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+++ Libc/Libc-498/gen/scalable_malloc.c
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+/*
+ * Copyright (c) 1999, 2006 Apple Computer, 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@
+ */
+
+/* Author: Bertrand Serlet, August 1999 */
+
+#include "scalable_malloc.h"
+#include "malloc_printf.h"
+#include "_simple.h"
+
+#include <pthread_internals.h>
+
+#include <unistd.h>
+#include <libc.h>
+#include <mach/vm_statistics.h>
+#include <mach/mach_init.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+
+/********************* DEFINITIONS ************************/
+
+#define DEBUG_MALLOC 0 // set to one to debug malloc itself
+
+#define DEBUG_CLIENT 0 // set to one to help debug a nasty memory smasher
+
+#if DEBUG_MALLOC
+#warning DEBUG_MALLOC ENABLED
+# define INLINE
+# define ALWAYSINLINE
+# define CHECK_LOCKED(szone, fun) \
+do { \
+ if (__is_threaded && TRY_LOCK(szone->lock)) { \
+ malloc_printf("*** lock was not set %p in %s\n", szone->lock, fun); \
+ } \
+} while (0)
+#else
+# define INLINE __inline__
+# define ALWAYSINLINE __attribute__((always_inline))
+# define CHECK_LOCKED(szone, fun) {}
+#endif
+
+/*
+ * Access to global variables is slow, so optimise our handling of vm_page_size
+ * and vm_page_shift.
+ */
+#define _vm_page_size vm_page_size /* to get to the originals */
+#define _vm_page_shift vm_page_shift
+#define vm_page_size 4096 /* our normal working sizes */
+#define vm_page_shift 12
+
+typedef unsigned short msize_t; // a size in multiples of SHIFT_SMALL_QUANTUM or SHIFT_TINY_QUANTUM
+
+typedef union {
+ void *p;
+ uintptr_t u;
+} ptr_union;
+
+typedef struct {
+ ptr_union previous;
+ ptr_union next;
+} free_list_t;
+
+typedef struct {
+ uintptr_t address_and_num_pages;
+ // this type represents both an address and a number of pages
+ // the low bits are the number of pages; the high bits are the address
+ // note that the exact number of bits used for depends on the page size
+ // also, this cannot represent pointers larger than 1 << (vm_page_shift * 2)
+} compact_range_t;
+
+typedef unsigned char grain_t;
+
+#define CHECK_REGIONS (1 << 31)
+
+#define MAX_RECORDER_BUFFER 256
+
+/********************* DEFINITIONS for tiny ************************/
+
+/*
+ * Memory in the Tiny range is allocated from regions (heaps) pointed to by the szone's tiny_regions
+ * pointer.
+ *
+ * Each region is laid out as a heap, followed by a header block, all within
+ * a 1MB (2^20) block. This means there are 64520 16-byte blocks and the header is
+ * 16138 bytes, making the total 1048458 bytes, leaving 118 bytes unused.
+ * The header block is arranged:
+ *
+ * 0xfc080
+ * header bits
+ * 0xfe001
+ * 0xffffffff pad word
+ * 0xfe005
+ * in-use bits
+ * 0xfff86
+ * pad word (not written)
+ * 0xfff8a-0xfffff
+ * unused
+ *
+ * Each bitfield comprises NUM_TINY_BLOCKS bits, and refers to the corresponding TINY_QUANTUM block
+ * within the heap.
+ *
+ * The bitfields are used to encode the state of memory within the heap. The header bit indicates
+ * that the corresponding quantum is the first quantum in a block (either in use or free). The
+ * in-use bit is set for the header if the block has been handed out (allocated). If the header
+ * bit is not set, the in-use bit is invalid.
+ *
+ * The szone maintains an array of 32 freelists, each of which is used to hold
+ * free objects of the corresponding quantum size.
+ *
+ * A free block is laid out depending on its size, in order to fit all free
+ * blocks in 16 bytes, on both 32 and 64 bit platforms. One quantum blocks do
+ * not store their size in the block, instead relying on the header information
+ * to determine their size. Blocks of two or more quanta have room to store
+ * their size in the block, and store it both after the 'next' pointer, and in
+ * the last 2 bytes of the block.
+ *
+ * 1-quantum block
+ * Offset (32-bit mode) (64-bit mode)
+ * 0x0 0x0 : previous
+ * 0x4 0x08 : next
+ * end end
+ *
+ * >1-quantum block
+ * Offset (32-bit mode) (64-bit mode)
+ * 0x0 0x0 : previous
+ * 0x4 0x08 : next
+ * 0x8 0x10 : size (in quantum counts)
+ * end - 2 end - 2 : size (in quantum counts)
+ * end end
+ *
+ * All fields are pointer-sized, except for the size which is an unsigned short.
+ *
+ */
+
+#define SHIFT_TINY_QUANTUM 4 // Required for AltiVec
+#define TINY_QUANTUM (1 << SHIFT_TINY_QUANTUM)
+
+#define FOLLOWING_TINY_PTR(ptr,msize) (((unsigned char *)(ptr)) + ((msize) << SHIFT_TINY_QUANTUM))
+
+#define NUM_TINY_SLOTS 32 // number of slots for free-lists
+
+#define NUM_TINY_BLOCKS 64520
+#define SHIFT_TINY_CEIL_BLOCKS 16 // ceil(log2(NUM_TINY_BLOCKS))
+#define NUM_TINY_CEIL_BLOCKS (1 << SHIFT_TINY_CEIL_BLOCKS)
+#define TINY_BLOCKS_ALIGN (SHIFT_TINY_CEIL_BLOCKS + SHIFT_TINY_QUANTUM)
+
+/*
+ * Enough room for the data, followed by the bit arrays (2-bits per block) plus 2 words of padding
+ * as our bitmap operators overflow, plus rounding to the nearest page.
+ */
+#define TINY_HEADER_SIZE ((NUM_TINY_BLOCKS >> 2) + 8)
+#define TINY_REGION_SIZE ((NUM_TINY_BLOCKS * TINY_QUANTUM + TINY_HEADER_SIZE + vm_page_size - 1) & ~ (vm_page_size - 1))
+
+/*
+ * Beginning and end pointers for a region's heap.
+ */
+#define TINY_REGION_ADDRESS(region) ((void *)(region))
+#define TINY_REGION_END(region) (TINY_REGION_ADDRESS(region) + (NUM_TINY_BLOCKS * TINY_QUANTUM))
+
+/*
+ * Locate the heap base for a pointer known to be within a tiny region.
+ */
+#define TINY_REGION_FOR_PTR(_p) ((void *)((uintptr_t)(_p) & ~((1 << TINY_BLOCKS_ALIGN) - 1)))
+
+/*
+ * Convert between byte and msize units.
+ */
+#define TINY_BYTES_FOR_MSIZE(_m) ((_m) << SHIFT_TINY_QUANTUM)
+#define TINY_MSIZE_FOR_BYTES(_b) ((_b) >> SHIFT_TINY_QUANTUM)
+
+#ifdef __LP64__
+# define TINY_FREE_SIZE(ptr) (((msize_t *)(ptr))[8])
+#else
+# define TINY_FREE_SIZE(ptr) (((msize_t *)(ptr))[4])
+#endif
+#define TINY_PREVIOUS_MSIZE(ptr) ((msize_t *)(ptr))[-1]
+
+/*
+ * Locate the block header for a pointer known to be within a tiny region.
+ */
+#define TINY_HEADER_START (NUM_TINY_BLOCKS * TINY_QUANTUM)
+#define TINY_BLOCK_HEADER_FOR_PTR(_p) ((void *)((uintptr_t)TINY_REGION_FOR_PTR(_p) + TINY_HEADER_START))
+
+/*
+ * Locate the inuse map for a given block header pointer.
+ */
+#define TINY_INUSE_FOR_HEADER(_h) ((void *)((uintptr_t)(_h) + (NUM_TINY_BLOCKS >> 3) + 4))
+
+/*
+ * Compute the bitmap index for a pointer known to be within a tiny region.
+ */
+#define TINY_INDEX_FOR_PTR(_p) (((uintptr_t)(_p) >> SHIFT_TINY_QUANTUM) & (NUM_TINY_CEIL_BLOCKS - 1))
+
+#define TINY_CACHE 1 // This governs a last-free cache of 1 that bypasses the free-list
+
+#if ! TINY_CACHE
+#warning TINY_CACHE turned off
+#endif
+
+/********************* DEFINITIONS for small ************************/
+
+/*
+ * Memory in the Small range is allocated from regions (heaps) pointed to by the szone's small_regions
+ * pointer.
+ *
+ * Each region is laid out as a heap, followed by the metadata array, all within an 8MB (2^23) block.
+ * The array is arranged as an array of shorts, one for each SMALL_QUANTUM in the heap.
+ * This means there are 16320 512-blocks and the array is 16320*2 bytes, which totals 8388480, leaving
+ * 128 bytes unused.
+ *
+ * The MSB of each short is set for the first quantum in a free block. The low 15 bits encode the
+ * block size (in SMALL_QUANTUM units), or are zero if the quantum is not the first in a block.
+ *
+ * The szone maintains an array of 32 freelists, each of which is used to hold free objects
+ * of the corresponding quantum size.
+ *
+ * A free block is laid out as:
+ *
+ * Offset (32-bit mode) (64-bit mode)
+ * 0x0 0x0 : previous
+ * 0x4 0x08 : next
+ * 0x8 0x10 : size (in quantum counts)
+ * end - 2 end - 2 : size (in quantum counts)
+ * end end
+ *
+ * All fields are pointer-sized, except for the size which is an unsigned short.
+ *
+ */
+
+#define SMALL_IS_FREE (1 << 15)
+
+#define SHIFT_SMALL_QUANTUM (SHIFT_TINY_QUANTUM + 5) // 9
+#define SMALL_QUANTUM (1 << SHIFT_SMALL_QUANTUM) // 512 bytes
+
+#define FOLLOWING_SMALL_PTR(ptr,msize) (((unsigned char *)(ptr)) + ((msize) << SHIFT_SMALL_QUANTUM))
+
+#define NUM_SMALL_SLOTS 32 // number of slots for free-lists
+
+/*
+ * We can only represent up to 1<<15 for msize; but we choose to stay even below that to avoid the
+ * convention msize=0 => msize = (1<<15)
+ */
+#define NUM_SMALL_BLOCKS 16320
+#define SHIFT_SMALL_CEIL_BLOCKS 14 // ceil(log2(NUM_SMALL_BLOCKs))
+#define NUM_SMALL_CEIL_BLOCKS (1 << SHIFT_SMALL_CEIL_BLOCKS)
+#define SMALL_BLOCKS_ALIGN (SHIFT_SMALL_CEIL_BLOCKS + SHIFT_SMALL_QUANTUM) // 23
+#define SMALL_ARRAY_SIZE (NUM_SMALL_BLOCKS * 2)
+#define SMALL_REGION_SIZE ((NUM_SMALL_BLOCKS * SMALL_QUANTUM + SMALL_ARRAY_SIZE + vm_page_size - 1) & ~ (vm_page_size - 1)) // data + meta data
+
+#define SMALL_PREVIOUS_MSIZE(ptr) ((msize_t *)(ptr))[-1]
+
+/*
+ * Convert between byte and msize units.
+ */
+#define SMALL_BYTES_FOR_MSIZE(_m) ((_m) << SHIFT_SMALL_QUANTUM)
+#define SMALL_MSIZE_FOR_BYTES(_b) ((_b) >> SHIFT_SMALL_QUANTUM)
+
+
+#define SMALL_REGION_ADDRESS(region) ((unsigned char *)region)
+#define SMALL_REGION_END(region) (SMALL_REGION_ADDRESS(region) + (NUM_SMALL_BLOCKS * SMALL_QUANTUM))
+
+/*
+ * Locate the heap base for a pointer known to be within a small region.
+ */
+#define SMALL_REGION_FOR_PTR(_p) ((void *)((uintptr_t)(_p) & ~((1 << SMALL_BLOCKS_ALIGN) - 1)))
+
+/*
+ * Locate the metadata base for a pointer known to be within a small region.
+ */
+#define SMALL_HEADER_START (NUM_SMALL_BLOCKS * SMALL_QUANTUM)
+#define SMALL_META_HEADER_FOR_PTR(_p) ((msize_t *)((uintptr_t)SMALL_REGION_FOR_PTR(_p) + SMALL_HEADER_START))
+
+/*
+ * Compute the metadata index for a pointer known to be within a small region.
+ */
+#define SMALL_META_INDEX_FOR_PTR(_p) (((uintptr_t)(_p) >> SHIFT_SMALL_QUANTUM) & (NUM_SMALL_CEIL_BLOCKS - 1))
+
+/*
+ * Find the metadata word for a pointer known to be within a small region.
+ */
+#define SMALL_METADATA_FOR_PTR(_p) (SMALL_META_HEADER_FOR_PTR(_p) + SMALL_META_INDEX_FOR_PTR(_p))
+
+/*
+ * Determine whether a pointer known to be within a small region points to memory which is free.
+ */
+#define SMALL_PTR_IS_FREE(_p) (*SMALL_METADATA_FOR_PTR(_p) & SMALL_IS_FREE)
+
+/*
+ * Extract the msize value for a pointer known to be within a small region.
+ */
+#define SMALL_PTR_SIZE(_p) (*SMALL_METADATA_FOR_PTR(_p) & ~SMALL_IS_FREE)
+
+#define PROTECT_SMALL 0 // Should be 0: 1 is too slow for normal use
+
+#define SMALL_CACHE 1
+#if !SMALL_CACHE
+#warning SMALL_CACHE turned off
+#endif
+
+/********************* DEFINITIONS for large and huge ***********************/
+
+#define LARGE_THRESHOLD (15 * 1024) // at or above this use "large"
+
+#if (LARGE_THRESHOLD > NUM_SMALL_SLOTS * SMALL_QUANTUM)
+#error LARGE_THRESHOLD should always be less than NUM_SMALL_SLOTS * SMALL_QUANTUM
+#endif
+
+#define VM_COPY_THRESHOLD (40 * 1024)
+ // When all memory is touched after a copy, vm_copy() is always a lose
+ // But if the memory is only read, vm_copy() wins over memmove() at 3 or 4 pages (on a G3/300MHz)
+ // This must be larger than LARGE_THRESHOLD
+
+/*
+ * Given a large_entry, return the address of the allocated block.
+ */
+#define LARGE_ENTRY_ADDRESS(entry) \
+ (void *)(((entry).address_and_num_pages >> vm_page_shift) << vm_page_shift)
+
+/*
+ * Given a large entry, return the number of pages or bytes in the allocated block.
+ */
+#define LARGE_ENTRY_NUM_PAGES(entry) \
+ ((entry).address_and_num_pages & (vm_page_size - 1))
+#define LARGE_ENTRY_SIZE(entry) \
+ (LARGE_ENTRY_NUM_PAGES(entry) << vm_page_shift)
+
+/*
+ * Compare a pointer with a large entry.
+ */
+#define LARGE_ENTRY_MATCHES(entry,ptr) \
+ ((((entry).address_and_num_pages - (uintptr_t)(ptr)) >> vm_page_shift) == 0)
+
+#define LARGE_ENTRY_IS_EMPTY(entry) (((entry).address_and_num_pages) == 0)
+
+typedef compact_range_t large_entry_t;
+typedef vm_range_t huge_entry_t;
+
+/*******************************************************************************
+ * Definitions for region hash
+ ******************************************************************************/
+
+typedef void * region_t;
+
+#define INITIAL_NUM_REGIONS 63 // Must be odd to hash well
+
+/********************* zone itself ************************/
+
+typedef struct {
+ malloc_zone_t basic_zone;
+ pthread_lock_t lock;
+ unsigned debug_flags;
+ void *log_address;
+
+ /* Regions for tiny objects */
+ size_t num_tiny_regions;
+ size_t num_tiny_regions_allocated;
+ region_t *tiny_regions; // hashed by location
+ region_t *last_tiny_region;
+ void *last_tiny_free; // low SHIFT_TINY_QUANTUM indicate the msize
+ unsigned tiny_bitmap; // cache of the 32 free lists
+ free_list_t *tiny_free_list[NUM_TINY_SLOTS]; // 31 free lists for 1*TINY_QUANTUM to 31*TINY_QUANTUM plus 1 for larger than 32*SMALL_QUANTUM
+ size_t tiny_bytes_free_at_end; // the last free region in the last block is treated as a big block in use that is not accounted for
+ unsigned num_tiny_objects;
+ size_t num_bytes_in_tiny_objects;
+
+ /* Regions for small objects */
+ size_t num_small_regions;
+ size_t num_small_regions_allocated;
+ region_t *small_regions; // hashed by location
+ region_t *last_small_region;
+ void *last_small_free; // low SHIFT_SMALL_QUANTUM indicate the msize
+ unsigned small_bitmap; // cache of the free list
+ free_list_t *small_free_list[NUM_SMALL_SLOTS];
+ size_t small_bytes_free_at_end; // the last free region in the last block is treated as a big block in use that is not accounted for
+ unsigned num_small_objects;
+ size_t num_bytes_in_small_objects;
+
+ /* large objects: vm_page_shift <= log2(size) < 2 *vm_page_shift */
+ unsigned num_large_objects_in_use;
+ unsigned num_large_entries;
+ large_entry_t *large_entries; // hashed by location; null entries don't count
+ size_t num_bytes_in_large_objects;
+
+ /* huge objects: log2(size) >= 2 *vm_page_shift */
+ unsigned num_huge_entries;
+ huge_entry_t *huge_entries;
+ size_t num_bytes_in_huge_objects;
+
+ /* Initial region list */
+ region_t initial_tiny_regions[INITIAL_NUM_REGIONS];
+ region_t initial_small_regions[INITIAL_NUM_REGIONS];
+} szone_t;
+
+#define SZONE_PAGED_SIZE ((sizeof(szone_t) + vm_page_size - 1) & ~ (vm_page_size - 1))
+
+#if DEBUG_MALLOC || DEBUG_CLIENT
+static void szone_sleep(void);
+#endif
+__private_extern__ void malloc_error_break(void);
+
+// msg prints after fmt, ...
