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-rw-r--r--memory/build/zone.c377
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diff --git a/memory/build/zone.c b/memory/build/zone.c
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+++ b/memory/build/zone.c
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+/* -*- 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 "mozmemory_wrap.h"
+
+#include <stdlib.h>
+#include <mach/mach_types.h>
+#include "mozilla/Assertions.h"
+
+// Malloc implementation functions are MOZ_MEMORY_API, and jemalloc
+// specific functions MOZ_JEMALLOC_API; see mozmemory_wrap.h
+
+#define MALLOC_DECL(name, return_type, ...) \
+ MOZ_MEMORY_API return_type name##_impl(__VA_ARGS__);
+#define MALLOC_FUNCS MALLOC_FUNCS_MALLOC
+#include "malloc_decls.h"
+
+#define MALLOC_DECL(name, return_type, ...) \
+ MOZ_JEMALLOC_API return_type name##_impl(__VA_ARGS__);
+#define MALLOC_FUNCS MALLOC_FUNCS_JEMALLOC
+#include "malloc_decls.h"
+
+// Definitions of the following structs in malloc/malloc.h might be too old
+// for the built binary to run on newer versions of OSX. So use the newest
+// possible version of those structs.
+
+typedef struct _malloc_zone_t {
+ void* reserved1;
+ void* reserved2;
+ size_t (*size)(struct _malloc_zone_t*, const void*);
+ void* (*malloc)(struct _malloc_zone_t*, size_t);
+ void* (*calloc)(struct _malloc_zone_t*, size_t, size_t);
+ void* (*valloc)(struct _malloc_zone_t*, size_t);
+ void (*free)(struct _malloc_zone_t*, void*);
+ void* (*realloc)(struct _malloc_zone_t*, void*, size_t);
+ void (*destroy)(struct _malloc_zone_t*);
+ const char* zone_name;
+ unsigned (*batch_malloc)(struct _malloc_zone_t*, size_t, void**, unsigned);
+ void (*batch_free)(struct _malloc_zone_t*, void**, unsigned);
+ struct malloc_introspection_t* introspect;
+ unsigned version;
+ void* (*memalign)(struct _malloc_zone_t*, size_t, size_t);
+ void (*free_definite_size)(struct _malloc_zone_t*, void*, size_t);
+ size_t (*pressure_relief)(struct _malloc_zone_t*, size_t);
+} malloc_zone_t;
+
+typedef struct {
+ vm_address_t address;
+ vm_size_t size;
+} vm_range_t;
+
+typedef struct malloc_statistics_t {
+ unsigned blocks_in_use;
+ size_t size_in_use;
+ size_t max_size_in_use;
+ size_t size_allocated;
+} malloc_statistics_t;
+
+typedef kern_return_t memory_reader_t(task_t, vm_address_t, vm_size_t, void**);
+
+typedef void vm_range_recorder_t(task_t, void*, unsigned type, vm_range_t*,
+ unsigned);
+
+typedef struct malloc_introspection_t {
+ kern_return_t (*enumerator)(task_t, void*, unsigned, vm_address_t,
+ memory_reader_t, vm_range_recorder_t);
+ size_t (*good_size)(malloc_zone_t*, size_t);
+ boolean_t (*check)(malloc_zone_t*);
+ void (*print)(malloc_zone_t*, boolean_t);
+ void (*log)(malloc_zone_t*, void*);
+ void (*force_lock)(malloc_zone_t*);
+ void (*force_unlock)(malloc_zone_t*);
+ void (*statistics)(malloc_zone_t*, malloc_statistics_t*);
+ boolean_t (*zone_locked)(malloc_zone_t*);
+ boolean_t (*enable_discharge_checking)(malloc_zone_t*);
+ boolean_t (*disable_discharge_checking)(malloc_zone_t*);
+ void (*discharge)(malloc_zone_t*, void*);
+#ifdef __BLOCKS__
+ void (*enumerate_discharged_pointers)(malloc_zone_t*, void (^)(void*, void*));
+#else
+ void* enumerate_unavailable_without_blocks;
+#endif
+ void (*reinit_lock)(malloc_zone_t*);
+} malloc_introspection_t;
+
+extern kern_return_t malloc_get_all_zones(task_t, memory_reader_t,
+ vm_address_t**, unsigned*);
+
+extern malloc_zone_t* malloc_default_zone(void);
+
+extern void malloc_zone_register(malloc_zone_t* zone);
+
+extern void malloc_zone_unregister(malloc_zone_t* zone);
+
+extern malloc_zone_t* malloc_default_purgeable_zone(void);
+
+extern malloc_zone_t* malloc_zone_from_ptr(const void* ptr);
+
+extern void malloc_zone_free(malloc_zone_t* zone, void* ptr);
+
+extern void* malloc_zone_realloc(malloc_zone_t* zone, void* ptr, size_t size);
+
+// The following is a OSX zone allocator implementation.
