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--- libmalloc/libmalloc-715.140.5/src/magazine_tiny.c
+++ /dev/null
@@ -1,3020 +0,0 @@
-/*
- * Copyright (c) 2015 Apple Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-
-#include "internal.h"
-
-// The address and size of the block in mag_last_free are combined. These
-// macros abstract construction of the combined value and extraction of the
-// size and pointer.
-#define TINY_MAG_LAST_FREE_FROM_PTR_AND_MSIZE(ptr, msize) (void *)(((uintptr_t)(ptr))|((msize_t)msize))
-#define TINY_PTR_FROM_MAG_LAST_FREE(x) (void *)(((uintptr_t)(x)) & ~(TINY_QUANTUM - 1))
-#define TINY_MSIZE_FROM_MAG_LAST_FREE(x) (msize_t)(((uintptr_t)(x)) & (TINY_QUANTUM - 1))
-
-// Adjusts the pointer part of mag_last_free by a given amount in bytes. Must be
-// a multiple of the quantum size (not checked).
-#define TINY_MAG_LAST_FREE_PTR_ADJUST_PTR(x, size) (x) = ((void *)(x) + (size))
-
-// Decrements the size part of mag_last_free by a given msize value. Must not
-// reduce the msize part below zero (not checked).
-#define TINY_MAG_LAST_FREE_PTR_DEC_MSIZE(x, msize_delta) (x) = ((void *)(x) - (msize_delta))
-
-static inline grain_t
-tiny_slot_from_msize(msize_t msize)
-{
- return (!msize || (msize > NUM_TINY_SLOTS) ? NUM_TINY_SLOTS : msize - 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_HEAP_BASE(TINY_REGION_FOR_PTR(ptr))) {
- void *prev_block = (void *)((uintptr_t)ptr - TINY_QUANTUM);
- uint32_t *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;
- }
- msize_t *prev_msize_ptr = &TINY_PREVIOUS_MSIZE(ptr);
- // This is a speculative read of potentially in-use app memory, we need
- // to use _malloc_read_uint16_via_rsp to avoid triggering warnings in
- // memory diagnostic tools.
- return _malloc_read_uint16_via_rsp(prev_msize_ptr);
- }
- // don't read possibly unmapped memory before the beginning of the region
- return 0;
-}
-
-static MALLOC_INLINE void
-set_tiny_meta_header_in_use(const void *ptr, msize_t msize)
-{
- uint32_t *block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
- msize_t index = TINY_INDEX_FOR_PTR(ptr);
- msize_t clr_msize = msize - 1;
- msize_t midx = (index >> 5) << 1;
- uint32_t val = (1 << (index & 31));
-
-#if DEBUG_MALLOC
- if (msize > NUM_TINY_SLOTS) {
- malloc_report(ASL_LEVEL_ERR, "set_tiny_meta_header_in_use() invariant broken %p %d\n", ptr, msize);
- }
- if ((unsigned)index + (unsigned)msize > 0x10000) {
- malloc_report(ASL_LEVEL_ERR, "set_tiny_meta_header_in_use() invariant broken (2) %p %d\n", ptr, msize);
- }
- if (msize > TINY_BITMAP_RANGE_LIMIT) {
- malloc_report(ASL_LEVEL_ERROR, "set_tiny_meta_header_in_use() invariant broken (3) %p %d\n", ptr, msize);
- }
-#endif
-
- block_header[midx] |= val; // BITARRAY_SET(block_header, index);
- block_header[midx + 1] |= val; // BITARRAY_SET(in_use, index);
-
- // bitarray_mclr(block_header, index, end_bit);
- // bitarray_mclr(in_use, index, end_bit);
-
- index++;
- midx = (index >> 5) << 1;
-
- unsigned start = index & 31;
- unsigned end = start + clr_msize;
-
-#if defined(__LP64__)
- if (end > 63) {
- unsigned mask0 = (0xFFFFFFFFU >> (31 - start)) >> 1;
- unsigned mask1 = (0xFFFFFFFFU << (end - 64));
- block_header[midx + 0] &= mask0; // clear header
- block_header[midx + 1] &= mask0; // clear in_use
- block_header[midx + 2] = 0; // clear header
- block_header[midx + 3] = 0; // clear in_use
- block_header[midx + 4] &= mask1; // clear header
- block_header[midx + 5] &= mask1; // clear in_use
- } else
-#endif
- if (end > 31) {
- unsigned mask0 = (0xFFFFFFFFU >> (31 - start)) >> 1;
- unsigned mask1 = (0xFFFFFFFFU << (end - 32));
- block_header[midx + 0] &= mask0;
- block_header[midx + 1] &= mask0;
- block_header[midx + 2] &= mask1;
- block_header[midx + 3] &= mask1;
- } else {
- unsigned mask = (0xFFFFFFFFU >> (31 - start)) >> 1;
- mask |= (0xFFFFFFFFU << end);
- block_header[midx + 0] &= mask;
- block_header[midx + 1] &= mask;
- }
-
- // we set the block_header bit for the following block to reaffirm next block is a block
- index += clr_msize;
- midx = (index >> 5) << 1;
- val = (1 << (index & 31));
- block_header[midx] |= val; // BITARRAY_SET(block_header, (index+clr_msize));
-#if DEBUG_MALLOC
- {
- boolean_t ff;
- msize_t mf;
-
- mf = get_tiny_meta_header(ptr, &ff);
- if (msize != mf) {
- malloc_report(ASL_LEVEL_INFO, "setting header for tiny in_use %p : %d\n", ptr, msize);
- malloc_report(ASL_LEVEL_INFO, "reading header for tiny %p : %d %d\n", ptr, mf, ff);
- }
- }
-#endif
-}
-
-static MALLOC_INLINE void set_tiny_meta_header_in_use_1(const void *ptr) // As above with msize == 1
-{
- uint32_t *block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
- msize_t index = TINY_INDEX_FOR_PTR(ptr);
- msize_t midx = (index >> 5) << 1;
- uint32_t val = (1 << (index & 31));
-
- block_header[midx] |= val; // BITARRAY_SET(block_header, index);
- block_header[midx + 1] |= val; // BITARRAY_SET(in_use, index);
-
- index++;
- midx = (index >> 5) << 1;
- val = (1 << (index & 31));
-
- block_header[midx] |= val; // BITARRAY_SET(block_header, (index+clr_msize))
-}
-
-static MALLOC_INLINE void
-set_tiny_meta_header_middle(const void *ptr)
-{
- // indicates this block is in the middle of an in use block
- uint32_t *block_header;
- uint32_t *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 MALLOC_INLINE void
-zero_tiny_free_inline_meta(void *ptr, msize_t msize)
-{
- if (malloc_zero_policy == MALLOC_ZERO_ON_FREE) {
- *((tiny_free_list_t *)ptr) = (tiny_free_list_t){ 0 };
- if (msize > 1) {
- TINY_FREE_SIZE(ptr) = 0;
- void *follower = FOLLOWING_TINY_PTR(ptr, msize);
- TINY_PREVIOUS_MSIZE(follower) = 0;
- } else if (msize == 0) {
- TINY_FREE_SIZE(ptr) = 0;
- }
- }
-}
-
-static MALLOC_INLINE void
-zero_tiny_free_inline_meta_following(void *ptr, msize_t msize)
-{
- if (malloc_zero_policy == MALLOC_ZERO_ON_FREE) {
- if (msize > 1) {
- void *follower = FOLLOWING_TINY_PTR(ptr, msize);
- TINY_PREVIOUS_MSIZE(follower) = 0;
- }
- }
-}
-
-static MALLOC_COLD MALLOC_NOINLINE void
-tiny_zero_corruption_abort(void *ptr, msize_t msize)
-{
- uint8_t *bytes = ptr;
- size_t size = TINY_BYTES_FOR_MSIZE(msize);
- uint8_t *start = bytes, *end = bytes + size;
- // scan to the first non-NUL byte
- while (*bytes == '\0') {
- bytes++;
- }
-
- unsigned int offset = (unsigned int)(bytes - start);
- malloc_zone_error(MALLOC_ABORT_ON_CORRUPTION, true,
- "Corruption detected in block %p of size %u at offset %u, "
- "first 32 bytes at that offset are "
- "%02X %02X %02X %02X %02X %02X %02X %02X | "
- "%02X %02X %02X %02X %02X %02X %02X %02X | "
- "%02X %02X %02X %02X %02X %02X %02X %02X | "
- "%02X %02X %02X %02X %02X %02X %02X %02X\n",
- ptr, (unsigned int)size, offset,
- (bytes + 0) < end ? *(bytes + 0) : 0,
- (bytes + 1) < end ? *(bytes + 1) : 0,
- (bytes + 2) < end ? *(bytes + 2) : 0,
- (bytes + 3) < end ? *(bytes + 3) : 0,
- (bytes + 4) < end ? *(bytes + 4) : 0,
- (bytes + 5) < end ? *(bytes + 5) : 0,
- (bytes + 6) < end ? *(bytes + 6) : 0,
- (bytes + 7) < end ? *(bytes + 7) : 0,
- (bytes + 8) < end ? *(bytes + 8) : 0,
- (bytes + 9) < end ? *(bytes + 9) : 0,
- (bytes + 10) < end ? *(bytes + 10) : 0,
- (bytes + 11) < end ? *(bytes + 11) : 0,
- (bytes + 12) < end ? *(bytes + 12) : 0,
- (bytes + 13) < end ? *(bytes + 13) : 0,
- (bytes + 14) < end ? *(bytes + 14) : 0,
- (bytes + 15) < end ? *(bytes + 15) : 0,
- (bytes + 16) < end ? *(bytes + 16) : 0,
- (bytes + 17) < end ? *(bytes + 17) : 0,
- (bytes + 18) < end ? *(bytes + 18) : 0,
- (bytes + 19) < end ? *(bytes + 19) : 0,
- (bytes + 20) < end ? *(bytes + 20) : 0,
- (bytes + 21) < end ? *(bytes + 21) : 0,
- (bytes + 22) < end ? *(bytes + 22) : 0,
- (bytes + 23) < end ? *(bytes + 23) : 0,
- (bytes + 24) < end ? *(bytes + 24) : 0,
- (bytes + 25) < end ? *(bytes + 25) : 0,
- (bytes + 26) < end ? *(bytes + 26) : 0,
- (bytes + 27) < end ? *(bytes + 27) : 0,
- (bytes + 28) < end ? *(bytes + 28) : 0,
- (bytes + 29) < end ? *(bytes + 29) : 0,
- (bytes + 30) < end ? *(bytes + 30) : 0,
- (bytes + 31) < end ? *(bytes + 31) : 0);
-}
-
-static MALLOC_INLINE void
-tiny_check_zero_or_clear(void *ptr, msize_t msize, boolean_t clear)
-{
- switch (malloc_zero_policy) {
- case MALLOC_ZERO_ON_FREE:
- if (zero_on_free_should_sample() &&
- _malloc_memcmp_zero_aligned8(ptr, TINY_BYTES_FOR_MSIZE(msize))) {
- tiny_zero_corruption_abort(ptr, msize);
- }
- break;
- case MALLOC_ZERO_NONE:
- if (!clear) {
- break;
- }
- MALLOC_FALLTHROUGH;
- case MALLOC_ZERO_ON_ALLOC:
- memset(ptr, '\0', TINY_BYTES_FOR_MSIZE(msize));
- break;
- }
-}
-
-// Check the inline metadata of a free block that hasn't already been verified:
-// - the previous freelist pointer
-// - agreement of the inline msizes
-//
-// Then clear all the inline metadata.
-static MALLOC_NOINLINE void
-_tiny_check_and_zero_inline_meta_from_freelist(rack_t *rack, void *ptr,
- msize_t msize)
-{
- tiny_free_list_t *free_ptr = ptr;
-
- // check the previous pointer
- (void)free_list_unchecksum_ptr(rack, &free_ptr->previous);
- // zero both pointers
- *free_ptr = (tiny_free_list_t){ 0 };
-
- // check agreement between msizes and zero
- if (msize > 1) {
- msize_t leading_free_size = TINY_FREE_SIZE(ptr);
- void *follower = FOLLOWING_TINY_PTR(ptr, msize);
- msize_t trailing_free_size = TINY_PREVIOUS_MSIZE(follower);
-
- if (leading_free_size != trailing_free_size) {
- malloc_zone_error(MALLOC_ABORT_ON_CORRUPTION, true,
- "Corruption of free object %p: msizes %u/%u disagree\n",
- ptr, leading_free_size, trailing_free_size);
- } else if (leading_free_size != msize) {
- malloc_zone_error(MALLOC_ABORT_ON_CORRUPTION, true,
- "Corruption at %p: unexpected msizes %u/%u\n",
- ptr, leading_free_size, msize);
- }
-
- TINY_FREE_SIZE(ptr) = 0;
- TINY_PREVIOUS_MSIZE(follower) = 0;
- } else if (msize == 0 && TINY_FREE_SIZE(ptr) != 0) {
- malloc_zone_error(MALLOC_ABORT_ON_CORRUPTION, true,
- "Corruption at %p: unexpected nonzero msize %u\n", ptr,
- TINY_FREE_SIZE(ptr));
- }
-}
-
-static MALLOC_ALWAYS_INLINE MALLOC_INLINE void
-tiny_check_and_zero_inline_meta_from_freelist(rack_t *rack, void *ptr,
- msize_t msize)
-{
- if (malloc_zero_policy != MALLOC_ZERO_ON_FREE) {
- return;
- }
-
- _tiny_check_and_zero_inline_meta_from_freelist(rack, ptr, msize);
-}
-
-
-static MALLOC_INLINE void
-set_tiny_meta_header_free(const void *ptr, msize_t msize)
-{
- // !msize is acceptable and means 65536
- uint32_t *block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
- msize_t index = TINY_INDEX_FOR_PTR(ptr);
- msize_t midx = (index >> 5) << 1;
- uint32_t val = (1 << (index & 31));
-
-#if DEBUG_MALLOC
- if ((unsigned)index + (unsigned)msize > 0x10000) {
- malloc_report(ASL_LEVEL_ERR, "setting header for tiny free %p msize too large: %d\n", ptr, msize);
- }
-#endif
-
- block_header[midx] |= val; // BITARRAY_SET(block_header, index);
- block_header[midx + 1] &= ~val; // 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_report(ASL_LEVEL_INFO, "setting header for tiny free %p : %u\n", ptr, msize);
- malloc_report(ASL_LEVEL_INFO, "reading header for tiny %p : %u %u\n", ptr, mf, ff);
- }
-#endif
-}
-
-static MALLOC_INLINE boolean_t
-tiny_meta_header_is_free(const void *ptr)
-{
- uint32_t *block_header;
- uint32_t *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 MALLOC_INLINE void *
-tiny_previous_preceding_free(void *ptr, msize_t *prev_msize)
-{
- // returns the previous block, assuming and verifying it's free
- uint32_t *block_header;
- uint32_t *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 = TINY_PTR_FOR_INDEX(previous_index, TINY_REGION_FOR_PTR(ptr));
- 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;
-}
-
-// Given a region and a slot index, scans regions that precede the region on
-// the magazine region list for one that has something on its free list for
-// the given slot and returns the address of the last such block, or NULL if
-// there is none. To reduce overhead, we scan forward from the first region
-// looking for our region and noting the last on the freelist for the given slot
-// for each earlier region, stopping once we have looked at 5 regions if we did
-// not reach our own. This has the effect of keeping the blocks for early
-// regions near the front of the freelist while not spending large amounts of
-// time looking for the "best" place to put this region's free blocks when there
-// are many regions in the magazine.
