summaryrefslogtreecommitdiffstats
path: root/contrib/tools/python3/Include/internal/pycore_obmalloc.h
diff options
context:
space:
mode:
authorthegeorg <[email protected]>2024-02-19 02:38:52 +0300
committerthegeorg <[email protected]>2024-02-19 02:50:43 +0300
commitd96fa07134c06472bfee6718b5cfd1679196fc99 (patch)
tree31ec344fa9d3ff8dc038692516b6438dfbdb8a2d /contrib/tools/python3/Include/internal/pycore_obmalloc.h
parent452cf9e068aef7110e35e654c5d47eb80111ef89 (diff)
Sync contrib/tools/python3 layout with upstream
* Move src/ subdir contents to the top of the layout * Rename self-written lib -> lib2 to avoid CaseFolding warning from the VCS * Regenerate contrib/libs/python proxy-headers accordingly 4ccc62ac1511abcf0fed14ccade38e984e088f1e
Diffstat (limited to 'contrib/tools/python3/Include/internal/pycore_obmalloc.h')
-rw-r--r--contrib/tools/python3/Include/internal/pycore_obmalloc.h700
1 files changed, 700 insertions, 0 deletions
diff --git a/contrib/tools/python3/Include/internal/pycore_obmalloc.h b/contrib/tools/python3/Include/internal/pycore_obmalloc.h
new file mode 100644
index 00000000000..b1c00654ac1
--- /dev/null
+++ b/contrib/tools/python3/Include/internal/pycore_obmalloc.h
@@ -0,0 +1,700 @@
+#ifndef Py_INTERNAL_OBMALLOC_H
+#define Py_INTERNAL_OBMALLOC_H
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef Py_BUILD_CORE
+# error "this header requires Py_BUILD_CORE define"
+#endif
+
+
+typedef unsigned int pymem_uint; /* assuming >= 16 bits */
+
+#undef uint
+#define uint pymem_uint
+
+
+/* An object allocator for Python.
+
+ Here is an introduction to the layers of the Python memory architecture,
+ showing where the object allocator is actually used (layer +2), It is
+ called for every object allocation and deallocation (PyObject_New/Del),
+ unless the object-specific allocators implement a proprietary allocation
+ scheme (ex.: ints use a simple free list). This is also the place where
+ the cyclic garbage collector operates selectively on container objects.
+
+
+ Object-specific allocators
+ _____ ______ ______ ________
+ [ int ] [ dict ] [ list ] ... [ string ] Python core |
++3 | <----- Object-specific memory -----> | <-- Non-object memory --> |
+ _______________________________ | |
+ [ Python's object allocator ] | |
++2 | ####### Object memory ####### | <------ Internal buffers ------> |
+ ______________________________________________________________ |
+ [ Python's raw memory allocator (PyMem_ API) ] |
++1 | <----- Python memory (under PyMem manager's control) ------> | |
+ __________________________________________________________________
+ [ Underlying general-purpose allocator (ex: C library malloc) ]
+ 0 | <------ Virtual memory allocated for the python process -------> |
+
+ =========================================================================
+ _______________________________________________________________________
+ [ OS-specific Virtual Memory Manager (VMM) ]
+-1 | <--- Kernel dynamic storage allocation & management (page-based) ---> |
+ __________________________________ __________________________________
+ [ ] [ ]
+-2 | <-- Physical memory: ROM/RAM --> | | <-- Secondary storage (swap) --> |
+
+*/
+/*==========================================================================*/
+
+/* A fast, special-purpose memory allocator for small blocks, to be used
+ on top of a general-purpose malloc -- heavily based on previous art. */
+
+/* Vladimir Marangozov -- August 2000 */
+
+/*
+ * "Memory management is where the rubber meets the road -- if we do the wrong
+ * thing at any level, the results will not be good. And if we don't make the
+ * levels work well together, we are in serious trouble." (1)
+ *
+ * (1) Paul R. Wilson, Mark S. Johnstone, Michael Neely, and David Boles,
+ * "Dynamic Storage Allocation: A Survey and Critical Review",
+ * in Proc. 1995 Int'l. Workshop on Memory Management, September 1995.
+ */
+
+/* #undef WITH_MEMORY_LIMITS */ /* disable mem limit checks */
+
+/*==========================================================================*/
+
+/*
+ * Allocation strategy abstract:
+ *
+ * For small requests, the allocator sub-allocates <Big> blocks of memory.
