Commit ebd6ab40 authored by Doug Thayer's avatar Doug Thayer
Browse files

Bug 1538279 - Extract nsZipArchive's madvise and similar to a helper r=glandium,froydnj 

This is just to make it simpler to use PrefetchVirtualMemory in subsequent patches.

Differential Revision: https://phabricator.services.mozilla.com/D26016

--HG--
extra : moz-landing-system : lando
parent 28d488a2

modules/libjar/nsZipArchive.cpp

+3 −26
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ 
#include "plstr.h"

#include "mozilla/Attributes.h"

#include "mozilla/Logging.h"

#include "mozilla/MemUtils.h"

#include "mozilla/UniquePtrExtensions.h"

#include "stdlib.h"

#include "nsDirectoryService.h"
@@ -650,32 +651,8 @@ nsresult nsZipArchive::BuildFileList(PRFileDesc *aFd) { 
      xtolong(startp + centralOffset) == CENTRALSIG) {

    // Success means optimized jar layout from bug 559961 is in effect

    uint32_t readaheadLength = xtolong(startp);

    if (readaheadLength) {

#if defined(XP_SOLARIS)

      posix_madvise(const_cast<uint8_t *>(startp), readaheadLength,

                    POSIX_MADV_WILLNEED);

#elif defined(XP_UNIX)

      madvise(const_cast<uint8_t *>(startp), readaheadLength, MADV_WILLNEED);

#elif defined(XP_WIN)

      static auto prefetchVirtualMemory =

          reinterpret_cast<BOOL(WINAPI *)(HANDLE, ULONG_PTR, PVOID, ULONG)>(

              GetProcAddress(GetModuleHandle(L"kernel32.dll"),

                             "PrefetchVirtualMemory"));

      if (prefetchVirtualMemory) {

        // 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 = const_cast<uint8_t *>(startp);

        entry.NumberOfBytes = readaheadLength;

        prefetchVirtualMemory(GetCurrentProcess(), 1, &entry, 0);

      }

#endif

    }

    mozilla::MaybePrefetchMemory(const_cast<uint8_t *>(startp),

                                 readaheadLength);

  } else {

    for (buf = endp - ZIPEND_SIZE; buf > startp; buf--) {

      if (xtolong(buf) == ENDSIG) {

xpcom/glue/MemUtils.cpp

0 → 100644
+50 −0
Original line number Diff line number Diff line 
/* -*- 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>

#else

#  include <sys/mman.h>

#endif



bool mozilla::MaybePrefetchMemory(uint8_t* aStart, size_t aNumBytes) {

  if (aNumBytes == 0) {

    return true;

  }



#if defined(XP_SOLARIS)

  posix_madvise(aStart, aNumBytes, POSIX_MADV_WILLNEED);

  return true;

#elif defined(XP_UNIX)

  madvise(aStart, aNumBytes, MADV_WILLNEED);

  return true;

#elif defined(XP_WIN)

  static auto prefetchVirtualMemory =

      reinterpret_cast<BOOL(WINAPI*)(HANDLE, ULONG_PTR, PVOID, ULONG)>(

          GetProcAddress(GetModuleHandleW(L"kernel32.dll"),

                         "PrefetchVirtualMemory"));



  if (prefetchVirtualMemory) {

    // 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;

    prefetchVirtualMemory(GetCurrentProcess(), 1, &entry, 0);

    return true;

  }

  return false;

#else

  return false;

#endif

}

xpcom/glue/MemUtils.h

0 → 100644
+19 −0
Original line number Diff line number Diff line 
/* -*- 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/. */



#ifndef mozilla_MemUtils_h

#define mozilla_MemUtils_h



#include <stddef.h>

#include <stdint.h>



namespace mozilla {



bool MaybePrefetchMemory(uint8_t* aStart, size_t aNumBytes);



}  // namespace mozilla



#endif

xpcom/glue/moz.build

+1 −0
Original line number Diff line number Diff line
@@ -8,4 +8,5 @@ DIRS += ['standalone'] 


EXPORTS.mozilla += [

    'FileUtils.h',

    'MemUtils.h',

]

xpcom/glue/objs.mozbuild

+1 −0
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ 


xpcom_glue_src_lcppsrcs = [

    'FileUtils.cpp',

    'MemUtils.cpp',

    'XREAppData.cpp',

]