+// /!\ WARNING. It assumes the underlying malloc implementation's
+// malloc_usable_size returns 0 when the given pointer is not owned by
+// the allocator. Sadly, OSX does call zone_size with pointers not
+// owned by the allocator.
+
+static size_t zone_size(malloc_zone_t* zone, const void* ptr) {
+ return malloc_usable_size_impl(ptr);
+}
+
+static void* zone_malloc(malloc_zone_t* zone, size_t size) {
+ return malloc_impl(size);
+}
+
+static void* zone_calloc(malloc_zone_t* zone, size_t num, size_t size) {
+ return calloc_impl(num, size);
+}
+
+static void* zone_realloc(malloc_zone_t* zone, void* ptr, size_t size) {
+ if (malloc_usable_size_impl(ptr)) return realloc_impl(ptr, size);
+
+ // Sometimes, system libraries call malloc_zone_* functions with the wrong
+ // zone (e.g. CoreFoundation does). In that case, we need to find the real
+ // one. We can't call libSystem's realloc directly because we're exporting
+ // realloc from libmozglue and we'd pick that one, so we manually find the
+ // right zone and realloc with it.
+ malloc_zone_t* real_zone = malloc_zone_from_ptr(ptr);
+ // The system allocator crashes voluntarily by default when a pointer can't
+ // be traced back to a zone. Do the same.
+ MOZ_RELEASE_ASSERT(real_zone);
+ MOZ_RELEASE_ASSERT(real_zone != zone);
+ return malloc_zone_realloc(real_zone, ptr, size);
+}
+
+static void other_zone_free(malloc_zone_t* original_zone, void* ptr) {
+ // Sometimes, system libraries call malloc_zone_* functions with the wrong
+ // zone (e.g. CoreFoundation does). In that case, we need to find the real
+ // one. We can't call libSystem's free directly because we're exporting
+ // free from libmozglue and we'd pick that one, so we manually find the
+ // right zone and free with it.
+ if (!ptr) {
+ return;
+ }
+ malloc_zone_t* zone = malloc_zone_from_ptr(ptr);
+ // The system allocator crashes voluntarily by default when a pointer can't
+ // be traced back to a zone. Do the same.
+ MOZ_RELEASE_ASSERT(zone);
+ MOZ_RELEASE_ASSERT(zone != original_zone);
+ return malloc_zone_free(zone, ptr);
+}
+
+static void zone_free(malloc_zone_t* zone, void* ptr) {
+ if (malloc_usable_size_impl(ptr)) {
+ free_impl(ptr);
+ return;
+ }
+ other_zone_free(zone, ptr);
+}
+
+static void zone_free_definite_size(malloc_zone_t* zone, void* ptr,
+ size_t size) {
+ size_t current_size = malloc_usable_size_impl(ptr);
+ if (current_size) {
+ MOZ_ASSERT(current_size == size);
+ free_impl(ptr);
+ return;
+ }
+ other_zone_free(zone, ptr);
+}
+
+static void* zone_memalign(malloc_zone_t* zone, size_t alignment, size_t size) {
+ void* ptr;
+ if (posix_memalign_impl(&ptr, alignment, size) == 0) return ptr;
+ return NULL;
+}
+
+static void* zone_valloc(malloc_zone_t* zone, size_t size) {
+ return valloc_impl(size);
+}
+
+static void zone_destroy(malloc_zone_t* zone) {
+ // This function should never be called.