+static void szone_error(szone_t *szone, const char *msg, const void *ptr, const char *fmt, ...) __printflike(4, 5);
+
+static void protect(void *address, size_t size, unsigned protection, unsigned debug_flags);
+static void *allocate_pages(szone_t *szone, size_t size, unsigned char align, unsigned debug_flags, int vm_page_label);
+static void deallocate_pages(szone_t *szone, void *addr, size_t size, unsigned debug_flags);
+static kern_return_t _szone_default_reader(task_t task, vm_address_t address, vm_size_t size, void **ptr);
+
+static INLINE void free_list_checksum(szone_t *szone, free_list_t *ptr, const char *msg) ALWAYSINLINE;
+static INLINE void free_list_set_checksum(szone_t *szone, free_list_t *ptr) ALWAYSINLINE;
+static INLINE uintptr_t free_list_checksum_ptr(void *p) ALWAYSINLINE;
+static INLINE void * free_list_unchecksum_ptr(ptr_union ptr) ALWAYSINLINE;
+static unsigned free_list_count(const free_list_t *ptr);
+
+static INLINE msize_t get_tiny_meta_header(const void *ptr, boolean_t *is_free) ALWAYSINLINE;
+static INLINE void set_tiny_meta_header_in_use(const void *ptr, msize_t msize) ALWAYSINLINE;
+static INLINE void set_tiny_meta_header_middle(const void *ptr) ALWAYSINLINE;
+static INLINE void set_tiny_meta_header_free(const void *ptr, msize_t msize) ALWAYSINLINE;
+static INLINE boolean_t tiny_meta_header_is_free(const void *ptr) ALWAYSINLINE;
+static INLINE void *tiny_previous_preceding_free(void *ptr, msize_t *prev_msize) ALWAYSINLINE;
+static void tiny_free_list_add_ptr(szone_t *szone, void *ptr, msize_t msize);
+static void tiny_free_list_remove_ptr(szone_t *szone, void *ptr, msize_t msize);
+static INLINE region_t *tiny_region_for_ptr_no_lock(szone_t *szone, const void *ptr) ALWAYSINLINE;
+static INLINE void tiny_free_no_lock(szone_t *szone, region_t *region, void *ptr, msize_t msize) ALWAYSINLINE;
+static void *tiny_malloc_from_region_no_lock(szone_t *szone, msize_t msize);
+static INLINE boolean_t try_realloc_tiny_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size) ALWAYSINLINE;
+static boolean_t tiny_check_region(szone_t *szone, region_t region);
+static kern_return_t tiny_in_use_enumerator(task_t task, void *context, unsigned type_mask, szone_t *szone, memory_reader_t reader, vm_range_recorder_t recorder);
+static void *tiny_malloc_from_free_list(szone_t *szone, msize_t msize);
+static INLINE void *tiny_malloc_should_clear(szone_t *szone, msize_t msize, boolean_t cleared_requested) ALWAYSINLINE;
+static INLINE void free_tiny(szone_t *szone, void *ptr, region_t *tiny_region) ALWAYSINLINE;
+static void print_tiny_free_list(szone_t *szone);
+static void print_tiny_region(boolean_t verbose, region_t region, size_t bytes_at_end);
+static boolean_t tiny_free_list_check(szone_t *szone, grain_t slot);
+
+static INLINE void small_meta_header_set_is_free(msize_t *meta_headers, unsigned index, msize_t msize) ALWAYSINLINE;
+static INLINE void small_meta_header_set_in_use(msize_t *meta_headers, msize_t index, msize_t msize) ALWAYSINLINE;
+static INLINE void small_meta_header_set_middle(msize_t *meta_headers, msize_t index) ALWAYSINLINE;
+static void small_free_list_add_ptr(szone_t *szone, void *ptr, msize_t msize);
+static void small_free_list_remove_ptr(szone_t *szone, void *ptr, msize_t msize);
+static INLINE region_t *small_region_for_ptr_no_lock(szone_t *szone, const void *ptr) ALWAYSINLINE;
+static INLINE void small_free_no_lock(szone_t *szone, region_t *region, void *ptr, msize_t msize) ALWAYSINLINE;
+static void *small_malloc_from_region_no_lock(szone_t *szone, msize_t msize);
+static INLINE boolean_t try_realloc_small_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size) ALWAYSINLINE;
+static boolean_t szone_check_small_region(szone_t *szone, region_t region);
+static kern_return_t small_in_use_enumerator(task_t task, void *context, unsigned type_mask, szone_t *szone, memory_reader_t reader, vm_range_recorder_t recorder);
+static void *small_malloc_from_free_list(szone_t *szone, msize_t msize);
+static INLINE void *small_malloc_should_clear(szone_t *szone, msize_t msize, boolean_t cleared_requested) ALWAYSINLINE;
+static INLINE void *small_malloc_cleared_no_lock(szone_t *szone, msize_t msize) ALWAYSINLINE;
+static INLINE void free_small(szone_t *szone, void *ptr, region_t *small_region) ALWAYSINLINE;
+static void print_small_free_list(szone_t *szone);
+static void print_small_region(szone_t *szone, boolean_t verbose, region_t region, size_t bytes_at_end);
+static boolean_t small_free_list_check(szone_t *szone, grain_t grain);
+
+static region_t * hash_lookup_region_no_lock(region_t *regions, size_t num_entries, region_t r);
+static void hash_region_insert_no_lock(region_t *regions, size_t num_entries, region_t r);
+static region_t * hash_regions_alloc_no_lock(szone_t *szone, size_t num_entries);
+static region_t * hash_regions_grow_no_lock(szone_t *szone, region_t *regions, size_t old_size, size_t *new_size);
+
+#if DEBUG_MALLOC
+static void large_debug_print(szone_t *szone);
+#endif
+static large_entry_t *large_entry_for_pointer_no_lock(szone_t *szone, const void *ptr);
+static void large_entry_insert_no_lock(szone_t *szone, large_entry_t range);
+static INLINE void large_entries_rehash_after_entry_no_lock(szone_t *szone, large_entry_t *entry) ALWAYSINLINE;
+static INLINE large_entry_t *large_entries_alloc_no_lock(szone_t *szone, unsigned num) ALWAYSINLINE;
+static void large_entries_free_no_lock(szone_t *szone, large_entry_t *entries, unsigned num, vm_range_t *range_to_deallocate);
+static large_entry_t * large_entries_grow_no_lock(szone_t *szone, vm_range_t *range_to_deallocate);
+static vm_range_t large_free_no_lock(szone_t *szone, large_entry_t *entry);
+static 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);
+static huge_entry_t *huge_entry_for_pointer_no_lock(szone_t *szone, const void *ptr);
+static boolean_t huge_entry_append(szone_t *szone, huge_entry_t huge);
+static kern_return_t huge_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t huge_entries_address, unsigned num_entries, memory_reader_t reader, vm_range_recorder_t recorder);
+static void *large_and_huge_malloc(szone_t *szone, size_t num_pages);
+static INLINE void free_large_or_huge(szone_t *szone, void *ptr) ALWAYSINLINE;
+static INLINE int try_realloc_large_or_huge_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size) ALWAYSINLINE;
+
+static void szone_free(szone_t *szone, void *ptr);
+static INLINE void *szone_malloc_should_clear(szone_t *szone, size_t size, boolean_t cleared_requested) ALWAYSINLINE;
+static void *szone_malloc(szone_t *szone, size_t size);
+static void *szone_calloc(szone_t *szone, size_t num_items, size_t size);
+static void *szone_valloc(szone_t *szone, size_t size);
+static size_t szone_size(szone_t *szone, const void *ptr);
+static void *szone_realloc(szone_t *szone, void *ptr, size_t new_size);
+static unsigned szone_batch_malloc(szone_t *szone, size_t size, void **results, unsigned count);
+static void szone_batch_free(szone_t *szone, void **to_be_freed, unsigned count);
+static void szone_destroy(szone_t *szone);
+static size_t szone_good_size(szone_t *szone, size_t size);
+
+static boolean_t szone_check_all(szone_t *szone, const char *function);
+static boolean_t szone_check(szone_t *szone);
+static kern_return_t szone_ptr_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t zone_address, memory_reader_t reader, vm_range_recorder_t recorder);
+static void szone_print(szone_t *szone, boolean_t verbose);
+static void szone_log(malloc_zone_t *zone, void *log_address);
+static void szone_force_lock(szone_t *szone);
+static void szone_force_unlock(szone_t *szone);
+
+static void szone_statistics(szone_t *szone, malloc_statistics_t *stats);
+
+static void *frozen_malloc(szone_t *zone, size_t new_size);
+static void *frozen_calloc(szone_t *zone, size_t num_items, size_t size);
+static void *frozen_valloc(szone_t *zone, size_t new_size);
+static void *frozen_realloc(szone_t *zone, void *ptr, size_t new_size);
+static void frozen_free(szone_t *zone, void *ptr);
+static void frozen_destroy(szone_t *zone);
+
+#if DEBUG_MALLOC
+# define LOG(szone,ptr) \
+ (szone->log_address && (((uintptr_t)szone->log_address == -1) || (szone->log_address == (void *)(ptr))))
+#else
+# define LOG(szone,ptr) 0
+#endif
+
+#define SZONE_LOCK(szone) \
+ do { \
+ LOCK(szone->lock); \
+ } while (0)
+
+#define SZONE_UNLOCK(szone) \
+ do { \
+ UNLOCK(szone->lock); \
+ } while (0)
+
+#define LOCK_AND_NOTE_LOCKED(szone,locked) \
+do { \
+ CHECK(szone, __PRETTY_FUNCTION__); \
+ locked = 1; SZONE_LOCK(szone); \
+} while (0)
+
+#if DEBUG_MALLOC || DEBUG_CLIENT
+# define CHECK(szone,fun) \
+ if ((szone)->debug_flags & CHECK_REGIONS) szone_check_all(szone, fun)
+#else
+# define CHECK(szone,fun) do {} while (0)
+#endif
+
+/********************* VERY LOW LEVEL UTILITIES ************************/
+
+#if DEBUG_MALLOC || DEBUG_CLIENT
+static void
+szone_sleep(void)
+{
+
+ if (getenv("MallocErrorSleep")) {
+ _malloc_printf(ASL_LEVEL_NOTICE, "*** sleeping to help debug\n");
+ sleep(3600); // to help debug
+ }
+}
+#endif
+
+// msg prints after fmt, ...
+static __attribute__((noinline)) void
+szone_error(szone_t *szone, const char *msg, const void *ptr, const char *fmt, ...)
+{
+ va_list ap;
+ _SIMPLE_STRING b = _simple_salloc();
+
+ if (szone) SZONE_UNLOCK(szone);
+ if (b) {
+ if (fmt) {
+ va_start(ap, fmt);
+ _simple_vsprintf(b, fmt, ap);
+ va_end(ap);
+ }
+ if (ptr) {
+ _simple_sprintf(b, "*** error for object %p: %s\n", ptr, msg);
+ } else {
+ _simple_sprintf(b, "*** error: %s\n", msg);
+ }
+ malloc_printf("%s*** set a breakpoint in malloc_error_break to debug\n", _simple_string(b));
+ _simple_sfree(b);
+ } else {
+ /*
+ * Should only get here if vm_allocate() can't get a single page of
+ * memory, implying _simple_asl_log() would also fail. So we just
+ * print to the file descriptor.
+ */
+ if (fmt) {
+ va_start(ap, fmt);
+ _malloc_vprintf(MALLOC_PRINTF_NOLOG, fmt, ap);
+ va_end(ap);
+ }
+ if (ptr) {
+ _malloc_printf(MALLOC_PRINTF_NOLOG, "*** error for object %p: %s\n", ptr, msg);
+ } else {
+ _malloc_printf(MALLOC_PRINTF_NOLOG, "*** error: %s\n", msg);
+ }
+ _malloc_printf(MALLOC_PRINTF_NOLOG, "*** set a breakpoint in malloc_error_break to debug\n");
+ }
+ malloc_error_break();
+#if DEBUG_MALLOC
+ szone_print(szone, 1);
+ szone_sleep();
+#endif
+#if DEBUG_CLIENT
+ szone_sleep();
+#endif
+ if (szone->debug_flags & SCALABLE_MALLOC_ABORT_ON_ERROR) abort();
+}
+
+static void
+protect(void *address, size_t size, unsigned protection, unsigned debug_flags)
+{
+ kern_return_t err;
+
+ if (!(debug_flags & SCALABLE_MALLOC_DONT_PROTECT_PRELUDE)) {
+ err = vm_protect(mach_task_self(), (vm_address_t)(uintptr_t)address - vm_page_size, vm_page_size, 0, protection);
+ if (err) {
+ malloc_printf("*** can't protect(%p) region for prelude guard page at %p\n",
+ protection,address - (1 << vm_page_shift));
+ }
+ }
+ if (!(debug_flags & SCALABLE_MALLOC_DONT_PROTECT_POSTLUDE)) {
+ err = vm_protect(mach_task_self(), (vm_address_t)(uintptr_t)address + size, vm_page_size, 0, protection);
+ if (err) {
+ malloc_printf("*** can't protect(%p) region for postlude guard page at %p\n",
+ protection, address + size);
+ }
+ }
+}
+
+static void *
+allocate_pages(szone_t *szone, size_t size, unsigned char align, unsigned debug_flags, int vm_page_label)
+{
+ // align specifies a desired alignment (as a log) or 0 if no alignment requested
+ void *vm_addr;
+ uintptr_t addr, aligned_address;
+ boolean_t add_guard_pages = debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES;
+ size_t allocation_size = round_page(size);
+ size_t delta;
+
+ if (align) add_guard_pages = 0; // too cumbersome to deal with that
+ if (!allocation_size) allocation_size = 1 << vm_page_shift;
+ if (add_guard_pages) allocation_size += 2 * (1 << vm_page_shift);
+ if (align) allocation_size += (size_t)1 << align;
+ vm_addr = mmap(0, allocation_size, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, VM_MAKE_TAG(vm_page_label), 0);
+ if ((uintptr_t)vm_addr == -1) {
+ szone_error(szone, "can't allocate region", NULL, "*** mmap(size=%lld) failed (error code=%d)\n", (long long)allocation_size, errno);
+ return NULL;
+ }
+ addr = (uintptr_t)vm_addr;
+ if (align) {
+ aligned_address = (addr + ((uintptr_t)1 << align) - 1) & ~ (((uintptr_t)1 << align) - 1);
+ if (aligned_address != addr) {
+ delta = aligned_address - addr;
+ if (munmap((void *)addr, delta) == -1)
+ malloc_printf("*** freeing unaligned header failed with %d\n", errno);
+ addr = aligned_address;
+ allocation_size -= delta;
+ }
+ if (allocation_size > size) {
+ if (munmap((void *)(addr + size), allocation_size - size) == -1)
+ malloc_printf("*** freeing unaligned footer failed with %d\n", errno);
+ }
+ }
+ if (add_guard_pages) {
+ addr += (uintptr_t)1 << vm_page_shift;
+ protect((void *)addr, size, 0, debug_flags);
+ }
+ return (void *)addr;
+}
+
+static void
+deallocate_pages(szone_t *szone, void *addr, size_t size, unsigned debug_flags)
+{
+ int err;
+ boolean_t add_guard_pages = debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES;
+
+ if (add_guard_pages) {
+ addr -= 1 << vm_page_shift;
+ size += 2 * (1 << vm_page_shift);
+ }
+ err = munmap(addr, size);
+ if ((err == -1) && szone)
+ szone_error(szone, "Can't deallocate_pages region", addr, NULL);
+}
+
+static kern_return_t
+_szone_default_reader(task_t task, vm_address_t address, vm_size_t size, void **ptr)
+{
+ *ptr = (void *)address;
+ return 0;
+}
+
+/********************* FREE LIST UTILITIES ************************/
+
+// A free list entry is comprised of a pair of pointers, previous and next.
+// Because the free list entries are previously freed objects, there is a
+// non-zero chance that a misbehaved program will write to an allocated object
+// after it has called free() on the pointer. This write would then potentially
+// corrupt the previous and next pointers, leading to a crash. In order to
+// detect this case, we take advantage of the fact that pointers are known to
+// be at least 16 byte aligned, and thus have at least 4 trailing zero bits.
+// When an entry is added to the free list, the previous and next pointers are
+// shifted right by 2 bits, and then have the high and low 2 bits set, to act
+// as guard bits. Before accessing a free list object, we verify that these
+// bits are still set, and log an error if they are not.
+
+static INLINE void
+free_list_checksum(szone_t *szone, free_list_t *ptr, const char *msg)
+{
+ uintptr_t ptrs = ptr->previous.u & ptr->next.u;
+
+#ifdef __LP64__
+ ptrs = (ptrs << 2) | (ptrs >> (64-2));
+#else
+ ptrs = (ptrs << 2) | (ptrs >> (32-2));
+#endif
+
+ if ((ptrs & 15) != 15)
+ szone_error(szone, "incorrect checksum for freed object "
+ "- object was probably modified after being freed.", ptr, NULL);
+}
+
+static INLINE uintptr_t
+free_list_checksum_ptr(void *p)
+{
+ ptr_union ptr;
+ ptr.p = p;
+
+#ifdef __LP64__
+ return (ptr.u >> 2) | 0xC000000000000003ULL;
+#else
+ return (ptr.u >> 2) | 0xC0000003U;
+#endif
+}
+
+static INLINE void *
+free_list_unchecksum_ptr(ptr_union ptr)
+{
+ uintptr_t u = (ptr.u >> 2) << 4;
+ return (void *)u;
+}
+
+static INLINE void
+free_list_set_checksum(szone_t *szone, free_list_t *ptr)
+{
+ ptr->previous.u = free_list_checksum_ptr(ptr->previous.p);
+ ptr->next.u = free_list_checksum_ptr(ptr->next.p);
+}
+
+static unsigned
+free_list_count(const free_list_t *ptr)
+{
+ unsigned count = 0;
+
+ while (ptr) {
+ count++;
+ ptr = free_list_unchecksum_ptr(ptr->next);
+ }
+ return count;
+}
+
+/* XXX inconsistent use of BITMAP32 and BITARRAY operations could be cleaned up */
+
+#define BITMAP32_SET(bitmap,bit) (bitmap |= 1 << (bit))
+#define BITMAP32_CLR(bitmap,bit) (bitmap &= ~ (1 << (bit)))
+#define BITMAP32_BIT(bitmap,bit) ((bitmap >> (bit)) & 1)
+
+/* returns bit # of least-significant one bit, starting at 0 (undefined if !bitmap) */
+#define BITMAP32_CTZ(bitmap) (__builtin_ctz(bitmap))
+
+/********************* TINY FREE LIST UTILITIES ************************/
+
+// We encode the meta-headers as follows:
+// Each quantum has an associated set of 2 bits:
+// block_header when 1 says this block is the beginning of a block
+// in_use when 1 says this block is in use
+// so a block in use of size 3 is 1-1 0-X 0-X
+// for a free block TINY_FREE_SIZE(ptr) carries the size and the bits are 1-0 X-X X-X
+// for a block middle the bits are 0-0
+
+// Attention double evaluation for these
+#define BITARRAY_SET(bits,index) (bits[index>>3] |= (1 << (index & 7)))
+#define BITARRAY_CLR(bits,index) (bits[index>>3] &= ~(1 << (index & 7)))
+#define BITARRAY_BIT(bits,index) (((bits[index>>3]) >> (index & 7)) & 1)
+
+// Following is for start<8 and end<=start+32
+static void ALWAYSINLINE
+bitarray_mclr(void *bits, unsigned start, unsigned end) {
+ unsigned word = OSReadLittleInt32(bits, 0);
+ unsigned mask = (0xFFFFFFFFU >> (31 - start)) >> 1;
+
+ if (end > 31) {
+ unsigned char *bytes = (unsigned char *)bits;
+ bytes[4] &= ~((1 << (end - 32)) - 1);
+ } else {
+ mask |= (0xFFFFFFFF << end);
+ }
+ OSWriteLittleInt32(bits, 0, word & mask);
+}
+
+/*
+ * Obtain the size of a free tiny block (in msize_t units).
+ */
+static msize_t
+get_tiny_free_size(const void *ptr)
+{
+ void *next_block = (void *)((uintptr_t)ptr + TINY_QUANTUM);
+ void *region_end = TINY_REGION_END(TINY_REGION_FOR_PTR(ptr));
+
+ // check whether the next block is outside the tiny region or a block header
+ // if so, then the size of this block is one, and there is no stored size.
+ if (next_block < region_end)
+ {
+ unsigned char *next_header = TINY_BLOCK_HEADER_FOR_PTR(next_block);
+ msize_t next_index = TINY_INDEX_FOR_PTR(next_block);
+
+ if (!BITARRAY_BIT(next_header, next_index))
+ return TINY_FREE_SIZE(ptr);
+ }
+ return 1;
+}
+
+/*
+ * Get the size of the previous free block, which is stored in the last two
+ * bytes of the block. If the previous block is not free, then the result is
+ * undefined.
+ */
+static msize_t
+get_tiny_previous_free_msize(const void *ptr)
+{
+ // check whether the previous block is in the tiny region and a block header
+ // if so, then the size of the previous block is one, and there is no stored
+ // size.
+ if (ptr != TINY_REGION_FOR_PTR(ptr))
+ {
+ void *prev_block = (void *)((uintptr_t)ptr - TINY_QUANTUM);
+ unsigned char *prev_header = TINY_BLOCK_HEADER_FOR_PTR(prev_block);
+ msize_t prev_index = TINY_INDEX_FOR_PTR(prev_block);
+ if (BITARRAY_BIT(prev_header, prev_index))
+ return 1;
+ return TINY_PREVIOUS_MSIZE(ptr);
+ }
+ // don't read possibly unmapped memory before the beginning of the region
+ return 0;
+}
+
+static INLINE msize_t
+get_tiny_meta_header(const void *ptr, boolean_t *is_free)
+{
+ // returns msize and is_free
+ // may return 0 for the msize component (meaning 65536)
+ unsigned char *block_header;
+ unsigned char *in_use;
+ msize_t index;
+ unsigned byte_index;
+
+ block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
+ index = TINY_INDEX_FOR_PTR(ptr);
+ byte_index = index >> 3;
+
+ block_header += byte_index;
+ index &= 7;
+ *is_free = 0;
+ if (!BITMAP32_BIT(*block_header, index))
+ return 0;
+ in_use = TINY_INUSE_FOR_HEADER(block_header);
+ if (!BITMAP32_BIT(*in_use, index)) {
+ *is_free = 1;
+ return get_tiny_free_size(ptr);
+ }
+ uint32_t *addr = (uint32_t *)((uintptr_t)block_header & ~3);
+ uint32_t word0 = OSReadLittleInt32(addr, 0) >> index;
+ uint32_t word1 = OSReadLittleInt32(addr, 4) << (8 - index);
+ uint32_t bits = (((uintptr_t)block_header & 3) * 8); // precision loss on LP64 OK here
+ uint32_t word = (word0 >> bits) | (word1 << (24 - bits));
+ uint32_t result = ffs(word >> 1);
+ return result;
+}
+
+static INLINE void
+set_tiny_meta_header_in_use(const void *ptr, msize_t msize)
+{
+ unsigned char *block_header;
+ unsigned char *in_use;
+ msize_t index;
+ unsigned byte_index;
+ msize_t clr_msize;
+ unsigned end_bit;
+
+ block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
+ index = TINY_INDEX_FOR_PTR(ptr);
+ byte_index = index >> 3;
+
+#if DEBUG_MALLOC
+ if (msize >= 32)
+ malloc_printf("set_tiny_meta_header_in_use() invariant broken %p %d\n", ptr, msize);
+ if ((unsigned)index + (unsigned)msize > 0x10000)
+ malloc_printf("set_tiny_meta_header_in_use() invariant broken (2) %p %d\n", ptr, msize);
+#endif
+ block_header += byte_index;
+ index &= 7;
+ BITMAP32_SET(*block_header, index);
+ in_use = TINY_INUSE_FOR_HEADER(block_header);
+ BITMAP32_SET(*in_use, index);
+ index++;
+ clr_msize = msize-1;
+ if (clr_msize) {
+ byte_index = index >> 3;
+ block_header += byte_index; in_use += byte_index;
+ index &= 7;
+ end_bit = index + clr_msize;
+ bitarray_mclr(block_header, index, end_bit);
+ bitarray_mclr(in_use, index, end_bit);
+ }
+ BITARRAY_SET(block_header, index+clr_msize); // we set the block_header bit for the following block to reaffirm next block is a block
+#if DEBUG_MALLOC
+ {
+ boolean_t ff;
+ msize_t mf;
+
+ mf = get_tiny_meta_header(ptr, &ff);
+ if (msize != mf) {
+ malloc_printf("setting header for tiny in_use %p : %d\n", ptr, msize);
+ malloc_printf("reading header for tiny %p : %d %d\n", ptr, mf, ff);
+ }
+ }
+#endif
+}
+
+static INLINE void
+set_tiny_meta_header_middle(const void *ptr)
+{
+ // indicates this block is in the middle of an in use block
+ unsigned char *block_header;
+ unsigned char *in_use;
+ msize_t index;
+
+ block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
+ in_use = TINY_INUSE_FOR_HEADER(block_header);
+ index = TINY_INDEX_FOR_PTR(ptr);
+
+ BITARRAY_CLR(block_header, index);
+ BITARRAY_CLR(in_use, index);
+}
+
+static INLINE void
+set_tiny_meta_header_free(const void *ptr, msize_t msize)
+{
+ // !msize is acceptable and means 65536
+ unsigned char *block_header;
+ unsigned char *in_use;
+ msize_t index;
+
+ block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
+ in_use = TINY_INUSE_FOR_HEADER(block_header);
+ index = TINY_INDEX_FOR_PTR(ptr);
+
+#if DEBUG_MALLOC
+ if ((unsigned)index + (unsigned)msize > 0x10000) {
+ malloc_printf("setting header for tiny free %p msize too large: %d\n", ptr, msize);
+ }
+#endif
+ BITARRAY_SET(block_header, index);
+ BITARRAY_CLR(in_use, index);
+ // mark the end of this block if msize is > 1. For msize == 0, the whole
+ // region is free, so there is no following block. For msize == 1, there is
+ // no space to write the size on 64 bit systems. The size for 1 quantum
+ // blocks is computed from the metadata bitmaps.
