }
   char* xdelim;  // emulate sscanf("%ux%u", bits, lanes)
-  unsigned bits = strtoul(scan, &xdelim, 10);
-  if (bits != 0) t.bits = static_cast<uint8_t>(bits);
+  uint8_t bits = static_cast<uint8_t>(strtoul(scan, &xdelim, 10));
+  if (bits != 0) t.bits = bits;
   if (*xdelim == 'x') {
-    unsigned lanes = strtoul(xdelim + 1, nullptr, 10);
-    t.lanes = static_cast<uint16_t>(lanes);
+    t.lanes = static_cast<uint16_t>(strtoul(xdelim + 1, nullptr, 10));
   }
   return t;
 }

python/tvm/contrib/rpc_proxy.py

@@ -392,7 +392,7 @@ class Proxy(object):
                  port=9091,
                  port_end=9199,
                  web_port=0,
-                 timeout_client=240,
+                 timeout_client=600,
                  timeout_server=600,
                  index_page=None,
                  resource_files=None):

python/tvm/contrib/util.py

@@ -2,6 +2,7 @@
 from __future__ import absolute_import as _abs
 import os
 import tempfile
+import fcntl
 import shutil
 
 class TempDirectory(object):
@@ -38,7 +39,7 @@ class TempDirectory(object):
         return os.path.join(self.temp_dir, name)
 
     def listdir(self):
-        """"List contents in the dir.
+        """List contents in the dir.
 
         Returns
         -------
@@ -47,6 +48,7 @@ class TempDirectory(object):
         """
         return os.listdir(self.temp_dir)
 
+
 def tempdir():
     """Create temp dir which deletes the contents when exit.
 
@@ -56,3 +58,38 @@ def tempdir():
         The temp directory object
     """
     return TempDirectory()
+
+
+class FileLock(object):
+    """File lock object
+
+    Parameters
+    ----------
+    path : str
+        The path to the lock
+    """
+    def __init__(self, path):
+        self.lock_file = open(path, "w")
+        fcntl.lockf(self.lock_file, fcntl.LOCK_EX)
+
+
+    def release(self):
+        """Release the lock"""
+        if self.lock_file:
+            fcntl.lockf(self.lock_file, fcntl.LOCK_UN)
+            self.lock_file.close()
+            self.lock_file = None
+
+def filelock(path):
+    """Create a file lock which locks on path
+
+    Parameters
+    ----------
+    path : str
+        The path to the lock
+
+    Returns
+    -------
+    lock : File lock object
+    """
+    return FileLock(path)

python/tvm/contrib/xcode.py

@@ -146,6 +146,28 @@ def compile_metal(code, path_target=None, sdk="macosx"):
     return libbin
 
 
+class XCodeRPCServer(object):
+    """Wrapper for RPC server
+
+    Parameters
+    ----------
+    cmd : list of str
+       The command to run
+
+    lock: FileLock
+       Lock on the path
+    """
+    def __init__(self, cmd, lock):
+        self.proc = subprocess.Popen(cmd)
+        self.lock = lock
+
+    def join(self):
+        """Wait server to finish and release its resource
+        """
+        self.proc.wait()
+        self.lock.release()
+
+
 def popen_test_rpc(host,
                    port,
                    key,
@@ -190,6 +212,10 @@ def popen_test_rpc(host,
     if not os.path.exists(proj_path):
         raise RuntimeError("Cannot find tvmrpc.xcodeproj in %s," +
                            (" please set env TVM_IOS_RPC_ROOT correctly" % rpc_root))
+
+    # Lock the path so only one file can run
+    lock = util.filelock(os.path.join(rpc_root, "ios_rpc.lock"))
+
     with open(os.path.join(rpc_root, "rpc_config.txt"), "w") as fo:
         fo.write("%s %d %s\n" % (host, port, key))
         libs = libs if libs else []
@@ -203,11 +229,5 @@ def popen_test_rpc(host,
     if options:
         cmd += options
     cmd += ["test"]
-    if "-quiet" in options:
-        with open(os.devnull, 'w') as devnull:
-            proc = subprocess.Popen(cmd,
-                                    stderr=subprocess.STDOUT,
-                                    stdout=devnull)
-    else:
-        proc = subprocess.Popen(cmd)
-    return proc
+
+    return XCodeRPCServer(cmd, lock)

src/runtime/graph/graph_runtime.cc

@@ -57,7 +57,7 @@ class GraphRuntime : public ModuleNode {
   }
   /*!
    * \brief Initialize the graph executor with graph and context.
-   * \param graph The execution graph.
+   * \param graph_json The execution graph.
    * \param module The module containing the compiled functions.
    * \param ctx The context where the graph should sit on
    */
@@ -94,7 +94,7 @@ class GraphRuntime : public ModuleNode {
   /*!
    * \brief set index-th input to the graph.
    * \param index The input index.
-   * \param data The input data.
+   * \param data_in The input data.
    */
   void SetInput(int index, DLTensor* data_in) {
     CHECK_LT(static_cast<size_t>(index), input_nodes_.size());