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--- libmalloc/libmalloc-374.60.3/src/magazine_rack.c
+++ /dev/null
@@ -1,224 +0,0 @@
-/*
- * Copyright (c) 2016 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
-rack_init(rack_t *rack, rack_type_t type, uint32_t num_magazines, uint32_t debug_flags)
-{
- rack->type = type;
- rack->rg[0].nextgen = &rack->rg[1];
- rack->rg[1].nextgen = &rack->rg[0];
- rack->region_generation = &rack->rg[0];
-
- rack->region_generation->hashed_regions = rack->initial_regions;
- rack->region_generation->num_regions_allocated = INITIAL_NUM_REGIONS;
- rack->region_generation->num_regions_allocated_shift = INITIAL_NUM_REGIONS_SHIFT;
-
- memset(rack->initial_regions, '\0', sizeof(region_t) * INITIAL_NUM_REGIONS);
-
- rack->cookie = (uintptr_t)malloc_entropy[0];
-
- if (type == RACK_TYPE_SMALL) {
- // Flip the cookie for SMALL regions so that tiny and small free list
- // entries will trap when used if used in opposing region types.
- rack->cookie = ~rack->cookie;
- }
-
- rack->debug_flags = debug_flags;
- rack->num_magazines = num_magazines;
- rack->num_regions = 0;
- rack->num_regions_dealloc = 0;
- rack->magazines = NULL;
-
- if (num_magazines > 0) {
- // num_magazines + 1, the [-1] index will become the depot magazine
- size_t magsize = round_page_quanta(sizeof(magazine_t) * (num_magazines + 1));
- magazine_t *magazines = mvm_allocate_pages(magsize, 0,
- MALLOC_ADD_GUARD_PAGE_FLAGS|DISABLE_ASLR, VM_MEMORY_MALLOC);
- if (!magazines) {
- MALLOC_REPORT_FATAL_ERROR(0, "unable to allocate magazine array");
- }
-
- rack->magazines = &magazines[1];
- rack->num_magazines_mask_shift = 0;
-
- // The magazines are indexed in [0 .. (num_magazines - 1)]
- // Find the smallest power of 2 that exceeds (num_magazines - 1)
- int i = 1;
- while (i <= (num_magazines - 1)) {
- rack->num_magazines_mask_shift++;
- i <<= 1;
- }
-
- // Reduce i by 1 to obtain a mask covering [0 .. (num_tiny_magazines - 1)]
- rack->num_magazines_mask = i - 1;
- rack->last_madvise = 0;
-
- _malloc_lock_init(&rack->region_lock);
- _malloc_lock_init(&rack->magazines[DEPOT_MAGAZINE_INDEX].magazine_lock);
-
- for (int i=0; i < rack->num_magazines; i++) {
- _malloc_lock_init(&rack->magazines[i].magazine_lock);
- }
- }
-}
-
-void
-rack_destroy_regions(rack_t *rack, size_t region_size)
-{
- /* destroy regions attached to this rack */
- for (int i=0; i < rack->region_generation->num_regions_allocated; i++) {
- if ((rack->region_generation->hashed_regions[i] != HASHRING_OPEN_ENTRY) &&
- (rack->region_generation->hashed_regions[i] != HASHRING_REGION_DEALLOCATED))
- {
- mvm_deallocate_pages(rack->region_generation->hashed_regions[i], region_size, MALLOC_FIX_GUARD_PAGE_FLAGS(rack->debug_flags));
- rack->region_generation->hashed_regions[i] = HASHRING_REGION_DEALLOCATED;
- }
- }
-}
-
-void
-rack_destroy(rack_t *rack)
-{
- /* if the rack has additional regions, then deallocate them */
- if (rack->region_generation->hashed_regions != rack->initial_regions) {
- size_t size = round_page_quanta(rack->region_generation->num_regions_allocated * sizeof(region_t));
- mvm_deallocate_pages(rack->region_generation->hashed_regions, size, 0);
- }
-
- if (rack->num_magazines > 0) {
- size_t size = round_page_quanta(sizeof(magazine_t) * (rack->num_magazines + 1));
- mvm_deallocate_pages(&rack->magazines[-1], size, MALLOC_ADD_GUARD_PAGE_FLAGS);
- rack->magazines = NULL;
- }
-}
-
-void
-rack_region_insert(rack_t *rack, region_t region)
-{
- // Here find the only place in rackland that (infrequently) takes the tiny_regions_lock.