+ if (msize > 1) {
+ void *follower = FOLLOWING_TINY_PTR(ptr, msize);
+ TINY_PREVIOUS_MSIZE(follower) = msize;
+ TINY_FREE_SIZE(ptr) = msize;
+ }
+ if (msize == 0) {
+ TINY_FREE_SIZE(ptr) = msize;
+ }
+#if DEBUG_MALLOC
+ boolean_t ff;
+ msize_t mf = get_tiny_meta_header(ptr, &ff);
+ if ((msize != mf) || !ff) {
+ malloc_printf("setting header for tiny free %p : %u\n", ptr, msize);
+ malloc_printf("reading header for tiny %p : %u %u\n", ptr, mf, ff);
+ }
+#endif
+}
+
+static INLINE boolean_t
+tiny_meta_header_is_free(const void *ptr)
+{
+ unsigned char *block_header;
+ unsigned char *in_use;
+ msize_t index;
+
+ block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
+ in_use = TINY_INUSE_FOR_HEADER(block_header);
+ index = TINY_INDEX_FOR_PTR(ptr);
+ if (!BITARRAY_BIT(block_header, index))
+ return 0;
+ return !BITARRAY_BIT(in_use, index);
+}
+
+static INLINE void *
+tiny_previous_preceding_free(void *ptr, msize_t *prev_msize)
+{
+ // returns the previous block, assuming and verifying it's free
+ unsigned char *block_header;
+ unsigned char *in_use;
+ msize_t index;
+ msize_t previous_msize;
+ msize_t previous_index;
+ void *previous_ptr;
+
+ block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
+ in_use = TINY_INUSE_FOR_HEADER(block_header);
+ index = TINY_INDEX_FOR_PTR(ptr);
+
+ if (!index)
+ return NULL;
+ if ((previous_msize = get_tiny_previous_free_msize(ptr)) > index)
+ return NULL;
+
+ previous_index = index - previous_msize;
+ previous_ptr = (void *)(TINY_REGION_FOR_PTR(ptr) + TINY_BYTES_FOR_MSIZE(previous_index));
+ if (!BITARRAY_BIT(block_header, previous_index))
+ return NULL;
+ if (BITARRAY_BIT(in_use, previous_index))
+ return NULL;
+ if (get_tiny_free_size(previous_ptr) != previous_msize)
+ return NULL;
+
+ // conservative check did match true check
+ *prev_msize = previous_msize;
+ return previous_ptr;
+}
+
+/*
+ * Adds an item to the proper free list, and also marks the meta-header of the
+ * block properly.
+ * Assumes szone has been locked
+ */
+static void
+tiny_free_list_add_ptr(szone_t *szone, void *ptr, msize_t msize)
+{
+ grain_t slot = (!msize || (msize >= NUM_TINY_SLOTS)) ? NUM_TINY_SLOTS - 1 : msize - 1;
+ free_list_t *free_ptr = ptr;
+ free_list_t *free_head = szone->tiny_free_list[slot];
+
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in %s, ptr=%p, msize=%d\n", __FUNCTION__, ptr, msize);
+ }
+ if (((uintptr_t)ptr) & (TINY_QUANTUM - 1)) {
+ szone_error(szone, "tiny_free_list_add_ptr: Unaligned ptr", ptr, NULL);
+ }
+#endif
+ set_tiny_meta_header_free(ptr, msize);
+ if (free_head) {
+ free_list_checksum(szone, free_head, __PRETTY_FUNCTION__);
+#if DEBUG_MALLOC
+ if (free_list_unchecksum_ptr(free_head->previous)) {
+ szone_error(szone, "tiny_free_list_add_ptr: Internal invariant broken (free_head->previous)", ptr,
+ "ptr=%p slot=%d free_head=%p previous=%p\n", ptr, slot, free_head, free_head->previous.p);
+ }
+ if (! tiny_meta_header_is_free(free_head)) {
+ szone_error(szone, "tiny_free_list_add_ptr: Internal invariant broken (free_head is not a free pointer)", ptr,
+ "ptr=%p slot=%d free_head=%p\n", ptr, slot, free_head);
+ }
+#endif
+ free_head->previous.u = free_list_checksum_ptr(free_ptr);
+ } else {
+ BITMAP32_SET(szone->tiny_bitmap, slot);
+ }
+ free_ptr->previous.p = NULL;
+ free_ptr->next.p = free_head;
+ free_list_set_checksum(szone, free_ptr);
+ szone->tiny_free_list[slot] = free_ptr;
+}
+
+/*
+ * Removes the item pointed to by ptr in the proper free list.
+ * Assumes szone has been locked
+ */
+static INLINE void
+tiny_free_list_remove_ptr(szone_t *szone, void *ptr, msize_t msize)
+{
+ grain_t slot = (!msize || (msize >= NUM_TINY_SLOTS)) ? NUM_TINY_SLOTS - 1 : msize - 1;
+ free_list_t *free_ptr = ptr, *next, *previous;
+ free_list_checksum(szone, free_ptr, __PRETTY_FUNCTION__);
+
+ next = free_list_unchecksum_ptr(free_ptr->next);
+ previous = free_list_unchecksum_ptr(free_ptr->previous);
+
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("In %s, ptr=%p, msize=%d\n", __FUNCTION__, ptr, msize);
+ }
+#endif
+ if (!previous) {
+ // The block to remove is the head of the free list
+#if DEBUG_MALLOC
+ if (szone->tiny_free_list[slot] != ptr) {
+ szone_error(szone, "tiny_free_list_remove_ptr: Internal invariant broken (szone->tiny_free_list[slot])", ptr,
+ "ptr=%p slot=%d msize=%d szone->tiny_free_list[slot]=%p\n",
+ ptr, slot, msize, szone->tiny_free_list[slot]);
+ return;
+ }
+#endif
+ szone->tiny_free_list[slot] = next;
+ if (!next) BITMAP32_CLR(szone->tiny_bitmap, slot);
+ } else {
+ // We know free_ptr is already checksummed, so we don't need to do it
+ // again.
+ previous->next = free_ptr->next;
+ }
+ if (next) {
+ // We know free_ptr is already checksummed, so we don't need to do it
+ // again.
+ next->previous = free_ptr->previous;
+ }
+}
+
+/*
+ * tiny_region_for_ptr_no_lock - Returns the tiny region containing the pointer,
+ * or NULL if not found.
+ */
+static INLINE region_t *
+tiny_region_for_ptr_no_lock(szone_t *szone, const void *ptr)
+{
+ return hash_lookup_region_no_lock(szone->tiny_regions,
+ szone->num_tiny_regions_allocated,
+ TINY_REGION_FOR_PTR(ptr));
+}
+
+static INLINE void
+tiny_free_no_lock(szone_t *szone, region_t *region, void *ptr, msize_t msize)
+{
+ size_t original_size = TINY_BYTES_FOR_MSIZE(msize);
+ void *next_block = ((char *)ptr + original_size);
+ msize_t previous_msize;
+ void *previous;
+ msize_t next_msize;
+ free_list_t *big_free_block;
+ free_list_t *after_next_block;
+ free_list_t *before_next_block;
+
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in tiny_free_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
+ }
+ if (! msize) {
+ szone_error(szone, "trying to free tiny block that is too small", ptr,
+ "in tiny_free_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
+ }
+#endif
+ // We try to coalesce this block with the preceeding one
+ previous = tiny_previous_preceding_free(ptr, &previous_msize);
+ if (previous) {
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr) || LOG(szone,previous)) {
+ malloc_printf("in tiny_free_no_lock(), coalesced backwards for %p previous=%p\n", ptr, previous);
+ }
+#endif
+ // clear the meta_header since this is no longer the start of a block
+ set_tiny_meta_header_middle(ptr);
+ tiny_free_list_remove_ptr(szone, previous, previous_msize);
+ ptr = previous;
+ msize += previous_msize;
+ }
+ // We try to coalesce with the next block
+ if ((next_block < TINY_REGION_END(*region)) && tiny_meta_header_is_free(next_block)) {
+ next_msize = get_tiny_free_size(next_block);
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr) || LOG(szone, next_block)) {
+ malloc_printf("in tiny_free_no_lock(), for ptr=%p, msize=%d coalesced forward=%p next_msize=%d\n",
+ ptr, msize, next_block, next_msize);
+ }
+#endif
+ // If we are coalescing with the next block, and the next block is in
+ // the last slot of the free list, then we optimize this case here to
+ // avoid removing next_block from the slot 31 and then adding ptr back
+ // to slot 31.
+ if (next_msize >= NUM_TINY_SLOTS) {
+ msize += next_msize;
+ big_free_block = (free_list_t *)next_block;
+ free_list_checksum(szone, big_free_block, __PRETTY_FUNCTION__);
+ after_next_block = free_list_unchecksum_ptr(big_free_block->next);
+ before_next_block = free_list_unchecksum_ptr(big_free_block->previous);
+ if (!before_next_block) {
+ szone->tiny_free_list[NUM_TINY_SLOTS-1] = ptr;
+ } else {
+ before_next_block->next.u = free_list_checksum_ptr(ptr);
+ }
+ if (after_next_block) {
+ after_next_block->previous.u = free_list_checksum_ptr(ptr);
+ }
+ // we don't need to checksum these since they are already checksummed
+ ((free_list_t *)ptr)->previous = big_free_block->previous;
+ ((free_list_t *)ptr)->next = big_free_block->next;
+
+ // clear the meta_header to enable coalescing backwards
+ set_tiny_meta_header_middle(big_free_block);
+ set_tiny_meta_header_free(ptr, msize);
+ goto tiny_free_ending;
+ }
+ tiny_free_list_remove_ptr(szone, next_block, next_msize);
+ set_tiny_meta_header_middle(next_block); // clear the meta_header to enable coalescing backwards
+ msize += next_msize;
+ }
+#if !TINY_CACHE
+ // The tiny cache already scribbles free blocks as they go through the
+ // cache, so we do not need to do it here.
+ if ((szone->debug_flags & SCALABLE_MALLOC_DO_SCRIBBLE) && msize) {
+ memset(ptr, 0x55, TINY_BYTES_FOR_MSIZE(msize));
+ }
+#endif
+ tiny_free_list_add_ptr(szone, ptr, msize);
+ tiny_free_ending:
+ // When in proper debug mode we write on the memory to help debug memory smashers
+ szone->num_tiny_objects--;
+ szone->num_bytes_in_tiny_objects -= original_size; // we use original_size and not msize to avoid double counting the coalesced blocks
+}
+
+// Allocates from the last region or a freshly allocated region
+static void *
+tiny_malloc_from_region_no_lock(szone_t *szone, msize_t msize)
+{
+ void *last_block, *ptr, *aligned_address;
+ unsigned char *last_header;
+ msize_t last_msize, last_index;
+
+ // Before anything we transform any remaining tiny_bytes_free_at_end into a
+ // regular free block. We take special care here to update the bitfield
+ // information, since we are bypassing the normal free codepath. If there
+ // is more than one quanta worth of memory in tiny_bytes_free_at_end, then
+ // there will be two block headers:
+ // 1) header for the free space at end, msize = 1
+ // 2) header inserted by set_tiny_meta_header_in_use after block
+ // We must clear the second one so that when the free block's size is
+ // queried, we do not think the block is only 1 quantum in size because
+ // of the second set header bit.
+ if (szone->tiny_bytes_free_at_end) {
+ last_block = TINY_REGION_END(szone->last_tiny_region) - szone->tiny_bytes_free_at_end;
+ last_msize = TINY_MSIZE_FOR_BYTES(szone->tiny_bytes_free_at_end);
+ last_header = TINY_BLOCK_HEADER_FOR_PTR(last_block);
+ last_index = TINY_INDEX_FOR_PTR(last_block);
+
+ if (last_index != (NUM_TINY_BLOCKS - 1))
+ BITARRAY_CLR(last_header, last_index + 1);
+
+ tiny_free_list_add_ptr(szone, last_block, last_msize);
+ szone->tiny_bytes_free_at_end = 0;
+ }
+ // time to create a new region
+ aligned_address = allocate_pages(szone, TINY_REGION_SIZE, TINY_BLOCKS_ALIGN, 0, VM_MEMORY_MALLOC_TINY);
+ if (!aligned_address) // out of memory!
+ return NULL;
+ // We set the padding after block_header to be all 1
+ ((uint32_t *)(aligned_address + TINY_HEADER_START + (NUM_TINY_BLOCKS >> 3)))[0] = ~0;
+
+ // Check to see if the hash ring of tiny regions needs to grow. Try to
+ // avoid the hash ring becoming too dense.
+ if (szone->num_tiny_regions_allocated < (2 * szone->num_tiny_regions)) {
+ region_t *new_regions;
+ size_t new_size;
+ new_regions = hash_regions_grow_no_lock(szone, szone->tiny_regions,
+ szone->num_tiny_regions_allocated,
+ &new_size);
+ // Do not deallocate the current tiny_regions allocation since someone may
+ // be iterating it. Instead, just leak it.
+ szone->tiny_regions = new_regions;
+ szone->num_tiny_regions_allocated = new_size;
+ }
+ // Insert the new region into the hash ring, and update malloc statistics
+ hash_region_insert_no_lock(szone->tiny_regions,
+ szone->num_tiny_regions_allocated,
+ aligned_address);
+ szone->last_tiny_region = aligned_address;
+
+ szone->num_tiny_regions++;
+ ptr = aligned_address;
+ set_tiny_meta_header_in_use(ptr, msize);
+ szone->num_tiny_objects++;
+ szone->num_bytes_in_tiny_objects += TINY_BYTES_FOR_MSIZE(msize);
+
+ // We put a header on the last block so that it appears in use (for coalescing, etc...)
+ set_tiny_meta_header_in_use(ptr + TINY_BYTES_FOR_MSIZE(msize), 1);
+ szone->tiny_bytes_free_at_end = TINY_BYTES_FOR_MSIZE(NUM_TINY_BLOCKS - msize);
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in tiny_malloc_from_region_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
+ }
+#endif
+ return ptr;
+}
+
+static INLINE boolean_t
+try_realloc_tiny_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size)
+{
+ // returns 1 on success
+ msize_t index;
+ msize_t old_msize;
+ unsigned next_index;
+ void *next_block;
+ boolean_t is_free;
+ msize_t next_msize, coalesced_msize, leftover_msize;
+ void *leftover;
+
+ index = TINY_INDEX_FOR_PTR(ptr);
+ old_msize = TINY_MSIZE_FOR_BYTES(old_size);
+ next_index = index + old_msize;
+
+ if (next_index >= NUM_TINY_BLOCKS) {
+ return 0;
+ }
+ next_block = (char *)ptr + old_size;
+ SZONE_LOCK(szone);
+ is_free = tiny_meta_header_is_free(next_block);
+ if (!is_free) {
+ SZONE_UNLOCK(szone);
+ return 0; // next_block is in use;
+ }
+ next_msize = get_tiny_free_size(next_block);
+ if (old_size + TINY_MSIZE_FOR_BYTES(next_msize) < new_size) {
+ SZONE_UNLOCK(szone);
+ return 0; // even with next block, not enough
+ }
+ tiny_free_list_remove_ptr(szone, next_block, next_msize);
+ set_tiny_meta_header_middle(next_block); // clear the meta_header to enable coalescing backwards
+ coalesced_msize = TINY_MSIZE_FOR_BYTES(new_size - old_size + TINY_QUANTUM - 1);
+ leftover_msize = next_msize - coalesced_msize;
+ if (leftover_msize) {
+ leftover = next_block + TINY_BYTES_FOR_MSIZE(coalesced_msize);
+ tiny_free_list_add_ptr(szone, leftover, leftover_msize);
+ }
+ set_tiny_meta_header_in_use(ptr, old_msize + coalesced_msize);
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in try_realloc_tiny_in_place(), ptr=%p, msize=%d\n", ptr, old_msize + coalesced_msize);
+ }
+#endif
+ szone->num_bytes_in_tiny_objects += TINY_BYTES_FOR_MSIZE(coalesced_msize);
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ return 1;
+}
+
+static boolean_t
+tiny_check_region(szone_t *szone, region_t region)
+{
+ uintptr_t start, ptr, region_end;
+ boolean_t prev_free = 0;
+ boolean_t is_free;
+ msize_t msize;
+ free_list_t *free_head;
+ void *follower, *previous, *next;
+
+ /* establish region limits */
+ start = (uintptr_t)TINY_REGION_ADDRESS(region);
+ ptr = start;
+ region_end = (uintptr_t)TINY_REGION_END(region);
+
+ /*
+ * The last region may have a trailing chunk which has not been converted into inuse/freelist
+ * blocks yet.
+ */
+ if (region == szone->last_tiny_region)
+ region_end -= szone->tiny_bytes_free_at_end;
+
+
+ /*
+ * Scan blocks within the region.
+ */
+ while (ptr < region_end) {
+ /*
+ * If the first block is free, and its size is 65536 (msize = 0) then the entire region is
+ * free.
+ */
+ msize = get_tiny_meta_header((void *)ptr, &is_free);
+ if (is_free && !msize && (ptr == start)) {
+ return 1;
+ }
+
+ /*
+ * If the block's size is 65536 (msize = 0) then since we're not the first entry the size is
+ * corrupt.
+ */
+ if (!msize) {
+ malloc_printf("*** invariant broken for tiny block %p this msize=%d - size is too small\n",
+ ptr, msize);
+ return 0;
+ }
+
+ if (!is_free) {
+ /*
+ * In use blocks cannot be more than 31 quanta large.
+ */
+ prev_free = 0;
+ if (msize > 31 * TINY_QUANTUM) {
+ malloc_printf("*** invariant broken for %p this tiny msize=%d[%p] - size is too large\n",
+ ptr, msize, msize);
+ return 0;
+ }
+ /* move to next block */
+ ptr += TINY_BYTES_FOR_MSIZE(msize);
+ } else {
+ /*
+ * Free blocks must have been coalesced, we cannot have a free block following another
+ * free block.
+ */
+ if (prev_free) {
+ malloc_printf("*** invariant broken for free block %p this tiny msize=%d: two free blocks in a row\n",
+ ptr, msize);
+ return 0;
+ }
+ prev_free = 1;
+ /*
+ * Check the integrity of this block's entry in its freelist.
+ */
+ free_head = (free_list_t *)ptr;
+ free_list_checksum(szone, free_head, __PRETTY_FUNCTION__);
+ previous = free_list_unchecksum_ptr(free_head->previous);
+ next = free_list_unchecksum_ptr(free_head->next);
+ if (previous && !tiny_meta_header_is_free(previous)) {
+ malloc_printf("*** invariant broken for %p (previous %p is not a free pointer)\n",
+ ptr, previous);
+ return 0;
+ }
+ if (next && !tiny_meta_header_is_free(next)) {
+ malloc_printf("*** invariant broken for %p (next in free list %p is not a free pointer)\n",
+ ptr, next);
+ return 0;
+ }
+ /*
+ * Check the free block's trailing size value.
