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--- libmalloc/libmalloc-317.121.1/src/magazine_large.c
+++ /dev/null
@@ -1,851 +0,0 @@
-/*
- * Copyright (c) 2015 Apple Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-
-#include "internal.h"
-
-void
-large_debug_print(task_t task, unsigned level, vm_address_t zone_address,
- memory_reader_t reader, print_task_printer_t printer)
-{
- szone_t *mapped_szone;
- if (reader(task, zone_address, sizeof(szone_t), (void **)&mapped_szone)) {
- printer("Failed to read szone structure\n");
- return;
- }
-
- unsigned index;
- large_entry_t *range;
- _SIMPLE_STRING b = _simple_salloc();
-
- if (b) {
- large_entry_t *mapped_large_entries;
- if (reader(task, (vm_address_t)mapped_szone->large_entries,
- mapped_szone->num_large_entries * sizeof(large_entry_t),
- (void **)&mapped_large_entries)) {
- printer("Failed to read large entries\n");
- return;
- }
-
- _simple_sprintf(b, "Large allocator active blocks - total %y:\n",
- mapped_szone->num_bytes_in_large_objects);
- for (index = 0, range = mapped_large_entries;
- index < mapped_szone->num_large_entries; index++, range++) {
- if (range->address) {
- _simple_sprintf(b, " Slot %5d: %p, size %y", index,
- (void *)range->address, range->size);
- _simple_sprintf(b, "%s\n",
- (range->did_madvise_reusable ? ", madvised" : ""));
- }
- }
-
-#if CONFIG_LARGE_CACHE
- if (large_cache_enabled) {
- _simple_sprintf(b, "\nLarge allocator death row cache, %d entries\n"
- "\tMax cached size:\t%y\n",
- mapped_szone->large_cache_depth,
- (uint64_t)mapped_szone->large_cache_entry_limit);
- _simple_sprintf(b, "\tCurrent size:\t\t%y\n\tReserve size:\t\t%y\n"
- "\tReserve limit:\t\t%y\n",
- mapped_szone->large_entry_cache_bytes,
- mapped_szone->large_entry_cache_reserve_bytes,
- mapped_szone->large_entry_cache_reserve_limit);
- for (index = 0, range = mapped_szone->large_entry_cache;
- index < mapped_szone->large_cache_depth; index++, range++) {
- _simple_sprintf(b, " Slot %5d: %p, size %y", index,
- (void *)range->address, range->size);
- char *age = "";
- if (index == mapped_szone->large_entry_cache_newest) {
- age = "[newest]";
- } else if (index == mapped_szone->large_entry_cache_oldest) {
- age = "[oldest]";
- }
- _simple_sprintf(b, " %s %s\n", age,
- (range->did_madvise_reusable ? " madvised" : ""));
- }
- _simple_sprintf(b, "\n");
- }
- else
-#endif // CONFIG_LARGE_CACHE
- {
- _simple_sprintf(b, "Large allocator death row cache not configured\n");
- }
- printer("%s\n", _simple_string(b));
- _simple_sfree(b);
- }
-}
-
-#if DEBUG_MALLOC
-static void
-large_debug_print_self(szone_t *szone, boolean_t verbose)
-{
- large_debug_print(mach_task_self(), verbose ? MALLOC_VERBOSE_PRINT_LEVEL : 0,
- (vm_address_t)szone, _malloc_default_reader, malloc_report_simple);
-}
-#endif // DEBUG_MALLOC
-
-/*
- * Scan the hash ring looking for an entry containing a given pointer.
- */
-static large_entry_t *
-large_entry_containing_pointer_no_lock(szone_t *szone, const void *ptr)
-{
- // result only valid with lock held
- unsigned num_large_entries = szone->num_large_entries;
- unsigned hash_index;
- unsigned index;
- large_entry_t *range;
-
- if (!num_large_entries) {
- return NULL;
- }
-
- hash_index = ((uintptr_t)ptr >> vm_page_quanta_shift) % num_large_entries;
- index = hash_index;
-
- do {
- range = szone->large_entries + index;
- if (range->address == (vm_address_t)ptr) {
- return range;
- } else if ((vm_address_t)ptr >= range->address
- && (vm_address_t)ptr < range->address + range->size) {
- return range;
- }
-
- // Since we may be looking for an inner pointer, we might not get an
- // exact match on the address, so we need to scan further and to skip
- // over empty entries. It will usually be faster to scan backwards.