- // Only one thread at a time should be permitted to assess the density of the hash
- // ring and adjust if needed.
- // Only one thread at a time should be permitted to insert its new region on
- // the hash ring.
- // It is safe for all other threads to read the hash ring (hashed_regions) and
- // the associated sizes (num_regions_allocated and num_tiny_regions).
-
- _malloc_lock_lock(&rack->region_lock);
-
- // Check to see if the hash ring of tiny regions needs to grow. Try to
- // avoid the hash ring becoming too dense.
- if (rack->region_generation->num_regions_allocated < (2 * rack->num_regions)) {
- region_t *new_regions;
- size_t new_size;
- size_t new_shift = rack->region_generation->num_regions_allocated_shift; // In/Out parameter
- new_regions = hash_regions_grow_no_lock(rack->region_generation->hashed_regions,
- rack->region_generation->num_regions_allocated, &new_shift, &new_size);
- // Do not deallocate the current hashed_regions allocation since someone may
- // be iterating it. Instead, just leak it.
-
- // Prepare to advance to the "next generation" of the hash ring.
- rack->region_generation->nextgen->hashed_regions = new_regions;
- rack->region_generation->nextgen->num_regions_allocated = new_size;
- rack->region_generation->nextgen->num_regions_allocated_shift = new_shift;
-
- // Ensure everyone sees the advance.
- OSMemoryBarrier();
-
- // Throw the switch to atomically advance to the next generation.
- rack->region_generation = rack->region_generation->nextgen;
- }
-
- // Insert the new region into the hash ring, and update malloc statistics
- hash_region_insert_no_lock(rack->region_generation->hashed_regions,
- rack->region_generation->num_regions_allocated,
- rack->region_generation->num_regions_allocated_shift,
- region);
-
- rack->num_regions++;
- _malloc_lock_unlock(&rack->region_lock);
-}
-
-bool
-rack_region_remove(rack_t *rack, region_t region, region_trailer_t *trailer)
-{
- bool rv = true;
-
- rack_region_lock(rack);
- rgnhdl_t pSlot = hash_lookup_region_no_lock(
- rack->region_generation->hashed_regions,
- rack->region_generation->num_regions_allocated,
- rack->region_generation->num_regions_allocated_shift,
- region);
-
- if ((trailer->dispose_flags & RACK_DISPOSE_DELAY) != 0) {
- // Still remove this region from the hash table but don't allow the
- // current caller to deallocate the region until the pressure thread is
- // done with it.
- trailer->dispose_flags |= RACK_DISPOSE_NEEDED;
- rv = false;
- }
-
- if (NULL == pSlot) {
- malloc_zone_error(rack->debug_flags, true,
- "tiny_free_try_depot_unmap_no_lock hash lookup failed: %p\n",
- region);
- rv = false;
- } else {
- // Invalidate the hash table entry for this region with
- // HASHRING_REGION_DEALLOCATED. Using HASHRING_REGION_DEALLOCATED
- // preserves the collision chain, using HASHRING_OPEN_ENTRY (0) would not.
- *pSlot = HASHRING_REGION_DEALLOCATED;
-
- // Atomically increment num_regions_dealloc
-#ifdef __LP64__
- OSAtomicIncrement64((int64_t *)&rack->num_regions_dealloc);
-#else
- OSAtomicIncrement32((int32_t *)&rack->num_regions_dealloc);
-#endif
- }
-
- rack_region_unlock(rack);
- return rv;
-}
-
-bool
-rack_region_maybe_dispose(rack_t *rack, region_t region, size_t region_size,
- region_trailer_t *trailer)
-{
- bool rv = false;
- rack_region_lock(rack);
-
- if ((trailer->dispose_flags & RACK_DISPOSE_NEEDED) != 0) {
- // We tried to dispose of this region while the pressure thread was
- // using it, so now that it's finished we can deallocate it now.
- mvm_deallocate_pages((void *)region, region_size,
- MALLOC_FIX_GUARD_PAGE_FLAGS(rack->debug_flags));
- rv = true;
- } else {
- trailer->dispose_flags &= ~RACK_DISPOSE_DELAY;
- }
- rack_region_unlock(rack);
- return rv;
-}