+ */
+ follower = FOLLOWING_TINY_PTR(ptr, msize);
+ if (((uintptr_t)follower != region_end) && (get_tiny_previous_free_msize(follower) != msize)) {
+ malloc_printf("*** invariant broken for tiny free %p followed by %p in region [%p-%p] "
+ "(end marker incorrect) should be %d; in fact %d\n",
+ ptr, follower, TINY_REGION_ADDRESS(region), region_end, msize, get_tiny_previous_free_msize(follower));
+ return 0;
+ }
+ /* move to next block */
+ ptr = (uintptr_t)follower;
+ }
+ }
+ /*
+ * Ensure that we scanned the entire region
+ */
+ if (ptr != region_end) {
+ malloc_printf("*** invariant broken for region end %p - %p\n", ptr, region_end);
+ return 0;
+ }
+ /*
+ * Check the trailing block's integrity.
+ */
+ if (region == szone->last_tiny_region) {
+ if (szone->tiny_bytes_free_at_end) {
+ msize = get_tiny_meta_header((void *)ptr, &is_free);
+ if (is_free || (msize != 1)) {
+ malloc_printf("*** invariant broken for blocker block %p - %d %d\n", ptr, msize, is_free);
+ }
+ }
+ }
+ return 1;
+}
+
+static kern_return_t
+tiny_in_use_enumerator(task_t task, void *context, unsigned type_mask, szone_t *szone, memory_reader_t reader, vm_range_recorder_t recorder)
+{
+ size_t num_regions = szone->num_tiny_regions_allocated;
+ void *last_tiny_free = szone->last_tiny_free;
+ size_t index;
+ region_t *regions;
+ vm_range_t buffer[MAX_RECORDER_BUFFER];
+ unsigned count = 0;
+ kern_return_t err;
+ region_t region;
+ vm_range_t range;
+ vm_range_t admin_range;
+ vm_range_t ptr_range;
+ unsigned char *mapped_region;
+ unsigned char *block_header;
+ unsigned char *in_use;
+ unsigned block_index;
+ unsigned block_limit;
+ boolean_t is_free;
+ msize_t msize;
+ void *mapped_ptr;
+ unsigned bit;
+ vm_address_t last_tiny_free_ptr = 0;
+ msize_t last_tiny_free_msize = 0;
+
+ if (last_tiny_free) {
+ last_tiny_free_ptr = (uintptr_t) last_tiny_free & ~(TINY_QUANTUM - 1);
+ last_tiny_free_msize = (uintptr_t) last_tiny_free & (TINY_QUANTUM - 1);
+ }
+
+ err = reader(task, (vm_address_t)szone->tiny_regions, sizeof(region_t) * num_regions, (void **)®ions);
+ if (err) return err;
+ for (index = 0; index < num_regions; ++index) {
+ region = regions[index];
+ if (region) {
+ range.address = (vm_address_t)TINY_REGION_ADDRESS(region);
+ range.size = (vm_size_t)TINY_REGION_SIZE;
+ if (type_mask & MALLOC_ADMIN_REGION_RANGE_TYPE) {
+ admin_range.address = range.address + TINY_HEADER_START;
+ admin_range.size = TINY_HEADER_SIZE;
+ recorder(task, context, MALLOC_ADMIN_REGION_RANGE_TYPE, &admin_range, 1);
+ }
+ if (type_mask & (MALLOC_PTR_REGION_RANGE_TYPE | MALLOC_ADMIN_REGION_RANGE_TYPE)) {
+ ptr_range.address = range.address;
+ ptr_range.size = NUM_TINY_BLOCKS * TINY_QUANTUM;
+ recorder(task, context, MALLOC_PTR_REGION_RANGE_TYPE, &ptr_range, 1);
+ }
+ if (type_mask & MALLOC_PTR_IN_USE_RANGE_TYPE) {
+ err = reader(task, range.address, range.size, (void **)&mapped_region);
+ if (err)
+ return err;
+
+ block_header = (unsigned char *)(mapped_region + TINY_HEADER_START);
+ in_use = TINY_INUSE_FOR_HEADER(block_header);
+ block_index = 0;
+ block_limit = NUM_TINY_BLOCKS;
+ if (region == szone->last_tiny_region)
+ block_limit -= TINY_MSIZE_FOR_BYTES(szone->tiny_bytes_free_at_end);
+
+ while (block_index < block_limit) {
+ vm_size_t block_offset = TINY_BYTES_FOR_MSIZE(block_index);
+ is_free = !BITARRAY_BIT(in_use, block_index);
+ if (is_free) {
+ mapped_ptr = mapped_region + block_offset;
+
+ // mapped_region, the address at which 'range' in 'task' has been
+ // mapped into our process, is not necessarily aligned to
+ // TINY_BLOCKS_ALIGN.
+ //
+ // Since the code in get_tiny_free_size() assumes the pointer came
+ // from a properly aligned tiny region, and mapped_region is not
+ // necessarily aligned, then do the size calculation directly.
+ // If the next bit is set in the header bitmap, then the size is one
+ // quantum. Otherwise, read the size field.
+ if (!BITARRAY_BIT(block_header, block_index+1))
+ msize = TINY_FREE_SIZE(mapped_ptr);
+ else
+ msize = 1;
+
+ if (!msize)
+ break;
+ } else if (range.address + block_offset != last_tiny_free_ptr) {
+ msize = 1;
+ bit = block_index + 1;
+ while (! BITARRAY_BIT(block_header, bit)) {
+ bit++;
+ msize ++;
+ }
+ buffer[count].address = range.address + block_offset;
+ buffer[count].size = TINY_BYTES_FOR_MSIZE(msize);
+ count++;
+ if (count >= MAX_RECORDER_BUFFER) {
+ recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE, buffer, count);
+ count = 0;
+ }
+ } else {
+ // Block is not free but it matches last_tiny_free_ptr so even
+ // though it is not marked free in the bitmap, we treat it as if
+ // it is and move on
+ msize = last_tiny_free_msize;
+ }
+ block_index += msize;
+ }
+ }
+ }
+ }
+ if (count) {
+ recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE, buffer, count);
+ }
+ return 0;
+}
+
+static void *
+tiny_malloc_from_free_list(szone_t *szone, msize_t msize)
+{
+ // Assumes we've locked the region
+ free_list_t *ptr;
+ msize_t this_msize;
+ grain_t slot = msize - 1;
+ free_list_t **free_list = szone->tiny_free_list;
+ free_list_t **the_slot = free_list + slot;
+ free_list_t *next;
+ free_list_t **limit;
+ unsigned bitmap;
+ msize_t leftover_msize;
+ free_list_t *leftover_ptr;
+
+ // Assumes locked
+ CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
+
+ // Look for an exact match by checking the freelist for this msize.
+ //
+ ptr = *the_slot;
+ if (ptr) {
+ next = free_list_unchecksum_ptr(ptr->next);
+ if (next) {
+ next->previous = ptr->previous;
+ } else {
+ BITMAP32_CLR(szone->tiny_bitmap, slot);
+ }
+ *the_slot = next;
+ this_msize = msize;
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr)) {
+ malloc_printf("in tiny_malloc_from_free_list(), exact match ptr=%p, this_msize=%d\n", ptr, this_msize);
+ }
+#endif
+ goto return_tiny_alloc;
+ }
+
+ // Mask off the bits representing slots holding free blocks smaller than the
+ // size we need. If there are no larger free blocks, try allocating from
+ // the free space at the end of the tiny region.
+ bitmap = szone->tiny_bitmap & ~ ((1 << slot) - 1);
+ if (!bitmap)
+ goto try_tiny_malloc_from_end;
+
+ slot = BITMAP32_CTZ(bitmap);
+ limit = free_list + NUM_TINY_SLOTS - 1;
+ free_list += slot;
+
+ // Iterate over freelists looking for free blocks, starting at first list
+ // which is not empty, and contains blocks which are large enough to satisfy
+ // our request.
+ while (free_list < limit) {
+ ptr = *free_list;
+ if (ptr) {
+ next = free_list_unchecksum_ptr(ptr->next);
+ *free_list = next;
+ this_msize = get_tiny_free_size(ptr);
+ if (next) {
+ next->previous = ptr->previous;
+ } else {
+ BITMAP32_CLR(szone->tiny_bitmap, this_msize - 1);
+ }
+ goto add_leftover_and_proceed;
+ }
+ free_list++;
+ }
+
+ // We are now looking at the last slot, which contains blocks equal to, or
+ // due to coalescing of free blocks, larger than 31 * tiny quantum size.
+ // If the last freelist is not empty, and the head contains a block that is
+ // larger than our request, then the remainder is put back on the free list.
+ ptr = *limit;
+ if (ptr) {
+ free_list_checksum(szone, ptr, __PRETTY_FUNCTION__);
+ this_msize = get_tiny_free_size(ptr);
+ next = free_list_unchecksum_ptr(ptr->next);
+ if (this_msize - msize >= NUM_TINY_SLOTS) {
+ // the leftover will go back to the free list, so we optimize by
+ // modifying the free list rather than a pop and push of the head
+ leftover_msize = this_msize - msize;
+ leftover_ptr = (free_list_t *)((unsigned char *)ptr + TINY_BYTES_FOR_MSIZE(msize));
+ *limit = leftover_ptr;
+ if (next) {
+ next->previous.u = free_list_checksum_ptr(leftover_ptr);
+ }
+ leftover_ptr->previous = ptr->previous;
+ leftover_ptr->next = ptr->next;
+ set_tiny_meta_header_free(leftover_ptr, leftover_msize);
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in tiny_malloc_from_free_list(), last slot ptr=%p, msize=%d this_msize=%d\n", ptr, msize, this_msize);
+ }
+#endif
+ this_msize = msize;
+ goto return_tiny_alloc;
+ }
+ if (next) {
+ next->previous = ptr->previous;
+ }
+ *limit = next;
+ goto add_leftover_and_proceed;
+ }
+
+try_tiny_malloc_from_end:
+ // Let's see if we can use szone->tiny_bytes_free_at_end
+ if (szone->tiny_bytes_free_at_end >= TINY_BYTES_FOR_MSIZE(msize)) {
+ ptr = (free_list_t *)(TINY_REGION_END(szone->last_tiny_region) - szone->tiny_bytes_free_at_end);
+ szone->tiny_bytes_free_at_end -= TINY_BYTES_FOR_MSIZE(msize);
+ if (szone->tiny_bytes_free_at_end) {
+ // let's add an in use block after ptr to serve as boundary
+ set_tiny_meta_header_in_use((unsigned char *)ptr + TINY_BYTES_FOR_MSIZE(msize), 1);
+ }
+ this_msize = msize;
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr)) {
+ malloc_printf("in tiny_malloc_from_free_list(), from end ptr=%p, msize=%d\n", ptr, msize);
+ }
+#endif
+ goto return_tiny_alloc;
+ }
+ return NULL;
+
+add_leftover_and_proceed:
+ if (!this_msize || (this_msize > msize)) {
+ leftover_msize = this_msize - msize;
+ leftover_ptr = (free_list_t *)((unsigned char *)ptr + TINY_BYTES_FOR_MSIZE(msize));
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in tiny_malloc_from_free_list(), adding leftover ptr=%p, this_msize=%d\n", ptr, this_msize);
+ }
+#endif
+ tiny_free_list_add_ptr(szone, leftover_ptr, leftover_msize);
+ this_msize = msize;
+ }
+
+return_tiny_alloc:
+ szone->num_tiny_objects++;
+ szone->num_bytes_in_tiny_objects += TINY_BYTES_FOR_MSIZE(this_msize);
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in tiny_malloc_from_free_list(), ptr=%p, this_msize=%d, msize=%d\n", ptr, this_msize, msize);
+ }
+#endif
+ set_tiny_meta_header_in_use(ptr, this_msize);
+ return ptr;
+}
+
+static INLINE void *
+tiny_malloc_should_clear(szone_t *szone, msize_t msize, boolean_t cleared_requested)
+{
+ boolean_t locked = 0;
+ void *ptr;
+
+#if DEBUG_MALLOC
+ if (!msize) {
+ szone_error(szone, "invariant broken (!msize) in allocation (region)", NULL, NULL);
+ return(NULL);
+ }
+#endif
+#if TINY_CACHE
+ ptr = szone->last_tiny_free;
+ if ((((uintptr_t)ptr) & (TINY_QUANTUM - 1)) == msize) {
+ // we have a candidate - let's lock to make sure
+ LOCK_AND_NOTE_LOCKED(szone, locked);
+ if (ptr == szone->last_tiny_free) {
+ szone->last_tiny_free = NULL;
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ ptr = (void *)((uintptr_t)ptr & ~ (TINY_QUANTUM - 1));
+ if (cleared_requested) {
+ memset(ptr, 0, TINY_BYTES_FOR_MSIZE(msize));
+ }
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in tiny_malloc_should_clear(), tiny cache ptr=%p, msize=%d\n", ptr, msize);
+ }
+#endif
+ return ptr;
+ }
+ }
+#endif
+ // Except in rare occasions where we need to add a new region, we are going to end up locking, so we might as well lock right away to avoid doing unnecessary optimistic probes
+ if (!locked) LOCK_AND_NOTE_LOCKED(szone, locked);
+ ptr = tiny_malloc_from_free_list(szone, msize);
+ if (ptr) {
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ if (cleared_requested) {
+ memset(ptr, 0, TINY_BYTES_FOR_MSIZE(msize));
+ }
+ return ptr;
+ }
+ ptr = tiny_malloc_from_region_no_lock(szone, msize);
+ // we don't clear because this freshly allocated space is pristine
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ return ptr;
+}
+
+static INLINE void
+free_tiny(szone_t *szone, void *ptr, region_t *tiny_region)
+{
+ msize_t msize;
+ boolean_t is_free;
+#if TINY_CACHE
+ void *ptr2;
+#endif
+
+ // ptr is known to be in tiny_region
+ SZONE_LOCK(szone);
+#if TINY_CACHE
+ ptr2 = szone->last_tiny_free;
+ /* check that we don't already have this pointer in the cache */
+ if (ptr == (void *)((uintptr_t)ptr2 & ~ (TINY_QUANTUM - 1))) {
+ szone_error(szone, "double free", ptr, NULL);
+ return;
+ }
+#endif /* TINY_CACHE */
+ msize = get_tiny_meta_header(ptr, &is_free);
+ if (is_free) {
+ szone_error(szone, "double free", ptr, NULL);
+ return;
+ }
+#if DEBUG_MALLOC
+ if (!msize) {
+ malloc_printf("*** szone_free() block in use is too large: %p\n", ptr);
+ return;
+ }
+#endif
+#if TINY_CACHE
+ if (msize < TINY_QUANTUM) { // to see if the bits fit in the last 4 bits
+ if ((szone->debug_flags & SCALABLE_MALLOC_DO_SCRIBBLE) && msize)
+ memset(ptr, 0x55, TINY_BYTES_FOR_MSIZE(msize));
+ szone->last_tiny_free = (void *)(((uintptr_t)ptr) | msize);
+ if (!ptr2) {
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ return;
+ }
+ msize = (uintptr_t)ptr2 & (TINY_QUANTUM - 1);
+ ptr = (void *)(((uintptr_t)ptr2) & ~(TINY_QUANTUM - 1));
+ tiny_region = tiny_region_for_ptr_no_lock(szone, ptr);
+ if (!tiny_region) {
+ szone_error(szone, "double free (tiny cache)", ptr, NULL);
+ }
+ }
+#endif
+ tiny_free_no_lock(szone, tiny_region, ptr, msize);
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+}
+
+static void
+print_tiny_free_list(szone_t *szone)
+{
+ grain_t slot = 0;
+ free_list_t *ptr;
+ _SIMPLE_STRING b = _simple_salloc();
+
+ if (b) {
+ _simple_sappend(b, "tiny free sizes: ");
+ while (slot < NUM_TINY_SLOTS) {
+ ptr = szone->tiny_free_list[slot];
+ if (ptr) {
+ _simple_sprintf(b, "%s%y[%d]; ", (slot == NUM_TINY_SLOTS-1) ? ">=" : "", (slot+1)*TINY_QUANTUM, free_list_count(ptr));
+ }
+ slot++;
+ }
+ _malloc_printf(MALLOC_PRINTF_NOLOG | MALLOC_PRINTF_NOPREFIX, "%s\n", _simple_string(b));
+ _simple_sfree(b);
+ }
+}
+
+static void
+print_tiny_region(boolean_t verbose, region_t region, size_t bytes_at_end)
+{
+ unsigned counts[1024];
+ unsigned in_use = 0;
+ uintptr_t start = (uintptr_t)TINY_REGION_ADDRESS(region);
+ uintptr_t current = start;
+ uintptr_t limit = (uintptr_t)TINY_REGION_END(region) - bytes_at_end;
+ boolean_t is_free;
+ msize_t msize;
+ unsigned ci;
+ _SIMPLE_STRING b;
+
+ memset(counts, 0, 1024 * sizeof(unsigned));
+ while (current < limit) {
+ msize = get_tiny_meta_header((void *)current, &is_free);
+ if (is_free & !msize && (current == start)) {
+ // first block is all free
+ break;
+ }
+ if (!msize) {
+ malloc_printf("*** error with %p: msize=%d\n", (void *)current, (unsigned)msize);
+ break;
+ }
+ if (!is_free) {
+ // block in use
+ if (msize > 32)
+ malloc_printf("*** error at %p msize for in_use is %d\n", (void *)current, msize);
+ if (msize < 1024)
+ counts[msize]++;
+ in_use++;
+ }
+ current += TINY_BYTES_FOR_MSIZE(msize);
+ }
+ if ((b = _simple_salloc()) != NULL) {
+ _simple_sprintf(b, "Tiny region [%p-%p, %y]\t", (void *)start, TINY_REGION_END(region), (int)TINY_REGION_SIZE);
+ _simple_sprintf(b, "In_use=%d ", in_use);
+ if (bytes_at_end) _simple_sprintf(b, "untouched=%ly", bytes_at_end);
+ if (verbose && in_use) {
+ _simple_sappend(b, "\n\tSizes in use: ");
+ for (ci = 0; ci < 1024; ci++)
+ if (counts[ci])
+ _simple_sprintf(b, "%d[%d]", TINY_BYTES_FOR_MSIZE(ci), counts[ci]);
+ }
+ _malloc_printf(MALLOC_PRINTF_NOLOG | MALLOC_PRINTF_NOPREFIX, "%s\n", _simple_string(b));
+ _simple_sfree(b);
+ }
+}
+
+static boolean_t
+tiny_free_list_check(szone_t *szone, grain_t slot)
+{
+ unsigned count = 0;
+ free_list_t *ptr = szone->tiny_free_list[slot];
+ free_list_t *previous = NULL;
+ boolean_t is_free;
+
+ CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
+ while (ptr) {
+ free_list_checksum(szone, ptr, __PRETTY_FUNCTION__);
+ is_free = tiny_meta_header_is_free(ptr);
+ if (! is_free) {
+ malloc_printf("*** in-use ptr in free list slot=%d count=%d ptr=%p\n", slot, count, ptr);
+ return 0;
+ }
+ if (((uintptr_t)ptr) & (TINY_QUANTUM - 1)) {
+ malloc_printf("*** unaligned ptr in free list slot=%d count=%d ptr=%p\n", slot, count, ptr);
+ return 0;
+ }
+ if (!tiny_region_for_ptr_no_lock(szone, ptr)) {
+ malloc_printf("*** ptr not in szone slot=%d count=%d ptr=%p\n", slot, count, ptr);
+ return 0;
+ }
+ if (free_list_unchecksum_ptr(ptr->previous) != previous) {
+ malloc_printf("*** previous incorrectly set slot=%d count=%d ptr=%p\n", slot, count, ptr);
+ return 0;
+ }
+ previous = ptr;
+ ptr = free_list_unchecksum_ptr(ptr->next);
+ count++;
+ }
+ return 1;
+}
+
+/********************* SMALL FREE LIST UTILITIES ************************/
+
+/*
+ * Mark a block as free. Only the first quantum of a block is marked thusly,
+ * the remainder are marked "middle".
+ */
+static INLINE void
+small_meta_header_set_is_free(msize_t *meta_headers, unsigned index, msize_t msize)
+{
+ meta_headers[index] = msize | SMALL_IS_FREE;
+}
+
+/*
+ * Mark a block as in use. Only the first quantum of a block is marked thusly,
+ * the remainder are marked "middle".
+ */
+static INLINE void
+small_meta_header_set_in_use(msize_t *meta_headers, msize_t index, msize_t msize)
+{
+ meta_headers[index] = msize;
+}
+
+/*
+ * Mark a quantum as being the second or later in a block.