-static MALLOC_INLINE void *
-tiny_earlier_region_last_free(magazine_t *tiny_mag_ptr,
- region_trailer_t *trailer, grain_t slot)
-{
- int count = 0;
- uint16_t target_block = 0;
- region_trailer_t *target_trailer = NULL;
- region_trailer_t *next_trailer = tiny_mag_ptr->firstNode;
-
- while (next_trailer && next_trailer != trailer && count++ < 5) {
- tiny_region_t r = TINY_REGION_FOR_PTR(next_trailer);
- uint16_t block = r->free_blocks_by_slot[slot].last_block;
- if (block) {
- target_block = block;
- target_trailer = next_trailer;
- }
- next_trailer = next_trailer->next;
- }
- return target_block ? TINY_PTR_FOR_INDEX(target_block - 1,
- TINY_REGION_FOR_PTR(target_trailer)) : NULL;
-}
-
-static MALLOC_INLINE void
-tiny_update_region_free_list_for_remove(grain_t slot, tiny_free_list_t *ptr,
- tiny_free_list_t *new_head)
-{
- uint16_t ptr_index = TINY_INDEX_FOR_PTR(ptr);
- tiny_region_t ptr_region = TINY_REGION_FOR_PTR(ptr);
- region_free_blocks_t *blocks = &ptr_region->free_blocks_by_slot[slot];
- MALLOC_ASSERT(ptr_index == blocks->first_block - 1);
-
- if (new_head && (TINY_REGION_FOR_PTR(new_head) == TINY_REGION_FOR_PTR(ptr))) {
- uint16_t new_head_block = TINY_INDEX_FOR_PTR(new_head) + 1;
- if (blocks->first_block == blocks->last_block) {
- blocks->last_block = new_head_block;
- }
- blocks->first_block = new_head_block;
- } else {
- // No more entries in this region.
- blocks->first_block = blocks->last_block = 0;
- }
-}
-
-void
-tiny_print_region_free_list(void *ptr, grain_t slot)
-{
- tiny_region_t region = TINY_REGION_FOR_PTR(ptr);
- region_free_blocks_t *blocks = ®ion->free_blocks_by_slot[slot];
- malloc_printf("For region %p, first block: %d (%p), last block: %d (%p)\n",
- region,
- blocks->first_block,
- blocks->first_block ? TINY_PTR_FOR_INDEX(blocks->first_block - 1, region) : (void *)0,
- blocks->last_block,
- blocks->last_block ? TINY_PTR_FOR_INDEX(blocks->last_block - 1, region) : (void *)0);
-}
-
-/*
- * 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(rack_t *rack, magazine_t *tiny_mag_ptr, void *ptr, msize_t msize)
-{
- grain_t slot = (!msize || (msize > NUM_TINY_SLOTS)) ? NUM_TINY_SLOTS : msize - 1;
- tiny_free_list_t *free_ptr = ptr;
- tiny_free_list_t *free_head = tiny_mag_ptr->mag_free_list[slot].p;
-
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "in %s, ptr=%p, msize=%d\n", __FUNCTION__, ptr, msize);
- }
- if (((uintptr_t)ptr) & (TINY_QUANTUM - 1)) {
- malloc_zone_error(rack->debug_flags, true, "tiny_free_list_add_ptr: Unaligned ptr: %p\n", ptr);
- }
-#endif
- set_tiny_meta_header_free(ptr, msize);
- if (free_head) {
-#if DEBUG_MALLOC
- if (free_list_unchecksum_ptr(szone, &free_head->previous)) {
- malloc_zone_error(rack->debug_flags, true,
- "tiny_free_list_add_ptr: Internal invariant broken (free_head->previous): "
- "ptr=%p slot=%d free_head=%p previous=%p\n", ptr, slot, (void *)free_head, free_head->previous.p);
- }
- if (!tiny_meta_header_is_free(free_head)) {
- malloc_zone_error(rack->debug_flags, true,
- "tiny_free_list_add_ptr: Internal invariant broken (free_head is not a free pointer): "
- "ptr=%p slot=%d free_head=%p\n", ptr, slot, (void *)free_head);
- }
-#endif
- } else {
- BITMAPV_SET(tiny_mag_ptr->mag_bitmap, slot);
- }
-
- tiny_region_t region = TINY_REGION_FOR_PTR(ptr);
- region_free_blocks_t *free_blocks = ®ion->free_blocks_by_slot[slot];
- uint16_t first_free_block_index = free_blocks->first_block;
- uint16_t this_block_index = TINY_INDEX_FOR_PTR(ptr);
-
- if (first_free_block_index) {
- // This region already has something on its free list.
- tiny_free_list_t *old_first_free = TINY_PTR_FOR_INDEX(first_free_block_index - 1, region);
- tiny_free_list_t *prev_ptr = free_list_unchecksum_ptr(rack, &old_first_free->previous);
- if (!prev_ptr) {
- // Old first item was the first item in the magazine free list -
- // update the magazine head pointer to point to this block.
- tiny_mag_ptr->mag_free_list[slot].p = free_ptr;
- } else {
- prev_ptr->next.u = free_list_checksum_ptr(rack, free_ptr); // XXX
- }
-
- // Set our previous pointer to the one from the old first block.
- // It's already checksummed, so just copy it directly. It is NULL if
- // the old first block was also the first block on the magazine free
- // list.
- free_ptr->previous.u = old_first_free->previous.u;
-
- // Our "next" pointer always points to the block that used to be first
- // and we are always its predecessor.
- free_ptr->next.u = free_list_checksum_ptr(rack, old_first_free);
- old_first_free->previous.u = free_list_checksum_ptr(rack, free_ptr);
-
- // Update the first free block index for this region.
- free_blocks->first_block = this_block_index + 1;
- } else {
- // Free list for this region is empty. Add ourselves to the magazine
- // free list between the last block of the preceding region that has
- // a free block and the first block of the next region with a free
- // block (either of which may not exist).
- tiny_free_list_t *prev_free = NULL;
- tiny_free_list_t *next_free;
-
- // If the magazine free list is empty, we know we are going to add at
- // the front. Otherwise, find the correct place. If we are freeing to
- // the recirc depot, we can always free to the front because we don't
- // care about ordering in the depot (since no allocations occur there).
- mag_index_t mag_index = MAGAZINE_INDEX_FOR_TINY_REGION(region);
- if (mag_index != DEPOT_MAGAZINE_INDEX
- && tiny_mag_ptr->mag_free_list[slot].p) {
- region_trailer_t *trailer = REGION_TRAILER_FOR_TINY_REGION(region);
- prev_free = tiny_earlier_region_last_free(tiny_mag_ptr, trailer, slot);
- }
- if (!prev_free) {
- // We are becoming the head of the magazine free list.
- next_free = tiny_mag_ptr->mag_free_list[slot].p;
- tiny_mag_ptr->mag_free_list[slot].p = free_ptr;
- } else {
- next_free = free_list_unchecksum_ptr(rack, &prev_free->next);
- prev_free->next.u = free_list_checksum_ptr(rack, free_ptr);
- }
- free_ptr->previous.u = free_list_checksum_ptr(rack, prev_free);
-
- if (next_free) {
- next_free->previous.u = free_list_checksum_ptr(rack, free_ptr);
- }
- free_ptr->next.u = free_list_checksum_ptr(rack, next_free);
-
- // Set the first and last free block index for this region.
- free_blocks->first_block = free_blocks->last_block =
- this_block_index + 1;
- }
-}
-
-/*
- * Removes the item pointed to by ptr in the proper free list.
- * Assumes szone has been locked
- */
-static void
-tiny_free_list_remove_ptr(rack_t *rack, magazine_t *tiny_mag_ptr, void *ptr, msize_t msize)
-{
- grain_t slot = tiny_slot_from_msize(msize);
- tiny_free_list_t *free_ptr = ptr, *next, *previous;
-
- next = free_list_unchecksum_ptr(rack, &free_ptr->next);
- previous = free_list_unchecksum_ptr(rack, &free_ptr->previous);
-
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "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 (tiny_mag_ptr->mag_free_list[slot] != ptr) {
- malloc_zone_error(rack->debug_flags, true,
- "tiny_free_list_remove_ptr: Internal invariant broken (tiny_mag_ptr->mag_free_list[slot]): "
- "ptr=%p slot=%d msize=%d tiny_mag_ptr->mag_free_list[slot]=%p\n", ptr, slot, msize,
- (void *)tiny_mag_ptr->mag_free_list[slot]);
- return;
- }
-#endif
- tiny_mag_ptr->mag_free_list[slot].p = next;
- if (!next) {
- BITMAPV_CLR(tiny_mag_ptr->mag_bitmap, slot);
- }
- } else {
- // Check that the next pointer of "previous" points to free_ptr.
- tiny_free_list_t *prev_next = free_list_unchecksum_ptr(rack, &previous->next);
- if (prev_next != free_ptr) {
- malloc_zone_error(rack->debug_flags, true,
- "tiny_free_list_remove_ptr: Internal invariant broken (next ptr of prev): "
- "ptr=%p, prev_next=%p\n", ptr, prev_next);
- __builtin_unreachable(); // Always crashes in malloc_zone_error().
- }
-
- // We know free_ptr is already checksummed, so we don't need to do it
- // again.
- previous->next = free_ptr->next;
- }
- if (next) {
- // Check that the previous pointer of "next" points to free_ptr.
- tiny_free_list_t *next_prev = free_list_unchecksum_ptr(rack, &next->previous);
- if (next_prev != free_ptr) {
- malloc_zone_error(rack->debug_flags, true,
- "tiny_free_list_remove_ptr: Internal invariant broken (prev ptr of next): "
- "ptr=%p, next_prev=%p\n", ptr, next_prev);
- __builtin_unreachable(); // Always crashes in malloc_zone_error().
- }
-
- // We know free_ptr is already checksummed, so we don't need to do it
- // again.
- next->previous = free_ptr->previous;
- }
-
- tiny_region_t region = TINY_REGION_FOR_PTR(ptr);
- region_free_blocks_t *free_blocks = ®ion->free_blocks_by_slot[slot];
- uint16_t this_block_index = TINY_INDEX_FOR_PTR(ptr);
-
- boolean_t is_first = free_blocks->first_block == this_block_index + 1;
- boolean_t is_last = free_blocks->last_block == this_block_index + 1;
-
- if (is_first && is_last) {
- // Removing the one and only item on the list. Set both block indices to 0.
- free_blocks->first_block = free_blocks->last_block = 0;
- } else if (is_first) {
- MALLOC_ASSERT(next);
- free_blocks->first_block = TINY_INDEX_FOR_PTR(next) + 1;
- } else if (is_last) {
- MALLOC_ASSERT(previous);
- free_blocks->last_block = TINY_INDEX_FOR_PTR(previous) + 1;
- }
-}
-
-void
-tiny_finalize_region(rack_t *rack, magazine_t *tiny_mag_ptr)
-{
- void *last_block, *previous_block;
- uint32_t *last_header;
- msize_t last_msize, previous_msize, last_index;
-
- // It is possible that the block prior to the last block in the region has
- // been free'd, but was not coalesced with the free bytes at the end of the
- // block, since we treat the bytes at the end of the region as "in use" in
- // the meta headers. Attempt to coalesce the last block with the previous
- // block, so we don't violate the "no consecutive free blocks" invariant.
- //
- // FIXME: Need to investigate how much work would be required to increase
- // 'mag_bytes_free_at_end' when freeing the preceding block, rather
- // than performing this workaround.
- //
-
- if (tiny_mag_ptr->mag_bytes_free_at_end) {
- last_block = (void *)((uintptr_t)TINY_REGION_HEAP_END(tiny_mag_ptr->mag_last_region) - tiny_mag_ptr->mag_bytes_free_at_end);
- last_msize = TINY_MSIZE_FOR_BYTES(tiny_mag_ptr->mag_bytes_free_at_end);
- last_header = TINY_BLOCK_HEADER_FOR_PTR(last_block);
- last_index = TINY_INDEX_FOR_PTR(last_block);
-
- // Before anything we transform any remaining mag_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 mag_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 (last_index != (NUM_TINY_BLOCKS - 1)) {
- BITARRAY_CLR(last_header, (last_index + 1));
- }
-
- previous_block = tiny_previous_preceding_free(last_block, &previous_msize);
- if (previous_block) {
- set_tiny_meta_header_middle(last_block);
- tiny_free_list_remove_ptr(rack, tiny_mag_ptr, previous_block, previous_msize);
- // zero out the trailing inline msize of the previous block to
- // connect its zero prefix to the last block
- zero_tiny_free_inline_meta_following(previous_block, previous_msize);
- last_block = previous_block;
- last_msize += previous_msize;
- }
-
- // splice last_block into the free list
- tiny_free_list_add_ptr(rack, tiny_mag_ptr, last_block, last_msize);
- tiny_mag_ptr->mag_bytes_free_at_end = 0;
- }
-
-#if CONFIG_ASLR_INTERNAL
- // Coalesce the big free block at start with any following free blocks
- if (tiny_mag_ptr->mag_bytes_free_at_start) {
- last_block = TINY_REGION_HEAP_BASE(tiny_mag_ptr->mag_last_region);
- last_msize = TINY_MSIZE_FOR_BYTES(tiny_mag_ptr->mag_bytes_free_at_start);
-
- void *next_block = (void *)((uintptr_t)last_block + tiny_mag_ptr->mag_bytes_free_at_start);
-
- // clear the in use bit we were using to mark the end of the big start block
- set_tiny_meta_header_middle((void *)((uintptr_t)next_block - TINY_QUANTUM));
-
- // Coalesce the big start block with any following free blocks
- if (tiny_meta_header_is_free(next_block)) {
- msize_t next_msize = get_tiny_free_size(next_block);
- set_tiny_meta_header_middle(next_block);
- tiny_free_list_remove_ptr(rack, tiny_mag_ptr, next_block, next_msize);
- // zero inline metadata of next_block to continue the zero prefix of
- // the big starting free block
- zero_tiny_free_inline_meta(next_block, next_msize);
- last_msize += next_msize;
- }
-
- // splice last_block into the free list
- tiny_free_list_add_ptr(rack, tiny_mag_ptr, last_block, last_msize);
- tiny_mag_ptr->mag_bytes_free_at_start = 0;
- }
-#endif
-
- tiny_mag_ptr->mag_last_region = NULL;
-}
-
-int
-tiny_free_detach_region(rack_t *rack, magazine_t *tiny_mag_ptr, region_t r)
-{
- uintptr_t start = (uintptr_t)TINY_REGION_HEAP_BASE(r);
- uintptr_t current = start;
- uintptr_t limit = (uintptr_t)TINY_REGION_HEAP_END(r);
- boolean_t is_free;
- msize_t msize;
- region_trailer_t *trailer = REGION_TRAILER_FOR_TINY_REGION(r);
-
- 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) {
-#if DEBUG_MALLOC
- malloc_report(ASL_LEVEL_ERR, "*** tiny_free_detach_region error with %p: msize=%d is_free=%d\n", (void *)current, msize, is_free);
-#endif
- break;
- }
- if (is_free) {
- tiny_free_list_remove_ptr(rack, tiny_mag_ptr, (void *)current, msize);
- }
- current += TINY_BYTES_FOR_MSIZE(msize);
- }
- return trailer->objects_in_use;
-}
-
-size_t
-tiny_free_reattach_region(rack_t *rack, magazine_t *tiny_mag_ptr, region_t r)
-{
- uintptr_t start = (uintptr_t)TINY_REGION_HEAP_BASE(r);
- uintptr_t current = start;
- uintptr_t limit = (uintptr_t)TINY_REGION_HEAP_END(r);
- boolean_t is_free;
- msize_t msize;
- size_t bytes_used = REGION_TRAILER_FOR_TINY_REGION(r)->bytes_used;
-
- 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) {
-#if DEBUG_MALLOC
- malloc_report(ASL_LEVEL_ERR, "*** tiny_free_reattach_region error with %p: msize=%d is_free=%d\n", (void *)current, msize, is_free);
-#endif
- break;
- }
- if (is_free) {
- tiny_free_list_add_ptr(rack, tiny_mag_ptr, (void *)current, msize);
- }
- current += TINY_BYTES_FOR_MSIZE(msize);
- }
- return bytes_used;
-}
-
-typedef struct {
- uint8_t pnum, size;
-} tiny_pg_pair_t;
-
-void
-tiny_free_scan_madvise_free(rack_t *rack, magazine_t *depot_ptr, region_t r)
-{
- uintptr_t start = (uintptr_t)TINY_REGION_HEAP_BASE(r);
- uintptr_t current = start;
- uintptr_t limit = (uintptr_t)TINY_REGION_HEAP_END(r);
- boolean_t is_free;
- msize_t msize;
- tiny_pg_pair_t advisory[((TINY_HEAP_SIZE + vm_kernel_page_size - 1) >> vm_kernel_page_shift) >>
- 1]; // 256bytes stack allocated
- int advisories = 0;
-
- // Scan the metadata identifying blocks which span one or more pages. Mark the pages MADV_FREE taking care to preserve free list
- // management data.
