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--- /dev/null
+++ libmalloc/libmalloc-374.100.5/src/magazine_tiny.c
@@ -0,0 +1,2782 @@
+/*
+ * 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 MALLOC_INLINE MALLOC_ALWAYS_INLINE
+mag_index_t
+tiny_mag_get_thread_index(void)
+{
+#if CONFIG_TINY_USES_HYPER_SHIFT
+ if (os_likely(_os_cpu_number_override == -1)) {
+ return _malloc_cpu_number() >> hyper_shift;
+ } else {
+ return _os_cpu_number_override >> hyper_shift;
+ }
+#else // CONFIG_SMALL_USES_HYPER_SHIFT
+ if (os_likely(_os_cpu_number_override == -1)) {
+ return _malloc_cpu_number();
+ } else {
+ return _os_cpu_number_override;
+ }
+#endif // CONFIG_SMALL_USES_HYPER_SHIFT
+}
+
+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
+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);
+ 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);
+ 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]);
+
+ /* FIXME: Would Uniprocessor benefit from recirc and MADV_FREE? */
+ if (rack->num_magazines == 1) { // Uniprocessor, single magazine, so no recirculation necessary
+ return 0;
+ }
+
+#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;
+
+ /* FIXME: Would Uniprocessor benefit from recirc and MADV_FREE? */
+ if (rack->num_magazines == 1) { // Uniprocessor, single magazine, so no recirculation necessary
+ /* NOTHING */
+ return TRUE; // Caller must do SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr)
+ } else 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
+
+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, boolean_t partial_free)
+{
+ 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);
+ 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);
+ 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
+ msize += next_msize;
+ }
+
+ // The tiny cache already scribbles free blocks as they go through the
+ // cache whenever msize < TINY_QUANTUM , so we do not need to do it here.
+ if ((rack->debug_flags & MALLOC_DO_SCRIBBLE) && msize && (msize >= TINY_QUANTUM)) {
+ 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 (!partial_free) {
+ 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.
+ set_tiny_meta_header_in_use(next_block + TINY_BYTES_FOR_MSIZE(coalesced_msize), 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);
+ 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));
+ }
+ } 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
+ 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);
+
+ 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);
+ tiny_update_region_free_list_for_remove(slot, ptr, next);
+ 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);
+ 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));
+ limit->p = leftover_ptr;
+ if (next) {
+ next->previous.u = free_list_checksum_ptr(rack, leftover_ptr);
+ }
+ leftover_ptr->previous = ptr->previous;
+ leftover_ptr->next = ptr->next;
+ set_tiny_meta_header_free(leftover_ptr, leftover_msize);
+#if DEBUG_MALLOC
+ if (LOG(szone, ptr)) {
+ malloc_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);
+ 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)) {
+ 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 = tiny_mag_get_thread_index() % 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__);
+ if (cleared_requested) {
+ memset(ptr, 0, TINY_BYTES_FOR_MSIZE(msize));
+ }
+#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__);
+ if (cleared_requested) {
+ memset(ptr, 0, TINY_BYTES_FOR_MSIZE(msize));
+ }
+ 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__);
+ if (cleared_requested) {
+ memset(ptr, 0, TINY_BYTES_FOR_MSIZE(msize));
+ }
+ 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 sets "alloc_underway" and enters a critical section.
+ // Threads arriving here later are excluded from the critical section, yield the CPU, and then retry the
+ // allocation. After some time the magazine is resupplied, the original thread leaves with its allocation,
+ // and retry-ing threads succeed in the code just above.
+ if (!tiny_mag_ptr->alloc_underway) {
+ void *fresh_region;
+
+ // time to create a new region (do this outside the magazine lock)
+ tiny_mag_ptr->alloc_underway = TRUE;
+ OSMemoryBarrier();
+ 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!
+ tiny_mag_ptr->alloc_underway = FALSE;
+ OSMemoryBarrier();
+ SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
+ 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 because this freshly allocated space is pristine
+ tiny_mag_ptr->alloc_underway = FALSE;
+ OSMemoryBarrier();
+ SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
+ CHECK(szone, __PRETTY_FUNCTION__);
+ return ptr;
+ } else {
+ SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr);
+ yield();
+ 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]);
+
+ 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
+
+ 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 ((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;
+ }
+ }
+#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 (tiny_free_no_lock(rack, tiny_mag_ptr, mag_index, tiny_region, ptr,
+ msize, partial_free)) {
+ 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 = tiny_mag_get_thread_index() % 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 (!tiny_free_no_lock(&szone->tiny_rack, tiny_mag_ptr, mag_index, tiny_region, ptr, msize, false)) {
+ // 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;
+}