mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-10-09 19:35:51 +00:00
5f3d1ecd2e
Temporarily just sidestep the issue in bug 1546498 (crash with latest SDK on startup in Windows 7) by just continuing to use the old method in Windows 7. We saw no wins in telemetry for Windows 7 anyway, so we should investigate why that is, and why we see a mysterious crash in the fallback code, in a followup bug. Differential Revision: https://phabricator.services.mozilla.com/D29239 --HG-- extra : moz-landing-system : lando
68 lines
1.9 KiB
C++
68 lines
1.9 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
|
|
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
#include "mozilla/MemUtils.h"
|
|
|
|
#if defined(XP_WIN)
|
|
# include <windows.h>
|
|
# include "mozilla/Maybe.h"
|
|
#else
|
|
# include <sys/mman.h>
|
|
#endif
|
|
|
|
#if defined(XP_WIN)
|
|
typedef BOOL(WINAPI* PrefetchVirtualMemoryFn)(HANDLE, ULONG_PTR, PVOID, ULONG);
|
|
|
|
static mozilla::Maybe<PrefetchVirtualMemoryFn> sPrefetchVirtualMemory;
|
|
|
|
void MaybeInitPrefetchVirtualMemory() {
|
|
if (sPrefetchVirtualMemory.isNothing()) {
|
|
sPrefetchVirtualMemory.emplace(
|
|
reinterpret_cast<PrefetchVirtualMemoryFn>(GetProcAddress(
|
|
GetModuleHandleW(L"kernel32.dll"), "PrefetchVirtualMemory")));
|
|
}
|
|
}
|
|
#endif
|
|
|
|
bool mozilla::CanPrefetchMemory() {
|
|
#if defined(XP_SOLARIS) || defined(XP_UNIX)
|
|
return true;
|
|
#elif defined(XP_WIN)
|
|
MaybeInitPrefetchVirtualMemory();
|
|
return *sPrefetchVirtualMemory;
|
|
#else
|
|
return false;
|
|
#endif
|
|
}
|
|
|
|
void mozilla::PrefetchMemory(uint8_t* aStart, size_t aNumBytes) {
|
|
if (aNumBytes == 0) {
|
|
return;
|
|
}
|
|
|
|
#if defined(XP_SOLARIS)
|
|
posix_madvise(aStart, aNumBytes, POSIX_MADV_WILLNEED);
|
|
#elif defined(XP_UNIX)
|
|
madvise(aStart, aNumBytes, MADV_WILLNEED);
|
|
#elif defined(XP_WIN)
|
|
MaybeInitPrefetchVirtualMemory();
|
|
if (*sPrefetchVirtualMemory) {
|
|
// Normally, we'd use WIN32_MEMORY_RANGE_ENTRY, but that requires
|
|
// a different _WIN32_WINNT value before including windows.h, but
|
|
// that causes complications with unified sources. It's a simple
|
|
// enough struct anyways.
|
|
struct {
|
|
PVOID VirtualAddress;
|
|
SIZE_T NumberOfBytes;
|
|
} entry;
|
|
entry.VirtualAddress = aStart;
|
|
entry.NumberOfBytes = aNumBytes;
|
|
(*sPrefetchVirtualMemory)(GetCurrentProcess(), 1, &entry, 0);
|
|
return;
|
|
}
|
|
#endif
|
|
}
|