- while (current < limit) {
- msize = get_tiny_meta_header((void *)current, &is_free);
- if (is_free && !msize && (current == start)) {
- // first block is all free
-#if DEBUG_MALLOC
- malloc_report(ASL_LEVEL_INFO, "*** tiny_free_scan_madvise_free first block is all free! %p: msize=%d is_free=%d\n", (void *)current,
- msize, is_free);
-#endif
- uintptr_t pgLo = round_page_kernel(start + sizeof(tiny_free_list_t) + sizeof(msize_t));
- uintptr_t pgHi = trunc_page_kernel(start + TINY_REGION_SIZE - sizeof(msize_t));
-
- if (pgLo < pgHi) {
- advisory[advisories].pnum = (pgLo - start) >> vm_kernel_page_shift;
- advisory[advisories].size = (pgHi - pgLo) >> vm_kernel_page_shift;
- advisories++;
- }
- break;
- }
- if (!msize) {
-#if DEBUG_MALLOC
- malloc_report(ASL_LEVEL_ERR, "*** tiny_free_scan_madvise_free error with %p: msize=%d is_free=%d\n", (void *)current, msize, is_free);
-#endif
- break;
- }
- if (is_free) {
- uintptr_t pgLo = round_page_kernel(current + sizeof(tiny_free_list_t) + sizeof(msize_t));
- uintptr_t pgHi = trunc_page_kernel(current + TINY_BYTES_FOR_MSIZE(msize) - sizeof(msize_t));
-
- if (pgLo < pgHi) {
- advisory[advisories].pnum = (pgLo - (uintptr_t)r) >> vm_kernel_page_shift;
- advisory[advisories].size = (pgHi - pgLo) >> vm_kernel_page_shift;
- advisories++;
- }
- }
- current += TINY_BYTES_FOR_MSIZE(msize);
- }
-
- if (advisories > 0) {
- int i;
-
- // So long as the following hold for this region:
- // (1) No malloc()'s are ever performed from the depot (hence free pages remain free,)
- // (2) The region is not handed over to a per-CPU magazine (where malloc()'s could be performed),
- // (3) The entire region is not mumap()'d (so the madvise's are applied to the intended addresses),
- // then the madvise opportunities collected just above can be applied outside all locks.
- // (1) is ensured by design, (2) and (3) are ensured by bumping the globally visible counter node->pinned_to_depot.
-
- OSAtomicIncrement32Barrier(&(REGION_TRAILER_FOR_TINY_REGION(r)->pinned_to_depot));
- SZONE_MAGAZINE_PTR_UNLOCK(depot_ptr);
- for (i = 0; i < advisories; ++i) {
- uintptr_t addr = (advisory[i].pnum << vm_kernel_page_shift) + (uintptr_t)r;
- size_t size = advisory[i].size << vm_kernel_page_shift;
-
- mvm_madvise_free(rack, r, addr, addr + size, NULL, rack->debug_flags & MALLOC_DO_SCRIBBLE);
- }
- SZONE_MAGAZINE_PTR_LOCK(depot_ptr);
- OSAtomicDecrement32Barrier(&(REGION_TRAILER_FOR_TINY_REGION(r)->pinned_to_depot));
- }
-}
-
-#if CONFIG_RECIRC_DEPOT
-static region_t
-tiny_find_msize_region(rack_t *rack, magazine_t *tiny_mag_ptr, mag_index_t mag_index, msize_t msize)
-{
- tiny_free_list_t *ptr;
- grain_t slot = tiny_slot_from_msize(msize);
- free_list_t *free_list = tiny_mag_ptr->mag_free_list;
- free_list_t *the_slot = free_list + slot;
- free_list_t *limit;
-#if defined(__LP64__)
- uint64_t bitmap;
-#else
- uint32_t bitmap;
-#endif
- // Assumes we've locked the magazine
- CHECK_MAGAZINE_PTR_LOCKED(szone, tiny_mag_ptr, __PRETTY_FUNCTION__);
-
- // Look for an exact match by checking the freelist for this msize.
- ptr = the_slot->p;
- if (ptr) {
- return TINY_REGION_FOR_PTR(ptr);
- }
-
- // 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 defined(__LP64__)
- bitmap = ((uint64_t *)(tiny_mag_ptr->mag_bitmap))[0] & ~((1ULL << slot) - 1);
-#else
- bitmap = tiny_mag_ptr->mag_bitmap[0] & ~((1 << slot) - 1);
-#endif
- if (!bitmap) {
- return NULL;
- }
-
- slot = BITMAPV_CTZ(bitmap);
- limit = free_list + NUM_TINY_SLOTS;
- free_list += slot;
-
- if (free_list < limit) {
- ptr = free_list->p;
- if (ptr) {
- return TINY_REGION_FOR_PTR(ptr);
- } else {
- /* Shouldn't happen. Fall through to look at last slot. */
-#if DEBUG_MALLOC
- malloc_report(ASL_LEVEL_ERR, "in tiny_find_msize_region(), mag_bitmap out of sync, slot=%d\n", slot);
-#endif
- }
- }
-
- // We are now looking at the last slot, which contains blocks equal to, or
- // due to coalescing of free blocks, larger than NUM_TINY_SLOTS * tiny quantum size.
- ptr = limit->p;
- if (ptr) {
- return TINY_REGION_FOR_PTR(ptr);
- }
-
- return NULL;
-}
-#endif // CONFIG_RECIRC_DEPOT
-
-#if CONFIG_MADVISE_PRESSURE_RELIEF
-void
-tiny_madvise_pressure_relief(rack_t *rack)
-{
- mag_index_t mag_index;
- magazine_t *tiny_depot_ptr = (&rack->magazines[DEPOT_MAGAZINE_INDEX]);
-
- for (mag_index = 0; mag_index < rack->num_magazines; mag_index++) {
- size_t index;
- for (index = 0; index < rack->region_generation->num_regions_allocated; ++index) {
- rack_region_lock(rack);
-
- region_t tiny = rack->region_generation->hashed_regions[index];
- if (!tiny || tiny == HASHRING_REGION_DEALLOCATED) {
- rack_region_unlock(rack);
- continue;
- }
-
- region_trailer_t *trailer = REGION_TRAILER_FOR_TINY_REGION(tiny);
- // Make sure that the owning magazine doesn't try and take this out
- // from under our feet.
- trailer->dispose_flags |= RACK_DISPOSE_DELAY;
- rack_region_unlock(rack);
-
- magazine_t *mag_ptr = mag_lock_zine_for_region_trailer(rack->magazines,
- trailer, MAGAZINE_INDEX_FOR_TINY_REGION(tiny));
-
- // If acquiring the region lock was enough to prevent the owning
- // magazine from deallocating the region, free it now so we don't
- // do wasted work.
- if (rack_region_maybe_dispose(rack, tiny, TINY_REGION_SIZE, trailer)) {
- SZONE_MAGAZINE_PTR_UNLOCK(mag_ptr);
- continue;
- }
-
- /* Ordering is important here, the magazine of a region may potentially change
- * during mag_lock_zine_for_region_trailer, so src_mag_index must be taken
- * after we've obtained the lock.
- */
- mag_index_t src_mag_index = MAGAZINE_INDEX_FOR_TINY_REGION(tiny);
-
- /* We can (and must) ignore magazines that are already in the recirc depot. */
- if (src_mag_index == DEPOT_MAGAZINE_INDEX) {
- SZONE_MAGAZINE_PTR_UNLOCK(mag_ptr);
- continue;
- }
-
- if (REGION_TRAILER_FOR_TINY_REGION(tiny)->pinned_to_depot > 0) {
- SZONE_MAGAZINE_PTR_UNLOCK(mag_ptr);
- continue;
- }
-
- if (tiny == mag_ptr->mag_last_region && (mag_ptr->mag_bytes_free_at_end || mag_ptr->mag_bytes_free_at_start)) {
- tiny_finalize_region(rack, mag_ptr);
- }
-
- /* Because this region is currently in use, we can't safely madvise it while
- * it's attached to the magazine. For this operation we have to remove it from
- * the current mag, attach it to the depot and then madvise.
- */
-
- recirc_list_extract(rack, mag_ptr, REGION_TRAILER_FOR_TINY_REGION(tiny));
- int objects_in_use = tiny_free_detach_region(rack, mag_ptr, tiny);
-
- SZONE_MAGAZINE_PTR_LOCK(tiny_depot_ptr);
- MAGAZINE_INDEX_FOR_TINY_REGION(tiny) = DEPOT_MAGAZINE_INDEX;
- MALLOC_ASSERT(REGION_TRAILER_FOR_TINY_REGION(tiny)->pinned_to_depot == 0);
-
- size_t bytes_inplay = tiny_free_reattach_region(rack, tiny_depot_ptr, tiny);
-
- /* Fix up the metadata of the target magazine while the region is in the depot. */
- mag_ptr->mag_num_bytes_in_objects -= bytes_inplay;
- mag_ptr->num_bytes_in_magazine -= TINY_HEAP_SIZE;
- mag_ptr->mag_num_objects -= objects_in_use;
-
- /* Now we can drop the magazine lock of the source mag. */
- SZONE_MAGAZINE_PTR_UNLOCK(mag_ptr);
-
- tiny_depot_ptr->mag_num_bytes_in_objects += bytes_inplay;
- tiny_depot_ptr->num_bytes_in_magazine += TINY_HEAP_SIZE;
- tiny_depot_ptr->mag_num_objects -= objects_in_use;
-
- recirc_list_splice_last(rack, tiny_depot_ptr, REGION_TRAILER_FOR_TINY_REGION(tiny));
-
- /* Actually do the scan, done holding the depot lock, the call will drop the lock
- * around the actual madvise syscalls.
- */
- tiny_free_scan_madvise_free(rack, tiny_depot_ptr, tiny);
-
- /* Now the region is in the recirc depot, the next allocations to require more
- * blocks will come along and take one of these regions back out of the depot.
- * As OS X madvise's reuse on an per-region basis, we leave as many of these
- * regions in the depot as possible after memory pressure.
- */
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_depot_ptr);
- }
- }
-}
-#endif // CONFIG_MADVISE_PRESSURE_RELIEF
-
-static MALLOC_INLINE void
-tiny_madvise_free_range_no_lock(rack_t *rack,
- magazine_t *tiny_mag_ptr,
- region_t region,
- void *headptr,
- size_t headsize,
- void *ptr,
- msize_t msize)
-{
- region_trailer_t *node = REGION_TRAILER_FOR_TINY_REGION(region);
-
- // Lock on tiny_magazines[mag_index] is already held here
- // Calculate the first page in the coalesced block that would be safe to mark MADV_FREE
- size_t free_header_size = sizeof(tiny_free_list_t) + sizeof(msize_t);
- uintptr_t safe_ptr = (uintptr_t)ptr + free_header_size;
- uintptr_t round_safe = round_page_kernel(safe_ptr);
-
- // Calculate the last page in the coalesced block that would be safe to mark MADV_FREE
- size_t free_tail_size = sizeof(msize_t);
- uintptr_t safe_extent = (uintptr_t)ptr + TINY_BYTES_FOR_MSIZE(msize) - free_tail_size;
- uintptr_t trunc_extent = trunc_page_kernel(safe_extent);
-
- // The newly freed block may complete a span of bytes that cover a page. Mark it with MADV_FREE.
- if (round_safe < trunc_extent) { // Coalesced area covers a page (perhaps many)
- // Extend the freed block by the free region header and tail sizes to include pages
- // we may have coalesced that no longer host free region tails and headers.
- // This may extend over in-use ranges, but the MIN/MAX clamping below will fix that up.