+ * Requests greater than SMALL_REQUEST_THRESHOLD bytes are routed to the
+ * system's allocator.
+ *
+ * Small requests are grouped in size classes spaced 8 bytes apart, due
+ * to the required valid alignment of the returned address. Requests of
+ * a particular size are serviced from memory pools of 4K (one VMM page).
+ * Pools are fragmented on demand and contain free lists of blocks of one
+ * particular size class. In other words, there is a fixed-size allocator
+ * for each size class. Free pools are shared by the different allocators
+ * thus minimizing the space reserved for a particular size class.
+ *
+ * This allocation strategy is a variant of what is known as "simple
+ * segregated storage based on array of free lists". The main drawback of
+ * simple segregated storage is that we might end up with lot of reserved
+ * memory for the different free lists, which degenerate in time. To avoid
+ * this, we partition each free list in pools and we share dynamically the
+ * reserved space between all free lists. This technique is quite efficient
+ * for memory intensive programs which allocate mainly small-sized blocks.
+ *
+ * For small requests we have the following table:
+ *
+ * Request in bytes Size of allocated block Size class idx
+ * ----------------------------------------------------------------
+ * 1-8 8 0
+ * 9-16 16 1
+ * 17-24 24 2
+ * 25-32 32 3
+ * 33-40 40 4
+ * 41-48 48 5
+ * 49-56 56 6
+ * 57-64 64 7
+ * 65-72 72 8
+ * ... ... ...
+ * 497-504 504 62
+ * 505-512 512 63
+ *
+ * 0, SMALL_REQUEST_THRESHOLD + 1 and up: routed to the underlying
+ * allocator.
+ */
+
+/*==========================================================================*/
+
+/*
+ * -- Main tunable settings section --
+ */
+
+/*
+ * Alignment of addresses returned to the user. 8-bytes alignment works
+ * on most current architectures (with 32-bit or 64-bit address buses).
+ * The alignment value is also used for grouping small requests in size
+ * classes spaced ALIGNMENT bytes apart.
+ *
+ * You shouldn't change this unless you know what you are doing.
+ */
+
+#if SIZEOF_VOID_P > 4
+#define ALIGNMENT 16 /* must be 2^N */
+#define ALIGNMENT_SHIFT 4
+#else
+#define ALIGNMENT 8 /* must be 2^N */
+#define ALIGNMENT_SHIFT 3
+#endif
+
+/* Return the number of bytes in size class I, as a uint. */
+#define INDEX2SIZE(I) (((pymem_uint)(I) + 1) << ALIGNMENT_SHIFT)
+
+/*
+ * Max size threshold below which malloc requests are considered to be
+ * small enough in order to use preallocated memory pools. You can tune
+ * this value according to your application behaviour and memory needs.
+ *
+ * Note: a size threshold of 512 guarantees that newly created dictionaries
+ * will be allocated from preallocated memory pools on 64-bit.
+ *
+ * The following invariants must hold:
+ * 1) ALIGNMENT <= SMALL_REQUEST_THRESHOLD <= 512
+ * 2) SMALL_REQUEST_THRESHOLD is evenly divisible by ALIGNMENT
+ *
+ * Although not required, for better performance and space efficiency,
+ * it is recommended that SMALL_REQUEST_THRESHOLD is set to a power of 2.
+ */
+#define SMALL_REQUEST_THRESHOLD 512
+#define NB_SMALL_SIZE_CLASSES (SMALL_REQUEST_THRESHOLD / ALIGNMENT)
+
+/*
+ * The system's VMM page size can be obtained on most unices with a
+ * getpagesize() call or deduced from various header files. To make
+ * things simpler, we assume that it is 4K, which is OK for most systems.
+ * It is probably better if this is the native page size, but it doesn't
+ * have to be. In theory, if SYSTEM_PAGE_SIZE is larger than the native page
+ * size, then `POOL_ADDR(p)->arenaindex' could rarely cause a segmentation
+ * violation fault. 4K is apparently OK for all the platforms that python
+ * currently targets.
+ */
+#define SYSTEM_PAGE_SIZE (4 * 1024)
+
+/*
+ * Maximum amount of memory managed by the allocator for small requests.
+ */
+#ifdef WITH_MEMORY_LIMITS
+#ifndef SMALL_MEMORY_LIMIT
+#define SMALL_MEMORY_LIMIT (64 * 1024 * 1024) /* 64 MB -- more? */
+#endif
+#endif
+
+#if !defined(WITH_PYMALLOC_RADIX_TREE)
+/* Use radix-tree to track arena memory regions, for address_in_range().
