1/*
2 * Copyright (C) 2017 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "WasmMachineThreads.h"
28
29#if ENABLE(WEBASSEMBLY)
30
31#include "MachineStackMarker.h"
32#include <wtf/NeverDestroyed.h>
33#include <wtf/ThreadMessage.h>
34#include <wtf/threads/Signals.h>
35
36namespace JSC { namespace Wasm {
37
38
39inline MachineThreads& wasmThreads()
40{
41 static LazyNeverDestroyed<MachineThreads> threads;
42 static std::once_flag once;
43 std::call_once(once, [] {
44 threads.construct();
45 });
46
47 return threads;
48}
49
50void startTrackingCurrentThread()
51{
52 wasmThreads().addCurrentThread();
53}
54
55void resetInstructionCacheOnAllThreads()
56{
57 auto locker = holdLock(wasmThreads().getLock());
58 for (auto& thread : wasmThreads().threads(locker)) {
59 sendMessage(thread.get(), [] (const PlatformRegisters&) {
60 // It's likely that the signal handler will already reset the instruction cache but we might as well be sure.
61 WTF::crossModifyingCodeFence();
62 });
63 }
64}
65
66
67} } // namespace JSC::Wasm
68
69#endif // ENABLE(WEBASSEMBLY)
70