- uintptr_t lo = trunc_page_kernel((uintptr_t)headptr - free_tail_size);
- uintptr_t hi = round_page_kernel((uintptr_t)headptr + headsize + free_header_size);
-
- uintptr_t free_lo = MAX(round_safe, lo);
- uintptr_t free_hi = MIN(trunc_extent, hi);
-
- if (free_lo < free_hi) {
- tiny_free_list_remove_ptr(rack, tiny_mag_ptr, ptr, msize);
- set_tiny_meta_header_in_use(ptr, msize);
-
- OSAtomicIncrement32Barrier(&(node->pinned_to_depot));
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- mvm_madvise_free(rack, region, free_lo, free_hi, &rack->last_madvise, rack->debug_flags & MALLOC_DO_SCRIBBLE);
- SZONE_MAGAZINE_PTR_LOCK(tiny_mag_ptr);
- OSAtomicDecrement32Barrier(&(node->pinned_to_depot));
-
- set_tiny_meta_header_free(ptr, msize);
- tiny_free_list_add_ptr(rack, tiny_mag_ptr, ptr, msize);
- }
- }
-}
-
-#if CONFIG_RECIRC_DEPOT
-static boolean_t
-tiny_get_region_from_depot(rack_t *rack, magazine_t *tiny_mag_ptr, mag_index_t mag_index, msize_t msize)
-{
- magazine_t *depot_ptr = &(rack->magazines[DEPOT_MAGAZINE_INDEX]);
-
-#if DEBUG_MALLOC
- if (DEPOT_MAGAZINE_INDEX == mag_index) {
- malloc_zone_error(rack->debug_flags, true, "tiny_get_region_from_depot called for magazine index -1\n");
- return 0;
- }
-#endif
-
- SZONE_MAGAZINE_PTR_LOCK(depot_ptr);
-
- // Appropriate a Depot'd region that can satisfy requested msize.
- region_trailer_t *node;
- region_t sparse_region;
- msize_t try_msize = msize;
-
- while (1) {
- sparse_region = tiny_find_msize_region(rack, depot_ptr, DEPOT_MAGAZINE_INDEX, try_msize);
- if (NULL == sparse_region) { // Depot empty?
- SZONE_MAGAZINE_PTR_UNLOCK(depot_ptr);
- return 0;
- }
-
- node = REGION_TRAILER_FOR_TINY_REGION(sparse_region);
- if (0 == node->pinned_to_depot) {
- // Found one!
- break;
- }
-
- // Try the next msize up - maybe the head of its free list will be in
- // a region we can use. Once we get the region we'll still allocate the
- // original msize.
- try_msize++;
-
- if (try_msize > NUM_TINY_SLOTS) {
- // Tried all the msizes but couldn't get a usable region. Let's
- // give up for now and we'll allocate a new region from the kernel.
- SZONE_MAGAZINE_PTR_UNLOCK(depot_ptr);
- return 0;
- }
- }
-
- // disconnect node from Depot
- recirc_list_extract(rack, depot_ptr, node);
-
- // Iterate the region pulling its free entries off the (locked) Depot's free list
- int objects_in_use = tiny_free_detach_region(rack, depot_ptr, sparse_region);
-
- // Transfer ownership of the region
- MAGAZINE_INDEX_FOR_TINY_REGION(sparse_region) = mag_index;
- MALLOC_ASSERT(node->pinned_to_depot == 0);
-
- // Iterate the region putting its free entries on its new (locked) magazine's free list
- size_t bytes_inplay = tiny_free_reattach_region(rack, tiny_mag_ptr, sparse_region);
-
- depot_ptr->mag_num_bytes_in_objects -= bytes_inplay;
- depot_ptr->num_bytes_in_magazine -= TINY_HEAP_SIZE;
- depot_ptr->mag_num_objects -= objects_in_use;
-
- tiny_mag_ptr->mag_num_bytes_in_objects += bytes_inplay;
- tiny_mag_ptr->num_bytes_in_magazine += TINY_HEAP_SIZE;
- tiny_mag_ptr->mag_num_objects += objects_in_use;
-
- // connect to magazine as last node
- recirc_list_splice_last(rack, tiny_mag_ptr, node);
-
- SZONE_MAGAZINE_PTR_UNLOCK(depot_ptr);
-
- // DTrace USDT Probe
- MAGMALLOC_DEPOTREGION(TINY_SZONE_FROM_RACK(rack), (int)mag_index, (void *)sparse_region,
- TINY_REGION_SIZE, (int)BYTES_USED_FOR_TINY_REGION(sparse_region));
-
- return 1;
-}
-
-static region_t
-tiny_free_try_depot_unmap_no_lock(rack_t *rack, magazine_t *depot_ptr, region_trailer_t *node)
-{
- if (0 < node->bytes_used || 0 < node->pinned_to_depot ||
- depot_ptr->recirculation_entries < recirc_retained_regions)
- {
- return NULL;
- }
-
- // disconnect node from Depot
- recirc_list_extract(rack, depot_ptr, node);
-
- // Iterate the region pulling its free entries off the (locked) Depot's free list
- region_t sparse_region = TINY_REGION_FOR_PTR(node);
- int objects_in_use = tiny_free_detach_region(rack, depot_ptr, sparse_region);
-
- if (0 == objects_in_use) {
- if (!rack_region_remove(rack, sparse_region, node)) {
- return NULL;
- }
- depot_ptr->num_bytes_in_magazine -= TINY_HEAP_SIZE;
-
- // Caller will transfer ownership of the region back to the OS with no locks held
- MAGMALLOC_DEALLOCREGION(TINY_SZONE_FROM_RACK(rack),
- (void *)sparse_region, TINY_REGION_SIZE); // DTrace USDT Probe
- return sparse_region;
- } else {
- malloc_zone_error(rack->debug_flags, true,
- "tiny_free_try_depot_unmap_no_lock objects_in_use not zero: %d\n",
- objects_in_use);
- return NULL;
- }
-}
-
-static boolean_t
-tiny_free_do_recirc_to_depot(rack_t *rack, magazine_t *tiny_mag_ptr, mag_index_t mag_index)
-{
- // The entire magazine crossed the "emptiness threshold". Transfer a region
- // from this magazine to the Depot. Choose a region that itself has crossed the emptiness threshold (i.e
- // is at least fraction "f" empty.) Such a region will be marked "suitable" on the recirculation list.
- // Start from the last node in order to keep the regions created earlier at the front of the list for
- // as long as possible. This helps reduce fragmentation.
- region_trailer_t *node = tiny_mag_ptr->lastNode;
-
- while (node && (!node->recirc_suitable || node->pinned_to_depot)) {
- // If we skip a node due to pinned_to_depot being non-zero, it must be
- // because another thread is madvising the same region in
- // tiny_madvise_free_range_no_lock(), called from tiny_free_no_lock().
- // When that's done, the same thread will enter tiny_free_try_recirc_to_depot()
- // for the same region, which will come back here. So this just defers
- // recirculation of the region.
- node = node->prev;
- }
-
- if (!node) {
-#if DEBUG_MALLOC
- malloc_report(ASL_LEVEL_INFO, "*** tiny_free_do_recirc_to_depot end of list\n");
-#endif
- return TRUE; // Caller must SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- }
-
- region_t sparse_region = TINY_REGION_FOR_PTR(node);
-
- // Deal with unclaimed memory -- mag_bytes_free_at_end or mag_bytes_free_at_start
- if (sparse_region == tiny_mag_ptr->mag_last_region &&
- (tiny_mag_ptr->mag_bytes_free_at_end || tiny_mag_ptr->mag_bytes_free_at_start)) {
- tiny_finalize_region(rack, tiny_mag_ptr);
- }
-
- // disconnect "suitable" node from magazine
- recirc_list_extract(rack, tiny_mag_ptr, node);
-
- // Iterate the region pulling its free entries off its (locked) magazine's free list
- int objects_in_use = tiny_free_detach_region(rack, tiny_mag_ptr, sparse_region);
- magazine_t *depot_ptr = &(rack->magazines[DEPOT_MAGAZINE_INDEX]);
-
- // hand over the region to the (locked) Depot
- SZONE_MAGAZINE_PTR_LOCK(depot_ptr);
- // this will cause tiny_free_list_add_ptr called by tiny_free_reattach_region to use
- // the depot as its target magazine, rather than magazine formerly associated with sparse_region
- MAGAZINE_INDEX_FOR_TINY_REGION(sparse_region) = DEPOT_MAGAZINE_INDEX;
- node->pinned_to_depot = 0;
-
- // Iterate the region putting its free entries on Depot's free list
- size_t bytes_inplay = tiny_free_reattach_region(rack, depot_ptr, sparse_region);
-
- tiny_mag_ptr->mag_num_bytes_in_objects -= bytes_inplay;
- tiny_mag_ptr->num_bytes_in_magazine -= TINY_HEAP_SIZE;
- tiny_mag_ptr->mag_num_objects -= objects_in_use;
-
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr); // Unlock the originating magazine
-
- depot_ptr->mag_num_bytes_in_objects += bytes_inplay;
- depot_ptr->num_bytes_in_magazine += TINY_HEAP_SIZE;
- depot_ptr->mag_num_objects += objects_in_use;
-
- // connect to Depot as last node
- recirc_list_splice_last(rack, depot_ptr, node);
-
- MAGMALLOC_RECIRCREGION(TINY_SZONE_FROM_RACK(rack), (int)mag_index, (void *)sparse_region, TINY_REGION_SIZE,
- (int)BYTES_USED_FOR_TINY_REGION(sparse_region)); // DTrace USDT Probe
-
-#if CONFIG_AGGRESSIVE_MADVISE
- if (!aggressive_madvise_enabled)
-#endif
- {
- // Mark free'd dirty pages with MADV_FREE to reduce memory pressure
- tiny_free_scan_madvise_free(rack, depot_ptr, sparse_region);
- }
-
- // If the region is entirely empty vm_deallocate() it outside the depot lock
- region_t r_dealloc = tiny_free_try_depot_unmap_no_lock(rack, depot_ptr, node);
- SZONE_MAGAZINE_PTR_UNLOCK(depot_ptr);
- if (r_dealloc) {
- mvm_deallocate_pages(r_dealloc, TINY_REGION_SIZE,
- MALLOC_FIX_GUARD_PAGE_FLAGS(rack->debug_flags));
- }
- return FALSE; // Caller need not unlock the originating magazine
-}
-
-static MALLOC_INLINE boolean_t
-tiny_free_try_recirc_to_depot(rack_t *rack,
- magazine_t *tiny_mag_ptr,
- mag_index_t mag_index,
- region_t region,
- void *headptr,
- size_t headsize,
- void *ptr,
- msize_t msize)
-{
- region_trailer_t *node = REGION_TRAILER_FOR_TINY_REGION(region);
- size_t bytes_used = node->bytes_used;
-
- if (DEPOT_MAGAZINE_INDEX != mag_index) {
- // Emptiness discriminant
- if (tiny_region_below_recirc_threshold(region)) {
- /* Region has crossed threshold from density to sparsity. Mark it "suitable" on the
- * recirculation candidates list. */
- node->recirc_suitable = TRUE;
- } else {
- /* After this free, we've found the region is still dense, so it must have been even more so before
- * the free. That implies the region is already correctly marked. Do nothing. */
- }
-
- // Has the entire magazine crossed the "emptiness threshold"? If so, transfer a region
- // from this magazine to the Depot. Choose a region that itself has crossed the emptiness threshold (i.e
- // is at least fraction "f" empty.) Such a region will be marked "suitable" on the recirculation list.
- if (tiny_magazine_below_recirc_threshold(tiny_mag_ptr)) {
- return tiny_free_do_recirc_to_depot(rack, tiny_mag_ptr, mag_index);
- }
- } else {
-#if CONFIG_AGGRESSIVE_MADVISE
- if (!aggressive_madvise_enabled)
-#endif
- {
- // We are free'ing into the depot, so madvise as we do so unless we were madvising every incoming
- // allocation anyway.
- tiny_madvise_free_range_no_lock(rack, tiny_mag_ptr, region, headptr, headsize, ptr, msize);
- }
-
- if (0 < bytes_used || 0 < node->pinned_to_depot) {
- /* Depot'd region is still live. Leave it in place on the Depot's recirculation list
- * so as to avoid thrashing between the Depot's free list and a magazines's free list
- * with detach_region/reattach_region */
- } else {
- /* Depot'd region is just now empty. Consider return to OS. */
- region_t r_dealloc = tiny_free_try_depot_unmap_no_lock(rack, tiny_mag_ptr, node);
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- if (r_dealloc) {
- mvm_deallocate_pages(r_dealloc, TINY_REGION_SIZE,
- MALLOC_FIX_GUARD_PAGE_FLAGS(rack->debug_flags));
- }
- return FALSE; // Caller need not unlock
- }
- }
- return TRUE; // Caller must do SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr)
-}
-#endif // CONFIG_RECIRC_DEPOT
-
-#define TINY_FREE_FLAG_PARTIAL 0x1
-#define TINY_FREE_FLAG_FROM_CACHE 0x2
-
-boolean_t
-tiny_free_no_lock(rack_t *rack, magazine_t *tiny_mag_ptr, mag_index_t mag_index,
- region_t region, void *ptr, msize_t msize, uint32_t flags)
-{
- void *original_ptr = ptr;
- size_t original_size = TINY_BYTES_FOR_MSIZE(msize);
- void *next_block = ((unsigned char *)ptr + original_size);
- msize_t previous_msize, next_msize;
- void *previous;
- tiny_free_list_t *big_free_block;
- tiny_free_list_t *after_next_block;
- tiny_free_list_t *before_next_block;
-
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "in tiny_free_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
- }
- if (!msize) {
- malloc_zone_error(rack->debug_flags, true,
- "trying to free tiny block that is too small in tiny_free_no_lock(), ptr=%p, msize=%d\n",
- ptr, msize);
- }
-#endif
-
- // Check that the region cookie is intact.
- region_check_cookie(region, ®ION_COOKIE_FOR_TINY_REGION(region));
-
- // 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_report(ASL_LEVEL_INFO, "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(rack, tiny_mag_ptr, previous, previous_msize);
-
- // zero out the trailing inline msize of the block to connect the zero
- // prefix of this block to the newly free block
- zero_tiny_free_inline_meta_following(previous, previous_msize);
-
- ptr = previous;
- msize += previous_msize;
- }
-
- // We try to coalesce with the next block
- if ((next_block < TINY_REGION_HEAP_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_report(ASL_LEVEL_INFO, "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 NUM_TINY_SLOTS and then adding ptr back
- // to slot NUM_TINY_SLOTS.
- if (next_msize > NUM_TINY_SLOTS) {
- msize += next_msize;
-
- big_free_block = (tiny_free_list_t *)next_block;
- after_next_block = free_list_unchecksum_ptr(rack, &big_free_block->next);
- before_next_block = free_list_unchecksum_ptr(rack, &big_free_block->previous);
-
- if (!before_next_block) {
- tiny_mag_ptr->mag_free_list[NUM_TINY_SLOTS].p = ptr;
- } else {
- before_next_block->next.u = free_list_checksum_ptr(rack, ptr);
- }
-
- if (after_next_block) {
- after_next_block->previous.u = free_list_checksum_ptr(rack, ptr);
- }
-
- // we don't need to checksum these since they are already checksummed
- ((tiny_free_list_t *)ptr)->previous = big_free_block->previous;
- ((tiny_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);
-
- // zero out inline metadata to continue the zero prefix of the
- // previous block - must happen before set_tiny_meta_header_free()
- // reinitializes the new inline metadata
- zero_tiny_free_inline_meta(big_free_block, next_msize);
-
- set_tiny_meta_header_free(ptr, msize);
-
- uint16_t next_block_index = TINY_INDEX_FOR_PTR(big_free_block) + 1;
- uint16_t ptr_index = TINY_INDEX_FOR_PTR(ptr) + 1;
- const grain_t slot = NUM_TINY_SLOTS;
- region_free_blocks_t *free_blocks = &((tiny_region_t)region)->free_blocks_by_slot[slot];
- if (free_blocks->first_block == next_block_index) {
- free_blocks->first_block = ptr_index;
- }
- if (free_blocks->last_block == next_block_index) {
- free_blocks->last_block = ptr_index;
- }
- goto tiny_free_ending;
- }
- tiny_free_list_remove_ptr(rack, tiny_mag_ptr, next_block, next_msize);
- set_tiny_meta_header_middle(next_block); // clear the meta_header to enable coalescing backwards
- // zero out inline metadata to continue the zero prefix of the previous
- // block
- zero_tiny_free_inline_meta(next_block, next_msize);
- msize += next_msize;
- }
-
- if (malloc_zero_policy != MALLOC_ZERO_ON_FREE) {
- // The tiny cache already scribbles free blocks as they go through the
- // cache, so we do not need to do it here.