+ * Enable by default since it allows larger pool sizes. Can be disabled
+ * using -DWITH_PYMALLOC_RADIX_TREE=0 */
+#define WITH_PYMALLOC_RADIX_TREE 1
+#endif
+
+#if SIZEOF_VOID_P > 4
+/* on 64-bit platforms use larger pools and arenas if we can */
+#define USE_LARGE_ARENAS
+#if WITH_PYMALLOC_RADIX_TREE
+/* large pools only supported if radix-tree is enabled */
+#define USE_LARGE_POOLS
+#endif
+#endif
+
+/*
+ * The allocator sub-allocates <Big> blocks of memory (called arenas) aligned
+ * on a page boundary. This is a reserved virtual address space for the
+ * current process (obtained through a malloc()/mmap() call). In no way this
+ * means that the memory arenas will be used entirely. A malloc(<Big>) is
+ * usually an address range reservation for <Big> bytes, unless all pages within
+ * this space are referenced subsequently. So malloc'ing big blocks and not
+ * using them does not mean "wasting memory". It's an addressable range
+ * wastage...
+ *
+ * Arenas are allocated with mmap() on systems supporting anonymous memory
+ * mappings to reduce heap fragmentation.
+ */
+#ifdef USE_LARGE_ARENAS
+#define ARENA_BITS 20 /* 1 MiB */
+#else
+#define ARENA_BITS 18 /* 256 KiB */
+#endif
+#define ARENA_SIZE (1 << ARENA_BITS)
+#define ARENA_SIZE_MASK (ARENA_SIZE - 1)
+
+#ifdef WITH_MEMORY_LIMITS
+#define MAX_ARENAS (SMALL_MEMORY_LIMIT / ARENA_SIZE)
+#endif
+
+/*
+ * Size of the pools used for small blocks. Must be a power of 2.
+ */
+#ifdef USE_LARGE_POOLS
+#define POOL_BITS 14 /* 16 KiB */
+#else
+#define POOL_BITS 12 /* 4 KiB */
+#endif
+#define POOL_SIZE (1 << POOL_BITS)
+#define POOL_SIZE_MASK (POOL_SIZE - 1)
+
+#if !WITH_PYMALLOC_RADIX_TREE
+#if POOL_SIZE != SYSTEM_PAGE_SIZE
+# error "pool size must be equal to system page size"
+#endif
+#endif
+
+#define MAX_POOLS_IN_ARENA (ARENA_SIZE / POOL_SIZE)
+#if MAX_POOLS_IN_ARENA * POOL_SIZE != ARENA_SIZE
+# error "arena size not an exact multiple of pool size"
+#endif
+
+/*
+ * -- End of tunable settings section --
+ */
+
+/*==========================================================================*/
+
+/* When you say memory, my mind reasons in terms of (pointers to) blocks */
+typedef uint8_t pymem_block;
+
+/* Pool for small blocks. */
+struct pool_header {
+ union { pymem_block *_padding;
+ uint count; } ref; /* number of allocated blocks */
+ pymem_block *freeblock; /* pool's free list head */
+ struct pool_header *nextpool; /* next pool of this size class */
+ struct pool_header *prevpool; /* previous pool "" */
+ uint arenaindex; /* index into arenas of base adr */
+ uint szidx; /* block size class index */
+ uint nextoffset; /* bytes to virgin block */
+ uint maxnextoffset; /* largest valid nextoffset */
+};
+
+typedef struct pool_header *poolp;
+
+/* Record keeping for arenas. */
+struct arena_object {
+ /* The address of the arena, as returned by malloc. Note that 0
+ * will never be returned by a successful malloc, and is used
+ * here to mark an arena_object that doesn't correspond to an
+ * allocated arena.
+ */
+ uintptr_t address;
+
+ /* Pool-aligned pointer to the next pool to be carved off. */
+ pymem_block* pool_address;
+
+ /* The number of available pools in the arena: free pools + never-
+ * allocated pools.
+ */
+ uint nfreepools;
+
+ /* The total number of pools in the arena, whether or not available. */
+ uint ntotalpools;
+
+ /* Singly-linked list of available pools. */
+ struct pool_header* freepools;
+
+ /* Whenever this arena_object is not associated with an allocated
+ * arena, the nextarena member is used to link all unassociated
+ * arena_objects in the singly-linked `unused_arena_objects` list.
+ * The prevarena member is unused in this case.