+ */
+static INLINE void
+small_meta_header_set_middle(msize_t *meta_headers, msize_t index)
+{
+ meta_headers[index] = 0;
+}
+
+// Adds an item to the proper free list
+// Also marks the header of the block properly
+// Assumes szone has been locked
+static void
+small_free_list_add_ptr(szone_t *szone, void *ptr, msize_t msize)
+{
+ grain_t slot = (msize <= NUM_SMALL_SLOTS) ? msize - 1 : NUM_SMALL_SLOTS - 1;
+ free_list_t *free_ptr = ptr;
+ free_list_t *free_head = szone->small_free_list[slot];
+ void *follower;
+
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in %s, ptr=%p, msize=%d\n", __FUNCTION__, ptr, msize);
+ }
+ if (((uintptr_t)ptr) & (SMALL_QUANTUM - 1)) {
+ szone_error(szone, "small_free_list_add_ptr: Unaligned ptr", ptr, NULL);
+ }
+#endif
+ if (free_head) {
+ free_list_checksum(szone, free_head, __PRETTY_FUNCTION__);
+#if DEBUG_MALLOC
+ if (free_list_unchecksum_ptr(free_head->previous)) {
+ szone_error(szone, "small_free_list_add_ptr: Internal invariant broken (free_head->previous)", ptr,
+ "ptr=%p slot=%d free_head=%p previous=%p\n", ptr, slot, free_head, free_head->previous.p);
+ }
+ if (!SMALL_PTR_IS_FREE(free_head)) {
+ szone_error(szone, "small_free_list_add_ptr: Internal invariant broken (free_head is not a free pointer)", ptr,
+ "ptr=%p slot=%d free_head=%p\n", ptr, slot, free_head);
+ }
+#endif
+ free_head->previous.u = free_list_checksum_ptr(free_ptr);
+ } else {
+ BITMAP32_SET(szone->small_bitmap, slot);
+ }
+ free_ptr->previous.p = NULL;
+ free_ptr->next.p = free_head;
+ free_list_set_checksum(szone, free_ptr);
+ szone->small_free_list[slot] = free_ptr;
+ follower = ptr + SMALL_BYTES_FOR_MSIZE(msize);
+ SMALL_PREVIOUS_MSIZE(follower) = msize;
+}
+
+// Removes item in the proper free list
+// msize could be read, but all callers have it so we pass it in
+// Assumes szone has been locked
+static void
+small_free_list_remove_ptr(szone_t *szone, void *ptr, msize_t msize)
+{
+ grain_t slot = (msize <= NUM_SMALL_SLOTS) ? msize - 1 : NUM_SMALL_SLOTS - 1;
+ free_list_t *free_ptr = ptr, *next, *previous;
+ free_list_checksum(szone, free_ptr, __PRETTY_FUNCTION__);
+
+ next = free_list_unchecksum_ptr(free_ptr->next);
+ previous = free_list_unchecksum_ptr(free_ptr->previous);
+
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("In %s, ptr=%p, msize=%d\n", __FUNCTION__, ptr, msize);
+ }
+#endif
+ if (!previous) {
+ // The block to remove is the head of the free list
+#if DEBUG_MALLOC
+ if (szone->small_free_list[slot] != ptr) {
+ szone_error(szone, "small_free_list_remove_ptr: Internal invariant broken (szone->small_free_list[grain])", ptr,
+ "ptr=%p slot=%d msize=%d szone->small_free_list[slot]=%p\n",
+ ptr, slot, msize, szone->small_free_list[slot]);
+ return;
+ }
+#endif
+ szone->small_free_list[slot] = next;
+ if (!next) BITMAP32_CLR(szone->small_bitmap, slot);
+ } else {
+ // We know free_ptr is already checksummed, so we don't need to do it
+ // again.
+ previous->next = free_ptr->next;
+ }
+ if (next) {
+ // We know free_ptr is already checksummed, so we don't need to do it
+ // again.
+ next->previous = free_ptr->previous;
+ }
+}
+
+static INLINE region_t *
+small_region_for_ptr_no_lock(szone_t *szone, const void *ptr)
+{
+ return hash_lookup_region_no_lock(szone->small_regions,
+ szone->num_small_regions_allocated,
+ SMALL_REGION_FOR_PTR(ptr));
+}
+
+static INLINE void
+small_free_no_lock(szone_t *szone, region_t *region, void *ptr, msize_t msize)
+{
+ msize_t *meta_headers = SMALL_META_HEADER_FOR_PTR(ptr);
+ unsigned index = SMALL_META_INDEX_FOR_PTR(ptr);
+ size_t original_size = SMALL_BYTES_FOR_MSIZE(msize);
+ unsigned char *next_block = ((unsigned char *)ptr + original_size);
+ msize_t next_index = index + msize;
+ msize_t previous_msize, next_msize;
+ void *previous;
+
+ // Assumes locked
+ CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in small_free_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
+ }
+ if (! msize) {
+ szone_error(szone, "trying to free small block that is too small", ptr,
+ "in small_free_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
+ }
+#endif
+ // We try to coalesce this block with the preceeding one
+ if (index && (SMALL_PREVIOUS_MSIZE(ptr) <= index)) {
+ previous_msize = SMALL_PREVIOUS_MSIZE(ptr);
+ if (meta_headers[index - previous_msize] == (previous_msize | SMALL_IS_FREE)) {
+ previous = ptr - SMALL_BYTES_FOR_MSIZE(previous_msize);
+ // previous is really to be coalesced
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr) || LOG(szone,previous)) {
+ malloc_printf("in small_free_no_lock(), coalesced backwards for %p previous=%p\n", ptr, previous);
+ }
+#endif
+ small_free_list_remove_ptr(szone, previous, previous_msize);
+ small_meta_header_set_middle(meta_headers, index);
+ ptr = previous;
+ msize += previous_msize;
+ index -= previous_msize;
+ }
+ }
+ // We try to coalesce with the next block
+ if ((next_block < SMALL_REGION_END(*region)) && (meta_headers[next_index] & SMALL_IS_FREE)) {
+ // next block is free, we coalesce
+ next_msize = meta_headers[next_index] & ~ SMALL_IS_FREE;
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) malloc_printf("In small_free_no_lock(), for ptr=%p, msize=%d coalesced next block=%p next_msize=%d\n", ptr, msize, next_block, next_msize);
+#endif
+ small_free_list_remove_ptr(szone, next_block, next_msize);
+ small_meta_header_set_middle(meta_headers, next_index);
+ msize += next_msize;
+ }
+ if (szone->debug_flags & SCALABLE_MALLOC_DO_SCRIBBLE) {
+ if (!msize) {
+ szone_error(szone, "incorrect size information - block header was damaged", ptr, NULL);
+ } else {
+ memset(ptr, 0x55, SMALL_BYTES_FOR_MSIZE(msize));
+ }
+ }
+ small_free_list_add_ptr(szone, ptr, msize);
+ small_meta_header_set_is_free(meta_headers, index, msize);
+ szone->num_small_objects--;
+ szone->num_bytes_in_small_objects -= original_size; // we use original_size and not msize to avoid double counting the coalesced blocks
+}
+
+static void *
+small_malloc_from_region_no_lock(szone_t *szone, msize_t msize)
+{
+ void *last_block;
+ void *ptr;
+ void *new_address;
+ msize_t *meta_headers;
+ msize_t index ;
+ msize_t msize_left;
+
+ // Allocates from the last region or a freshly allocated region
+ CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
+ // Before anything we transform the small_bytes_free_at_end - if any - to a regular free block
+ if (szone->small_bytes_free_at_end) {
+ last_block = (void *)(SMALL_REGION_END(szone->last_small_region) - szone->small_bytes_free_at_end);
+ small_free_list_add_ptr(szone, last_block, SMALL_MSIZE_FOR_BYTES(szone->small_bytes_free_at_end));
+ *SMALL_METADATA_FOR_PTR(last_block) = SMALL_MSIZE_FOR_BYTES(szone->small_bytes_free_at_end) | SMALL_IS_FREE;
+ szone->small_bytes_free_at_end = 0;
+ }
+ // time to create a new region
+ new_address = allocate_pages(szone, SMALL_REGION_SIZE, SMALL_BLOCKS_ALIGN,
+ 0, VM_MEMORY_MALLOC_SMALL);
+ if (!new_address)
+ return NULL;
+
+ ptr = new_address;
+ meta_headers = SMALL_META_HEADER_FOR_PTR(ptr);
+ index = 0;
+
+ // Check to see if the hash ring of small regions needs to grow. Try to
+ // avoid the hash ring becoming too dense.
+ if (szone->num_small_regions_allocated < (2 * szone->num_small_regions)) {
+ region_t *new_regions;
+ size_t new_size;
+ new_regions = hash_regions_grow_no_lock(szone, szone->small_regions,
+ szone->num_small_regions_allocated,
+ &new_size);
+ // Do not deallocate the current small_regions allocation since someone
+ // may be iterating it. Instead, just leak it.
+ szone->small_regions = new_regions;
+ szone->num_small_regions_allocated = new_size;
+ }
+ // Insert the new region into the hash ring, and update malloc statistics
+ hash_region_insert_no_lock(szone->small_regions,
+ szone->num_small_regions_allocated,
+ new_address);
+ szone->last_small_region = new_address;
+
+ // we bump the number of regions AFTER we have changes the regions pointer
+ // to enable finding a small region without taking the lock
+ //
+ // FIXME: naive assumption assumes memory ordering coherence between this
+ // and other CPUs. This also applies to the near-identical code in
+ // tiny_malloc_from_region_no_lock.
+ szone->num_small_regions++;
+ small_meta_header_set_in_use(meta_headers, index, msize);
+ msize_left = NUM_SMALL_BLOCKS - index;
+ szone->num_small_objects++;
+ szone->num_bytes_in_small_objects += SMALL_BYTES_FOR_MSIZE(msize);
+ // add a big free block
+ index += msize; msize_left -= msize;
+ meta_headers[index] = msize_left;
+ szone->small_bytes_free_at_end = SMALL_BYTES_FOR_MSIZE(msize_left);
+ return ptr;
+}
+
+static INLINE boolean_t
+try_realloc_small_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size)
+{
+ // returns 1 on success
+ msize_t *meta_headers = SMALL_META_HEADER_FOR_PTR(ptr);
+ unsigned index = SMALL_META_INDEX_FOR_PTR(ptr);
+ msize_t old_msize = SMALL_MSIZE_FOR_BYTES(old_size);
+ msize_t new_msize = SMALL_MSIZE_FOR_BYTES(new_size + SMALL_QUANTUM - 1);
+ void *next_block = (char *)ptr + old_size;
+ unsigned next_index = index + old_msize;
+ msize_t next_msize_and_free;
+ msize_t next_msize;
+ msize_t leftover_msize;
+ void *leftover;
+ unsigned leftover_index;
+
+ if (next_index >= NUM_SMALL_BLOCKS) {
+ return 0;
+ }
+#if DEBUG_MALLOC
+ if ((uintptr_t)next_block & (SMALL_QUANTUM - 1)) {
+ szone_error(szone, "internal invariant broken in realloc(next_block)", next_block, NULL);
+ }
+ if (meta_headers[index] != old_msize)
+ malloc_printf("*** try_realloc_small_in_place incorrect old %d %d\n",
+ meta_headers[index], old_msize);
+#endif
+ SZONE_LOCK(szone);
+ /*
+ * Look for a free block immediately afterwards. If it's large enough, we can consume (part of)
+ * it.
+ */
+ next_msize_and_free = meta_headers[next_index];
+ next_msize = next_msize_and_free & ~ SMALL_IS_FREE;
+ if (!(next_msize_and_free & SMALL_IS_FREE) || (old_msize + next_msize < new_msize)) {
+ SZONE_UNLOCK(szone);
+ return 0;
+ }
+ /*
+ * The following block is big enough; pull it from its freelist and chop off enough to satisfy
+ * our needs.
+ */
+ small_free_list_remove_ptr(szone, next_block, next_msize);
+ small_meta_header_set_middle(meta_headers, next_index);
+ leftover_msize = old_msize + next_msize - new_msize;
+ if (leftover_msize) {
+ /* there's some left, so put the remainder back */
+ leftover = (unsigned char *)ptr + SMALL_BYTES_FOR_MSIZE(new_msize);
+ small_free_list_add_ptr(szone, leftover, leftover_msize);
+ leftover_index = index + new_msize;
+ small_meta_header_set_is_free(meta_headers, leftover_index, leftover_msize);
+ }
+#if DEBUG_MALLOC
+ if (SMALL_BYTES_FOR_MSIZE(new_msize) >= LARGE_THRESHOLD) {
+ malloc_printf("*** realloc in place for %p exceeded msize=%d\n", new_msize);
+ }
+#endif
+ small_meta_header_set_in_use(meta_headers, index, new_msize);
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in szone_realloc(), ptr=%p, msize=%d\n", ptr, *SMALL_METADATA_FOR_PTR(ptr));
+ }
+#endif
+ szone->num_bytes_in_small_objects += SMALL_BYTES_FOR_MSIZE(new_msize - old_msize);
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ return 1;
+}
+
+static boolean_t
+szone_check_small_region(szone_t *szone, region_t region)
+{
+ unsigned char *ptr = SMALL_REGION_ADDRESS(region);
+ msize_t *meta_headers = SMALL_META_HEADER_FOR_PTR(ptr);
+ unsigned char *region_end = SMALL_REGION_END(region);
+ msize_t prev_free = 0;
+ unsigned index;
+ msize_t msize_and_free;
+ msize_t msize;
+ free_list_t *free_head;
+ void *previous, *next;
+ msize_t *follower;
+
+ CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
+ if (region == szone->last_small_region) region_end -= szone->small_bytes_free_at_end;
+ while (ptr < region_end) {
+ index = SMALL_META_INDEX_FOR_PTR(ptr);
+ msize_and_free = meta_headers[index];
+ if (!(msize_and_free & SMALL_IS_FREE)) {
+ // block is in use
+ msize = msize_and_free;
+ if (!msize) {
+ malloc_printf("*** invariant broken: null msize ptr=%p num_small_regions=%d end=%p\n",
+ ptr, szone->num_small_regions, region_end);
+ return 0;
+ }
+ if (msize > (LARGE_THRESHOLD / SMALL_QUANTUM)) {
+ malloc_printf("*** invariant broken for %p this small msize=%d - size is too large\n",
+ ptr, msize_and_free);
+ return 0;
+ }
+ ptr += SMALL_BYTES_FOR_MSIZE(msize);
+ prev_free = 0;
+ } else {
+ // free pointer
+ msize = msize_and_free & ~ SMALL_IS_FREE;
+ free_head = (free_list_t *)ptr;
+ follower = (msize_t *)FOLLOWING_SMALL_PTR(ptr, msize);
+ if (!msize) {
+ malloc_printf("*** invariant broken for free block %p this msize=%d\n", ptr, msize);
+ return 0;
+ }
+ if (prev_free) {
+ malloc_printf("*** invariant broken for %p (2 free in a row)\n", ptr);
+ return 0;
+ }
+ free_list_checksum(szone, free_head, __PRETTY_FUNCTION__);
+ previous = free_list_unchecksum_ptr(free_head->previous);
+ next = free_list_unchecksum_ptr(free_head->next);
+ if (previous && !SMALL_PTR_IS_FREE(previous)) {
+ malloc_printf("*** invariant broken for %p (previous %p is not a free pointer)\n",
+ ptr, free_head->previous);
+ return 0;
+ }
+ if (next && !SMALL_PTR_IS_FREE(next)) {
+ malloc_printf("*** invariant broken for %p (next is not a free pointer)\n", ptr);
+ return 0;
+ }
+ if (SMALL_PREVIOUS_MSIZE(follower) != msize) {
+ malloc_printf("*** invariant broken for small free %p followed by %p in region [%p-%p] "
+ "(end marker incorrect) should be %d; in fact %d\n",
+ ptr, follower, SMALL_REGION_ADDRESS(region), region_end, msize, SMALL_PREVIOUS_MSIZE(follower));
+ return 0;
+ }
+ ptr = (unsigned char *)follower;
+ prev_free = SMALL_IS_FREE;
+ }
+ }
+ return 1;
+}
+
+static kern_return_t
+small_in_use_enumerator(task_t task, void *context, unsigned type_mask, szone_t *szone, memory_reader_t reader, vm_range_recorder_t recorder)
+{
+ size_t num_regions = szone->num_small_regions_allocated;
+ void *last_small_free = szone->last_small_free;
+ size_t index;
+ region_t *regions;
+ vm_range_t buffer[MAX_RECORDER_BUFFER];
+ unsigned count = 0;
+ kern_return_t err;
+ region_t region;
+ vm_range_t range;
+ vm_range_t admin_range;
+ vm_range_t ptr_range;
+ unsigned char *mapped_region;
+ msize_t *block_header;
+ unsigned block_index;
+ unsigned block_limit;
+ msize_t msize_and_free;
+ msize_t msize;
+ vm_address_t last_small_free_ptr = 0;
+ msize_t last_small_free_msize = 0;
+
+ if (last_small_free) {
+ last_small_free_ptr = (uintptr_t)last_small_free & ~(SMALL_QUANTUM - 1);
+ last_small_free_msize = (uintptr_t)last_small_free & (SMALL_QUANTUM - 1);
+ }
+
+ err = reader(task, (vm_address_t)szone->small_regions, sizeof(region_t) * num_regions, (void **)®ions);
+ if (err) return err;
+ for (index = 0; index < num_regions; ++index) {
+ region = regions[index];
+ if (region) {
+ range.address = (vm_address_t)SMALL_REGION_ADDRESS(region);
+ range.size = SMALL_REGION_SIZE;
+ if (type_mask & MALLOC_ADMIN_REGION_RANGE_TYPE) {
+ admin_range.address = range.address + SMALL_HEADER_START;
+ admin_range.size = SMALL_ARRAY_SIZE;
+ recorder(task, context, MALLOC_ADMIN_REGION_RANGE_TYPE, &admin_range, 1);
+ }
+ if (type_mask & (MALLOC_PTR_REGION_RANGE_TYPE | MALLOC_ADMIN_REGION_RANGE_TYPE)) {
+ ptr_range.address = range.address;
+ ptr_range.size = NUM_SMALL_BLOCKS * SMALL_QUANTUM;
+ recorder(task, context, MALLOC_PTR_REGION_RANGE_TYPE, &ptr_range, 1);
+ }
+ if (type_mask & MALLOC_PTR_IN_USE_RANGE_TYPE) {
+ err = reader(task, range.address, range.size, (void **)&mapped_region);
+ if (err) return err;
+ block_header = (msize_t *)(mapped_region + SMALL_HEADER_START);
+ block_index = 0;
+ block_limit = NUM_SMALL_BLOCKS;
+ if (region == szone->last_small_region)
+ block_limit -= SMALL_MSIZE_FOR_BYTES(szone->small_bytes_free_at_end);
+ while (block_index < block_limit) {
+ msize_and_free = block_header[block_index];
+ msize = msize_and_free & ~ SMALL_IS_FREE;
+ if (! (msize_and_free & SMALL_IS_FREE) &&
+ range.address + SMALL_BYTES_FOR_MSIZE(block_index) != last_small_free_ptr) {
+ // Block in use
+ buffer[count].address = range.address + SMALL_BYTES_FOR_MSIZE(block_index);
+ buffer[count].size = SMALL_BYTES_FOR_MSIZE(msize);
+ count++;
+ if (count >= MAX_RECORDER_BUFFER) {
+ recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE, buffer, count);
+ count = 0;
+ }
+ }
+ block_index += msize;
+ }
+ }
+ }
+ }
+ if (count) {
+ recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE, buffer, count);
+ }
+ return 0;
+}
+
+static void *
+small_malloc_from_free_list(szone_t *szone, msize_t msize)
+{
+ free_list_t *ptr;
+ msize_t this_msize;
+ grain_t slot = (msize <= NUM_SMALL_SLOTS) ? msize - 1 : NUM_SMALL_SLOTS - 1;
+ free_list_t **free_list = szone->small_free_list;
+ free_list_t *next;
+ free_list_t **limit;
+ unsigned bitmap = szone->small_bitmap & ~ ((1 << slot) - 1);
+ msize_t leftover_msize;
+ free_list_t *leftover_ptr;
+ msize_t *meta_headers;
+ unsigned leftover_index;
+
+ // Assumes locked
+ CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
+
+ // Mask off the bits representing slots holding free blocks smaller than the
+ // size we need. If there are no larger free blocks, try allocating from
+ // the free space at the end of the tiny region.
+ if (!bitmap)
+ goto try_small_from_end;
+
+ slot = BITMAP32_CTZ(bitmap);
+ limit = free_list + NUM_SMALL_SLOTS - 1;
+ free_list += slot;
+
+ // Iterate over freelists looking for free blocks, starting at first list
+ // which is not empty, and contains blocks which are large enough to satisfy
+ // our request.
+ while (free_list < limit) {
+ ptr = *free_list;
+ if (ptr) {
+ next = free_list_unchecksum_ptr(ptr->next);
+ *free_list = next;
+ this_msize = SMALL_PTR_SIZE(ptr);
+ if (next) {
+ next->previous = ptr->previous;
+ } else {
+ BITMAP32_CLR(szone->small_bitmap, this_msize - 1);
+ }
+ goto add_leftover_and_proceed;
+ }
+ free_list++;
+ }
+
+ // We are now looking at the last slot, which contains blocks equal to, or
+ // due to coalescing of free blocks, larger than 31 * small quantum size.