- index = index == 0 ? num_large_entries - 1 : index - 1;
- } while (index != hash_index);
-
- return NULL;
-}
-
-/*
- * Scan the hash ring looking for an entry for the given pointer.
- */
-large_entry_t *
-large_entry_for_pointer_no_lock(szone_t *szone, const void *ptr)
-{
- // result only valid with lock held
- unsigned num_large_entries = szone->num_large_entries;
- unsigned hash_index;
- unsigned index;
- large_entry_t *range;
-
- if (!num_large_entries) {
- return NULL;
- }
-
- hash_index = ((uintptr_t)ptr >> vm_page_quanta_shift) % num_large_entries;
- index = hash_index;
-
- do {
- range = szone->large_entries + index;
- if (range->address == (vm_address_t)ptr) {
- return range;
- }
- if (0 == range->address) {
- return NULL; // end of chain
- }
- index++;
- if (index == num_large_entries) {
- index = 0;
- }
- } while (index != hash_index);
-
- return NULL;
-}
-
-static void
-large_entry_insert_no_lock(szone_t *szone, large_entry_t range)
-{
- unsigned num_large_entries = szone->num_large_entries;
- unsigned hash_index = (((uintptr_t)(range.address)) >> vm_page_quanta_shift) % num_large_entries;
- unsigned index = hash_index;
- large_entry_t *entry;
-
- // assert(szone->num_large_objects_in_use < szone->num_large_entries); /* must be called with room to spare */
-
- do {
- entry = szone->large_entries + index;
- if (0 == entry->address) {
- *entry = range;
- return; // end of chain
- }
- index++;
- if (index == num_large_entries) {
- index = 0;
- }
- } while (index != hash_index);
-
- // assert(0); /* must not fallthrough! */
-}
-
-// FIXME: can't we simply swap the (now empty) entry with the last entry on the collision chain for this hash slot?
-static MALLOC_INLINE void
-large_entries_rehash_after_entry_no_lock(szone_t *szone, large_entry_t *entry)
-{
- unsigned num_large_entries = szone->num_large_entries;
- uintptr_t hash_index = entry - szone->large_entries;
- uintptr_t index = hash_index;
- large_entry_t range;
-
- // assert(entry->address == 0) /* caller must have cleared *entry */
-
- do {
- index++;
- if (index == num_large_entries) {
- index = 0;
- }
- range = szone->large_entries[index];
- if (0 == range.address) {
- return;
- }
- szone->large_entries[index].address = (vm_address_t)0;
- szone->large_entries[index].size = 0;
- szone->large_entries[index].did_madvise_reusable = FALSE;
- large_entry_insert_no_lock(szone, range); // this will reinsert in the
- // proper place
- } while (index != hash_index);
-
- // assert(0); /* since entry->address == 0, must not fallthrough! */
-}
-
-// FIXME: num should probably be a size_t, since you can theoretically allocate
-// more than 2^32-1 large_threshold objects in 64 bit.
