Revert 126020 - Experiment for updating the tcmalloc chromium branch to r144 (gperftools 2.0).

third_party/tcmalloc/chromium/src/libc_override_osx.h

-// Copyright (c) 2011, Google Inc.
-// All rights reserved.
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// ---
-// Author: Craig Silverstein <opensource@google.com>
-//
-// Used to override malloc routines on OS X systems.  We use the
-// malloc-zone functionality built into OS X to register our malloc
-// routine.
-//
-// 1) We used to use the normal 'override weak libc malloc/etc'
-// technique for OS X.  This is not optimal because mach does not
-// support the 'alias' attribute, so we had to have forwarding
-// functions.  It also does not work very well with OS X shared
-// libraries (dylibs) -- in general, the shared libs don't use
-// tcmalloc unless run with the DYLD_FORCE_FLAT_NAMESPACE envvar.
-//
-// 2) Another approach would be to use an interposition array:
-//      static const interpose_t interposers[] __attribute__((section("__DATA, __interpose"))) = {
-//        { (void *)tc_malloc, (void *)malloc },
-//        { (void *)tc_free, (void *)free },
-//      };
-// This requires the user to set the DYLD_INSERT_LIBRARIES envvar, so
-// is not much better.
-//
-// 3) Registering a new malloc zone avoids all these issues:
-//  http://www.opensource.apple.com/source/Libc/Libc-583/include/malloc/malloc.h
-//  http://www.opensource.apple.com/source/Libc/Libc-583/gen/malloc.c
-// If we make tcmalloc the default malloc zone (undocumented but
-// possible) then all new allocs use it, even those in shared
-// libraries.  Allocs done before tcmalloc was installed, or in libs
-// that aren't using tcmalloc for some reason, will correctly go
-// through the malloc-zone interface when free-ing, and will pick up
-// the libc free rather than tcmalloc free.  So it should "never"
-// cause a crash (famous last words).
-//
-// 4) The routines one must define for one's own malloc have changed
-// between OS X versions.  This requires some hoops on our part, but
-// is only really annoying when it comes to posix_memalign.  The right
-// behavior there depends on what OS version tcmalloc was compiled on,
-// but also what OS version the program is running on.  For now, we
-// punt and don't implement our own posix_memalign.  Apps that really
-// care can use tc_posix_memalign directly.
-
-#ifndef TCMALLOC_LIBC_OVERRIDE_OSX_INL_H_
-#define TCMALLOC_LIBC_OVERRIDE_OSX_INL_H_
-
-#include <config.h>
-#ifdef HAVE_FEATURES_H
-#include <features.h>
-#endif
-#include <gperftools/tcmalloc.h>
-
-#if !defined(__APPLE__)
-# error libc_override_glibc-osx.h is for OS X distributions only.
-#endif
-
-#include <AvailabilityMacros.h>
-#include <malloc/malloc.h>
-
-// from AvailabilityMacros.h
-#if defined(MAC_OS_X_VERSION_10_6) && \
-    MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_6
-extern "C" {
-  // This function is only available on 10.6 (and later) but the
-  // LibSystem headers do not use AvailabilityMacros.h to handle weak
-  // importing automatically.  This prototype is a copy of the one in
-  // <malloc/malloc.h> with the WEAK_IMPORT_ATTRBIUTE added.
-  extern malloc_zone_t *malloc_default_purgeable_zone(void)
-      WEAK_IMPORT_ATTRIBUTE;
-}
-#endif
-
-// We need to provide wrappers around all the libc functions.
-namespace {
-size_t mz_size(malloc_zone_t* zone, const void* ptr) {
-  if (MallocExtension::instance()->GetOwnership(ptr) != MallocExtension::kOwned)
-    return 0;  // malloc_zone semantics: return 0 if we don't own the memory
-
-  // TODO(csilvers): change this method to take a const void*, one day.
-  return MallocExtension::instance()->GetAllocatedSize(const_cast<void*>(ptr));
-}
-
-void* mz_malloc(malloc_zone_t* zone, size_t size) {
-  return tc_malloc(size);
-}
-
-void* mz_calloc(malloc_zone_t* zone, size_t num_items, size_t size) {
-  return tc_calloc(num_items, size);
-}
-
-void* mz_valloc(malloc_zone_t* zone, size_t size) {
-  return tc_valloc(size);
-}
-
-void mz_free(malloc_zone_t* zone, void* ptr) {
-  return tc_free(ptr);
-}
-
-void* mz_realloc(malloc_zone_t* zone, void* ptr, size_t size) {
-  return tc_realloc(ptr, size);
-}
-
-void* mz_memalign(malloc_zone_t* zone, size_t align, size_t size) {
-  return tc_memalign(align, size);
-}
-
-void mz_destroy(malloc_zone_t* zone) {
-  // A no-op -- we will not be destroyed!
-}
-
-// malloc_introspection callbacks.  I'm not clear on what all of these do.
-kern_return_t mi_enumerator(task_t task, void *,
-                            unsigned type_mask, vm_address_t zone_address,
-                            memory_reader_t reader,
-                            vm_range_recorder_t recorder) {
-  // Should enumerate all the pointers we have.  Seems like a lot of work.
-  return KERN_FAILURE;
-}
-
-size_t mi_good_size(malloc_zone_t *zone, size_t size) {
-  // I think it's always safe to return size, but we maybe could do better.