+ // If the last freelist is not empty, and the head contains a block that is
+ // larger than our request, then the remainder is put back on the free list.
+ //
+ // FIXME: This code doesn't have the optimization from the 'tiny' codepath
+ // that optimizes for the this_msize >= 2 * num slots
+ // FIXME: this code also seems somewhat bogus. There's a check for
+ // this_msize >= msize, but by definition we can't ask for a small
+ // block larger than 31 small quanta, and every free block in this
+ // slot has to be at least that large.
+ ptr = *limit;
+ while (ptr) {
+ free_list_checksum(szone, ptr, __PRETTY_FUNCTION__);
+ next = free_list_unchecksum_ptr(ptr->next);
+ this_msize = SMALL_PTR_SIZE(ptr);
+ if (this_msize >= msize) {
+ small_free_list_remove_ptr(szone, ptr, this_msize);
+ goto add_leftover_and_proceed;
+ }
+ ptr = next;
+ }
+
+try_small_from_end:
+ // Let's see if we can use szone->small_bytes_free_at_end
+ if (szone->small_bytes_free_at_end >= SMALL_BYTES_FOR_MSIZE(msize)) {
+ ptr = (free_list_t *)(SMALL_REGION_END(szone->last_small_region) - szone->small_bytes_free_at_end);
+ szone->small_bytes_free_at_end -= SMALL_BYTES_FOR_MSIZE(msize);
+ if (szone->small_bytes_free_at_end) {
+ // let's mark this block as in use to serve as boundary
+ *SMALL_METADATA_FOR_PTR((unsigned char *)ptr + SMALL_BYTES_FOR_MSIZE(msize)) = SMALL_MSIZE_FOR_BYTES(szone->small_bytes_free_at_end);
+ }
+ this_msize = msize;
+ goto return_small_alloc;
+ }
+ return NULL;
+
+add_leftover_and_proceed:
+ if (this_msize > msize) {
+ leftover_msize = this_msize - msize;
+ leftover_ptr = (free_list_t *)((unsigned char *)ptr + SMALL_BYTES_FOR_MSIZE(msize));
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in small_malloc_from_free_list(), adding leftover ptr=%p, this_msize=%d\n", ptr, this_msize);
+ }
+#endif
+ small_free_list_add_ptr(szone, leftover_ptr, leftover_msize);
+ meta_headers = SMALL_META_HEADER_FOR_PTR(leftover_ptr);
+ leftover_index = SMALL_META_INDEX_FOR_PTR(leftover_ptr);
+ small_meta_header_set_is_free(meta_headers, leftover_index, leftover_msize);
+ this_msize = msize;
+ }
+
+return_small_alloc:
+ szone->num_small_objects++;
+ szone->num_bytes_in_small_objects += SMALL_BYTES_FOR_MSIZE(this_msize);
+#if DEBUG_MALLOC
+ if (LOG(szone,ptr)) {
+ malloc_printf("in small_malloc_from_free_list(), ptr=%p, this_msize=%d, msize=%d\n", ptr, this_msize, msize);
+ }
+#endif
+ *SMALL_METADATA_FOR_PTR(ptr) = this_msize;
+ return ptr;
+}
+
+static INLINE void *
+small_malloc_should_clear(szone_t *szone, msize_t msize, boolean_t cleared_requested)
+{
+ boolean_t locked = 0;
+#if SMALL_CACHE
+ void *ptr;
+#endif
+
+#if SMALL_CACHE
+ ptr = (void *)szone->last_small_free;
+ if ((((uintptr_t)ptr) & (SMALL_QUANTUM - 1)) == msize) {
+ // we have a candidate - let's lock to make sure
+ LOCK_AND_NOTE_LOCKED(szone, locked);
+ if (ptr == (void *)szone->last_small_free) {
+ szone->last_small_free = NULL;
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ ptr = (void *)((uintptr_t)ptr & ~ (SMALL_QUANTUM - 1));
+ if (cleared_requested) {
+ memset(ptr, 0, SMALL_BYTES_FOR_MSIZE(msize));
+ }
+ return ptr;
+ }
+ }
+#endif
+ // Except in rare occasions where we need to add a new region, we are going to end up locking,
+ // so we might as well lock right away to avoid doing unnecessary optimistic probes
+ if (!locked) LOCK_AND_NOTE_LOCKED(szone, locked);
+ ptr = small_malloc_from_free_list(szone, msize);
+ if (ptr) {
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ if (cleared_requested) {
+ memset(ptr, 0, SMALL_BYTES_FOR_MSIZE(msize));
+ }
+ return ptr;
+ }
+ ptr = small_malloc_from_region_no_lock(szone, msize);
+ // we don't clear because this freshly allocated space is pristine
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ return ptr;
+}
+
+// tries to allocate a small, cleared block
+static INLINE void *
+small_malloc_cleared_no_lock(szone_t *szone, msize_t msize)
+{
+ void *ptr;
+
+ // Assumes already locked
+ CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
+ ptr = small_malloc_from_free_list(szone, msize);
+ if (ptr) {
+ memset(ptr, 0, SMALL_BYTES_FOR_MSIZE(msize));
+ return ptr;
+ } else {
+ ptr = small_malloc_from_region_no_lock(szone, msize);
+ // we don't clear because this freshly allocated space is pristine
+ }
+ return ptr;
+}
+
+static INLINE void
+free_small(szone_t *szone, void *ptr, region_t *small_region)
+{
+ msize_t msize = SMALL_PTR_SIZE(ptr);
+#if SMALL_CACHE
+ void *ptr2;
+#endif
+
+ // ptr is known to be in small_region
+ SZONE_LOCK(szone);
+#if SMALL_CACHE
+ ptr2 = szone->last_small_free;
+ /* check that we don't already have this pointer in the cache */
+ if (ptr == (void *)((uintptr_t)ptr2 & ~ (SMALL_QUANTUM - 1))) {
+ szone_error(szone, "double free", ptr, NULL);
+ return;
+ }
+#endif
+ if (SMALL_PTR_IS_FREE(ptr)) {
+ szone_error(szone, "double free", ptr, NULL);
+ return;
+ }
+#if SMALL_CACHE
+ szone->last_small_free = (void *)(((uintptr_t)ptr) | msize);
+ if (!ptr2) {
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ return;
+ }
+ msize = (uintptr_t)ptr2 & (SMALL_QUANTUM - 1);
+ ptr = (void *)(((uintptr_t)ptr2) & ~ (SMALL_QUANTUM - 1));
+ small_region = small_region_for_ptr_no_lock(szone, ptr);
+ if (!small_region) {
+ szone_error(szone, "double free (small cache)", ptr, NULL);
+ return;
+ }
+#endif
+ small_free_no_lock(szone, small_region, ptr, msize);
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+}
+
+static void
+print_small_free_list(szone_t *szone)
+{
+ grain_t grain = 0;
+ free_list_t *ptr;
+ _SIMPLE_STRING b = _simple_salloc();
+
+ if (b) {
+ _simple_sappend(b, "small free sizes: ");
+ while (grain < NUM_SMALL_SLOTS) {
+ ptr = szone->small_free_list[grain];
+ if (ptr) {
+ _simple_sprintf(b, "%s%y[%d]; ", (grain == NUM_SMALL_SLOTS-1) ? ">=" : "", (grain + 1) * SMALL_QUANTUM, free_list_count(ptr));
+ }
+ grain++;
+ }
+ _malloc_printf(MALLOC_PRINTF_NOLOG | MALLOC_PRINTF_NOPREFIX, "%s\n", _simple_string(b));
+ _simple_sfree(b);
+ }
+}
+
+static void
+print_small_region(szone_t *szone, boolean_t verbose, region_t region, size_t bytes_at_end)
+{
+ unsigned counts[1024];
+ unsigned in_use = 0;
+ void *start = SMALL_REGION_ADDRESS(region);
+ void *limit = SMALL_REGION_END(region) - bytes_at_end;
+ msize_t msize_and_free;
+ msize_t msize;
+ unsigned ci;
+ _SIMPLE_STRING b;
+
+ memset(counts, 0, 1024 * sizeof(unsigned));
+ while (start < limit) {
+ msize_and_free = *SMALL_METADATA_FOR_PTR(start);
+ msize = msize_and_free & ~ SMALL_IS_FREE;
+ if (!(msize_and_free & SMALL_IS_FREE)) {
+ // block in use
+ if (msize < 1024)
+ counts[msize]++;
+ in_use++;
+ }
+ start += SMALL_BYTES_FOR_MSIZE(msize);
+ }
+ if ((b = _simple_salloc()) != NULL) {
+ _simple_sprintf(b, "Small region [%p-%p, %y]\tIn_use=%d ",
+ SMALL_REGION_ADDRESS(region), SMALL_REGION_END(region), (int)SMALL_REGION_SIZE, in_use);
+ if (bytes_at_end)
+ _simple_sprintf(b, "Untouched=%ly", bytes_at_end);
+ if (verbose && in_use) {
+ _simple_sappend(b, "\n\tSizes in use: ");
+ for (ci = 0; ci < 1024; ci++)
+ if (counts[ci])
+ _simple_sprintf(b, "%d[%d] ", SMALL_BYTES_FOR_MSIZE(ci), counts[ci]);
+ }
+ _malloc_printf(MALLOC_PRINTF_NOLOG | MALLOC_PRINTF_NOPREFIX, "%s\n", _simple_string(b));
+ _simple_sfree(b);
+ }
+}
+
+static boolean_t
+small_free_list_check(szone_t *szone, grain_t grain)
+{
+ unsigned count = 0;
+ free_list_t *ptr = szone->small_free_list[grain];
+ free_list_t *previous = NULL;
+ msize_t msize_and_free;
+
+ CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
+ while (ptr) {
+ msize_and_free = *SMALL_METADATA_FOR_PTR(ptr);
+ count++;
+ if (!(msize_and_free & SMALL_IS_FREE)) {
+ malloc_printf("*** in-use ptr in free list grain=%d count=%d ptr=%p\n", grain, count, ptr);
+ return 0;
+ }
+ if (((uintptr_t)ptr) & (SMALL_QUANTUM - 1)) {
+ malloc_printf("*** unaligned ptr in free list grain=%d count=%d ptr=%p\n", grain, count, ptr);
+ return 0;
+ }
+ if (!small_region_for_ptr_no_lock(szone, ptr)) {
+ malloc_printf("*** ptr not in szone grain=%d count=%d ptr=%p\n", grain, count, ptr);
+ return 0;
+ }
+ free_list_checksum(szone, ptr, __PRETTY_FUNCTION__);
+ if (free_list_unchecksum_ptr(ptr->previous) != previous) {
+ malloc_printf("*** previous incorrectly set grain=%d count=%d ptr=%p\n", grain, count, ptr);
+ return 0;
+ }
+ previous = ptr;
+ ptr = free_list_unchecksum_ptr(ptr->next);
+ }
+ return 1;
+}
+
+/*******************************************************************************
+ * Region hash implementation
+ *
+ * This is essentially a duplicate of the existing Large allocator hash, minus
+ * the ability to remove entries. The two should be combined eventually.
+ ******************************************************************************/
+#pragma mark region hash
+
+/*
+ * hash_lookup_region_no_lock - Scan a hash ring looking for an entry for a
+ * given region.
+ *
+ * FIXME: If consecutive queries of the same region are likely, a one-entry
+ * cache would likely be a significant performance win here.
+ */
+static region_t *
+hash_lookup_region_no_lock(region_t *regions, size_t num_entries, region_t r) {
+ size_t index, hash_index;
+ region_t *entry;
+
+ if (!num_entries)
+ return 0;
+
+ index = hash_index = ((uintptr_t)r >> 20) % num_entries;
+ do {
+ entry = regions + index;
+ if (*entry == 0)
+ return 0;
+ if (*entry == r)
+ return entry;
+ if (++index == num_entries)
+ index = 0;
+ } while (index != hash_index);
+ return 0;
+}
+
+/*
+ * hash_region_insert_no_lock - Insert a region into the hash ring.
+ */
+static void
+hash_region_insert_no_lock(region_t *regions, size_t num_entries, region_t r) {
+ size_t index, hash_index;
+ region_t *entry;
+
+ index = hash_index = ((uintptr_t)r >> 20) % num_entries;
+ do {
+ entry = regions + index;
+ if (*entry == 0) {
+ *entry = r;
+ return;
+ }
+ if (++index == num_entries)
+ index = 0;
+ } while (index != hash_index);
+}
+
+/*
+ * hash_regions_alloc_no_lock - Allocate space for a number of entries. This
+ * must be a VM allocation as to avoid recursing between allocating a new small
+ * region, and asking the small region to allocate space for the new list of
+ * regions.
+ */
+static region_t *
+hash_regions_alloc_no_lock(szone_t *szone, size_t num_entries)
+{
+ size_t size = num_entries * sizeof(region_t);
+ return allocate_pages(szone, round_page(size), 0, 0, VM_MEMORY_MALLOC);
+}
+
+/*
+ * hash_regions_grow_no_lock - Grow the hash ring, and rehash the entries.
+ * Return the new region and new size to update the szone. Do not deallocate
+ * the old entries since someone may still be allocating them.
+ */
+static region_t *
+hash_regions_grow_no_lock(szone_t *szone, region_t *regions, size_t old_size,
+ size_t *new_size)
+{
+ // double in size and allocate memory for the regions
+ *new_size = old_size * 2 + 1;
+ region_t *new_regions = hash_regions_alloc_no_lock(szone, *new_size);
+
+ // rehash the entries into the new list
+ size_t index;
+ for (index = 0; index < old_size; ++index) {
+ region_t r = regions[index];
+ if (r != 0)
+ hash_region_insert_no_lock(new_regions, *new_size, r);
+ }
+ return new_regions;
+}
+
+/*******************************************************************************
+ * Large allocator implementation
+ ******************************************************************************/
+#pragma mark large allocator
+
+#if DEBUG_MALLOC
+
+static void
+large_debug_print(szone_t *szone)
+{
+ unsigned num_large_entries = szone->num_large_entries;
+ unsigned index = num_large_entries;
+ large_entry_t *range;
+ _SIMPLE_STRING b = _simple_salloc();
+
+ if (b) {
+ for (index = 0, range = szone->large_entries; index < szone->num_large_entries; index++, range++)
+ if (!LARGE_ENTRY_IS_EMPTY(*range))
+ _simple_sprintf(b, "%d: %p(%y); ", index, LARGE_ENTRY_ADDRESS(*range), LARGE_ENTRY_SIZE(*range));
+
+ _malloc_printf(MALLOC_PRINTF_NOLOG | MALLOC_PRINTF_NOPREFIX, "%s\n", _simple_string(b));
+ _simple_sfree(b);
+ }
+}
+#endif
+
+/*
+ * Scan the hash ring looking for an entry for the given pointer.
+ */
+static 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_shift) % num_large_entries;
+ index = hash_index;
+ do {
+ range = szone->large_entries + index;
+ if (LARGE_ENTRY_MATCHES(*range, ptr))
+ return range;
+ if (LARGE_ENTRY_IS_EMPTY(*range))
+ 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 = (range.address_and_num_pages >> vm_page_shift) % num_large_entries;
+ unsigned index = hash_index;
+ large_entry_t *entry;
+
+ do {
+ entry = szone->large_entries + index;
+ if (LARGE_ENTRY_IS_EMPTY(*entry)) {
+ *entry = range;
+ return; // end of chain
+ }
+ index++;
+ if (index == num_large_entries)
+ index = 0;
+ } while (index != hash_index);
+}
+
+static INLINE void
+large_entries_rehash_after_entry_no_lock(szone_t *szone, large_entry_t *entry)
+{
+ unsigned num_large_entries = szone->num_large_entries;
+ unsigned hash_index = entry - szone->large_entries;
+ unsigned index = hash_index;
+ large_entry_t range;
+
+ do {
+ index++;
+ if (index == num_large_entries)
+ index = 0;
+ range = szone->large_entries[index];
+ if (LARGE_ENTRY_IS_EMPTY(range))
+ return;
+ szone->large_entries[index].address_and_num_pages = 0;
+ large_entry_insert_no_lock(szone, range); // this will reinsert in the
+ // proper place
+ } while (index != hash_index);
+}
+
+static INLINE large_entry_t *
+large_entries_alloc_no_lock(szone_t *szone, unsigned num)
+{
+ size_t size = num * sizeof(large_entry_t);
+ boolean_t is_vm_allocation = size >= LARGE_THRESHOLD;
+
+ if (is_vm_allocation) {
+ // 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
+ return allocate_pages(szone, round_page(size), 0, 0, VM_MEMORY_MALLOC_LARGE);
+ } else {
+ return small_malloc_cleared_no_lock(szone, SMALL_MSIZE_FOR_BYTES(size + SMALL_QUANTUM - 1));
+ }
+}
+
+static void
+large_entries_free_no_lock(szone_t *szone, large_entry_t *entries, unsigned num, vm_range_t *range_to_deallocate)
+{
+ // returns range to deallocate
+ size_t size = num * sizeof(large_entry_t);
+ boolean_t is_vm_allocation = size >= LARGE_THRESHOLD;
+ region_t *region;
+ msize_t msize_and_free;
+
+ if (is_vm_allocation) {
+ range_to_deallocate->address = (vm_address_t)entries;
+ range_to_deallocate->size = round_page(size);
+ } else {
+ range_to_deallocate->size = 0;
+ region = small_region_for_ptr_no_lock(szone, entries);
+ msize_and_free = *SMALL_METADATA_FOR_PTR(entries);
+ if (msize_and_free & SMALL_IS_FREE) {
+ szone_error(szone, "object already freed being freed", entries, NULL);
+ return;
+ }
+ small_free_no_lock(szone, region, entries, msize_and_free);
+ }
+}
+
+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;
+ unsigned new_num_entries = (old_num_entries) ? old_num_entries * 2 + 1 : 63; // always an odd number for good hashing
+ 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 (!LARGE_ENTRY_IS_EMPTY(oldRange)) {
+ 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->size = 0;
+ }
+ return new_entries;
+}
+
+// frees the specific entry in the size table
+// returns a range to truly deallocate
+static vm_range_t
+large_free_no_lock(szone_t *szone, large_entry_t *entry)
+{
+ vm_range_t range;
+
+ range.address = (vm_address_t)LARGE_ENTRY_ADDRESS(*entry);
+ range.size = (vm_size_t)LARGE_ENTRY_SIZE(*entry);
+ szone->num_large_objects_in_use--;
+ szone->num_bytes_in_large_objects -= range.size;
+ if (szone->debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES) {
+ protect((void *)range.address, range.size, VM_PROT_READ | VM_PROT_WRITE, szone->debug_flags);
+ range.address -= vm_page_size;
+ range.size += 2 * vm_page_size;
+ }
+ entry->address_and_num_pages = 0;
+ large_entries_rehash_after_entry_no_lock(szone, entry);
+#if DEBUG_MALLOC
+ if (large_entry_for_pointer_no_lock(szone, (void *)range.address)) {
+ malloc_printf("*** freed entry %p still in use; num_large_entries=%d\n",
+ range.address, szone->num_large_entries);
+ large_debug_print(szone);
+ szone_sleep();
+ }
+#endif
+ return range;
+}
+
+static 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) &&
+ (num_entries * sizeof(large_entry_t) >= LARGE_THRESHOLD)) {
+ range.address = large_entries_address;
+ range.size = round_page(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 (!LARGE_ENTRY_IS_EMPTY(entry)) {
+ range.address = (vm_address_t)LARGE_ENTRY_ADDRESS(entry);
+ range.size = (vm_size_t)LARGE_ENTRY_SIZE(entry);
+ 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;
+}
+
+/********************* HUGE ENTRY UTILITIES ************************/
+
+static huge_entry_t *
+huge_entry_for_pointer_no_lock(szone_t *szone, const void *ptr)
+{
+ unsigned index;
+ huge_entry_t *huge;
+
+ for (index = szone->num_huge_entries, huge = szone->huge_entries;
+ index > 0;
+ index--, huge++) {
+
+ if ((void *)huge->address == ptr)
+ return huge;
+ }
+ return NULL;
+}
+
+static boolean_t
+huge_entry_append(szone_t *szone, huge_entry_t huge)
+{
+ huge_entry_t *new_huge_entries = NULL, *old_huge_entries;
+ unsigned num_huge_entries;
+
+ // We do a little dance with locking because doing allocation (even in the
+ // default szone) may cause something to get freed in this szone, with a
+ // deadlock
+ // Returns 1 on success
+ SZONE_LOCK(szone);
+ for (;;) {
+ num_huge_entries = szone->num_huge_entries;
+ SZONE_UNLOCK(szone);
+ /* check for counter wrap */
+ if ((num_huge_entries + 1) < num_huge_entries)
+ return 0;
+ /* stale allocation from last time around the loop? */
+ if (new_huge_entries)
+ szone_free(szone, new_huge_entries);
+ new_huge_entries = szone_malloc(szone, (num_huge_entries + 1) * sizeof(huge_entry_t));
+ if (new_huge_entries == NULL)
+ return 0;
+ SZONE_LOCK(szone);
+ if (num_huge_entries == szone->num_huge_entries) {
+ // No change - our malloc still applies
+ old_huge_entries = szone->huge_entries;
+ if (num_huge_entries) {
+ memcpy(new_huge_entries, old_huge_entries, num_huge_entries * sizeof(huge_entry_t));
+ }
+ new_huge_entries[szone->num_huge_entries++] = huge;
+ szone->huge_entries = new_huge_entries;
+ SZONE_UNLOCK(szone);
+ szone_free(szone, old_huge_entries);
+ return 1;
+ }
+ // try again!