-static MALLOC_INLINE large_entry_t *
-large_entries_alloc_no_lock(szone_t *szone, unsigned num)
-{
- size_t size = num * sizeof(large_entry_t);
-
- // Note that we allocate memory (via a system call) under a spin lock
- // That is certainly evil, however it's very rare in the lifetime of a process
- // The alternative would slow down the normal case
- unsigned flags = MALLOC_APPLY_LARGE_ASLR(szone->debug_flags & (DISABLE_ASLR | DISABLE_LARGE_ASLR));
- return mvm_allocate_pages(round_large_page_quanta(size), 0, flags, VM_MEMORY_MALLOC_LARGE);
-}
-
-void
-large_entries_free_no_lock(szone_t *szone, large_entry_t *entries, unsigned num, vm_range_t *range_to_deallocate)
-{
- size_t size = num * sizeof(large_entry_t);
-
- range_to_deallocate->address = (vm_address_t)entries;
- range_to_deallocate->size = round_large_page_quanta(size);
-}
-
-static large_entry_t *
-large_entries_grow_no_lock(szone_t *szone, vm_range_t *range_to_deallocate)
-{
- // sets range_to_deallocate
- unsigned old_num_entries = szone->num_large_entries;
- large_entry_t *old_entries = szone->large_entries;
- // always an odd number for good hashing
- unsigned new_num_entries =
- (old_num_entries) ? old_num_entries * 2 + 1 : (unsigned)((large_vm_page_quanta_size / sizeof(large_entry_t)) - 1);
- large_entry_t *new_entries = large_entries_alloc_no_lock(szone, new_num_entries);
- unsigned index = old_num_entries;
- large_entry_t oldRange;
-
- // if the allocation of new entries failed, bail
- if (new_entries == NULL) {
- return NULL;
- }
-
- szone->num_large_entries = new_num_entries;
- szone->large_entries = new_entries;
-
- /* rehash entries into the new list */
- while (index--) {
- oldRange = old_entries[index];
- if (oldRange.address) {
- large_entry_insert_no_lock(szone, oldRange);
- }
- }
-
- if (old_entries) {
- large_entries_free_no_lock(szone, old_entries, old_num_entries, range_to_deallocate);
- } else {
- range_to_deallocate->address = (vm_address_t)0;
- range_to_deallocate->size = 0;
- }
-
- return new_entries;
-}
-
-// frees the specific entry in the size table
-// returns a range to truly deallocate
-static vm_range_t
-large_entry_free_no_lock(szone_t *szone, large_entry_t *entry)
-{
- vm_range_t range;
-
- MALLOC_TRACE(TRACE_large_free, (uintptr_t)szone, (uintptr_t)entry->address, entry->size, 0);
-
- range.address = entry->address;
- range.size = entry->size;
-
- if (szone->debug_flags & MALLOC_ADD_GUARD_PAGE_FLAGS) {
- mvm_protect((void *)range.address, range.size, PROT_READ | PROT_WRITE, szone->debug_flags);
- range.address -= large_vm_page_quanta_size;
- range.size += 2 * large_vm_page_quanta_size;
- }
-
- entry->address = 0;
- entry->size = 0;
- entry->did_madvise_reusable = FALSE;
- large_entries_rehash_after_entry_no_lock(szone, entry);
-
-#if DEBUG_MALLOC
- if (large_entry_for_pointer_no_lock(szone, (void *)range.address)) {
- large_debug_print_self(szone, 1);
- malloc_report(ASL_LEVEL_ERR, "*** freed entry %p still in use; num_large_entries=%d\n", (void *)range.address, szone->num_large_entries);
- }
-#endif
- return range;
-}
-
-kern_return_t
-large_in_use_enumerator(task_t task,
- void *context,
- unsigned type_mask,
- vm_address_t large_entries_address,
- unsigned num_entries,
- memory_reader_t reader,
- vm_range_recorder_t recorder)
-{
- unsigned index = 0;
- vm_range_t buffer[MAX_RECORDER_BUFFER];
- unsigned count = 0;
- large_entry_t *entries;
- kern_return_t err;
- vm_range_t range;
- large_entry_t entry;
-
- err = reader(task, large_entries_address, sizeof(large_entry_t) * num_entries, (void **)&entries);
- if (err) {