- //
- // XXX This should probably also be conditional on CONFIG_TINY_CACHE
- if ((rack->debug_flags & MALLOC_DO_SCRIBBLE) &&
- !(flags & TINY_FREE_FLAG_FROM_CACHE)) {
- memset(ptr, SCRABBLE_BYTE, TINY_BYTES_FOR_MSIZE(msize));
- }
- }
-
- tiny_free_list_add_ptr(rack, tiny_mag_ptr, ptr, msize);
-
-tiny_free_ending:
- // we use original_size and not msize to avoid double counting the coalesced blocks
- tiny_mag_ptr->mag_num_bytes_in_objects -= original_size;
-
- // Update this region's bytes in use count
- region_trailer_t *trailer = REGION_TRAILER_FOR_TINY_REGION(region);
- size_t bytes_used = trailer->bytes_used - original_size;
- trailer->bytes_used = (unsigned int)bytes_used;
-
- // Partial free accounts for the case where we allocate a block for
- // posix_memalign and then free some range of bytes at the start and/or
- // the end. In that case, we aren't changing the number of allocated objects.
- // Similarly for realloc() in the case where we shrink in place.
- if (!(flags & TINY_FREE_FLAG_PARTIAL)) {
- trailer->objects_in_use--;
- tiny_mag_ptr->mag_num_objects--;
- }
-#if CONFIG_AGGRESSIVE_MADVISE
- if (aggressive_madvise_enabled) {
- // Platforms that want to madvise every freed allocation do so here, even if we continue
- // on to use the recirc depot after.
- tiny_madvise_free_range_no_lock(rack, tiny_mag_ptr, region, original_ptr, original_size, ptr, msize);
- }
-#endif
-
- // Caller must do SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr) if this function
- // returns TRUE.
- boolean_t needs_unlock = TRUE;
-
-#if CONFIG_RECIRC_DEPOT
- needs_unlock = tiny_free_try_recirc_to_depot(rack, tiny_mag_ptr, mag_index, region, original_ptr, original_size, ptr, msize);
-#endif // CONFIG_RECIRC_DEPOT
- return needs_unlock;
-}
-
-// Allocates from the last region or a freshly allocated region
-static void *
-tiny_malloc_from_region_no_lock(rack_t *rack,
- magazine_t *tiny_mag_ptr,
- mag_index_t mag_index,
- msize_t msize,
- void *aligned_address)
-{
- void *ptr;
-
- // Deal with unclaimed memory -- mag_bytes_free_at_end or mag_bytes_free_at_start
- if (tiny_mag_ptr->mag_bytes_free_at_end || tiny_mag_ptr->mag_bytes_free_at_start) {
- tiny_finalize_region(rack, tiny_mag_ptr);
- }
-
- tiny_region_t region = (tiny_region_t)aligned_address;
-
- // We set the unused bits of the header in the last pair to be all ones, and those of the inuse to zeroes.
-#if NUM_TINY_BLOCKS & 31
- const uint32_t header = 0xFFFFFFFFU << (NUM_TINY_BLOCKS & 31);
-#else
- const uint32_t header = 0;
-#endif
- region->pairs[CEIL_NUM_TINY_BLOCKS_WORDS - 1].header = header;
- region->pairs[CEIL_NUM_TINY_BLOCKS_WORDS - 1].inuse = 0;
-
- // Tag the region at "aligned_address" as belonging to us,
- // and so put it under the protection of the magazine lock we are holding.
- // Do this before advertising "aligned_address" on the hash ring(!)
- MAGAZINE_INDEX_FOR_TINY_REGION(region) = mag_index;
-
- // Insert the new region into the hash ring
- rack_region_insert(rack, region);
-
- tiny_mag_ptr->mag_last_region = region;
- BYTES_USED_FOR_TINY_REGION(region) = TINY_BYTES_FOR_MSIZE(msize);
- OBJECTS_IN_USE_FOR_TINY_REGION(region) = 1;
-
-#if CONFIG_ASLR_INTERNAL
- int offset_msize = malloc_entropy[0] & TINY_ENTROPY_MASK;
-#if DEBUG_MALLOC
- if (getenv("MallocASLRForce")) {
- offset_msize = strtol(getenv("MallocASLRForce"), NULL, 0) & TINY_ENTROPY_MASK;
- }
- if (getenv("MallocASLRPrint")) {
- malloc_report(ASL_LEVEL_INFO, "Region: %p offset: %d\n", region, offset_msize);
- }
-#endif
-#else
- int offset_msize = 0;
-#endif
- ptr = (void *)(TINY_REGION_HEAP_BASE(region) + TINY_BYTES_FOR_MSIZE(offset_msize));
- set_tiny_meta_header_in_use(ptr, msize);
- tiny_mag_ptr->mag_num_objects++;
- tiny_mag_ptr->mag_num_bytes_in_objects += TINY_BYTES_FOR_MSIZE(msize);
- tiny_mag_ptr->num_bytes_in_magazine += TINY_HEAP_SIZE;
-
- // We put a header on the last block so that it appears in use (for coalescing, etc...)
- set_tiny_meta_header_in_use_1((void *)((uintptr_t)ptr + TINY_BYTES_FOR_MSIZE(msize)));
- tiny_mag_ptr->mag_bytes_free_at_end = TINY_BYTES_FOR_MSIZE(NUM_TINY_BLOCKS - msize - offset_msize);
-
-#if CONFIG_ASLR_INTERNAL
- // Put a header on the previous block for same reason
- tiny_mag_ptr->mag_bytes_free_at_start = TINY_BYTES_FOR_MSIZE(offset_msize);
- if (offset_msize) {
- set_tiny_meta_header_in_use_1((void *)((uintptr_t)ptr - TINY_QUANTUM));
- }
-#else
- tiny_mag_ptr->mag_bytes_free_at_start = 0;
-#endif
-
- // connect to magazine as last node
- recirc_list_splice_last(rack, tiny_mag_ptr, REGION_TRAILER_FOR_TINY_REGION(region));
-
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "in tiny_malloc_from_region_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
- }
-#endif
- return ptr;
-}
-
-void *
-tiny_memalign(szone_t *szone, size_t alignment, size_t size, size_t span)
-{
- msize_t mspan = TINY_MSIZE_FOR_BYTES(span + TINY_QUANTUM - 1);
- void *p = tiny_malloc_should_clear(&szone->tiny_rack, mspan, 0);
-
- if (NULL == p) {
- return NULL;
- }
-
- size_t offset = ((uintptr_t)p) & (alignment - 1); // p % alignment
- size_t pad = (0 == offset) ? 0 : alignment - offset; // p + pad achieves desired alignment
-
- msize_t msize = TINY_MSIZE_FOR_BYTES(size + TINY_QUANTUM - 1);
- msize_t mpad = TINY_MSIZE_FOR_BYTES(pad + TINY_QUANTUM - 1);
- msize_t mwaste = mspan - msize - mpad; // excess blocks
-
- if (mpad > 0) {
- void *q = (void *)(((uintptr_t)p) + pad);
-
- // Mark q as a block header and in-use, thus creating two blocks.
- magazine_t *tiny_mag_ptr = mag_lock_zine_for_region_trailer(szone->tiny_rack.magazines,
- REGION_TRAILER_FOR_TINY_REGION(TINY_REGION_FOR_PTR(p)),
- MAGAZINE_INDEX_FOR_TINY_REGION(TINY_REGION_FOR_PTR(p)));
- set_tiny_meta_header_in_use(q, msize);
- tiny_mag_ptr->mag_num_objects++;
-
- // set_tiny_meta_header_in_use() "reaffirms" the block_header on the *following* block, so
- // now set its in_use bit as well. But only if its within the original allocation made above.
- if (mwaste > 0) {
- BITARRAY_SET(TINY_INUSE_FOR_HEADER(TINY_BLOCK_HEADER_FOR_PTR(q)), TINY_INDEX_FOR_PTR(q) + msize);
- }
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
-
- // Give up mpad blocks beginning at p to the tiny free list
- free_tiny(&szone->tiny_rack, p, TINY_REGION_FOR_PTR(p), TINY_BYTES_FOR_MSIZE(mpad), true);
-
- p = q; // advance p to the desired alignment
- }
-
- if (mwaste > 0) {
- void *q = (void *)(((uintptr_t)p) + TINY_BYTES_FOR_MSIZE(msize));
- // Mark q as block header and in-use, thus creating two blocks.
- magazine_t *tiny_mag_ptr = mag_lock_zine_for_region_trailer(szone->tiny_rack.magazines,
- REGION_TRAILER_FOR_TINY_REGION(TINY_REGION_FOR_PTR(p)),
- MAGAZINE_INDEX_FOR_TINY_REGION(TINY_REGION_FOR_PTR(p)));
- set_tiny_meta_header_in_use(q, mwaste);
- tiny_mag_ptr->mag_num_objects++;
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
-
- // Give up mwaste blocks beginning at q to the tiny free list
- free_tiny(&szone->tiny_rack, q, TINY_REGION_FOR_PTR(q), TINY_BYTES_FOR_MSIZE(mwaste), true);
- }
-
- return p; // p has the desired size and alignment, and can later be free()'d
-}
-
-boolean_t
-tiny_claimed_address(rack_t *rack, void *ptr)
-{
- region_t r = tiny_region_for_ptr_no_lock(rack, ptr);
- return r && ptr >= TINY_REGION_HEAP_BASE(r)
- && ptr < TINY_REGION_HEAP_END(r);
-}
-
-void *
-tiny_try_shrink_in_place(rack_t *rack, void *ptr, size_t old_size, size_t new_good_size)
-{
- msize_t new_msize = TINY_MSIZE_FOR_BYTES(new_good_size);
- msize_t mshrinkage = TINY_MSIZE_FOR_BYTES(old_size) - new_msize;
-
- if (mshrinkage) {
- void *q = (void *)((uintptr_t)ptr + TINY_BYTES_FOR_MSIZE(new_msize));
- magazine_t *tiny_mag_ptr = mag_lock_zine_for_region_trailer(rack->magazines,
- REGION_TRAILER_FOR_TINY_REGION(TINY_REGION_FOR_PTR(ptr)),
- MAGAZINE_INDEX_FOR_TINY_REGION(TINY_REGION_FOR_PTR(ptr)));
-
- // Mark q as block header and in-use, thus creating two blocks.
- set_tiny_meta_header_in_use(q, mshrinkage);
- tiny_mag_ptr->mag_num_objects++;
-
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- free_tiny(rack, q, TINY_REGION_FOR_PTR(q), 0, true);
- }
- return ptr;
-}
-
-boolean_t
-tiny_try_realloc_in_place(rack_t *rack, 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, new_msize;
- void *leftover;
- region_trailer_t *trailer = REGION_TRAILER_FOR_TINY_REGION(TINY_REGION_FOR_PTR(ptr));
-
- index = TINY_INDEX_FOR_PTR(ptr);
- old_msize = TINY_MSIZE_FOR_BYTES(old_size);
- new_msize = TINY_MSIZE_FOR_BYTES(new_size + TINY_QUANTUM - 1);
- next_index = index + old_msize;
-
- if (next_index >= NUM_TINY_BLOCKS) {
- return 0;
- }
- next_block = (char *)ptr + old_size;
-
- magazine_t *tiny_mag_ptr = mag_lock_zine_for_region_trailer(rack->magazines,
- trailer,
- MAGAZINE_INDEX_FOR_TINY_REGION(TINY_REGION_FOR_PTR(ptr)));
-
- if (DEPOT_MAGAZINE_INDEX == MAGAZINE_INDEX_FOR_TINY_REGION(TINY_REGION_FOR_PTR(ptr))) {
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- return 0;
- }
-
- coalesced_msize = new_msize - old_msize;
-#if CONFIG_TINY_CACHE
- void *last_free_ptr = tiny_mag_ptr->mag_last_free;
- msize_t last_free_msize = tiny_mag_ptr->mag_last_free_msize;
- if (last_free_ptr == next_block && old_msize + last_free_msize >= new_msize) {
- /*
- * There is a block in mag_last_free and it's immediately after
- * this block and it's large enough. We can use some or all of it.
- */
- leftover_msize = last_free_msize - coalesced_msize;
- if (leftover_msize) {
- tiny_mag_ptr->mag_last_free_msize -= coalesced_msize;
- tiny_mag_ptr->mag_last_free += new_size - old_size;
- // The block in mag_last_free is still marked as header and in-use, so copy that
- // state to the block that remains. The state for the block that we're going to
- // use is adjusted by the set_tiny_meta_header_middle() call below.
- void *leftover_ptr = ((char *)next_block) + TINY_BYTES_FOR_MSIZE(coalesced_msize);
- set_tiny_meta_header_in_use(leftover_ptr, leftover_msize);
- } else {
- // Using the whole block.
- tiny_mag_ptr->mag_last_free = NULL;
- tiny_mag_ptr->mag_last_free_msize = 0;
- tiny_mag_ptr->mag_last_free_rgn = NULL;
- trailer->objects_in_use--;
- }
- set_tiny_meta_header_middle(next_block);
- tiny_check_zero_or_clear(last_free_ptr, coalesced_msize, false);
- coalesced_msize = 0; // No net change in memory use
- } else {
-#endif // CONFIG_TINY_CACHE
- /*
- * Try to expand into unused space immediately after this block.
- */
- msize_t unused_msize = TINY_MSIZE_FOR_BYTES(tiny_mag_ptr->mag_bytes_free_at_end);
- void *unused_start = TINY_REGION_HEAP_END(TINY_REGION_FOR_PTR(ptr)) - tiny_mag_ptr->mag_bytes_free_at_end;
- if (tiny_mag_ptr->mag_last_region == TINY_REGION_FOR_PTR(ptr)
- && coalesced_msize < unused_msize && unused_start == ptr + old_size) {
- // The block at the start of mag_bytes_free_at_end is marked as
- // header/in-use and the next one has header/free. We need to
- // reset both the header and in-use bit in the first block and we
- // need to reset the header bit in the second block if it's part of
- // the new allocation.