+ }
+}
+
+static kern_return_t
+huge_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t huge_entries_address, unsigned num_entries, memory_reader_t reader, vm_range_recorder_t recorder)
+{
+ huge_entry_t *entries;
+ kern_return_t err;
+
+ err = reader(task, huge_entries_address, sizeof(huge_entry_t) * num_entries, (void **)&entries);
+ if (err)
+ return err;
+ if (num_entries)
+ recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE | MALLOC_PTR_REGION_RANGE_TYPE, entries, num_entries);
+
+ return 0;
+}
+
+static void *
+large_and_huge_malloc(szone_t *szone, size_t num_pages)
+{
+ void *addr;
+ vm_range_t range_to_deallocate;
+ huge_entry_t huge_entry;
+ size_t size;
+ large_entry_t large_entry;
+
+ if (!num_pages)
+ num_pages = 1; // minimal allocation size for this szone
+ size = (size_t)num_pages << vm_page_shift;
+ range_to_deallocate.size = 0;
+ if (num_pages >= (1 << vm_page_shift)) {
+ addr = allocate_pages(szone, size, 0, szone->debug_flags, VM_MEMORY_MALLOC_HUGE);
+ if (addr == NULL)
+ return NULL;
+ huge_entry.size = size;
+ huge_entry.address = (vm_address_t)addr;
+ if (!huge_entry_append(szone, huge_entry))
+ return NULL; // we are leaking the allocation here
+ SZONE_LOCK(szone);
+ szone->num_bytes_in_huge_objects += size;
+ } else {
+
+ addr = allocate_pages(szone, size, 0, szone->debug_flags, VM_MEMORY_MALLOC_LARGE);
+#if DEBUG_MALLOC
+ if (LOG(szone, addr))
+ malloc_printf("in szone_malloc true large allocation at %p for %ly\n", (void *)addr, size);
+#endif
+ SZONE_LOCK(szone);
+ if (addr == NULL) {
+ SZONE_UNLOCK(szone);
+ return NULL;
+ }
+#if DEBUG_MALLOC
+ if (large_entry_for_pointer_no_lock(szone, addr)) {
+ malloc_printf("freshly allocated is already in use: %p\n", addr);
+ large_debug_print(szone);
+ szone_sleep();
+ }
+#endif
+ 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_and_num_pages = (uintptr_t)addr | num_pages;
+#if DEBUG_MALLOC
+ if (large_entry_for_pointer_no_lock(szone, addr)) {
+ malloc_printf("entry about to be added already in use: %p\n", addr);
+ large_debug_print(szone);
+ szone_sleep();
+ }
+#endif
+ large_entry_insert_no_lock(szone, large_entry);
+#if DEBUG_MALLOC
+ if (!large_entry_for_pointer_no_lock(szone, (void *)addr)) {
+ malloc_printf("can't find entry just added\n");
+ large_debug_print(szone);
+ szone_sleep();
+ }
+#endif
+ szone->num_large_objects_in_use ++;
+ szone->num_bytes_in_large_objects += size;
+ }
+ SZONE_UNLOCK(szone);
+ if (range_to_deallocate.size) {
+ deallocate_pages(szone, (void *)range_to_deallocate.address, range_to_deallocate.size, 0); // we deallocate outside the lock
+ }
+ return (void *)addr;
+}
+
+static INLINE void
+free_large_or_huge(szone_t *szone, void *ptr)
+{
+ // We have established ptr is page-aligned and not tiny nor small
+ large_entry_t *entry;
+ vm_range_t vm_range_to_deallocate;
+ huge_entry_t *huge;
+
+ SZONE_LOCK(szone);
+ entry = large_entry_for_pointer_no_lock(szone, ptr);
+ if (entry) {
+ vm_range_to_deallocate = large_free_no_lock(szone, entry);
+#if DEBUG_MALLOC
+ if (large_entry_for_pointer_no_lock(szone, ptr)) {
+ malloc_printf("*** just after freeing %p still in use num_large_entries=%d\n", ptr, szone->num_large_entries);
+ large_debug_print(szone);
+ szone_sleep();
+ }
+#endif
+ } else if ((huge = huge_entry_for_pointer_no_lock(szone, ptr))) {
+ vm_range_to_deallocate = *huge;
+ *huge = szone->huge_entries[--szone->num_huge_entries]; // last entry fills that spot
+ szone->num_bytes_in_huge_objects -= (size_t)vm_range_to_deallocate.size;
+ } else {
+#if DEBUG_MALLOC
+ large_debug_print(szone);
+#endif
+ szone_error(szone, "pointer being freed was not allocated", ptr, NULL);
+ return;
+ }
+ SZONE_UNLOCK(szone); // we release the lock asap
+ CHECK(szone, __PRETTY_FUNCTION__);
+ // we deallocate_pages, including guard pages
+ if (vm_range_to_deallocate.address) {
+#if DEBUG_MALLOC
+ if (large_entry_for_pointer_no_lock(szone, (void *)vm_range_to_deallocate.address)) {
+ malloc_printf("*** invariant broken: %p still in use num_large_entries=%d\n", vm_range_to_deallocate.address, szone->num_large_entries);
+ large_debug_print(szone);
+ szone_sleep();
+ }
+#endif
+ deallocate_pages(szone, (void *)vm_range_to_deallocate.address, (size_t)vm_range_to_deallocate.size, 0);
+ }
+}
+
+static INLINE int
+try_realloc_large_or_huge_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, saved_entry;
+ huge_entry_t *huge_entry, huge;
+ kern_return_t err;
+
+#if DEBUG_MALLOC
+ if (old_size != ((old_size >> vm_page_shift) << vm_page_shift)) {
+ malloc_printf("*** old_size is %d\n", old_size);
+ }
+#endif
+ SZONE_LOCK(szone);
+ large_entry = large_entry_for_pointer_no_lock(szone, (void *)addr);
+ SZONE_UNLOCK(szone);
+ if (large_entry) {
+ return 0; // large pointer already exists in table - extension is not going to work
+ }
+ new_size = round_page(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);
+ /*
+ * If the new size is still under the large/huge threshold, we can just
+ * extend the existing large block.
+ *
+ * Note: this logic is predicated on the understanding that an allocated
+ * block can never really shrink, so that the new size will always be
+ * larger than the old size.
+ *
+ * Note: the use of 1 << vm_page_shift here has to do with the subdivision
+ * of the bits in the large_entry_t, and not the size of a page (directly).
+ */
+ if ((new_size >> vm_page_shift) < (1 << vm_page_shift)) {
+ /* extend existing large entry */
+ large_entry = large_entry_for_pointer_no_lock(szone, ptr);
+ if (!large_entry) {
+ szone_error(szone, "large entry reallocated is not properly in table", ptr, NULL);
+ /* XXX will cause fault on next reference to entry */
+ }
+ large_entry->address_and_num_pages = (uintptr_t)ptr | (new_size >> vm_page_shift);
+ szone->num_bytes_in_large_objects += new_size - old_size;
+ } else if ((old_size >> vm_page_shift) >= (1 << vm_page_shift)) {
+ /* extend existing huge entry */
+ huge_entry = huge_entry_for_pointer_no_lock(szone, ptr);
+ if (!huge_entry) {
+ szone_error(szone, "huge entry reallocated is not properly in table", ptr, NULL);
+ /* XXX will cause fault on next reference to huge_entry */
+ }
+ huge_entry->size = new_size;
+ szone->num_bytes_in_huge_objects += new_size - old_size;
+ } else {
+ /* need to convert large entry to huge entry */
+
+ /* release large entry, note we still have the VM allocation */
+ large_entry = large_entry_for_pointer_no_lock(szone, ptr);
+ saved_entry = *large_entry; // in case we need to put it back
+ large_free_no_lock(szone, large_entry);
+
+ /* and get a huge entry */
+ huge.address = (vm_address_t)ptr;
+ huge.size = new_size; /* fix up size */
+ SZONE_UNLOCK(szone);
+ if (huge_entry_append(szone, huge)) {
+ szone->num_bytes_in_huge_objects += new_size;
+ return 1; // success!
+ }
+ SZONE_LOCK(szone);
+ // we leak memory (the extra space appended) but data structures are correct
+ large_entry_insert_no_lock(szone, saved_entry); // this will reinsert the large entry
+ }
+ SZONE_UNLOCK(szone); // we release the lock asap
+ return 1;
+}
+
+/********************* Zone call backs ************************/
+
+static void
+szone_free(szone_t *szone, void *ptr)
+{
+ region_t *tiny_region;
+ region_t *small_region;
+
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr))
+ malloc_printf("in szone_free with %p\n", ptr);
+#endif
+ if (!ptr)
+ return;
+ /*
+ * Try to free to a tiny region.
+ */
+ if ((uintptr_t)ptr & (TINY_QUANTUM - 1)) {
+ szone_error(szone, "Non-aligned pointer being freed", ptr, NULL);
+ return;
+ }
+ if ((tiny_region = tiny_region_for_ptr_no_lock(szone, ptr)) != NULL) {
+ if (TINY_INDEX_FOR_PTR(ptr) >= NUM_TINY_BLOCKS) {
+ szone_error(szone, "Pointer to metadata being freed", ptr, NULL);
+ return;
+ }
+ free_tiny(szone, ptr, tiny_region);
+ return;
+ }
+
+ /*
+ * Try to free to a small region.
+ */
+ if ((uintptr_t)ptr & (SMALL_QUANTUM - 1)) {
+ szone_error(szone, "Non-aligned pointer being freed (2)", ptr, NULL);
+ return;
+ }
+ if ((small_region = small_region_for_ptr_no_lock(szone, ptr)) != NULL) {
+ if (SMALL_META_INDEX_FOR_PTR(ptr) >= NUM_SMALL_BLOCKS) {
+ szone_error(szone, "Pointer to metadata being freed (2)", ptr, NULL);
+ return;
+ }
+ free_small(szone, ptr, small_region);
+ return;
+ }
+
+ /* check that it's a legal large/huge allocation */
+ if ((uintptr_t)ptr & (vm_page_size - 1)) {
+ szone_error(szone, "non-page-aligned, non-allocated pointer being freed", ptr, NULL);
+ return;
+ }
+ free_large_or_huge(szone, ptr);
+}
+
+static INLINE void *
+szone_malloc_should_clear(szone_t *szone, size_t size, boolean_t cleared_requested)
+{
+ void *ptr;
+ msize_t msize;
+
+ if (size <= 31*TINY_QUANTUM) {
+ // think tiny
+ msize = TINY_MSIZE_FOR_BYTES(size + TINY_QUANTUM - 1);
+ if (!msize)
+ msize = 1;
+ ptr = tiny_malloc_should_clear(szone, msize, cleared_requested);
+ } else if (!((szone->debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES) && PROTECT_SMALL) && (size < LARGE_THRESHOLD)) {
+ // think small
+ msize = SMALL_MSIZE_FOR_BYTES(size + SMALL_QUANTUM - 1);
+ if (! msize) msize = 1;
+ ptr = small_malloc_should_clear(szone, msize, cleared_requested);
+ } else {
+ // large or huge
+ size_t num_pages = round_page(size) >> vm_page_shift;
+ if (num_pages == 0) /* Overflowed */
+ ptr = 0;
+ else
+ ptr = large_and_huge_malloc(szone, num_pages);
+ }
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr))
+ malloc_printf("szone_malloc returned %p\n", ptr);
+#endif
+ /*
+ * If requested, scribble on allocated memory.
+ */
+ if ((szone->debug_flags & SCALABLE_MALLOC_DO_SCRIBBLE) && ptr && !cleared_requested && size)
+ memset(ptr, 0xaa, size);
+
+ return ptr;
+}
+
+static void *
+szone_malloc(szone_t *szone, size_t size) {
+ return szone_malloc_should_clear(szone, size, 0);
+}
+
+static void *
+szone_calloc(szone_t *szone, size_t num_items, size_t size)
+{
+ size_t total_bytes = num_items * size;
+ if ((num_items > 1) && (size != 0) && ((total_bytes / size) != num_items))
+ return NULL;
+ return szone_malloc_should_clear(szone, total_bytes, 1);
+}
+
+static void *
+szone_valloc(szone_t *szone, size_t size)
+{
+ void *ptr;
+ size_t num_pages;
+
+ num_pages = round_page(size) >> vm_page_shift;
+ ptr = large_and_huge_malloc(szone, num_pages);
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr))
+ malloc_printf("szone_valloc returned %p\n", ptr);
+#endif
+ return ptr;
+}
+
+static size_t
+szone_size(szone_t *szone, const void *ptr)
+{
+ size_t size = 0;
+ boolean_t is_free;
+ msize_t msize, msize_and_free;
+ large_entry_t *entry;
+ huge_entry_t *huge;
+
+ if (!ptr)
+ return 0;
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr)) {
+ malloc_printf("in szone_size for %p (szone=%p)\n", ptr, szone);
+ }
+#endif
+
+ /*
+ * Look for it in a tiny region.
+ */
+ if ((uintptr_t)ptr & (TINY_QUANTUM - 1))
+ return 0;
+ if (tiny_region_for_ptr_no_lock(szone, ptr)) {
+ if (TINY_INDEX_FOR_PTR(ptr) >= NUM_TINY_BLOCKS)
+ return 0;
+ msize = get_tiny_meta_header(ptr, &is_free);
+ return (is_free) ? 0 : TINY_BYTES_FOR_MSIZE(msize);
+ }
+
+ /*
+ * Look for it in a small region.
+ */
+ if ((uintptr_t)ptr & (SMALL_QUANTUM - 1))
+ return 0;
+ if (small_region_for_ptr_no_lock(szone, ptr)) {
+ if (SMALL_META_INDEX_FOR_PTR(ptr) >= NUM_SMALL_BLOCKS)
+ return 0;
+ msize_and_free = *SMALL_METADATA_FOR_PTR(ptr);
+ return (msize_and_free & SMALL_IS_FREE) ? 0 : SMALL_BYTES_FOR_MSIZE(msize_and_free);
+ }
+
+ /*
+ * If not page-aligned, it cannot have come from a large or huge allocation.
+ */
+ if ((uintptr_t)ptr & (vm_page_size - 1))
+ return(0);
+
+ /*
+ * Look for it in a large or huge entry.
+ */
+ SZONE_LOCK(szone);
+ entry = large_entry_for_pointer_no_lock(szone, ptr);
+ if (entry) {
+ size = LARGE_ENTRY_SIZE(*entry);
+ } else if ((huge = huge_entry_for_pointer_no_lock(szone, ptr))) {
+ size = huge->size;
+ }
+ SZONE_UNLOCK(szone);
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr)) {
+ malloc_printf("szone_size for %p returned %d\n", ptr, (unsigned)size);
+ }
+#endif
+ return size;
+}
+
+static void *
+szone_realloc(szone_t *szone, void *ptr, size_t new_size)
+{
+ size_t old_size;
+ void *new_ptr;
+
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr)) {
+ malloc_printf("in szone_realloc for %p, %d\n", ptr, (unsigned)new_size);
+ }
+#endif
+ if (!ptr) {
+ ptr = szone_malloc(szone, new_size);
+ return ptr;
+ }
+ old_size = szone_size(szone, ptr);
+ if (!old_size) {
+ szone_error(szone, "pointer being reallocated was not allocated", ptr, NULL);
+ return NULL;
+ }
+ /* we never shrink an allocation */
+ if (old_size >= new_size)
+ return ptr;
+
+ /*
+ * If the old and new sizes both suit the tiny allocator, try to reallocate in-place.
+ */
+ if ((new_size + TINY_QUANTUM - 1) <= 31 * TINY_QUANTUM) {
+ if (try_realloc_tiny_in_place(szone, ptr, old_size, new_size)) {
+ return ptr;
+ }
+
+ /*
+ * If the old and new sizes both suit the small allocator, and we're not protecting the
+ * small allocations, try to reallocate in-place.
+ */
+ } else if (!((szone->debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES) && PROTECT_SMALL) &&
+ ((new_size + SMALL_QUANTUM - 1) < LARGE_THRESHOLD) &&
+ (old_size > 31 * TINY_QUANTUM)) {
+ if (try_realloc_small_in_place(szone, ptr, old_size, new_size)) {
+ return ptr;
+ }
+
+ /*
+ * If the allocation's a large or huge allocation, try to reallocate in-place there.
+ */
+ } else if (!((szone->debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES) && PROTECT_SMALL) && (old_size > LARGE_THRESHOLD)) {
+ if (try_realloc_large_or_huge_in_place(szone, ptr, old_size, new_size)) {
+ return ptr;
+ }
+ }
+
+ /*
+ * Can't reallocate in place for whatever reason; allocate a new buffer and copy.
+ */
+ new_ptr = szone_malloc(szone, new_size);
+ if (new_ptr == NULL)
+ return NULL;
+
+ /*
+ * If the allocation's large enough, try to copy using VM. If that fails, or
+ * if it's too small, just copy by hand.
+ */
+ if ((old_size < VM_COPY_THRESHOLD) ||
+ vm_copy(mach_task_self(), (vm_address_t)ptr, old_size, (vm_address_t)new_ptr))
+ memcpy(new_ptr, ptr, old_size);
+ szone_free(szone, ptr);
+
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr)) {
+ malloc_printf("szone_realloc returned %p for %d\n", new_ptr, (unsigned)new_size);
+ }
+#endif
+ return new_ptr;
+}
+
+// given a size, returns the number of pointers allocated capable of holding
+// that size, up to the limit specified by the 'count' argument. These pointers
+// are stored in the 'results' array, which must be allocated by the caller.
+// may return zero, since this function is only a best attempt at allocating
+// the pointers. clients should be prepared to call malloc for any additional
+// blocks they need.
+static unsigned
+szone_batch_malloc(szone_t *szone, size_t size, void **results, unsigned count)
+{
+ msize_t msize = TINY_MSIZE_FOR_BYTES(size + TINY_QUANTUM - 1);
+ unsigned found = 0;
+
+ // only bother implementing this for tiny
+ if (size > 31*TINY_QUANTUM)
+ return 0;
+ // make sure to return objects at least one quantum in size
+ if (!msize)
+ msize = 1;
+
+ CHECK(szone, __PRETTY_FUNCTION__);
+
+ // We must lock the zone now, since tiny_malloc_from_free_list assumes that
+ // the caller has done so.
+ SZONE_LOCK(szone);
+
+ // with the zone locked, allocate objects from the free list until all
+ // sufficiently large objects have been exhausted, or we have met our quota
+ // of objects to allocate.