- return err;
- }
-
- index = num_entries;
- if (type_mask & MALLOC_ADMIN_REGION_RANGE_TYPE) {
- range.address = large_entries_address;
- range.size = round_large_page_quanta(num_entries * sizeof(large_entry_t));
- recorder(task, context, MALLOC_ADMIN_REGION_RANGE_TYPE, &range, 1);
- }
- if (type_mask & (MALLOC_PTR_IN_USE_RANGE_TYPE | MALLOC_PTR_REGION_RANGE_TYPE)) {
- while (index--) {
- entry = entries[index];
- if (entry.address) {
- range.address = entry.address;
- range.size = entry.size;
- buffer[count++] = range;
- if (count >= MAX_RECORDER_BUFFER) {
- recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE | MALLOC_PTR_REGION_RANGE_TYPE, buffer, count);
- count = 0;
- }
- }
- }
- }
- if (count) {
- recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE | MALLOC_PTR_REGION_RANGE_TYPE, buffer, count);
- }
- return 0;
-}
-
-void *
-large_malloc(szone_t *szone, size_t num_kernel_pages, unsigned char alignment, boolean_t cleared_requested)
-{
- void *addr;
- vm_range_t range_to_deallocate;
- size_t size;
- large_entry_t large_entry;
-
- MALLOC_TRACE(TRACE_large_malloc, (uintptr_t)szone, num_kernel_pages, alignment, cleared_requested);
-
- if (!num_kernel_pages) {
- num_kernel_pages = 1; // minimal allocation size for this szone
- }
- size = (size_t)num_kernel_pages << large_vm_page_quanta_shift;
- range_to_deallocate.size = 0;
- range_to_deallocate.address = 0;
-
-#if CONFIG_LARGE_CACHE
- if (large_cache_enabled && size <= szone->large_cache_entry_limit) { // Look for a large_entry_t on the death-row cache?
- SZONE_LOCK(szone);
-
- int i, best = -1, idx = szone->large_entry_cache_newest, stop_idx = szone->large_entry_cache_oldest;
- size_t best_size = SIZE_T_MAX;
-
- while (1) { // Scan large_entry_cache for best fit, starting with most recent entry
- size_t this_size = szone->large_entry_cache[idx].size;
- addr = (void *)szone->large_entry_cache[idx].address;
-
- if (0 == alignment || 0 == (((uintptr_t)addr) & (((uintptr_t)1 << alignment) - 1))) {
- if (size == this_size) { // size match!
- best = idx;
- best_size = this_size;
- break;
- }
-
- if (size <= this_size && this_size < best_size) { // improved fit?
- best = idx;
- best_size = this_size;
- }
- }
-
- if (idx == stop_idx) { // exhausted live ring?
- break;
- }
-
- if (idx) {
- idx--; // bump idx down
- } else {
- idx = szone->large_cache_depth - 1; // wrap idx
- }
- }
-
- if (best > -1 && (best_size - size) < size) { // limit fragmentation to 50%
- addr = (void *)szone->large_entry_cache[best].address;
- boolean_t was_madvised_reusable = szone->large_entry_cache[best].did_madvise_reusable;
-
- // Compact live ring to fill entry now vacated at large_entry_cache[best]
- // while preserving time-order
- if (szone->large_entry_cache_oldest < szone->large_entry_cache_newest) {
- // Ring hasn't wrapped. Fill in from right.
- for (i = best; i < szone->large_entry_cache_newest; ++i) {
- szone->large_entry_cache[i] = szone->large_entry_cache[i + 1];
- }
-
- szone->large_entry_cache_newest--; // Pull in right endpoint.
-
- } else if (szone->large_entry_cache_newest < szone->large_entry_cache_oldest) {
- // Ring has wrapped. Arrange to fill in from the contiguous side.
- if (best <= szone->large_entry_cache_newest) {
- // Fill from right.
- for (i = best; i < szone->large_entry_cache_newest; ++i) {
- szone->large_entry_cache[i] = szone->large_entry_cache[i + 1];
- }
-
- if (0 < szone->large_entry_cache_newest) {
- szone->large_entry_cache_newest--;
- } else {
- szone->large_entry_cache_newest = szone->large_cache_depth - 1;
- }
- } else {
- // Fill from left.