- set_tiny_meta_header_middle(unused_start);
- if (coalesced_msize > 1) {
- set_tiny_meta_header_middle(unused_start + TINY_QUANTUM);
- }
- tiny_mag_ptr->mag_bytes_free_at_end -= TINY_BYTES_FOR_MSIZE(coalesced_msize);
- if (tiny_mag_ptr->mag_bytes_free_at_end) {
- // Mark the first block of the remaining free area as a header and in-use.
- set_tiny_meta_header_in_use_1(ptr + TINY_BYTES_FOR_MSIZE(new_msize));
- }
- tiny_check_zero_or_clear(unused_start, coalesced_msize, false);
- } else {
- /*
- * Look for a free block immediately afterwards. If it's large
- * enough, we can consume (part of) it.
- */
- is_free = tiny_meta_header_is_free(next_block);
- if (!is_free) {
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- return 0; // next_block is in use;
- }
- next_msize = get_tiny_free_size(next_block);
- if (old_msize + next_msize < new_msize) {
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- return 0; // even with next block, not enough
- }
- /*
- * The following block is big enough; pull it from its freelist and chop off enough to satisfy
- * our needs.
- */
- tiny_free_list_remove_ptr(rack, tiny_mag_ptr, next_block, next_msize);
- set_tiny_meta_header_middle(next_block); // clear the meta_header to enable coalescing backwards
-
- tiny_check_and_zero_inline_meta_from_freelist(rack, next_block, next_msize);
- tiny_check_zero_or_clear(next_block, coalesced_msize, false);
-
- leftover_msize = next_msize - coalesced_msize;
- if (leftover_msize) {
- /* there's some left, so put the remainder back */
- leftover = (void *)((uintptr_t)next_block + TINY_BYTES_FOR_MSIZE(coalesced_msize));
- tiny_free_list_add_ptr(rack, tiny_mag_ptr, leftover, leftover_msize);
- }
- set_tiny_meta_header_in_use(ptr, old_msize + coalesced_msize);
- }
-#if CONFIG_TINY_CACHE
- }
-#endif // CONFIG_TINY_CACHE
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "in tiny_try_realloc_in_place(), ptr=%p, msize=%d\n", ptr, old_msize + coalesced_msize);
- }
-#endif
- tiny_mag_ptr->mag_num_bytes_in_objects += TINY_BYTES_FOR_MSIZE(coalesced_msize);
-
- // Update this region's bytes in use count
- region_trailer_t *node = REGION_TRAILER_FOR_TINY_REGION(TINY_REGION_FOR_PTR(ptr));
- size_t bytes_used = node->bytes_used + TINY_BYTES_FOR_MSIZE(coalesced_msize);
- node->bytes_used = (unsigned int)bytes_used;
-
- // Emptiness discriminant
- if (bytes_used < DENSITY_THRESHOLD(TINY_HEAP_SIZE)) {
- /* After this reallocation the region is still sparse, so it must have been even more so before
- * the reallocation. That implies the region is already correctly marked. Do nothing. */
- } else {
- /* Region has crossed threshold from sparsity to density. Mark it not "suitable" on the
- * recirculation candidates list. */
- node->recirc_suitable = FALSE;
- }
-
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- CHECK(szone, __PRETTY_FUNCTION__);
- return 1;
-}
-
-static char *tiny_check_fail_msg = "*** check: incorrect tiny region ";
-
-#define TINY_CHECK_FAIL(fmt, ...) \
- malloc_zone_check_fail(tiny_check_fail_msg, \
- "%ld, counter=%d\n" fmt, region_index, counter, __VA_ARGS__);
-
-boolean_t
-tiny_check_region(rack_t *rack, region_t region, size_t region_index,
- unsigned counter)
-{
- uintptr_t start, ptr, region_end;
- boolean_t prev_free = 0;
- boolean_t is_free;
- msize_t msize;
- tiny_free_list_t *free_head;
- void *follower, *previous, *next;
- mag_index_t mag_index = MAGAZINE_INDEX_FOR_TINY_REGION(region);
- magazine_t *tiny_mag_ptr = &(rack->magazines[mag_index]);
-
- // Assumes locked
- CHECK_MAGAZINE_PTR_LOCKED(szone, tiny_mag_ptr, __PRETTY_FUNCTION__);
-
- // Do not check the region if pinned_to_depot is not zero because it
- // may not be in a consistent state (specifically, if may have a
- // block marked as in-use that's longer than any legal allocation,
- // which upsets get_tiny_meta_header() because it can't determine the
- // block's length).
- if (!REGION_TRAILER_FOR_TINY_REGION(region)->pinned_to_depot) {
- return 1;
- }
-
- /* establish region limits */
- start = (uintptr_t)TINY_REGION_HEAP_BASE(region);
- ptr = start;
- if (region == tiny_mag_ptr->mag_last_region) {
- ptr += tiny_mag_ptr->mag_bytes_free_at_start;
-
- /*
- * Check the leading block's integrity here also.
- */
- if (tiny_mag_ptr->mag_bytes_free_at_start) {
- msize = get_tiny_meta_header((void *)(ptr - TINY_QUANTUM), &is_free);
- if (is_free || (msize != 1)) {
- TINY_CHECK_FAIL("*** invariant broken for leader block %p - %d %d\n",
- (void *)(ptr - TINY_QUANTUM), msize, is_free);
- return 0;
- }
- }
- }
- region_end = (uintptr_t)TINY_REGION_HEAP_END(region);
-
- /*
- * The last region may have a trailing chunk which has not been converted into inuse/freelist
- * blocks yet.
- */
- if (region == tiny_mag_ptr->mag_last_region) {
- region_end -= tiny_mag_ptr->mag_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) {
- TINY_CHECK_FAIL("*** invariant broken for tiny block %p this msize=%d - size is too small\n", (void *)ptr, msize);
- return 0;
- }
-
- if (!is_free) {
- /*
- * In use blocks cannot be more than NUM_TINY_SLOTS quanta large.
- */
- prev_free = 0;
- if (msize > NUM_TINY_SLOTS) {
- TINY_CHECK_FAIL("*** invariant broken for %p this tiny msize=%d - size is too large\n", (void *)ptr, msize);
- return 0;
- }
- /* move to next block */
- ptr += TINY_BYTES_FOR_MSIZE(msize);
- } else {
-#if !CONFIG_RELAXED_INVARIANT_CHECKS
- /*
- * Free blocks must have been coalesced, we cannot have a free block following another
- * free block.
- */
- if (prev_free) {
- TINY_CHECK_FAIL("*** invariant broken for free block %p this tiny msize=%d: two free blocks in a row\n", (void *)ptr, msize);
- return 0;
- }
-#endif // CONFIG_RELAXED_INVARIANT_CHECKS
- prev_free = 1;
- /*
- * Check the integrity of this block's entry in its freelist.
- */
- free_head = (tiny_free_list_t *)ptr;
- previous = free_list_unchecksum_ptr(rack, &free_head->previous);
- next = free_list_unchecksum_ptr(rack, &free_head->next);
- if (previous && !tiny_meta_header_is_free(previous)) {
- TINY_CHECK_FAIL("*** invariant broken for %p (previous %p is not a free pointer)\n", (void *)ptr, previous);
- return 0;
- }
- if (next && !tiny_meta_header_is_free(next)) {
- TINY_CHECK_FAIL("*** invariant broken for %p (next in free list %p is not a free pointer)\n", (void *)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)) {
- TINY_CHECK_FAIL("*** invariant broken for tiny free %p followed by %p in region %p [%p-%p] "
- "(end marker incorrect) should be %d; in fact %d\n",
- (void *)ptr, follower, region, TINY_REGION_HEAP_BASE(region), (void *)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) {
- TINY_CHECK_FAIL("*** invariant broken for region end %p - %p\n", (void *)ptr, (void *)region_end);
- return 0;
- }
- /*
- * Check the trailing block's integrity.
- */
- if (region == tiny_mag_ptr->mag_last_region) {
- if (tiny_mag_ptr->mag_bytes_free_at_end) {
- msize = get_tiny_meta_header((void *)ptr, &is_free);
- if (is_free || (msize != 1)) {
- TINY_CHECK_FAIL("*** invariant broken for blocker block %p - %d %d\n", (void *)ptr, msize, is_free);
- return 0;
- }
- }
- }
- return 1;
-}
-
-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;
- 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;
- uint32_t *block_header;
- uint32_t *in_use;
- unsigned block_index;
- unsigned block_limit;
- boolean_t is_free;
- msize_t msize;
- void *mapped_ptr;
- unsigned bit;
- magazine_t *tiny_mag_base = NULL;
-
- region_hash_generation_t *trg_ptr;
- err = reader(task, (vm_address_t)szone->tiny_rack.region_generation, sizeof(region_hash_generation_t), (void **)&trg_ptr);
- if (err) {
- return err;
- }
-
- num_regions = trg_ptr->num_regions_allocated;
- err = reader(task, (vm_address_t)trg_ptr->hashed_regions, sizeof(region_t) * num_regions, (void **)®ions);
- if (err) {
- return err;
- }
-
- if (type_mask & MALLOC_PTR_IN_USE_RANGE_TYPE) {
- // Map in all active magazines. Do this outside the iteration over regions.
- err = reader(task, (vm_address_t)(szone->tiny_rack.magazines), szone->tiny_rack.num_magazines * sizeof(magazine_t),
- (void **)&tiny_mag_base);
- if (err) {
- return err;
- }
- }
-
- for (index = 0; index < num_regions; ++index) {
- region = regions[index];
- if (HASHRING_OPEN_ENTRY != region && HASHRING_REGION_DEALLOCATED != region) {
- range.address = (vm_address_t)TINY_REGION_HEAP_BASE(region);
- range.size = (vm_size_t)TINY_HEAP_SIZE;
- if (type_mask & MALLOC_ADMIN_REGION_RANGE_TYPE) {
- admin_range.address = TINY_REGION_METADATA(region);
- admin_range.size = TINY_METADATA_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 = TINY_HEAP_SIZE;
- recorder(task, context, MALLOC_PTR_REGION_RANGE_TYPE, &ptr_range, 1);
- }
- if (type_mask & MALLOC_PTR_IN_USE_RANGE_TYPE) {
- err = reader(task, (vm_address_t)region, (vm_size_t)TINY_REGION_SIZE, (void **)&mapped_region);
- if (err) {
- return err;
- }
-
- mag_index_t mag_index = MAGAZINE_INDEX_FOR_TINY_REGION(mapped_region);
- magazine_t *tiny_mag_ptr = tiny_mag_base + mag_index;
-
- int cached_free_blocks = 0;
-#if CONFIG_TINY_CACHE
- // Each magazine could have a pointer to a cached free block from
- // this region. Count the regions that have such a pointer.
- for (mag_index = 0; mag_index < szone->tiny_rack.num_magazines; mag_index++) {
- if (region == (tiny_mag_base + mag_index)->mag_last_free_rgn) {
- cached_free_blocks++;
- }
- }
-#endif // CONFIG_TINY_CACHE
-
- block_header = TINY_BLOCK_HEADER_FOR_REGION(mapped_region);
- in_use = TINY_INUSE_FOR_HEADER(block_header);
- block_index = 0;
- block_limit = NUM_TINY_BLOCKS;
- if (region == tiny_mag_ptr->mag_last_region) {
- block_index += TINY_MSIZE_FOR_BYTES(tiny_mag_ptr->mag_bytes_free_at_start);
- block_limit -= TINY_MSIZE_FOR_BYTES(tiny_mag_ptr->mag_bytes_free_at_end);
- }
-
- for (; block_index < block_limit; block_index += msize) {
- vm_size_t block_offset = TINY_BYTES_FOR_MSIZE(block_index);
- is_free = !BITARRAY_BIT(in_use, block_index);
- if (is_free) {
- mapped_ptr = TINY_REGION_HEAP_BASE(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;
- }
- } else {
-#if CONFIG_TINY_CACHE
- // If there are still magazines that have cached free
- // blocks in this region, check whether this is one of
- // them and don't return the block pointer if it is.
- void *ptr = TINY_REGION_HEAP_BASE(region) + block_offset;
- boolean_t block_cached = false;
- if (cached_free_blocks) {
- for (mag_index = 0; mag_index < szone->tiny_rack.num_magazines; mag_index++) {
- if (ptr == (tiny_mag_base + mag_index)->mag_last_free) {
- block_cached = true;
- cached_free_blocks--;
- msize = (tiny_mag_base + mag_index)->mag_last_free_msize;
- break;
- }
- }
- }
- if (block_cached) {
- if (!msize) {
- return KERN_FAILURE; // Somethings amiss. Avoid looping at this block_index.
- }
- continue;
- }
-#endif // CONFIG_TINY_CACHE
- msize = 1;
- bit = block_index + 1;
- while (!BITARRAY_BIT(block_header, bit)) {
- bit++;
- msize++;
- }
- buffer[count].address = (vm_address_t)TINY_REGION_HEAP_BASE(region) + 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;
- }
- }
-
- if (!msize) {
- return KERN_FAILURE; // Somethings amiss. Avoid looping at this block_index.
- }
- }
- if (count) {
- recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE, buffer, count);
- count = 0;
- }
- }
- }
- }
- return 0;
-}
-
-void *
-tiny_malloc_from_free_list(rack_t *rack, magazine_t *tiny_mag_ptr, mag_index_t mag_index, msize_t msize)
-{
- tiny_free_list_t *ptr;
- msize_t this_msize;
- grain_t slot = tiny_slot_from_msize(msize);
- free_list_t *free_list = tiny_mag_ptr->mag_free_list;
- free_list_t *the_slot = free_list + slot;
- tiny_free_list_t *next;
- free_list_t *limit;
-#if defined(__LP64__)
- uint64_t bitmap;
-#else
- uint32_t bitmap;
-#endif
- msize_t leftover_msize;
- tiny_free_list_t *leftover_ptr;
-
- // Assumes we've locked the region
- CHECK_MAGAZINE_PTR_LOCKED(szone, tiny_mag_ptr, __PRETTY_FUNCTION__);
-
- // Look for an exact match by checking the freelist for this msize.
- //
- ptr = the_slot->p;
- if (ptr) {
- next = free_list_unchecksum_ptr(rack, &ptr->next);
- if (next) {
- next->previous = ptr->previous;
- } else {
- BITMAPV_CLR(tiny_mag_ptr->mag_bitmap, slot);
- }
- the_slot->p = next;
- this_msize = msize;
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "in tiny_malloc_from_free_list(), exact match ptr=%p, this_msize=%d\n", ptr, this_msize);
- }
-#endif
- tiny_update_region_free_list_for_remove(slot, ptr, next);
- tiny_check_and_zero_inline_meta_from_freelist(rack, ptr, msize);
-
- 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.
