1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
5 * You can obtain one at http://mozilla.org/MPL/2.0/. */
7 #ifndef mozilla_PreallocatedProcessManager_h
8 #define mozilla_PreallocatedProcessManager_h
10 #include "base/basictypes.h"
11 #include "mozilla/AlreadyAddRefed.h"
12 #include "nsStringFwd.h"
20 * This class manages a ContentParent that it starts up ahead of any particular
21 * need. You can then call Take() to get this process and use it. Since we
22 * already started it up, it should be ready for use faster than if you'd
23 * created the process when you needed it.
25 * This class watches the dom.ipc.processPrelaunch.enabled pref. If it changes
26 * from false to true, it preallocates a process. If it changes from true to
27 * false, it kills the preallocated process, if any.
29 * We don't expect this pref to flip between true and false in production, but
30 * flipping the pref is important for tests.
32 class PreallocatedProcessManagerImpl
;
34 class PreallocatedProcessManager final
{
35 typedef mozilla::dom::ContentParent ContentParent
;
38 static PreallocatedProcessManagerImpl
* GetPPMImpl();
40 static bool Enabled();
43 * Before first paint we don't want to allocate any processes in the
44 * background. To avoid that, the PreallocatedProcessManager won't start up
45 * any processes while there is a blocker active.
47 static void AddBlocker(const nsACString
& aRemoteType
, ContentParent
* aParent
);
48 static void RemoveBlocker(const nsACString
& aRemoteType
,
49 ContentParent
* aParent
);
52 * Take a preallocated process, if we have one. If we don't have a
53 * preallocated process to return, this returns null.
55 * If we use a preallocated process, it will schedule the start of
56 * another on Idle (AllocateOnIdle()).
58 static already_AddRefed
<ContentParent
> Take(const nsACString
& aRemoteType
);
61 * Note that a process was shut down, and should no longer be tracked as a
62 * preallocated process.
64 static void Erase(ContentParent
* aParent
);
67 PreallocatedProcessManager();
68 DISALLOW_EVIL_CONSTRUCTORS(PreallocatedProcessManager
);
71 } // namespace mozilla
73 #endif // defined mozilla_PreallocatedProcessManager_h