+ MOZ_CRASH();
+}
+
+static unsigned zone_batch_malloc(malloc_zone_t* zone, size_t size,
+ void** results, unsigned num_requested) {
+ unsigned i;
+
+ for (i = 0; i < num_requested; i++) {
+ results[i] = malloc_impl(size);
+ if (!results[i]) break;
+ }
+
+ return i;
+}
+
+static void zone_batch_free(malloc_zone_t* zone, void** to_be_freed,
+ unsigned num_to_be_freed) {
+ unsigned i;
+
+ for (i = 0; i < num_to_be_freed; i++) {
+ zone_free(zone, to_be_freed[i]);
+ to_be_freed[i] = NULL;
+ }
+}
+
+static size_t zone_pressure_relief(malloc_zone_t* zone, size_t goal) {
+ return 0;
+}
+
+static size_t zone_good_size(malloc_zone_t* zone, size_t size) {
+ return malloc_good_size_impl(size);
+}
+
+static kern_return_t zone_enumerator(task_t task, void* data,
+ unsigned type_mask,
+ vm_address_t zone_address,
+ memory_reader_t reader,
+ vm_range_recorder_t recorder) {
+ return KERN_SUCCESS;
+}
+
+static boolean_t zone_check(malloc_zone_t* zone) { return true; }
+
+static void zone_print(malloc_zone_t* zone, boolean_t verbose) {}
+
+static void zone_log(malloc_zone_t* zone, void* address) {}
+
+extern void _malloc_prefork(void);
+extern void _malloc_postfork_child(void);
+
+static void zone_force_lock(malloc_zone_t* zone) {
+ // /!\ This calls into mozjemalloc. It works because we're linked in the
+ // same library.
+ _malloc_prefork();
+}
+
+static void zone_force_unlock(malloc_zone_t* zone) {
+ // /!\ This calls into mozjemalloc. It works because we're linked in the
+ // same library.
+ _malloc_postfork_child();
+}
+
+static void zone_statistics(malloc_zone_t* zone, malloc_statistics_t* stats) {
+ // We make no effort to actually fill the values
+ stats->blocks_in_use = 0;
+ stats->size_in_use = 0;
+ stats->max_size_in_use = 0;
+ stats->size_allocated = 0;
+}
+
+static boolean_t zone_locked(malloc_zone_t* zone) {
+ // Pretend no lock is being held
+ return false;
+}
+
+static void zone_reinit_lock(malloc_zone_t* zone) {
+ // As of OSX 10.12, this function is only used when force_unlock would
+ // be used if the zone version were < 9. So just use force_unlock.
+ zone_force_unlock(zone);
+}
+
+static malloc_zone_t zone;
+static struct malloc_introspection_t zone_introspect;
+
+static malloc_zone_t* get_default_zone() {
+ malloc_zone_t** zones = NULL;
+ unsigned int num_zones = 0;
+
+ // On OSX 10.12, malloc_default_zone returns a special zone that is not
+ // present in the list of registered zones. That zone uses a "lite zone"
+ // if one is present (apparently enabled when malloc stack logging is
+ // enabled), or the first registered zone otherwise. In practice this
+ // means unless malloc stack logging is enabled, the first registered
+ // zone is the default.
+ // So get the list of zones to get the first one, instead of relying on
+ // malloc_default_zone.
+ if (KERN_SUCCESS !=
+ malloc_get_all_zones(0, NULL, (vm_address_t**)&zones, &num_zones)) {
+ // Reset the value in case the failure happened after it was set.