+ *
+ * When this arena_object is associated with an allocated arena
+ * with at least one available pool, both members are used in the
+ * doubly-linked `usable_arenas` list, which is maintained in
+ * increasing order of `nfreepools` values.
+ *
+ * Else this arena_object is associated with an allocated arena
+ * all of whose pools are in use. `nextarena` and `prevarena`
+ * are both meaningless in this case.
+ */
+ struct arena_object* nextarena;
+ struct arena_object* prevarena;
+};
+
+#define POOL_OVERHEAD _Py_SIZE_ROUND_UP(sizeof(struct pool_header), ALIGNMENT)
+
+#define DUMMY_SIZE_IDX 0xffff /* size class of newly cached pools */
+
+/* Round pointer P down to the closest pool-aligned address <= P, as a poolp */
+#define POOL_ADDR(P) ((poolp)_Py_ALIGN_DOWN((P), POOL_SIZE))
+
+/* Return total number of blocks in pool of size index I, as a uint. */
+#define NUMBLOCKS(I) ((pymem_uint)(POOL_SIZE - POOL_OVERHEAD) / INDEX2SIZE(I))
+
+/*==========================================================================*/
+
+/*
+ * Pool table -- headed, circular, doubly-linked lists of partially used pools.
+
+This is involved. For an index i, usedpools[i+i] is the header for a list of
+all partially used pools holding small blocks with "size class idx" i. So
+usedpools[0] corresponds to blocks of size 8, usedpools[2] to blocks of size
+16, and so on: index 2*i <-> blocks of size (i+1)<<ALIGNMENT_SHIFT.
+
+Pools are carved off an arena's highwater mark (an arena_object's pool_address
+member) as needed. Once carved off, a pool is in one of three states forever
+after:
+
+used == partially used, neither empty nor full
+ At least one block in the pool is currently allocated, and at least one
+ block in the pool is not currently allocated (note this implies a pool
+ has room for at least two blocks).
+ This is a pool's initial state, as a pool is created only when malloc
+ needs space.
+ The pool holds blocks of a fixed size, and is in the circular list headed
+ at usedpools[i] (see above). It's linked to the other used pools of the
+ same size class via the pool_header's nextpool and prevpool members.
+ If all but one block is currently allocated, a malloc can cause a
+ transition to the full state. If all but one block is not currently
+ allocated, a free can cause a transition to the empty state.
+
+full == all the pool's blocks are currently allocated
+ On transition to full, a pool is unlinked from its usedpools[] list.
+ It's not linked to from anything then anymore, and its nextpool and
+ prevpool members are meaningless until it transitions back to used.
+ A free of a block in a full pool puts the pool back in the used state.
+ Then it's linked in at the front of the appropriate usedpools[] list, so
+ that the next allocation for its size class will reuse the freed block.
+
+empty == all the pool's blocks are currently available for allocation
+ On transition to empty, a pool is unlinked from its usedpools[] list,
+ and linked to the front of its arena_object's singly-linked freepools list,
+ via its nextpool member. The prevpool member has no meaning in this case.
+ Empty pools have no inherent size class: the next time a malloc finds
+ an empty list in usedpools[], it takes the first pool off of freepools.
+ If the size class needed happens to be the same as the size class the pool
+ last had, some pool initialization can be skipped.
+
+
+Block Management
+
+Blocks within pools are again carved out as needed. pool->freeblock points to
+the start of a singly-linked list of free blocks within the pool. When a
+block is freed, it's inserted at the front of its pool's freeblock list. Note
+that the available blocks in a pool are *not* linked all together when a pool
+is initialized. Instead only "the first two" (lowest addresses) blocks are
+set up, returning the first such block, and setting pool->freeblock to a
+one-block list holding the second such block. This is consistent with that
+pymalloc strives at all levels (arena, pool, and block) never to touch a piece
+of memory until it's actually needed.
+
+So long as a pool is in the used state, we're certain there *is* a block
+available for allocating, and pool->freeblock is not NULL. If pool->freeblock
+points to the end of the free list before we've carved the entire pool into
+blocks, that means we simply haven't yet gotten to one of the higher-address
+blocks. The offset from the pool_header to the start of "the next" virgin
+block is stored in the pool_header nextoffset member, and the largest value
+of nextoffset that makes sense is stored in the maxnextoffset member when a
+pool is initialized. All the blocks in a pool have been passed out at least
+once when and only when nextoffset > maxnextoffset.