- for (i = best; i > szone->large_entry_cache_oldest; --i) {
- szone->large_entry_cache[i] = szone->large_entry_cache[i - 1];
- }
-
- if (szone->large_entry_cache_oldest < szone->large_cache_depth - 1) {
- szone->large_entry_cache_oldest++;
- } else {
- szone->large_entry_cache_oldest = 0;
- }
- }
-
- } else {
- // By trichotomy, large_entry_cache_newest == large_entry_cache_oldest.
- // That implies best == large_entry_cache_newest == large_entry_cache_oldest
- // and the ring is now empty.
- szone->large_entry_cache[best].address = 0;
- szone->large_entry_cache[best].size = 0;
- szone->large_entry_cache[best].did_madvise_reusable = FALSE;
- }
-
- if ((szone->num_large_objects_in_use + 1) * 4 > szone->num_large_entries) {
- // density of hash table too high; grow table
- // we do that under lock to avoid a race
- large_entry_t *entries = large_entries_grow_no_lock(szone, &range_to_deallocate);
- if (entries == NULL) {
- SZONE_UNLOCK(szone);
- return NULL;
- }
- }
-
- large_entry.address = (vm_address_t)addr;
- large_entry.size = best_size;
- large_entry.did_madvise_reusable = FALSE;
- large_entry_insert_no_lock(szone, large_entry);
-
- szone->num_large_objects_in_use++;
- szone->num_bytes_in_large_objects += best_size;
- if (!was_madvised_reusable) {
- szone->large_entry_cache_reserve_bytes -= best_size;
- }
-
- szone->large_entry_cache_bytes -= best_size;
-
- if (szone->flotsam_enabled && szone->large_entry_cache_bytes < SZONE_FLOTSAM_THRESHOLD_LOW) {
- szone->flotsam_enabled = FALSE;
- }
-
- SZONE_UNLOCK(szone);
-
- if (range_to_deallocate.size) {
- // we deallocate outside the lock
- mvm_deallocate_pages((void *)range_to_deallocate.address, range_to_deallocate.size, 0);
- }
-
- if (cleared_requested) {
- memset(addr, 0, size);
- }
-
- return addr;
- } else {
- SZONE_UNLOCK(szone);
- }
- }
-
- range_to_deallocate.size = 0;
- range_to_deallocate.address = 0;
-#endif /* CONFIG_LARGE_CACHE */
-
- // NOTE: we do not use MALLOC_FIX_GUARD_PAGE_FLAGS(szone->debug_flags) here
- // because we want to always add either no guard page or both guard pages.
- addr = mvm_allocate_pages(size, alignment, MALLOC_APPLY_LARGE_ASLR(szone->debug_flags), VM_MEMORY_MALLOC_LARGE);
- if (addr == NULL) {
- return NULL;
- }
-
- SZONE_LOCK(szone);
- if ((szone->num_large_objects_in_use + 1) * 4 > szone->num_large_entries) {
- // density of hash table too high; grow table
- // we do that under lock to avoid a race
- large_entry_t *entries = large_entries_grow_no_lock(szone, &range_to_deallocate);
- if (entries == NULL) {
- SZONE_UNLOCK(szone);
- return NULL;
- }
- }
-
- large_entry.address = (vm_address_t)addr;
- large_entry.size = size;
- large_entry.did_madvise_reusable = FALSE;
- large_entry_insert_no_lock(szone, large_entry);
-
- szone->num_large_objects_in_use++;
- szone->num_bytes_in_large_objects += size;
- SZONE_UNLOCK(szone);
-
- if (range_to_deallocate.size) {
- // we deallocate outside the lock
- mvm_deallocate_pages((void *)range_to_deallocate.address, range_to_deallocate.size, 0);
- }
- return addr;
-}
-
-void
-free_large(szone_t *szone, void *ptr)
-{
- // We have established ptr is page-aligned and neither tiny nor small
- large_entry_t *entry;
- vm_range_t vm_range_to_deallocate;
-
- SZONE_LOCK(szone);
- entry = large_entry_for_pointer_no_lock(szone, ptr);
- if (entry) {
-#if CONFIG_LARGE_CACHE
- if (large_cache_enabled &&
- entry->size <= szone->large_cache_entry_limit &&
- -1 != madvise((void *)(entry->address), entry->size,
- MADV_CAN_REUSE)) { // Put the large_entry_t on the death-row cache?
