Pepper: Narrow locking at llc subprocess start.

ppapi/native_client/src/trusted/plugin/pnacl_translate_thread.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ppapi/native_client/src/trusted/plugin/pnacl_translate_thread.h"
 
 #include <iterator>
 
 #include "native_client/src/trusted/desc/nacl_desc_wrapper.h"
 #include "ppapi/cpp/var.h"
@@ skipping 36 matching lines @@
   for (Args::const_iterator arg(args.begin()); arg != args.end(); ++arg) {
     std::copy(arg->begin(), arg->end(), std::back_inserter(*split_args));
     split_args->push_back('\x00');
   }
 }
 
 }  // namespace
 
 PnaclTranslateThread::PnaclTranslateThread() : llc_subprocess_active_(false),
                                                ld_subprocess_active_(false),
+                                               subprocesses_aborted_(false),
                                                done_(false),
                                                compile_time_(0),
                                                obj_files_(NULL),
                                                nexe_file_(NULL),
                                                coordinator_error_info_(NULL),
                                                resources_(NULL),
                                                coordinator_(NULL),
                                                plugin_(NULL) {
   NaClXMutexCtor(&subprocess_mu_);
   NaClXMutexCtor(&cond_mu_);
@@ skipping 86 matching lines @@
   ErrorInfo error_info;
   SrpcParams params;
   std::vector<nacl::DescWrapper*> llc_out_files;
   size_t i;
   for (i = 0; i < obj_files_->size(); i++)
     llc_out_files.push_back((*obj_files_)[i]->write_wrapper());
   for (; i < PnaclCoordinator::kMaxTranslatorObjectFiles; i++)
     llc_out_files.push_back(invalid_desc_wrapper_);
 
   pp::Core* core = pp::Module::Get()->core();
+  int64_t llc_start_time = NaClGetTimeOfDayMicroseconds();
+  PP_FileHandle llc_file_handle = resources_->TakeLlcFileHandle();
+  // On success, ownership of llc_file_handle is transferred.
+  NaClSubprocess* llc_subprocess = plugin_->LoadHelperNaClModule(
+      resources_->GetLlcUrl(), llc_file_handle, &error_info);
+  if (llc_subprocess == NULL) {
+    if (llc_file_handle != PP_kInvalidFileHandle)
+      CloseFileHandle(llc_file_handle);
+    TranslateFailed(PP_NACL_ERROR_PNACL_LLC_SETUP,
+                    "Compile process could not be created: " +
+                    error_info.message());
+    return;
+  }
+  core->CallOnMainThread(0,
+                         coordinator_->GetUMATimeCallback(
+                             "NaCl.Perf.PNaClLoadTime.LoadCompiler",
+                             NaClGetTimeOfDayMicroseconds() - llc_start_time),
+                         PP_OK);
+
   {
     nacl::MutexLocker ml(&subprocess_mu_);
-    int64_t llc_start_time = NaClGetTimeOfDayMicroseconds();
-    PP_FileHandle llc_file_handle = resources_->TakeLlcFileHandle();
-
-    // On success, ownership of llc_file_handle is transferred.
-    llc_subprocess_.reset(plugin_->LoadHelperNaClModule(
-        resources_->GetLlcUrl(), llc_file_handle, &error_info));
-    if (llc_subprocess_.get() == NULL) {
-      if (llc_file_handle != PP_kInvalidFileHandle)
-        CloseFileHandle(llc_file_handle);
-      TranslateFailed(PP_NACL_ERROR_PNACL_LLC_SETUP,
-                      "Compile process could not be created: " +
-                      error_info.message());
+    // If we received a call to AbortSubprocesses() before we had a chance to
+    // set llc_subprocess_, shut down and clean up the subprocess started here.
+    if (subprocesses_aborted_) {
+      llc_subprocess->service_runtime()->Shutdown();
+      delete llc_subprocess;
       return;
     }
-
+    llc_subprocess_.reset(llc_subprocess);
+    llc_subprocess = NULL;
     llc_subprocess_active_ = true;
-    core->CallOnMainThread(0,
-                           coordinator_->GetUMATimeCallback(
-                               "NaCl.Perf.PNaClLoadTime.LoadCompiler",
-                               NaClGetTimeOfDayMicroseconds() - llc_start_time),
-                           PP_OK);
   }
 
   int64_t compile_start_time = NaClGetTimeOfDayMicroseconds();
   bool init_success;
 
   std::vector<char> split_args;
   GetLlcCommandLine(plugin_,
                     &split_args,
                     obj_files_->size(),
                     pnacl_options_->opt_level,
@@ skipping 223 matching lines @@
   PLUGIN_PRINTF(("PnaclTranslateThread::AbortSubprocesses\n"));
   NaClXMutexLock(&subprocess_mu_);
   if (llc_subprocess_ != NULL && llc_subprocess_active_) {
     llc_subprocess_->service_runtime()->Shutdown();
     llc_subprocess_active_ = false;
   }
   if (ld_subprocess_ != NULL && ld_subprocess_active_) {
     ld_subprocess_->service_runtime()->Shutdown();
     ld_subprocess_active_ = false;
   }
+  subprocesses_aborted_ = true;
   NaClXMutexUnlock(&subprocess_mu_);
   nacl::MutexLocker ml(&cond_mu_);
   done_ = true;
   // Free all buffered bitcode chunks
   data_buffers_.clear();
   NaClXCondVarSignal(&buffer_cond_);
 }
 
 PnaclTranslateThread::~PnaclTranslateThread() {
   PLUGIN_PRINTF(("~PnaclTranslateThread (translate_thread=%p)\n", this));
   AbortSubprocesses();
   if (translate_thread_ != NULL)
     NaClThreadJoin(translate_thread_.get());
   PLUGIN_PRINTF(("~PnaclTranslateThread joined\n"));
   NaClCondVarDtor(&buffer_cond_);
   NaClMutexDtor(&cond_mu_);
   NaClMutexDtor(&subprocess_mu_);
 }
 
 } // namespace plugin