Linux sandbox: report TSYNC status in chrome://sandbox

content/common/sandbox_linux/sandbox_seccomp_bpf_linux.h

 // 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.
 
 #ifndef CONTENT_COMMON_SANDBOX_LINUX_SANDBOX_SECCOMP_BPF_LINUX_H_
 #define CONTENT_COMMON_SANDBOX_LINUX_SANDBOX_SECCOMP_BPF_LINUX_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 14 matching lines @@
 class SandboxSeccompBPF {
  public:
   // This is the API to enable a seccomp-bpf sandbox for content/
   // process-types:
   // Is the sandbox globally enabled, can anything use it at all ?
   // This looks at global command line flags to see if the sandbox
   // should be enabled at all.
   static bool IsSeccompBPFDesired();
   // Should the sandbox be enabled for process_type ?
   static bool ShouldEnableSeccompBPF(const std::string& process_type);
-  // Check if the kernel supports this sandbox. It's useful to "prewarm"
-  // this, part of the result will be cached.
+  // Check if the kernel supports seccomp-bpf.
   static bool SupportsSandbox();
+  // Check if the kernel supports TSYNC (thread synchronization) with seccomp.
+  static bool SupportsSandboxWithTsync();
   // Start the sandbox and apply the policy for process_type, depending on
   // command line switches.
   static bool StartSandbox(const std::string& process_type,
                            base::ScopedFD proc_task_fd);
 
   // This is the API to enable a seccomp-bpf sandbox by using an
   // external policy.
   static bool StartSandboxWithExternalPolicy(
       scoped_ptr<sandbox::bpf_dsl::Policy> policy,
       base::ScopedFD proc_task_fd);
   // The "baseline" policy can be a useful base to build a sandbox policy.
   static scoped_ptr<sandbox::bpf_dsl::Policy> GetBaselinePolicy();
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(SandboxSeccompBPF);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_SANDBOX_LINUX_SANDBOX_SECCOMP_BPF_LINUX_H_