+ num_zones = 0;
+ }
+ if (num_zones) {
+ return zones[0];
+ }
+ return malloc_default_zone();
+}
+
+__attribute__((constructor)) static void register_zone(void) {
+ malloc_zone_t* default_zone = get_default_zone();
+
+ zone.size = zone_size;
+ zone.malloc = zone_malloc;
+ zone.calloc = zone_calloc;
+ zone.valloc = zone_valloc;
+ zone.free = zone_free;
+ zone.realloc = zone_realloc;
+ zone.destroy = zone_destroy;
+#ifdef MOZ_REPLACE_MALLOC
+ zone.zone_name = "replace_malloc_zone";
+#else
+ zone.zone_name = "jemalloc_zone";
+#endif
+ zone.batch_malloc = zone_batch_malloc;
+ zone.batch_free = zone_batch_free;
+ zone.introspect = &zone_introspect;
+ zone.version = 9;
+ zone.memalign = zone_memalign;
+ zone.free_definite_size = zone_free_definite_size;
+ zone.pressure_relief = zone_pressure_relief;
+ zone_introspect.enumerator = zone_enumerator;
+ zone_introspect.good_size = zone_good_size;
+ zone_introspect.check = zone_check;
+ zone_introspect.print = zone_print;
+ zone_introspect.log = zone_log;
+ zone_introspect.force_lock = zone_force_lock;
+ zone_introspect.force_unlock = zone_force_unlock;
+ zone_introspect.statistics = zone_statistics;
+ zone_introspect.zone_locked = zone_locked;
+ zone_introspect.enable_discharge_checking = NULL;
+ zone_introspect.disable_discharge_checking = NULL;
+ zone_introspect.discharge = NULL;
+#ifdef __BLOCKS__
+ zone_introspect.enumerate_discharged_pointers = NULL;
+#else
+ zone_introspect.enumerate_unavailable_without_blocks = NULL;
+#endif
+ zone_introspect.reinit_lock = zone_reinit_lock;
+
+ // The default purgeable zone is created lazily by OSX's libc. It uses
+ // the default zone when it is created for "small" allocations
+ // (< 15 KiB), but assumes the default zone is a scalable_zone. This
+ // obviously fails when the default zone is the jemalloc zone, so
+ // malloc_default_purgeable_zone is called beforehand so that the
+ // default purgeable zone is created when the default zone is still
+ // a scalable_zone.
+ malloc_zone_t* purgeable_zone = malloc_default_purgeable_zone();
+
+ // There is a problem related to the above with the system nano zone, which
+ // is hard to work around from here, and that is instead worked around by
+ // disabling the nano zone through an environment variable
+ // (MallocNanoZone=0). In Firefox, we do that through
+ // browser/app/macbuild/Contents/Info.plist.in.
+
+ // Register the custom zone. At this point it won't be the default.
+ malloc_zone_register(&zone);
+
+ do {
+ // Unregister and reregister the default zone. On OSX >= 10.6,
+ // unregistering takes the last registered zone and places it at the
+ // location of the specified zone. Unregistering the default zone thus
+ // makes the last registered one the default. On OSX < 10.6,
+ // unregistering shifts all registered zones. The first registered zone
+ // then becomes the default.
+ malloc_zone_unregister(default_zone);
+ malloc_zone_register(default_zone);
+
+ // On OSX 10.6, having the default purgeable zone appear before the default
+ // zone makes some things crash because it thinks it owns the default
+ // zone allocated pointers. We thus unregister/re-register it in order to
+ // ensure it's always after the default zone. On OSX < 10.6, as
+ // unregistering shifts registered zones, this simply removes the purgeable
+ // zone from the list and adds it back at the end, after the default zone.
+ // On OSX >= 10.6, unregistering replaces the purgeable zone with the last
+ // registered zone above, i.e the default zone. Registering it again then
+ // puts it at the end, obviously after the default zone.
+ malloc_zone_unregister(purgeable_zone);
+ malloc_zone_register(purgeable_zone);
+ default_zone = get_default_zone();
+ } while (default_zone != &zone);
+}