Backed out 3 changesets (bug 1538279) for mass test failures. CLOSED …

…TREE

Backed out changeset af07f58d18cc (bug 1538279)
Backed out changeset 508ee4cf9ea2 (bug 1538279)
Backed out changeset 6f2e7c819c11 (bug 1538279)

browser/app/nsBrowserApp.cpp

@@ -212,14 +212,14 @@ static int do_main(int argc, char* argv[], char* envp[]) {
   return gBootstrap->XRE_main(argc, argv, config);
 }
 
-static nsresult InitXPCOMGlue(LibLoadingStrategy aLibLoadingStrategy) {
+static nsresult InitXPCOMGlue() {
   UniqueFreePtr<char> exePath = BinaryPath::Get();
   if (!exePath) {
     Output("Couldn't find the application directory.\n");
     return NS_ERROR_FAILURE;
   }
 
-  gBootstrap = mozilla::GetBootstrap(exePath.get(), aLibLoadingStrategy);
+  gBootstrap = mozilla::GetBootstrap(exePath.get());
   if (!gBootstrap) {
     Output("Couldn't load XPCOM.\n");
     return NS_ERROR_FAILURE;
@@ -255,10 +255,7 @@ int main(int argc, char* argv[], char* envp[]) {
     }
 #  endif
 
-    // Don't bother doing a ReadAhead if we're not in the parent process.
-    // What we need from the library should already be in the system file
-    // cache.
-    nsresult rv = InitXPCOMGlue(LibLoadingStrategy::NoReadAhead);
+    nsresult rv = InitXPCOMGlue();
     if (NS_FAILED(rv)) {
       return 255;
     }
@@ -280,7 +277,7 @@ int main(int argc, char* argv[], char* envp[]) {
   DllBlocklist_Initialize(gBlocklistInitFlags);
 #endif
 
-  nsresult rv = InitXPCOMGlue(LibLoadingStrategy::ReadAhead);
+  nsresult rv = InitXPCOMGlue();
   if (NS_FAILED(rv)) {
     return 255;
   }

modules/libjar/nsZipArchive.cpp

@@ -20,7 +20,6 @@
 #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"
@@ -651,8 +650,32 @@ 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);
-    mozilla::MaybePrefetchMemory(const_cast<uint8_t *>(startp),
-                                 readaheadLength);
+    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
+    }
   } else {
     for (buf = endp - ZIPEND_SIZE; buf > startp; buf--) {
       if (xtolong(buf) == ENDSIG) {

mozglue/android/APKOpen.cpp

@@ -196,8 +196,7 @@ static mozglueresult loadGeckoLibs() {
   getrusage(RUSAGE_THREAD, &usage1_thread);
   getrusage(RUSAGE_SELF, &usage1);
 
-  gBootstrap = GetBootstrap(getUnpackedLibraryName("libxul.so").get(),
-                            LibLoadingStrategy::ReadAhead);
+  gBootstrap = GetBootstrap(getUnpackedLibraryName("libxul.so").get());
   if (!gBootstrap) {
     __android_log_print(ANDROID_LOG_ERROR, "GeckoLibLoad",
                         "Couldn't get a handle to libxul!");

toolkit/xre/Bootstrap.h

@@ -128,11 +128,6 @@ class Bootstrap {
 #endif
 };
 
-enum class LibLoadingStrategy {
-  NoReadAhead,
-  ReadAhead,
-};
-
 /**
  * Creates and returns the singleton instnace of the bootstrap object.
  * @param `b` is an outparam. We use a parameter and not a return value
@@ -142,15 +137,12 @@ enum class LibLoadingStrategy {
  */
 #ifdef XPCOM_GLUE
 typedef void (*GetBootstrapType)(Bootstrap::UniquePtr&);
-Bootstrap::UniquePtr GetBootstrap(
-    const char* aXPCOMFile = nullptr,
-    LibLoadingStrategy aLibLoadingStrategy = LibLoadingStrategy::NoReadAhead);
+Bootstrap::UniquePtr GetBootstrap(const char* aXPCOMFile = nullptr);
 #else
 extern "C" NS_EXPORT void NS_FROZENCALL
 XRE_GetBootstrap(Bootstrap::UniquePtr& b);
 
-inline Bootstrap::UniquePtr GetBootstrap(
-    const char* aXPCOMFile = nullptr) {
+inline Bootstrap::UniquePtr GetBootstrap(const char* aXPCOMFile = nullptr) {
   Bootstrap::UniquePtr bootstrap;
   XRE_GetBootstrap(bootstrap);
   return bootstrap;

xpcom/glue/FileUtils.cpp

@@ -13,7 +13,6 @@
 #include "private/pprio.h"
 #include "prmem.h"
 #include "mozilla/Assertions.h"
-#include "mozilla/MemUtils.h"
 
 #if defined(XP_MACOSX)
 #  include <fcntl.h>
@@ -33,8 +32,7 @@
 #  include <sys/types.h>
 #  include <sys/stat.h>
 #elif defined(XP_WIN)
-#  include <nsWindowsHelpers.h>
-#  include <mozilla/ScopeExit.h>
+#  include <windows.h>
 #endif
 