-  return size;
-}
-
-boolean_t mi_check(malloc_zone_t *zone) {
-  return MallocExtension::instance()->VerifyAllMemory();
-}
-
-void mi_print(malloc_zone_t *zone, boolean_t verbose) {
-  int bufsize = 8192;
-  if (verbose)
-    bufsize = 102400;   // I picked this size arbitrarily
-  char* buffer = new char[bufsize];
-  MallocExtension::instance()->GetStats(buffer, bufsize);
-  fprintf(stdout, "%s", buffer);
-  delete[] buffer;
-}
-
-void mi_log(malloc_zone_t *zone, void *address) {
-  // I don't think we support anything like this
-}
-
-void mi_force_lock(malloc_zone_t *zone) {
-  // Hopefully unneeded by us!
-}
-
-void mi_force_unlock(malloc_zone_t *zone) {
-  // Hopefully unneeded by us!
-}
-
-void mi_statistics(malloc_zone_t *zone, malloc_statistics_t *stats) {
-  // TODO(csilvers): figure out how to fill these out
-  stats->blocks_in_use = 0;
-  stats->size_in_use = 0;
-  stats->max_size_in_use = 0;
-  stats->size_allocated = 0;
-}
-
-boolean_t mi_zone_locked(malloc_zone_t *zone) {
-  return false;  // Hopefully unneeded by us!
-}
-
-}  // unnamed namespace
-
-// OS X doesn't have pvalloc, cfree, malloc_statc, etc, so we can just
-// define our own. :-)  OS X supplies posix_memalign in some versions
-// but not others, either strongly or weakly linked, in a way that's
-// difficult enough to code to correctly, that I just don't try to
-// support either memalign() or posix_memalign().  If you need them
-// and are willing to code to tcmalloc, you can use tc_posix_memalign().
-extern "C" {
-  void  cfree(void* p)                   { tc_cfree(p);               }
-  void* pvalloc(size_t s)                { return tc_pvalloc(s);      }
-  void malloc_stats(void)                { tc_malloc_stats();         }
-  int mallopt(int cmd, int v)            { return tc_mallopt(cmd, v); }
-  // No struct mallinfo on OS X, so don't define mallinfo().
-  // An alias for malloc_size(), which OS X defines.
-  size_t malloc_usable_size(void* p)     { return tc_malloc_size(p); }
-}  // extern "C"
-
-static void ReplaceSystemAlloc() {
-  static malloc_introspection_t tcmalloc_introspection;
-  memset(&tcmalloc_introspection, 0, sizeof(tcmalloc_introspection));
-
-  tcmalloc_introspection.enumerator = &mi_enumerator;
-  tcmalloc_introspection.good_size = &mi_good_size;
-  tcmalloc_introspection.check = &mi_check;
-  tcmalloc_introspection.print = &mi_print;
-  tcmalloc_introspection.log = &mi_log;
-  tcmalloc_introspection.force_lock = &mi_force_lock;
-  tcmalloc_introspection.force_unlock = &mi_force_unlock;
-
-  static malloc_zone_t tcmalloc_zone;
-  memset(&tcmalloc_zone, 0, sizeof(malloc_zone_t));
-
-  // Start with a version 4 zone which is used for OS X 10.4 and 10.5.
-  tcmalloc_zone.version = 4;
-  tcmalloc_zone.zone_name = "tcmalloc";
-  tcmalloc_zone.size = &mz_size;
-  tcmalloc_zone.malloc = &mz_malloc;
-  tcmalloc_zone.calloc = &mz_calloc;
-  tcmalloc_zone.valloc = &mz_valloc;
-  tcmalloc_zone.free = &mz_free;
-  tcmalloc_zone.realloc = &mz_realloc;
-  tcmalloc_zone.destroy = &mz_destroy;
-  tcmalloc_zone.batch_malloc = NULL;
-  tcmalloc_zone.batch_free = NULL;
-  tcmalloc_zone.introspect = &tcmalloc_introspection;
-
-  // from AvailabilityMacros.h
-#if defined(MAC_OS_X_VERSION_10_6) && \
-    MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_6
-  // Switch to version 6 on OSX 10.6 to support memalign.
-  tcmalloc_zone.version = 6;
-  tcmalloc_zone.free_definite_size = NULL;
-  tcmalloc_zone.memalign = &mz_memalign;
-  tcmalloc_introspection.zone_locked = &mi_zone_locked;
-
-  // Request the default purgable zone to force its creation. The
-  // current default zone is registered with the purgable zone for
-  // doing tiny and small allocs.  Sadly, it assumes that the default
-  // zone is the szone implementation from OS X and will crash if it
-  // isn't.  By creating the zone now, this will be true and changing
-  // the default zone won't cause a problem.  This only needs to
-  // happen when actually running on OS X 10.6 and higher (note the
-  // ifdef above only checks if we were *compiled* with 10.6 or
-  // higher; at runtime we have to check if this symbol is defined.)
-  if (malloc_default_purgeable_zone) {
-    malloc_default_purgeable_zone();
-  }
-#endif
-
-  // Register the tcmalloc zone. At this point, it will not be the
-  // default zone.
-  malloc_zone_register(&tcmalloc_zone);
-
-  // Unregister and reregister the default zone.  Unregistering swaps
-  // the specified zone with the last one registered which for the
-  // default zone makes the more recently registered zone the default
-  // zone.  The default zone is then re-registered to ensure that
-  // allocations made from it earlier will be handled correctly.
-  // Things are not guaranteed to work that way, but it's how they work now.
-  malloc_zone_t *default_zone = malloc_default_zone();
-  malloc_zone_unregister(default_zone);
-  malloc_zone_register(default_zone);
-}
-
-#endif  // TCMALLOC_LIBC_OVERRIDE_OSX_INL_H_