+
+
+Major obscurity: While the usedpools vector is declared to have poolp
+entries, it doesn't really. It really contains two pointers per (conceptual)
+poolp entry, the nextpool and prevpool members of a pool_header. The
+excruciating initialization code below fools C so that
+
+ usedpool[i+i]
+
+"acts like" a genuine poolp, but only so long as you only reference its
+nextpool and prevpool members. The "- 2*sizeof(pymem_block *)" gibberish is
+compensating for that a pool_header's nextpool and prevpool members
+immediately follow a pool_header's first two members:
+
+ union { pymem_block *_padding;
+ uint count; } ref;
+ pymem_block *freeblock;
+
+each of which consume sizeof(pymem_block *) bytes. So what usedpools[i+i] really
+contains is a fudged-up pointer p such that *if* C believes it's a poolp
+pointer, then p->nextpool and p->prevpool are both p (meaning that the headed
+circular list is empty).
+
+It's unclear why the usedpools setup is so convoluted. It could be to
+minimize the amount of cache required to hold this heavily-referenced table
+(which only *needs* the two interpool pointer members of a pool_header). OTOH,
+referencing code has to remember to "double the index" and doing so isn't
+free, usedpools[0] isn't a strictly legal pointer, and we're crucially relying
+on that C doesn't insert any padding anywhere in a pool_header at or before
+the prevpool member.
+**************************************************************************** */
+
+#define OBMALLOC_USED_POOLS_SIZE (2 * ((NB_SMALL_SIZE_CLASSES + 7) / 8) * 8)
+
+struct _obmalloc_pools {
+ poolp used[OBMALLOC_USED_POOLS_SIZE];
+};
+
+
+/*==========================================================================
+Arena management.
+
+`arenas` is a vector of arena_objects. It contains maxarenas entries, some of
+which may not be currently used (== they're arena_objects that aren't
+currently associated with an allocated arena). Note that arenas proper are
+separately malloc'ed.
+
+Prior to Python 2.5, arenas were never free()'ed. Starting with Python 2.5,
+we do try to free() arenas, and use some mild heuristic strategies to increase
+the likelihood that arenas eventually can be freed.
+
+unused_arena_objects
+
+ This is a singly-linked list of the arena_objects that are currently not
+ being used (no arena is associated with them). Objects are taken off the
+ head of the list in new_arena(), and are pushed on the head of the list in
+ PyObject_Free() when the arena is empty. Key invariant: an arena_object
+ is on this list if and only if its .address member is 0.
+
+usable_arenas
+
+ This is a doubly-linked list of the arena_objects associated with arenas
+ that have pools available. These pools are either waiting to be reused,
+ or have not been used before. The list is sorted to have the most-
+ allocated arenas first (ascending order based on the nfreepools member).
+ This means that the next allocation will come from a heavily used arena,
+ which gives the nearly empty arenas a chance to be returned to the system.
+ In my unscientific tests this dramatically improved the number of arenas
+ that could be freed.
+
+Note that an arena_object associated with an arena all of whose pools are
+currently in use isn't on either list.
+
+Changed in Python 3.8: keeping usable_arenas sorted by number of free pools
+used to be done by one-at-a-time linear search when an arena's number of
+free pools changed. That could, overall, consume time quadratic in the
+number of arenas. That didn't really matter when there were only a few
+hundred arenas (typical!), but could be a timing disaster when there were
+hundreds of thousands. See bpo-37029.
+
+Now we have a vector of "search fingers" to eliminate the need to search:
+nfp2lasta[nfp] returns the last ("rightmost") arena in usable_arenas
+with nfp free pools. This is NULL if and only if there is no arena with
+nfp free pools in usable_arenas.
+*/
+
+/* How many arena_objects do we initially allocate?
+ * 16 = can allocate 16 arenas = 16 * ARENA_SIZE = 4MB before growing the
+ * `arenas` vector.
+ */
+#define INITIAL_ARENA_OBJECTS 16
+
+struct _obmalloc_mgmt {
+ /* Array of objects used to track chunks of memory (arenas). */
+ struct arena_object* arenas;
+ /* Number of slots currently allocated in the `arenas` vector. */
+ uint maxarenas;
+
+ /* The head of the singly-linked, NULL-terminated list of available
+ * arena_objects.
+ */
+ struct arena_object* unused_arena_objects;
+
+ /* The head of the doubly-linked, NULL-terminated at each end, list of
+ * arena_objects associated with arenas that have pools available.