 // Functions that are not to be used in standalone glue must be implemented
@@ -357,37 +355,7 @@ void mozilla::ReadAheadLib(mozilla::pathstr_t aFilePath) {
     return;
   }
 #if defined(XP_WIN)
-  nsAutoHandle fd(CreateFileW(aFilePath, GENERIC_READ,
-                              FILE_SHARE_READ, nullptr, OPEN_EXISTING,
-                              FILE_FLAG_SEQUENTIAL_SCAN, nullptr));
-  if (!fd) {
-    return;
-  }
-  LARGE_INTEGER fileSize = {};
-  BOOL success = GetFileSizeEx(fd, &fileSize);
-  if (!success || !fileSize.QuadPart ||
-      fileSize.QuadPart > std::numeric_limits<size_t>::max()) {
-    return;
-  }
-
-  nsAutoHandle mapping(CreateFileMapping(fd, nullptr,
-                                         SEC_IMAGE | PAGE_READONLY,
-                                         0, 0, nullptr));
-
-  if (!mapping) {
-    return;
-  }
-
-  PVOID data = MapViewOfFile(mapping, FILE_MAP_READ, 0, 0, 0);
-  auto guard = MakeScopeExit([=]() { UnmapViewOfFile(data); });
-
-  if (!MaybePrefetchMemory((uint8_t*)data, (size_t)fileSize.QuadPart)) {
-    volatile uint8_t read = 0;
-    for(size_t i = 0; i < (size_t)fileSize.QuadPart; i += 4096) {
-      read += ((uint8_t*)data)[i];
-    }
-  }
-
+  ReadAheadFile(aFilePath);
 #elif defined(LINUX) && !defined(ANDROID)
   int fd = open(aFilePath, O_RDONLY);
   if (fd < 0) {

xpcom/glue/moz.build

@@ -8,5 +8,4 @@ DIRS += ['standalone']
 
 EXPORTS.mozilla += [
     'FileUtils.h',
-    'MemUtils.h',
 ]

xpcom/glue/objs.mozbuild

@@ -6,7 +6,6 @@
 
 xpcom_glue_src_lcppsrcs = [
     'FileUtils.cpp',
-    'MemUtils.cpp',
     'XREAppData.cpp',
 ]
 

xpcom/glue/standalone/moz.build

@@ -6,7 +6,6 @@
 
 SOURCES += [
     '../FileUtils.cpp',
-    '../MemUtils.cpp',
     'nsXPCOMGlue.cpp',
 ]
 

xpcom/glue/standalone/nsXPCOMGlue.cpp

@@ -123,12 +123,10 @@ static void AppendDependentLib(LibHandleType aLibHandle) {
   sTop = d;
 }
 
-static bool ReadDependentCB(pathstr_t aDependentLib,
-                            LibLoadingStrategy aLibLoadingStrategy) {
+static bool ReadDependentCB(pathstr_t aDependentLib) {
 #ifndef MOZ_LINKER
-  if (aLibLoadingStrategy == LibLoadingStrategy::ReadAhead) {
-    ReadAheadLib(aDependentLib);
-  }
+  // We do this unconditionally because of data in bug 771745
+  ReadAheadLib(aDependentLib);
 #endif
   LibHandleType libHandle = GetLibHandle(aDependentLib);
   if (libHandle) {
@@ -139,12 +137,11 @@ static bool ReadDependentCB(pathstr_t aDependentLib,
 }
 
 #ifdef XP_WIN
-static bool ReadDependentCB(const char* aDependentLib,
-                            LibLoadingStrategy aLibLoadingStrategy) {
+static bool ReadDependentCB(const char* aDependentLib) {
   wchar_t wideDependentLib[MAX_PATH];
   MultiByteToWideChar(CP_UTF8, 0, aDependentLib, -1, wideDependentLib,
                       MAX_PATH);
-  return ReadDependentCB(wideDependentLib, aLibLoadingStrategy);
+  return ReadDependentCB(wideDependentLib);
 }
 
 inline FILE* TS_tfopen(const char* path, const wchar_t* mode) {
@@ -201,10 +198,9 @@ static const char* ns_strrpbrk(const char* string, const char* strCharSet) {
 }
 #endif
 
-static nsresult XPCOMGlueLoad(const char* aXPCOMFile,
-                              LibLoadingStrategy aLibLoadingStrategy) {
+static nsresult XPCOMGlueLoad(const char* aXPCOMFile) {
 #ifdef MOZ_LINKER
-  if (!ReadDependentCB(aXPCOMFile, aLibLoadingStrategy)) {
+  if (!ReadDependentCB(aXPCOMFile)) {
     return NS_ERROR_FAILURE;
   }
 #else
@@ -300,7 +296,7 @@ static nsresult XPCOMGlueLoad(const char* aXPCOMFile,
     }
 
     strcpy(cursor, buffer);
-    if (!ReadDependentCB(xpcomDir, aLibLoadingStrategy)) {
+    if (!ReadDependentCB(xpcomDir)) {
       XPCOMGlueUnload();
       return NS_ERROR_FAILURE;
     }
@@ -346,8 +342,7 @@ class GSliceInit {
 
 namespace mozilla {
 
-Bootstrap::UniquePtr GetBootstrap(const char* aXPCOMFile,
-                                  LibLoadingStrategy aLibLoadingStrategy) {
+Bootstrap::UniquePtr GetBootstrap(const char* aXPCOMFile) {
 #ifdef MOZ_GSLICE_INIT
   GSliceInit gSliceInit;
 #endif
@@ -368,7 +363,7 @@ Bootstrap::UniquePtr GetBootstrap(const char* aXPCOMFile,
   memcpy(file.get(), aXPCOMFile, base_len);
   memcpy(file.get() + base_len, XPCOM_DLL, sizeof(XPCOM_DLL));
 
-  if (NS_FAILED(XPCOMGlueLoad(file.get(), aLibLoadingStrategy))) {
+  if (NS_FAILED(XPCOMGlueLoad(file.get()))) {
     return nullptr;
   }