- int idx = szone->large_entry_cache_newest, stop_idx = szone->large_entry_cache_oldest;
- large_entry_t this_entry = *entry; // Make a local copy, "entry" is volatile when lock is let go.
- boolean_t reusable = TRUE;
- boolean_t should_madvise =
- szone->large_entry_cache_reserve_bytes + this_entry.size > szone->large_entry_cache_reserve_limit;
-
- // Already freed?
- // [Note that repeated entries in death-row risk vending the same entry subsequently
- // to two different malloc() calls. By checking here the (illegal) double free
- // is accommodated, matching the behavior of the previous implementation.]
- while (1) { // Scan large_entry_cache starting with most recent entry
- if (szone->large_entry_cache[idx].address == entry->address) {
- malloc_zone_error(szone->debug_flags, true, "pointer %p being freed already on death-row\n", ptr);
- SZONE_UNLOCK(szone);
- return;
- }
-
- if (idx == stop_idx) { // exhausted live ring?
- break;
- }
-
- if (idx) {
- idx--; // bump idx down
- } else {
- idx = szone->large_cache_depth - 1; // wrap idx
- }
- }
-
- SZONE_UNLOCK(szone);
-
- if (szone->debug_flags & MALLOC_PURGEABLE) { // Are we a purgable zone?
- int state = VM_PURGABLE_NONVOLATILE; // restore to default condition
-
- if (KERN_SUCCESS != vm_purgable_control(mach_task_self(), this_entry.address, VM_PURGABLE_SET_STATE, &state)) {
- malloc_report(ASL_LEVEL_ERR, "*** can't vm_purgable_control(..., VM_PURGABLE_SET_STATE) for large freed block at %p\n",
- (void *)this_entry.address);
- reusable = FALSE;
- }
- }
-
- if (szone->large_legacy_reset_mprotect) { // Linked for Leopard?
- // Accomodate Leopard apps that (illegally) mprotect() their own guard pages on large malloc'd allocations
- int err = mprotect((void *)(this_entry.address), this_entry.size, PROT_READ | PROT_WRITE);
- if (err) {
- malloc_report(ASL_LEVEL_ERR, "*** can't reset protection for large freed block at %p\n", (void *)this_entry.address);
- reusable = FALSE;
- }
- }
-
- // madvise(..., MADV_REUSABLE) death-row arrivals if hoarding would exceed large_entry_cache_reserve_limit
- if (should_madvise) {
- // Issue madvise to avoid paging out the dirtied free()'d pages in "entry"
- MAGMALLOC_MADVFREEREGION((void *)szone, (void *)0, (void *)(this_entry.address), (int)this_entry.size); // DTrace USDT Probe
-
- // Ok to do this madvise on embedded because we won't call MADV_FREE_REUSABLE on a large
- // cache block twice without MADV_FREE_REUSE in between.
-
- if (-1 == madvise((void *)(this_entry.address), this_entry.size, MADV_FREE_REUSABLE)) {
- /* -1 return: VM map entry change makes this unfit for reuse. */
-#if DEBUG_MADVISE
- malloc_zone_error(szone->debug_flags, false,
- "free_large madvise(..., MADV_FREE_REUSABLE) failed for %p, length=%d\n",
- (void *)this_entry.address, this_entry.size);
-#endif
- reusable = FALSE;
- }
- }
-
- SZONE_LOCK(szone);
-
- // Re-acquire "entry" after interval just above where we let go the lock.
