Linux Sandbox: Stop GPU watchdog in accountable way.

sandbox/linux/services/thread_helpers_unittests.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 "sandbox/linux/services/thread_helpers.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "base/basictypes.h"
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/posix/eintr_wrapper.h"
+#include "base/process/process_metrics.h"
+#include "base/threading/platform_thread.h"
+#include "base/threading/thread.h"
+#include "sandbox/linux/tests/unit_tests.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using base::PlatformThread;
+
+namespace sandbox {
+
+namespace {
+
+int GetRaceTestIterations() {
+  if (IsRunningOnValgrind()) {
+    return 2;
+  } else {
+    return 1000;
+  }
+}
+
+class ScopedProcSelfTask {
+ public:
+  ScopedProcSelfTask() : fd_(-1) {
+    fd_ = open("/proc/self/task/", O_RDONLY | O_DIRECTORY);
+    CHECK_LE(0, fd_);
+  }
+
+  ~ScopedProcSelfTask() { PCHECK(0 == IGNORE_EINTR(close(fd_))); }
+
+  int fd() { return fd_; }
+
+ private:
+  int fd_;
+  DISALLOW_COPY_AND_ASSIGN(ScopedProcSelfTask);
+};
+
+TEST(ThreadHelpers, IsSingleThreadedBasic) {
+  ScopedProcSelfTask task;
+  ASSERT_TRUE(ThreadHelpers::IsSingleThreaded(task.fd()));
+
+  base::Thread thread("sandbox_tests");
+  ASSERT_TRUE(thread.Start());
+  ASSERT_FALSE(ThreadHelpers::IsSingleThreaded(task.fd()));
+}
+
+TEST(ThreadHelpers, IsSingleThreadedIterated) {
+  ScopedProcSelfTask task;
+  ASSERT_TRUE(ThreadHelpers::IsSingleThreaded(task.fd()));
+
+  // Iterate to check for race conditions.
+  for (int i = 0; i < GetRaceTestIterations(); ++i) {
+    base::Thread thread("sandbox_tests");
+    ASSERT_TRUE(thread.Start());
+    ASSERT_FALSE(ThreadHelpers::IsSingleThreaded(task.fd()));
+  }
+}
+
+TEST(ThreadHelpers, IsSingleThreadedStartAndStop) {
+  ScopedProcSelfTask task;
+  ASSERT_TRUE(ThreadHelpers::IsSingleThreaded(task.fd()));
+
+  base::Thread thread("sandbox_tests");
+  // This is testing for a race condition, so iterate.
+  // Manually, this has been tested with more that 1M iterations.
+  for (int i = 0; i < GetRaceTestIterations(); ++i) {
+    ASSERT_TRUE(thread.Start());
+    ASSERT_FALSE(ThreadHelpers::IsSingleThreaded(task.fd()));
+
+    ASSERT_TRUE(ThreadHelpers::StopThreadAndWatchProcFS(task.fd(), &thread));
+    ASSERT_TRUE(ThreadHelpers::IsSingleThreaded(task.fd()));
+    ASSERT_EQ(1, base::GetNumberOfThreads(base::GetCurrentProcessHandle()));
+  }
+}
+
+}  // namespace
+
+}  // namespace sandbox