-#if defined(__LP64__)
- bitmap = ((uint64_t *)(tiny_mag_ptr->mag_bitmap))[0] & ~((1ULL << slot) - 1);
-#else
- bitmap = tiny_mag_ptr->mag_bitmap[0] & ~((1 << slot) - 1);
-#endif
- if (!bitmap) {
- goto try_tiny_malloc_from_end;
- }
-
- slot = BITMAPV_CTZ(bitmap);
- limit = free_list + NUM_TINY_SLOTS;
- free_list += slot;
-
- if (free_list < limit) {
- ptr = free_list->p;
- if (ptr) {
- next = free_list_unchecksum_ptr(rack, &ptr->next);
- free_list->p = next;
- if (next) {
- next->previous = ptr->previous;
- } else {
- BITMAPV_CLR(tiny_mag_ptr->mag_bitmap, slot);
- }
- this_msize = get_tiny_free_size(ptr);
- if (os_unlikely(this_msize < msize)) {
- malloc_zone_error(MALLOC_ABORT_ON_CORRUPTION, true,
- "Corruption of tiny freelist %p: size too small (%u/%u)\n",
- ptr, this_msize, msize);
-
- }
- tiny_update_region_free_list_for_remove(slot, ptr, next);
- tiny_check_and_zero_inline_meta_from_freelist(rack, ptr, this_msize);
- goto add_leftover_and_proceed;
- }
-#if DEBUG_MALLOC
- malloc_report(ASL_LEVEL_ERR, "in tiny_malloc_from_free_list(), mag_bitmap out of sync, slot=%d\n", slot);
-#endif
- }
-
- // We are now looking at the last slot, which contains blocks equal to, or
- // due to coalescing of free blocks, larger than NUM_TINY_SLOTS * 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->p;
- if (ptr) {
- this_msize = get_tiny_free_size(ptr);
- if (os_unlikely(this_msize < msize)) {
- malloc_zone_error(MALLOC_ABORT_ON_CORRUPTION, true,
- "Corruption of tiny freelist %p: size too small (%u/%u)\n",
- ptr, this_msize, msize);
- }
- next = free_list_unchecksum_ptr(rack, &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 = (tiny_free_list_t *)((unsigned char *)ptr + TINY_BYTES_FOR_MSIZE(msize));
-
- tiny_free_list_t tmp_ptr = *ptr;
- tiny_check_and_zero_inline_meta_from_freelist(rack, ptr, this_msize);
-
- limit->p = leftover_ptr;
- if (next) {
- next->previous.u = free_list_checksum_ptr(rack, leftover_ptr);
- }
- leftover_ptr->previous = tmp_ptr.previous;
- leftover_ptr->next = tmp_ptr.next;
- set_tiny_meta_header_free(leftover_ptr, leftover_msize);
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO,
- "in tiny_malloc_from_free_list(), last slot ptr=%p, msize=%d this_msize=%d\n", ptr, msize, this_msize);
- }
-#endif
- this_msize = msize;
- tiny_update_region_free_list_for_remove(NUM_TINY_SLOTS, ptr, leftover_ptr);
-
- goto return_tiny_alloc;
- }
- if (next) {
- next->previous = ptr->previous;
- }
- limit->p = next;
- tiny_update_region_free_list_for_remove(slot, ptr, next);
- tiny_check_and_zero_inline_meta_from_freelist(rack, ptr, this_msize);
- goto add_leftover_and_proceed;
- /* NOTREACHED */
- }
-
-try_tiny_malloc_from_end:
- // Let's see if we can use tiny_mag_ptr->mag_bytes_free_at_end
- if (tiny_mag_ptr->mag_bytes_free_at_end >= TINY_BYTES_FOR_MSIZE(msize)) {
- ptr = (tiny_free_list_t *)((uintptr_t)TINY_REGION_HEAP_END(tiny_mag_ptr->mag_last_region) - tiny_mag_ptr->mag_bytes_free_at_end);
- tiny_mag_ptr->mag_bytes_free_at_end -= TINY_BYTES_FOR_MSIZE(msize);
- if (tiny_mag_ptr->mag_bytes_free_at_end) {
- // let's add an in use block after ptr to serve as boundary
- set_tiny_meta_header_in_use_1((unsigned char *)ptr + TINY_BYTES_FOR_MSIZE(msize));
- }
- this_msize = msize;
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "in tiny_malloc_from_free_list(), from end ptr=%p, msize=%d\n", ptr, msize);
- }
-#endif
- goto return_tiny_alloc;
- }
-#if CONFIG_ASLR_INTERNAL
- // Try from start if nothing left at end
- if (tiny_mag_ptr->mag_bytes_free_at_start >= TINY_BYTES_FOR_MSIZE(msize)) {
- ptr = (tiny_free_list_t *)(TINY_REGION_HEAP_BASE(tiny_mag_ptr->mag_last_region) + tiny_mag_ptr->mag_bytes_free_at_start -
- TINY_BYTES_FOR_MSIZE(msize));
- tiny_mag_ptr->mag_bytes_free_at_start -= TINY_BYTES_FOR_MSIZE(msize);
- if (tiny_mag_ptr->mag_bytes_free_at_start) {
- // let's add an in use block before ptr to serve as boundary
- set_tiny_meta_header_in_use_1((unsigned char *)ptr - TINY_QUANTUM);
- }
- this_msize = msize;
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "in tiny_malloc_from_free_list(), from start ptr=%p, msize=%d\n", ptr, msize);
- }
-#endif
- goto return_tiny_alloc;
- }
-#endif
- return NULL;
-
-add_leftover_and_proceed:
- if (!this_msize || (this_msize > msize)) {
- // XXX This works even when (this_msize == 0) because the unsigned
- // subtraction wraps around to the correct result
- leftover_msize = this_msize - msize;
- leftover_ptr = (tiny_free_list_t *)((unsigned char *)ptr + TINY_BYTES_FOR_MSIZE(msize));
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "in tiny_malloc_from_free_list(), adding leftover ptr=%p, this_msize=%d\n", ptr, this_msize);
- }
-#endif
- tiny_free_list_add_ptr(rack, tiny_mag_ptr, leftover_ptr, leftover_msize);
- this_msize = msize;
- }
-
-return_tiny_alloc:
- tiny_mag_ptr->mag_num_objects++;
- tiny_mag_ptr->mag_num_bytes_in_objects += TINY_BYTES_FOR_MSIZE(this_msize);
-
- // Check that the region cookie is intact and update the region's bytes in use count
- tiny_region_t region = TINY_REGION_FOR_PTR(ptr);
- region_check_cookie(region, ®ION_COOKIE_FOR_TINY_REGION(region));
-
- region_trailer_t *trailer = REGION_TRAILER_FOR_TINY_REGION(region);
- size_t bytes_used = trailer->bytes_used + TINY_BYTES_FOR_MSIZE(this_msize);
- trailer->bytes_used = (unsigned int)bytes_used;
- trailer->objects_in_use++;
-
- // Emptiness discriminant
- if (bytes_used < DENSITY_THRESHOLD(TINY_HEAP_SIZE)) {
- /* After this allocation the region is still sparse, so it must have been even more so before
- * the allocation. That implies the region is already correctly marked. Do nothing. */
- } else {
- /* Region has crossed threshold from sparsity to density. Mark it not "suitable" on the
- * recirculation candidates list. */
- trailer->recirc_suitable = FALSE;
- }
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "in tiny_malloc_from_free_list(), ptr=%p, this_msize=%d, msize=%d\n", ptr, this_msize, msize);
- }
-#endif
- if (this_msize > 1) {
- set_tiny_meta_header_in_use(ptr, this_msize);
- } else {
- set_tiny_meta_header_in_use_1(ptr);
- }
- return ptr;
-}
-
-void *
-tiny_malloc_should_clear(rack_t *rack, msize_t msize, boolean_t cleared_requested)
-{
- void *ptr;
- mag_index_t mag_index = rack_get_thread_index(rack) % rack->num_magazines;
- magazine_t *tiny_mag_ptr = &(rack->magazines[mag_index]);
-
- MALLOC_TRACE(TRACE_tiny_malloc, (uintptr_t)rack, TINY_BYTES_FOR_MSIZE(msize), (uintptr_t)tiny_mag_ptr, cleared_requested);
-
-#if DEBUG_MALLOC
- if (DEPOT_MAGAZINE_INDEX == mag_index) {
- malloc_zone_error(rack->debug_flags, true, "malloc called for magazine index -1\n");
- return (NULL);
- }
-
- if (!msize) {
- malloc_zone_error(rack->debug_flags, true, "invariant broken (!msize) in allocation (region)\n");
- return (NULL);
- }
-#endif
-
- SZONE_MAGAZINE_PTR_LOCK(tiny_mag_ptr);
-
-#if CONFIG_TINY_CACHE
- ptr = tiny_mag_ptr->mag_last_free;
-
- if (tiny_mag_ptr->mag_last_free_msize == msize) {
- // we have a winner
- tiny_mag_ptr->mag_last_free = NULL;
- tiny_mag_ptr->mag_last_free_msize = 0;
- tiny_mag_ptr->mag_last_free_rgn = NULL;
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- CHECK(szone, __PRETTY_FUNCTION__);
-
- tiny_check_zero_or_clear(ptr, msize, cleared_requested);
-
-#if DEBUG_MALLOC
- if (LOG(szone, ptr)) {
- malloc_report(ASL_LEVEL_INFO, "in tiny_malloc_should_clear(), tiny cache ptr=%p, msize=%d\n", ptr, msize);
- }
-#endif
- return ptr;
- }
-#endif /* CONFIG_TINY_CACHE */
-
- while (1) {
- ptr = tiny_malloc_from_free_list(rack, tiny_mag_ptr, mag_index, msize);
- if (ptr) {
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- CHECK(szone, __PRETTY_FUNCTION__);
- tiny_check_zero_or_clear(ptr, msize, cleared_requested);
- return ptr;
- }
-
-#if CONFIG_RECIRC_DEPOT
- if (tiny_get_region_from_depot(rack, tiny_mag_ptr, mag_index, msize)) {
- ptr = tiny_malloc_from_free_list(rack, tiny_mag_ptr, mag_index, msize);
- if (ptr) {
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- CHECK(szone, __PRETTY_FUNCTION__);
- tiny_check_zero_or_clear(ptr, msize, cleared_requested);
- return ptr;
- }
- }
-#endif // CONFIG_RECIRC_DEPOT
-
- // The magazine is exhausted. A new region (heap) must be allocated to satisfy this call to malloc().
- // The allocation, an mmap() system call, will be performed outside the magazine spin locks by the first
- // thread that suffers the exhaustion. That thread accquires the magazine_alloc_lock, then drops the
- // magazine lock to allow freeing threads to proceed. Allocating thrads that arrive later are excluded
- // from the critial section by the alloc lock. When those are unblocked, they succeed in the code above.
- //
- // Note that we need to trylock the alloc lock to avoid a deadlock, since we can't block on the alloc
- // lock while holding the magazine lock
- if (os_likely(_malloc_lock_trylock(&tiny_mag_ptr->magazine_alloc_lock))) {
- // We got the alloc lock, so we are the thread that should allocate a new region
- void *fresh_region;
-
- // time to create a new region (do this outside the magazine lock)
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- fresh_region = mvm_allocate_pages(TINY_REGION_SIZE,
- TINY_BLOCKS_ALIGN,
- MALLOC_FIX_GUARD_PAGE_FLAGS(rack->debug_flags),
- VM_MEMORY_MALLOC_TINY);
- SZONE_MAGAZINE_PTR_LOCK(tiny_mag_ptr);
-
- // DTrace USDT Probe
- MAGMALLOC_ALLOCREGION(TINY_SZONE_FROM_RACK(rack), (int)mag_index, fresh_region, TINY_REGION_SIZE);
-
- if (!fresh_region) { // out of memory!
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- _malloc_lock_unlock(&tiny_mag_ptr->magazine_alloc_lock);
- return NULL;
- }
-
- region_set_cookie(®ION_COOKIE_FOR_TINY_REGION(fresh_region));
- ptr = tiny_malloc_from_region_no_lock(rack, tiny_mag_ptr, mag_index, msize, fresh_region);
-
- // we don't clear or zero-check because this freshly allocated space
- // is pristine
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- _malloc_lock_unlock(&tiny_mag_ptr->magazine_alloc_lock);
- CHECK(szone, __PRETTY_FUNCTION__);
- return ptr;
- } else {
- // We failed to get the alloc lock, so someone else is allocating.
- // Drop the magazine lock...
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
-
- // Wait for the other thread on the alloc lock
- _malloc_lock_lock(&tiny_mag_ptr->magazine_alloc_lock);
- _malloc_lock_unlock(&tiny_mag_ptr->magazine_alloc_lock);
-
- // Reacquire the magazine lock to go around the loop again
- SZONE_MAGAZINE_PTR_LOCK(tiny_mag_ptr);
- }
- }
- /* NOTREACHED */
-}
-
-size_t
-tiny_size(rack_t *rack, const void *ptr)
-{
- if (tiny_region_for_ptr_no_lock(rack, ptr)) {
- if (TINY_INDEX_FOR_PTR(ptr) >= NUM_TINY_BLOCKS) {
-malloc_printf("NO ZONE for ptr %p\n", ptr);
- return 0;
- }
-
- boolean_t is_free;
- msize_t msize = get_tiny_meta_header(ptr, &is_free);
- if (is_free) {
- return 0;
- }
-
-#if CONFIG_TINY_CACHE
- {
- mag_index_t mag_index = MAGAZINE_INDEX_FOR_TINY_REGION(TINY_REGION_FOR_PTR(ptr));
- if (DEPOT_MAGAZINE_INDEX != mag_index) {
- magazine_t *tiny_mag_ptr = &rack->magazines[mag_index];
-
- if (msize < TINY_QUANTUM && ptr == tiny_mag_ptr->mag_last_free) {
- return 0;
- }
- } else {
- for (mag_index = 0; mag_index < rack->num_magazines; mag_index++) {
- magazine_t *tiny_mag_ptr = &(rack->magazines[mag_index]);
-
- if (msize < TINY_QUANTUM && ptr == tiny_mag_ptr->mag_last_free) {
- return 0;
- }
- }
- }
- }
-#endif
- return TINY_BYTES_FOR_MSIZE(msize);
- }
-
- return 0;
-}
-
-static MALLOC_NOINLINE void
-free_tiny_botch(rack_t *rack, tiny_free_list_t *ptr)
-{
- malloc_zone_error(rack->debug_flags, true, "Double free of object %p\n", ptr);
-}
-
-void
-free_tiny(rack_t *rack, void *ptr, region_t tiny_region, size_t known_size,
- boolean_t partial_free)
-{
- msize_t msize;
- boolean_t is_free;
- mag_index_t mag_index = MAGAZINE_INDEX_FOR_TINY_REGION(tiny_region);
- magazine_t *tiny_mag_ptr = &(rack->magazines[mag_index]);
- uint32_t flags = 0;
-
- MALLOC_TRACE(TRACE_tiny_free, (uintptr_t)rack, (uintptr_t)ptr, (uintptr_t)tiny_mag_ptr, known_size);
-
- // ptr is known to be in tiny_region
- if (known_size) {
- msize = TINY_MSIZE_FOR_BYTES(known_size + TINY_QUANTUM - 1);
- } else {
- msize = get_tiny_meta_header(ptr, &is_free);
- if (is_free) {
- free_tiny_botch(rack, ptr);
- return;
- }
- }
-#if DEBUG_MALLOC
- if (!msize) {
- malloc_report(ASL_LEVEL_ERR, "*** free_tiny() block in use is too large: %p\n", ptr);
- return;
- }
-#endif
-
- if (malloc_zero_policy == MALLOC_ZERO_ON_FREE) {
- memset(ptr, '\0', TINY_BYTES_FOR_MSIZE(msize));
- }
-
- SZONE_MAGAZINE_PTR_LOCK(tiny_mag_ptr);
-
-#if CONFIG_TINY_CACHE
- // Depot does not participate in CONFIG_TINY_CACHE since it can't be directly malloc()'d
- if (DEPOT_MAGAZINE_INDEX != mag_index && !partial_free) {
- if (msize < TINY_QUANTUM) { // to see if the bits fit in the last 4 bits
- void *ptr2 = tiny_mag_ptr->mag_last_free; // Might be NULL
- msize_t msize2 = tiny_mag_ptr->mag_last_free_msize;
- region_t rgn2 = tiny_mag_ptr->mag_last_free_rgn;
-
- /* check that we don't already have this pointer in the cache */
- if (ptr == ptr2) {
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- free_tiny_botch(rack, ptr);
- return;
- }
-
- if (malloc_zero_policy != MALLOC_ZERO_ON_FREE) {
- if ((rack->debug_flags & MALLOC_DO_SCRIBBLE) && msize) {
- memset(ptr, SCRABBLE_BYTE, TINY_BYTES_FOR_MSIZE(msize));
- }
- }
-
- tiny_mag_ptr->mag_last_free = ptr;
- tiny_mag_ptr->mag_last_free_msize = msize;
- tiny_mag_ptr->mag_last_free_rgn = tiny_region;
-
- if (!ptr2) {
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- CHECK(szone, __PRETTY_FUNCTION__);
- return;
- }
-
- msize = msize2;
- ptr = ptr2;
- tiny_region = rgn2;
- flags |= TINY_FREE_FLAG_FROM_CACHE;
- }
- }
-#endif /* CONFIG_TINY_CACHE */
-
- // Now in the time it took to acquire the lock, the region may have migrated
- // from one magazine to another. I.e. trailer->mag_index is volatile.