- entry = large_entry_for_pointer_no_lock(szone, ptr);
- if (NULL == entry) {
- malloc_zone_error(szone->debug_flags, true, "entry for pointer %p being freed from death-row vanished\n", ptr);
- SZONE_UNLOCK(szone);
- return;
- }
-
- // Add "entry" to death-row ring
- if (reusable) {
- int idx = szone->large_entry_cache_newest; // Most recently occupied
- vm_address_t addr;
- size_t adjsize;
-
- if (szone->large_entry_cache_newest == szone->large_entry_cache_oldest &&
- 0 == szone->large_entry_cache[idx].address) {
- // Ring is empty, idx is good as it stands
- addr = 0;
- adjsize = 0;
- } else {
- // Extend the queue to the "right" by bumping up large_entry_cache_newest
- if (idx == szone->large_cache_depth - 1) {
- idx = 0; // Wrap index
- } else {
- idx++; // Bump index
- }
- if (idx == szone->large_entry_cache_oldest) { // Fully occupied
- // Drop this entry from the cache and deallocate the VM
- addr = szone->large_entry_cache[idx].address;
- adjsize = szone->large_entry_cache[idx].size;
- szone->large_entry_cache_bytes -= adjsize;
- if (!szone->large_entry_cache[idx].did_madvise_reusable) {
- szone->large_entry_cache_reserve_bytes -= adjsize;
- }
- } else {
- // Using an unoccupied cache slot
- addr = 0;
- adjsize = 0;
- }
- }
-
- if ((szone->debug_flags & MALLOC_DO_SCRIBBLE)) {
- memset((void *)(entry->address), should_madvise ? SCRUBBLE_BYTE : SCRABBLE_BYTE, entry->size);
- }
-
- entry->did_madvise_reusable = should_madvise; // Was madvise()'d above?
- if (!should_madvise) { // Entered on death-row without madvise() => up the hoard total
- szone->large_entry_cache_reserve_bytes += entry->size;
- }
-
- szone->large_entry_cache_bytes += entry->size;
-
- if (!szone->flotsam_enabled && szone->large_entry_cache_bytes > SZONE_FLOTSAM_THRESHOLD_HIGH) {
- szone->flotsam_enabled = TRUE;
- }
-
- szone->large_entry_cache[idx] = *entry;
- szone->large_entry_cache_newest = idx;
-
- szone->num_large_objects_in_use--;
- szone->num_bytes_in_large_objects -= entry->size;
-
- (void)large_entry_free_no_lock(szone, entry);
-
- if (0 == addr) {
- SZONE_UNLOCK(szone);
- return;
- }
-
- // Fall through to drop large_entry_cache_oldest from the cache,
- // and then deallocate its pages.
-
- // Trim the queue on the "left" by bumping up large_entry_cache_oldest
- if (szone->large_entry_cache_oldest == szone->large_cache_depth - 1) {
- szone->large_entry_cache_oldest = 0;
- } else {
- szone->large_entry_cache_oldest++;
- }
-
- // we deallocate_pages, including guard pages, outside the lock
- SZONE_UNLOCK(szone);
- mvm_deallocate_pages((void *)addr, (size_t)adjsize, 0);
- return;
- } else {
- /* fall through to discard an allocation that is not reusable */
- }
- }
-#endif /* CONFIG_LARGE_CACHE */
-
- szone->num_large_objects_in_use--;
- szone->num_bytes_in_large_objects -= entry->size;
-
- vm_range_to_deallocate = large_entry_free_no_lock(szone, entry);
- } else {
-#if DEBUG_MALLOC
- large_debug_print_self(szone, 1);
-#endif
- malloc_zone_error(szone->debug_flags, true, "pointer %p being freed was not allocated\n", ptr);
- SZONE_UNLOCK(szone);
- return;
- }
- SZONE_UNLOCK(szone); // we release the lock asap
- CHECK(szone, __PRETTY_FUNCTION__);
-
- // we deallocate_pages, including guard pages, outside the lock
- if (vm_range_to_deallocate.address) {
-#if DEBUG_MALLOC
- // FIXME: large_entry_for_pointer_no_lock() needs the lock held ...