+ while (found < count) {
+ void *ptr = tiny_malloc_from_free_list(szone, msize);
+ if (!ptr)
+ break;
+
+ *results++ = ptr;
+ found++;
+ }
+ SZONE_UNLOCK(szone);
+ return found;
+}
+
+static void
+szone_batch_free(szone_t *szone, void **to_be_freed, unsigned count)
+{
+ unsigned cc = 0;
+ void *ptr;
+ region_t *tiny_region;
+ boolean_t is_free;
+ msize_t msize;
+
+ // frees all the pointers in to_be_freed
+ // note that to_be_freed may be overwritten during the process
+ if (!count)
+ return;
+ CHECK(szone, __PRETTY_FUNCTION__);
+ SZONE_LOCK(szone);
+ while (cc < count) {
+ ptr = to_be_freed[cc];
+ if (ptr) {
+ /* XXX this really slows us down */
+ tiny_region = tiny_region_for_ptr_no_lock(szone, ptr);
+ if (tiny_region) {
+ // this is a tiny pointer
+ if (TINY_INDEX_FOR_PTR(ptr) >= NUM_TINY_BLOCKS)
+ break; // pointer to metadata; let the standard free deal with it
+ msize = get_tiny_meta_header(ptr, &is_free);
+ if (is_free)
+ break; // a double free; let the standard free deal with it
+ tiny_free_no_lock(szone, tiny_region, ptr, msize);
+ to_be_freed[cc] = NULL;
+ }
+ }
+ cc++;
+ }
+ SZONE_UNLOCK(szone);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ while (count--) {
+ ptr = to_be_freed[count];
+ if (ptr)
+ szone_free(szone, ptr);
+ }
+}
+
+static void
+szone_destroy(szone_t *szone)
+{
+ size_t index;
+ large_entry_t *large;
+ vm_range_t range_to_deallocate;
+ huge_entry_t *huge;
+
+ /* destroy large entries */
+ index = szone->num_large_entries;
+ while (index--) {
+ large = szone->large_entries + index;
+ if (!LARGE_ENTRY_IS_EMPTY(*large)) {
+ // we deallocate_pages, including guard pages
+ deallocate_pages(szone, (void *)LARGE_ENTRY_ADDRESS(*large), LARGE_ENTRY_SIZE(*large), szone->debug_flags);
+ }
+ }
+ if (szone->num_large_entries * sizeof(large_entry_t) >= LARGE_THRESHOLD) {
+ // we do not free in the small chunk case
+ large_entries_free_no_lock(szone, szone->large_entries, szone->num_large_entries, &range_to_deallocate);
+ if (range_to_deallocate.size)
+ deallocate_pages(szone, (void *)range_to_deallocate.address, (size_t)range_to_deallocate.size, 0);
+ }
+
+ /* destroy huge entries */
+ index = szone->num_huge_entries;
+ while (index--) {
+ huge = szone->huge_entries + index;
+ deallocate_pages(szone, (void *)huge->address, huge->size, szone->debug_flags);
+ }
+
+ /* destroy tiny regions */
+ for (index = 0; index < szone->num_tiny_regions_allocated; ++index)
+ if (szone->tiny_regions[index])
+ deallocate_pages(szone, szone->tiny_regions[index], TINY_REGION_SIZE, 0);
+
+ /* destroy small regions */
+ for (index = 0; index < szone->num_small_regions_allocated; ++index)
+ if (szone->small_regions[index])
+ deallocate_pages(szone, szone->small_regions[index], SMALL_REGION_SIZE, 0);
+
+ /* destroy region hash rings, if any */
+ if (szone->tiny_regions != szone->initial_tiny_regions) {
+ size_t size = round_page(szone->num_tiny_regions_allocated * sizeof(region_t));
+ deallocate_pages(szone, szone->tiny_regions, size, 0);
+ }
+ if (szone->small_regions != szone->initial_small_regions) {
+ size_t size = round_page(szone->num_small_regions_allocated * sizeof(region_t));
+ deallocate_pages(szone, szone->small_regions, size, 0);
+ }
+ /* Now destroy the separate szone region */
+ deallocate_pages(szone, (void *)szone, SZONE_PAGED_SIZE, SCALABLE_MALLOC_ADD_GUARD_PAGES);
+}
+
+static size_t
+szone_good_size(szone_t *szone, size_t size)
+{
+ msize_t msize;
+ unsigned num_pages;
+
+ if (size <= 31 * TINY_QUANTUM) {
+ // think tiny
+ msize = TINY_MSIZE_FOR_BYTES(size + TINY_QUANTUM - 1);
+ if (! msize) msize = 1;
+ return TINY_BYTES_FOR_MSIZE(msize);
+ }
+ if (!((szone->debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES) && PROTECT_SMALL) && (size < LARGE_THRESHOLD)) {
+ // think small
+ msize = SMALL_MSIZE_FOR_BYTES(size + SMALL_QUANTUM - 1);
+ if (! msize) msize = 1;
+ return SMALL_BYTES_FOR_MSIZE(msize);
+ } else {
+ num_pages = round_page(size) >> vm_page_shift;
+ if (!num_pages)
+ num_pages = 1; // minimal allocation size for this
+ return num_pages << vm_page_shift;
+ }
+}
+
+unsigned szone_check_counter = 0;
+unsigned szone_check_start = 0;
+unsigned szone_check_modulo = 1;
+
+static boolean_t
+szone_check_all(szone_t *szone, const char *function)
+{
+ size_t index;
+
+ SZONE_LOCK(szone);
+ CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
+
+ /* check tiny regions - chould check region count */
+ for (index = 0; index < szone->num_tiny_regions_allocated; ++index) {
+ region_t tiny = szone->tiny_regions[index];
+ if (tiny && !tiny_check_region(szone, tiny)) {
+ SZONE_UNLOCK(szone);
+ szone->debug_flags &= ~ CHECK_REGIONS;
+ szone_error(szone, "check: tiny region incorrect", NULL,
+ "*** tiny region %d incorrect szone_check_all(%s) counter=%d\n",
+ index, function, szone_check_counter);
+ return 0;
+ }
+ }
+ /* check tiny free lists */
+ for (index = 0; index < NUM_TINY_SLOTS; ++index) {
+ if (!tiny_free_list_check(szone, index)) {
+ SZONE_UNLOCK(szone);
+ szone->debug_flags &= ~ CHECK_REGIONS;
+ szone_error(szone, "check: tiny free list incorrect", NULL,
+ "*** tiny free list incorrect (slot=%d) szone_check_all(%s) counter=%d\n",
+ index, function, szone_check_counter);
+ return 0;
+ }
+ }
+ /* check small regions - could check region count */
+ for (index = 0; index < szone->num_small_regions_allocated; ++index) {
+ region_t small = szone->small_regions[index];
+ if (small && !szone_check_small_region(szone, small)) {
+ SZONE_UNLOCK(szone);
+ szone->debug_flags &= ~ CHECK_REGIONS;
+ szone_error(szone, "check: small region incorrect", NULL,
+ "*** small region %d incorrect szone_check_all(%s) counter=%d\n",
+ index, function, szone_check_counter);
+ return 0;
+ }
+ }
+ /* check small free lists */
+ for (index = 0; index < NUM_SMALL_SLOTS; ++index) {
+ if (!small_free_list_check(szone, index)) {
+ SZONE_UNLOCK(szone);
+ szone->debug_flags &= ~ CHECK_REGIONS;
+ szone_error(szone, "check: small free list incorrect", NULL,
+ "*** small free list incorrect (grain=%d) szone_check_all(%s) counter=%d\n",
+ index, function, szone_check_counter);
+ return 0;
+ }
+ }
+ SZONE_UNLOCK(szone);
+ return 1;
+}
+
+static boolean_t
+szone_check(szone_t *szone)
+{
+ if ((++szone_check_counter % 10000) == 0)
+ _malloc_printf(ASL_LEVEL_NOTICE, "at szone_check counter=%d\n", szone_check_counter);
+ if (szone_check_counter < szone_check_start)
+ return 1;
+ if (szone_check_counter % szone_check_modulo)
+ return 1;
+ return szone_check_all(szone, "");
+}
+
+static kern_return_t
+szone_ptr_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t zone_address, memory_reader_t reader, vm_range_recorder_t recorder)
+{
+ szone_t *szone;
+ kern_return_t err;
+
+ if (!reader) reader = _szone_default_reader;
+ err = reader(task, zone_address, sizeof(szone_t), (void **)&szone);
+ if (err) return err;
+ err = tiny_in_use_enumerator(task, context, type_mask, szone, reader, recorder);
+ if (err) return err;
+ err = small_in_use_enumerator(task, context, type_mask, szone, reader, recorder);
+ if (err) return err;
+ err = large_in_use_enumerator(task, context, type_mask,
+ (vm_address_t)szone->large_entries, szone->num_large_entries, reader,
+ recorder);
+ if (err) return err;
+ err = huge_in_use_enumerator(task, context, type_mask,
+ (vm_address_t)szone->huge_entries, szone->num_huge_entries, reader,
+ recorder);
+ return err;
+}
+
+// Following method is deprecated: use scalable_zone_statistics instead
+void
+scalable_zone_info(malloc_zone_t *zone, unsigned *info_to_fill, unsigned count)
+{
+ szone_t *szone = (void *)zone;
+ unsigned info[13];
+
+ // We do not lock to facilitate debug
+ info[4] = szone->num_tiny_objects;
+ info[5] = szone->num_bytes_in_tiny_objects;
+ info[6] = szone->num_small_objects;
+ info[7] = szone->num_bytes_in_small_objects;
+ info[8] = szone->num_large_objects_in_use;
+ info[9] = szone->num_bytes_in_large_objects;
+ info[10] = szone->num_huge_entries;
+ info[11] = szone->num_bytes_in_huge_objects;
+ info[12] = szone->debug_flags;
+ info[0] = info[4] + info[6] + info[8] + info[10];
+ info[1] = info[5] + info[7] + info[9] + info[11];
+ info[3] = szone->num_tiny_regions * TINY_REGION_SIZE + szone->num_small_regions * SMALL_REGION_SIZE + info[9] + info[11];
+ info[2] = info[3] - szone->tiny_bytes_free_at_end - szone->small_bytes_free_at_end;
+ memcpy(info_to_fill, info, sizeof(unsigned)*count);
+}
+
+static void
+szone_print(szone_t *szone, boolean_t verbose)
+{
+ unsigned info[13];
+ size_t index;
+ region_t region;
+
+ SZONE_LOCK(szone);
+ scalable_zone_info((void *)szone, info, 13);
+ _malloc_printf(MALLOC_PRINTF_NOLOG | MALLOC_PRINTF_NOPREFIX,
+ "Scalable zone %p: inUse=%d(%y) touched=%y allocated=%y flags=%d\n",
+ szone, info[0], info[1], info[2], info[3], info[12]);
+ _malloc_printf(MALLOC_PRINTF_NOLOG | MALLOC_PRINTF_NOPREFIX,
+ "\ttiny=%d(%y) small=%d(%y) large=%d(%y) huge=%d(%y)\n",
+ info[4], info[5], info[6], info[7], info[8], info[9], info[10], info[11]);
+ // tiny
+ _malloc_printf(MALLOC_PRINTF_NOLOG | MALLOC_PRINTF_NOPREFIX,
+ "%d tiny regions:\n", szone->num_tiny_regions);
+ for (index = 0; index < szone->num_tiny_regions_allocated; ++index) {
+ region = szone->tiny_regions[index];
+ if (region)
+ print_tiny_region(verbose, region, (region == szone->last_tiny_region) ?
+ szone->tiny_bytes_free_at_end : 0);
+ }
+ if (verbose)
+ print_tiny_free_list(szone);
+ // small
+ _malloc_printf(MALLOC_PRINTF_NOLOG | MALLOC_PRINTF_NOPREFIX,
+ "%d small regions:\n", szone->num_small_regions);
+ for (index = 0; index < szone->num_small_regions_allocated; ++index) {
+ region = szone->small_regions[index];
+ if (region)
+ print_small_region(szone, verbose, region,
+ (region == szone->last_small_region) ?
+ szone->small_bytes_free_at_end : 0);
+ }
+ if (verbose)
+ print_small_free_list(szone);
+ SZONE_UNLOCK(szone);
+}
+
+static void
+szone_log(malloc_zone_t *zone, void *log_address)
+{
+ szone_t *szone = (szone_t *)zone;
+
+ szone->log_address = log_address;
+}
+
+static void
+szone_force_lock(szone_t *szone)
+{
+ SZONE_LOCK(szone);
+}
+
+static void
+szone_force_unlock(szone_t *szone)
+{
+ SZONE_UNLOCK(szone);
+}
+
+boolean_t
+scalable_zone_statistics(malloc_zone_t *zone, malloc_statistics_t *stats, unsigned subzone)
+{
+ szone_t *szone = (szone_t *)zone;
+
+ switch (subzone) {
+ case 0:
+ stats->blocks_in_use = szone->num_tiny_objects;
+ stats->size_in_use = szone->num_bytes_in_tiny_objects;
+ stats->size_allocated = szone->num_tiny_regions * TINY_REGION_SIZE;
+ stats->max_size_in_use = stats->size_allocated - szone->tiny_bytes_free_at_end;
+ return 1;
+ case 1:
+ stats->blocks_in_use = szone->num_small_objects;
+ stats->size_in_use = szone->num_bytes_in_small_objects;
+ stats->size_allocated = szone->num_small_regions * SMALL_REGION_SIZE;
+ stats->max_size_in_use = stats->size_allocated - szone->small_bytes_free_at_end;
+ return 1;
+ case 2:
+ stats->blocks_in_use = szone->num_large_objects_in_use;
+ stats->size_in_use = szone->num_bytes_in_large_objects;
+ stats->max_size_in_use = stats->size_allocated = stats->size_in_use;
+ return 1;
+ case 3:
+ stats->blocks_in_use = szone->num_huge_entries;
+ stats->size_in_use = szone->num_bytes_in_huge_objects;
+ stats->max_size_in_use = stats->size_allocated = stats->size_in_use;
+ return 1;
+ }
+ return 0;
+}
+
+static void
+szone_statistics(szone_t *szone, malloc_statistics_t *stats)
+{
+ size_t big_and_huge;
+
+ stats->blocks_in_use =
+ szone->num_tiny_objects +
+ szone->num_small_objects +
+ szone->num_large_objects_in_use +
+ szone->num_huge_entries;
+ big_and_huge = szone->num_bytes_in_large_objects + szone->num_bytes_in_huge_objects;
+ stats->size_in_use = szone->num_bytes_in_tiny_objects + szone->num_bytes_in_small_objects + big_and_huge;
+ stats->max_size_in_use = stats->size_allocated =
+ szone->num_tiny_regions * TINY_REGION_SIZE +
+ szone->num_small_regions * SMALL_REGION_SIZE +
+ big_and_huge ;
+
+ // Now we account for the untouched areas
+ stats->max_size_in_use -= szone->tiny_bytes_free_at_end;
+ stats->max_size_in_use -= szone->small_bytes_free_at_end;
+}
+
+static const struct malloc_introspection_t szone_introspect = {
+ (void *)szone_ptr_in_use_enumerator,
+ (void *)szone_good_size,
+ (void *)szone_check,
+ (void *)szone_print,
+ szone_log,
+ (void *)szone_force_lock,
+ (void *)szone_force_unlock,
+ (void *)szone_statistics
+}; // marked as const to spare the DATA section
+
+malloc_zone_t *
+create_scalable_zone(size_t initial_size, unsigned debug_flags)
+{
+ szone_t *szone;
+
+ /*
+ * Sanity-check our build-time assumptions about the size of a page.
+ * Since we have sized various things assuming the default page size,
+ * attempting to determine it dynamically is not useful.
+ */
+ if ((vm_page_size != _vm_page_size) || (vm_page_shift != _vm_page_shift)) {
+ malloc_printf("*** FATAL ERROR - machine page size does not match our assumptions.\n");
+ exit(-1);
+ }
+
+ /* get memory for the zone, which is now separate from any region.
+ add guard pages to prevent walking from any other vm allocations
+ to here and overwriting the function pointers in basic_zone. */
+ szone = allocate_pages(NULL, SZONE_PAGED_SIZE, 0,
+ SCALABLE_MALLOC_ADD_GUARD_PAGES,
+ VM_MEMORY_MALLOC);
+ if (!szone)
+ return NULL;
+ /* set up the szone structure */
+ szone->tiny_regions = szone->initial_tiny_regions;
+ szone->small_regions = szone->initial_small_regions;
+ szone->num_tiny_regions_allocated = INITIAL_NUM_REGIONS;
+ szone->num_small_regions_allocated = INITIAL_NUM_REGIONS;
+ szone->basic_zone.version = 3;
+ szone->basic_zone.size = (void *)szone_size;
+ szone->basic_zone.malloc = (void *)szone_malloc;
+ szone->basic_zone.calloc = (void *)szone_calloc;
+ szone->basic_zone.valloc = (void *)szone_valloc;
+ szone->basic_zone.free = (void *)szone_free;
+ szone->basic_zone.realloc = (void *)szone_realloc;
+ szone->basic_zone.destroy = (void *)szone_destroy;
+ szone->basic_zone.batch_malloc = (void *)szone_batch_malloc;
+ szone->basic_zone.batch_free = (void *)szone_batch_free;
+ szone->basic_zone.introspect = (struct malloc_introspection_t *)&szone_introspect;
+ szone->debug_flags = debug_flags;
+ LOCK_INIT(szone->lock);
+
+#if 0
+#warning CHECK_REGIONS enabled
+ debug_flags |= CHECK_REGIONS;
+#endif
+#if 0
+#warning LOG enabled
+ szone->log_address = ~0;
+#endif
+ CHECK(szone, __PRETTY_FUNCTION__);
+ return (malloc_zone_t *)szone;
+}
+
+/********* Support code for emacs unexec ************/
+
+/* History of freezedry version numbers:
+ *
+ * 1) Old malloc (before the scalable malloc implementation in this file
+ * existed).
+ * 2) Original freezedrying code for scalable malloc. This code was apparently
+ * based on the old freezedrying code and was fundamentally flawed in its
+ * assumption that tracking allocated memory regions was adequate to fake
+ * operations on freezedried memory. This doesn't work, since scalable
+ * malloc does not store flags in front of large page-aligned allocations.
+ * 3) Original szone-based freezedrying code.
+ * 4) Fresher malloc with tiny zone
+ * 5) 32/64bit compatible malloc
+ * 6) Metadata within 1MB and 8MB region for tiny and small
+ *
+ * No version backward compatibility is provided, but the version number does
+ * make it possible for malloc_jumpstart() to return an error if the application
+ * was freezedried with an older version of malloc.
+ */
+#define MALLOC_FREEZEDRY_VERSION 6
+
+typedef struct {
+ unsigned version;
+ unsigned nszones;
+ szone_t *szones;
+} malloc_frozen;
+
+static void *
+frozen_malloc(szone_t *zone, size_t new_size)
+{
+ return malloc(new_size);
+}
+
+static void *
+frozen_calloc(szone_t *zone, size_t num_items, size_t size)
+{
+ return calloc(num_items, size);
+}
+
+static void *
+frozen_valloc(szone_t *zone, size_t new_size)
+{
+ return valloc(new_size);
+}
+
+static void *
+frozen_realloc(szone_t *zone, void *ptr, size_t new_size)
+{
+ size_t old_size = szone_size(zone, ptr);
+ void *new_ptr;
+
+ if (new_size <= old_size) {
+ return ptr;
+ }
+ new_ptr = malloc(new_size);
+ if (old_size > 0) {
+ memcpy(new_ptr, ptr, old_size);
+ }
+ return new_ptr;
+}
+
+static void
+frozen_free(szone_t *zone, void *ptr)
+{
+}
+
+static void
+frozen_destroy(szone_t *zone)
+{
+}
+
+/********* Pseudo-private API for emacs unexec ************/
+
+/*
+ * malloc_freezedry() records all of the szones in use, so that they can be
+ * partially reconstituted by malloc_jumpstart(). Due to the differences
+ * between reconstituted memory regions and those created by the szone code,
+ * care is taken not to reallocate from the freezedried memory, except in the
+ * case of a non-growing realloc().
+ *
+ * Due to the flexibility provided by the zone registration mechanism, it is
+ * impossible to implement generic freezedrying for any zone type. This code
+ * only handles applications that use the szone allocator, so malloc_freezedry()
+ * returns 0 (error) if any non-szone zones are encountered.
+ */
+
+uintptr_t
+malloc_freezedry(void)
+{
+ extern unsigned malloc_num_zones;
+ extern malloc_zone_t **malloc_zones;
+ malloc_frozen *data;
+ unsigned i;
+
+ /* Allocate space in which to store the freezedry state. */
+ data = (malloc_frozen *) malloc(sizeof(malloc_frozen));
+
+ /* Set freezedry version number so that malloc_jumpstart() can check for compatibility. */
+ data->version = MALLOC_FREEZEDRY_VERSION;
+
+ /* Allocate the array of szone pointers. */
+ data->nszones = malloc_num_zones;
+ data->szones = (szone_t *) calloc(malloc_num_zones, sizeof(szone_t));
+
+ /*
+ * Fill in the array of szone structures. They are copied rather than
+ * referenced, since the originals are likely to be clobbered during malloc
+ * initialization.
+ */
+ for (i = 0; i < malloc_num_zones; i++) {
+ if (strcmp(malloc_zones[i]->zone_name, "DefaultMallocZone")) {
+ /* Unknown zone type. */
+ free(data->szones);
+ free(data);
+ return 0;
+ }
+ memcpy(&data->szones[i], malloc_zones[i], sizeof(szone_t));
+ }
+
+ return((uintptr_t)data);
+}
+
+int
+malloc_jumpstart(uintptr_t cookie)
+{
+ malloc_frozen *data = (malloc_frozen *)cookie;
+ unsigned i;
+
+ if (data->version != MALLOC_FREEZEDRY_VERSION) {
+ /* Unsupported freezedry version. */
+ return 1;
+ }
+
+ for (i = 0; i < data->nszones; i++) {
+ /* Set function pointers. Even the functions that stay the same must be
+ * set, since there are no guarantees that they will be mapped to the
+ * same addresses. */
+ data->szones[i].basic_zone.size = (void *) szone_size;
+ data->szones[i].basic_zone.malloc = (void *) frozen_malloc;
+ data->szones[i].basic_zone.calloc = (void *) frozen_calloc;
+ data->szones[i].basic_zone.valloc = (void *) frozen_valloc;
+ data->szones[i].basic_zone.free = (void *) frozen_free;
+ data->szones[i].basic_zone.realloc = (void *) frozen_realloc;
+ data->szones[i].basic_zone.destroy = (void *) frozen_destroy;
+ data->szones[i].basic_zone.introspect = (struct malloc_introspection_t *)&szone_introspect;
+
+ /* Register the freezedried zone. */
+ malloc_zone_register(&data->szones[i].basic_zone);
+ }
+
+ return 0;
+}
+