- // In which case the magazine lock we obtained (namely magazines[mag_index].mag_lock)
- // is stale. If so, keep on tryin' ...
- region_trailer_t *trailer = REGION_TRAILER_FOR_TINY_REGION(tiny_region);
- mag_index_t refreshed_index;
-
- while (mag_index != (refreshed_index = trailer->mag_index)) { // Note assignment
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- mag_index = refreshed_index;
- tiny_mag_ptr = &(rack->magazines[mag_index]);
- SZONE_MAGAZINE_PTR_LOCK(tiny_mag_ptr);
- }
-
- if (partial_free) {
- flags |= TINY_FREE_FLAG_PARTIAL;
- }
-
- if (tiny_free_no_lock(rack, tiny_mag_ptr, mag_index, tiny_region, ptr,
- msize, flags)) {
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- }
-
- CHECK(szone, __PRETTY_FUNCTION__);
-}
-
-unsigned
-tiny_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;
-
- mag_index_t mag_index = rack_get_thread_index(&szone->tiny_rack) % szone->tiny_rack.num_magazines;
- magazine_t *tiny_mag_ptr = &(szone->tiny_rack.magazines[mag_index]);
-
- // 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_MAGAZINE_PTR_LOCK(tiny_mag_ptr);
-
- // 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->tiny_rack, tiny_mag_ptr, mag_index, msize);
- if (!ptr) {
- break;
- }
-
- *results++ = ptr;
- found++;
- }
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- return found;
-}
-
-void
-tiny_batch_free(szone_t *szone, void **to_be_freed, unsigned count)
-{
- unsigned cc = 0;
- void *ptr;
- region_t tiny_region = NULL;
- boolean_t is_free;
- msize_t msize;
- magazine_t *tiny_mag_ptr = NULL;
- mag_index_t mag_index = -1;
-
- // 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__);
- while (cc < count) {
- ptr = to_be_freed[cc];
- if (ptr) {
- if (NULL == tiny_region || tiny_region != TINY_REGION_FOR_PTR(ptr)) { // region same as last iteration?
- if (tiny_mag_ptr) { // non-NULL iff magazine lock taken
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- tiny_mag_ptr = NULL;
- }
-
- tiny_region = tiny_region_for_ptr_no_lock(&szone->tiny_rack, ptr);
-
- if (tiny_region) {
- tiny_mag_ptr = mag_lock_zine_for_region_trailer(szone->tiny_rack.magazines,
- REGION_TRAILER_FOR_TINY_REGION(tiny_region),
- MAGAZINE_INDEX_FOR_TINY_REGION(tiny_region));
- mag_index = MAGAZINE_INDEX_FOR_TINY_REGION(tiny_region);
- }
- }
- 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
- }
- if (malloc_zero_policy == MALLOC_ZERO_ON_FREE) {
- memset(ptr, '\0', TINY_BYTES_FOR_MSIZE(msize));
- }
- if (!tiny_free_no_lock(&szone->tiny_rack, tiny_mag_ptr, mag_index, tiny_region, ptr, msize, 0)) {
- // Arrange to re-acquire magazine lock
- tiny_mag_ptr = NULL;
- tiny_region = NULL;
- }
- to_be_freed[cc] = NULL;
- } else {
- // No region in this zone claims ptr; let the standard free deal with it
- break;
- }
- }
- cc++;
- }
-
- if (tiny_mag_ptr) {
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- tiny_mag_ptr = NULL;
- }
-}
-
-
-void
-print_tiny_free_list(task_t task, memory_reader_t reader,
- print_task_printer_t printer, rack_t *rack)
-{
- tiny_free_list_t *ptr;
- _SIMPLE_STRING b = _simple_salloc();
- mag_index_t mag_index;
-
- if (b) {
- rack_t *mapped_rack;
- magazine_t *mapped_magazines;
- if (reader(task, (vm_address_t)rack, sizeof(struct rack_s),
- (void **)&mapped_rack)) {
- printer("Failed to map tiny rack\n");
- return;
- }
- _simple_sappend(b, "Tiny free sizes:\n");
- if (reader(task, (vm_address_t)mapped_rack->magazines,
- mapped_rack->num_magazines * sizeof(magazine_t),
- (void **)&mapped_magazines)) {
- printer("Failed to map tiny rack magazines\n");
- return;
- }
-
- for (mag_index = -1; mag_index < mapped_rack->num_magazines; mag_index++) {
- grain_t slot = 0;
- if (mag_index == -1) {
- _simple_sprintf(b, "\tRecirc depot: ");
- } else {
- _simple_sprintf(b, "\tMagazine %d: ", mag_index);
- }
- while (slot <= NUM_TINY_SLOTS) {
- ptr = mapped_magazines[mag_index].mag_free_list[slot].p;
- if (ptr) {
- _simple_sprintf(b, "%s%y[%d]; ",
- (slot == NUM_TINY_SLOTS) ? ">=" : "",
- (slot + 1) * TINY_QUANTUM,
- free_list_count(task, reader, printer, mapped_rack,
- (free_list_t){ .p = ptr }));
- }
- slot++;
- }
- _simple_sappend(b, "\n");
- }
- printer("%s\n", _simple_string(b));
- _simple_sfree(b);
- }
-}
-
-void
-print_tiny_region(task_t task, memory_reader_t reader,
- print_task_printer_t printer, int level, region_t region,
- size_t bytes_at_start, size_t bytes_at_end)
-{
- unsigned counts[1024];
- unsigned in_use = 0;
- uintptr_t start = (uintptr_t)TINY_REGION_HEAP_BASE(region);
- uintptr_t current = start + bytes_at_start;
- uintptr_t limit = (uintptr_t)TINY_REGION_HEAP_END(region) - bytes_at_end;
- uintptr_t mapped_start;
- boolean_t is_free;
- msize_t msize;
- unsigned ci;
- _SIMPLE_STRING b;
- uintptr_t pgTot = 0;
-
- if (reader(task, (vm_address_t)start, TINY_REGION_SIZE,
- (void **)&mapped_start)) {
- printer("Failed to map tiny region at %p\n", start);
- return;
- }
- off_t start_offset = mapped_start - start;
- region_t mapped_region = (region_t)mapped_start;
-
- if (region == HASHRING_REGION_DEALLOCATED) {
- if ((b = _simple_salloc()) != NULL) {
- _simple_sprintf(b, "Tiny region [unknown address] was returned to the OS\n");
- printer("%s\n", _simple_string(b));
- _simple_sfree(b);
- }
- return;
- }
-
- memset(counts, 0, sizeof(counts));
- while (current < limit) {
- msize = get_tiny_meta_header_offset((void *)current, start_offset, &is_free);
- if (is_free && !msize && (current == start)) {
- // first block is all free
- uintptr_t pgLo = round_page_quanta(start + sizeof(tiny_free_list_t) + sizeof(msize_t));
- uintptr_t pgHi = trunc_page_quanta(start + TINY_REGION_SIZE - sizeof(msize_t));
-
- if (pgLo < pgHi) {
- pgTot += (pgHi - pgLo);
- }
- break;
- }
- if (!msize) {
- printer("*** error with %p: msize=%d\n", (void *)current, (unsigned)msize);
- break;
- }
- if (!is_free) {
- // block in use
- if (msize > NUM_TINY_SLOTS) {
- printer("*** error at %p msize for in_use is %d\n", (void *)current, msize);
- }
- if (msize < 1024) {
- counts[msize]++;
- }
- in_use++;
- } else {
- uintptr_t pgLo = round_page_quanta(current + sizeof(tiny_free_list_t) + sizeof(msize_t));
- uintptr_t pgHi = trunc_page_quanta(current + TINY_BYTES_FOR_MSIZE(msize) - sizeof(msize_t));
-
- if (pgLo < pgHi) {
- pgTot += (pgHi - pgLo);
- }
- }
- current += TINY_BYTES_FOR_MSIZE(msize);
- }
- if ((b = _simple_salloc()) != NULL) {
- mag_index_t mag_index = MAGAZINE_INDEX_FOR_TINY_REGION(mapped_region);
- _simple_sprintf(b, "Tiny region [%p-%p, %y] \t", (void *)start, TINY_REGION_HEAP_END(region), (int)TINY_REGION_SIZE);
- if (mag_index == DEPOT_MAGAZINE_INDEX) {
- _simple_sprintf(b, "Recirc depot \t");
- } else {
- _simple_sprintf(b, "Magazine=%d \t", mag_index);
- }
- _simple_sprintf(b, "Allocations in use=%d \t Bytes in use=%ly (%d%%) \t",
- in_use, BYTES_USED_FOR_TINY_REGION(mapped_region),
- (int)(100.0F * BYTES_USED_FOR_TINY_REGION(mapped_region))/TINY_REGION_SIZE);
- if (bytes_at_end || bytes_at_start) {
- _simple_sprintf(b, "Untouched=%ly ", bytes_at_end + bytes_at_start);
- }
- if (mag_index == DEPOT_MAGAZINE_INDEX) {
- _simple_sprintf(b, "Advised MADV_FREE=%ly", pgTot);
- } else {
- _simple_sprintf(b, "Fragments subject to reclamation=%ly", pgTot);
-#if CONFIG_RECIRC_DEPOT
- _simple_sprintf(b, tiny_region_below_recirc_threshold(mapped_region) ?
- "\tEmpty enough to be moved to recirc depot" :
- "\tNot empty enough to be moved to recirc depot");
-#endif // CONFIG_RECIRC_DEPOT
- }
- if (level >= MALLOC_VERBOSE_PRINT_LEVEL && in_use) {
- _simple_sappend(b, "\n\tSizes in use: ");
- for (ci = 0; ci < 1024; ci++) {
- if (counts[ci]) {
- _simple_sprintf(b, "%y[%d] ", TINY_BYTES_FOR_MSIZE(ci), counts[ci]);
- }
- }
- }
- printer("%s\n", _simple_string(b));
- _simple_sfree(b);
- }
-}
-
-static char *tiny_freelist_fail_msg = "check: tiny free list incorrect ";
-
-#define TINY_FREELIST_FAIL(fmt, ...) \
- malloc_zone_check_fail(tiny_freelist_fail_msg, \
- " (slot=%u), counter=%d\n" fmt, slot, counter, __VA_ARGS__);
-
-boolean_t
-tiny_free_list_check(rack_t *rack, grain_t slot, unsigned counter)
-{
- mag_index_t mag_index;
-
- for (mag_index = -1; mag_index < rack->num_magazines; mag_index++) {
- magazine_t *tiny_mag_ptr = &(rack->magazines[mag_index]);
- SZONE_MAGAZINE_PTR_LOCK(tiny_mag_ptr);
-
- unsigned count = 0;
- tiny_free_list_t *ptr = rack->magazines[mag_index].mag_free_list[slot].p;
- boolean_t is_free;
- tiny_free_list_t *previous = NULL;
-
- while (ptr) {
- is_free = tiny_meta_header_is_free(ptr);
- if (!is_free) {
- TINY_FREELIST_FAIL("*** in-use ptr in free list slot=%u count=%d ptr=%p\n", slot, count, ptr);
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- return 0;
- }
- if (((uintptr_t)ptr) & (TINY_QUANTUM - 1)) {
- TINY_FREELIST_FAIL("*** unaligned ptr in free list slot=%u count=%d ptr=%p\n", slot, count, ptr);
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- return 0;
- }
- if (!tiny_region_for_ptr_no_lock(rack, ptr)) {
- TINY_FREELIST_FAIL("*** ptr not in szone slot=%d count=%u ptr=%p\n", slot, count, ptr);
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- return 0;
- }
- if (free_list_unchecksum_ptr(rack, &ptr->previous) != previous) {
- TINY_FREELIST_FAIL("*** previous incorrectly set slot=%u count=%d ptr=%p\n", slot, count, ptr);
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- return 0;
- }
- previous = ptr;
- ptr = free_list_unchecksum_ptr(rack, &ptr->next);
- count++;
- }
-
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- }
- return 1;
-}
-
-boolean_t
-tiny_check(rack_t *rack, unsigned counter)
-{
- size_t index;
-
- /* check tiny regions - chould check region count */
- for (index = 0; index < rack->region_generation->num_regions_allocated; ++index) {
- region_t tiny = rack->region_generation->hashed_regions[index];
-
- if (HASHRING_REGION_DEALLOCATED == tiny) {
- continue;
- }
-
- if (tiny) {
- magazine_t *tiny_mag_ptr = mag_lock_zine_for_region_trailer(rack->magazines,
- REGION_TRAILER_FOR_TINY_REGION(tiny),
- MAGAZINE_INDEX_FOR_TINY_REGION(tiny));
-
- if (!tiny_check_region(rack, tiny, index, counter)) {
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- return 0;
- }
- SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
- }
- }
-
- /* check tiny free lists */
- for (index = 0; index < NUM_TINY_SLOTS; ++index) {
- if (!tiny_free_list_check(rack, (grain_t)index, counter)) {
- return 0;
- }
- }
-
- return 1;
-}