- if (large_entry_for_pointer_no_lock(szone, (void *)vm_range_to_deallocate.address)) {
- large_debug_print_self(szone, 1);
- malloc_report(ASL_LEVEL_ERR, "*** invariant broken: %p still in use num_large_entries=%d\n",
- (void *)vm_range_to_deallocate.address, szone->num_large_entries);
- }
-#endif
- mvm_deallocate_pages((void *)vm_range_to_deallocate.address, (size_t)vm_range_to_deallocate.size, 0);
- }
-}
-
-void *
-large_try_shrink_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_good_size)
-{
- size_t shrinkage = old_size - new_good_size;
-
- if (shrinkage) {
- SZONE_LOCK(szone);
- /* contract existing large entry */
- large_entry_t *large_entry = large_entry_for_pointer_no_lock(szone, ptr);
- if (!large_entry) {
- malloc_zone_error(szone->debug_flags, true, "large entry %p reallocated is not properly in table\n", ptr);
- SZONE_UNLOCK(szone);
- return ptr;
- }
-
- large_entry->address = (vm_address_t)ptr;
- large_entry->size = new_good_size;
- szone->num_bytes_in_large_objects -= shrinkage;
- boolean_t guarded = szone->debug_flags & MALLOC_ADD_GUARD_PAGE_FLAGS;
- SZONE_UNLOCK(szone); // we release the lock asap
-
- if (guarded) {
- // Keep the page above the new end of the allocation as the
- // postlude guard page.
- kern_return_t err;
- err = mprotect((void *)((uintptr_t)ptr + new_good_size), large_vm_page_quanta_size, 0);
- if (err) {
- malloc_report(ASL_LEVEL_ERR, "*** can't mvm_protect(0x0) region for new postlude guard page at %p\n",
- ptr + new_good_size);
- }
- new_good_size += large_vm_page_quanta_size;
- shrinkage -= large_vm_page_quanta_size;
- }
-
- mvm_deallocate_pages((void *)((uintptr_t)ptr + new_good_size), shrinkage, 0);
- }
- return ptr;
-}
-
-int
-large_try_realloc_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size)
-{
- vm_address_t addr = (vm_address_t)ptr + old_size;
- large_entry_t *large_entry;
- kern_return_t err;
-
- SZONE_LOCK(szone);
- large_entry = large_entry_for_pointer_no_lock(szone, (void *)addr);
- SZONE_UNLOCK(szone);
-
- if (large_entry) { // check if "addr = ptr + old_size" is already spoken for
- return 0; // large pointer already exists in table - extension is not going to work
- }
-
- new_size = round_large_page_quanta(new_size);
- /*
- * Ask for allocation at a specific address, and mark as realloc
- * to request coalescing with previous realloc'ed extensions.
- */
- err = vm_allocate(mach_task_self(), &addr, new_size - old_size, VM_MAKE_TAG(VM_MEMORY_REALLOC));
- if (err != KERN_SUCCESS) {
- return 0;
- }
-
- SZONE_LOCK(szone);
- /* extend existing large entry */
- large_entry = large_entry_for_pointer_no_lock(szone, ptr);
- if (!large_entry) {
- malloc_zone_error(szone->debug_flags, true, "large entry %p reallocated is not properly in table\n", ptr);
- SZONE_UNLOCK(szone);
- return 0; // Bail, leaking "addr"
- }
-
- large_entry->address = (vm_address_t)ptr;
- large_entry->size = new_size;
- szone->num_bytes_in_large_objects += new_size - old_size;
- SZONE_UNLOCK(szone); // we release the lock asap
-
- return 1;
-}
-
-boolean_t
-large_claimed_address(szone_t *szone, void *ptr)
-{
- SZONE_LOCK(szone);
- boolean_t result = large_entry_containing_pointer_no_lock(szone,
- (void *)trunc_page((uintptr_t)ptr)) != NULL;
- SZONE_UNLOCK(szone);
- return result;
-}