+ */
+ struct arena_object* usable_arenas;
+
+ /* nfp2lasta[nfp] is the last arena in usable_arenas with nfp free pools */
+ struct arena_object* nfp2lasta[MAX_POOLS_IN_ARENA + 1];
+
+ /* Number of arenas allocated that haven't been free()'d. */
+ size_t narenas_currently_allocated;
+
+ /* Total number of times malloc() called to allocate an arena. */
+ size_t ntimes_arena_allocated;
+ /* High water mark (max value ever seen) for narenas_currently_allocated. */
+ size_t narenas_highwater;
+
+ Py_ssize_t raw_allocated_blocks;
+};
+
+
+#if WITH_PYMALLOC_RADIX_TREE
+/*==========================================================================*/
+/* radix tree for tracking arena usage. If enabled, used to implement
+ address_in_range().
+
+ memory address bit allocation for keys
+
+ 64-bit pointers, IGNORE_BITS=0 and 2^20 arena size:
+ 15 -> MAP_TOP_BITS
+ 15 -> MAP_MID_BITS
+ 14 -> MAP_BOT_BITS
+ 20 -> ideal aligned arena
+ ----
+ 64
+
+ 64-bit pointers, IGNORE_BITS=16, and 2^20 arena size:
+ 16 -> IGNORE_BITS
+ 10 -> MAP_TOP_BITS
+ 10 -> MAP_MID_BITS
+ 8 -> MAP_BOT_BITS
+ 20 -> ideal aligned arena
+ ----
+ 64
+
+ 32-bit pointers and 2^18 arena size:
+ 14 -> MAP_BOT_BITS
+ 18 -> ideal aligned arena
+ ----
+ 32
+
+*/
+
+#if SIZEOF_VOID_P == 8
+
+/* number of bits in a pointer */
+#define POINTER_BITS 64
+
+/* High bits of memory addresses that will be ignored when indexing into the
+ * radix tree. Setting this to zero is the safe default. For most 64-bit
+ * machines, setting this to 16 would be safe. The kernel would not give
+ * user-space virtual memory addresses that have significant information in
+ * those high bits. The main advantage to setting IGNORE_BITS > 0 is that less
+ * virtual memory will be used for the top and middle radix tree arrays. Those
+ * arrays are allocated in the BSS segment and so will typically consume real
+ * memory only if actually accessed.
+ */
+#define IGNORE_BITS 0
+
+/* use the top and mid layers of the radix tree */
+#define USE_INTERIOR_NODES
+
+#elif SIZEOF_VOID_P == 4
+
+#define POINTER_BITS 32
+#define IGNORE_BITS 0
+
+#else
+
+ /* Currently this code works for 64-bit or 32-bit pointers only. */
+#error "obmalloc radix tree requires 64-bit or 32-bit pointers."
+
+#endif /* SIZEOF_VOID_P */
+
+/* arena_coverage_t members require this to be true */
+#if ARENA_BITS >= 32
+# error "arena size must be < 2^32"
+#endif
+
+/* the lower bits of the address that are not ignored */
+#define ADDRESS_BITS (POINTER_BITS - IGNORE_BITS)
+
+#ifdef USE_INTERIOR_NODES
+/* number of bits used for MAP_TOP and MAP_MID nodes */
+#define INTERIOR_BITS ((ADDRESS_BITS - ARENA_BITS + 2) / 3)
+#else
+#define INTERIOR_BITS 0
+#endif
+
+#define MAP_TOP_BITS INTERIOR_BITS
+#define MAP_TOP_LENGTH (1 << MAP_TOP_BITS)
+#define MAP_TOP_MASK (MAP_TOP_LENGTH - 1)
+
+#define MAP_MID_BITS INTERIOR_BITS
+#define MAP_MID_LENGTH (1 << MAP_MID_BITS)
+#define MAP_MID_MASK (MAP_MID_LENGTH - 1)
+
+#define MAP_BOT_BITS (ADDRESS_BITS - ARENA_BITS - 2*INTERIOR_BITS)
+#define MAP_BOT_LENGTH (1 << MAP_BOT_BITS)
+#define MAP_BOT_MASK (MAP_BOT_LENGTH - 1)
+
+#define MAP_BOT_SHIFT ARENA_BITS
+#define MAP_MID_SHIFT (MAP_BOT_BITS + MAP_BOT_SHIFT)
+#define MAP_TOP_SHIFT (MAP_MID_BITS + MAP_MID_SHIFT)
+
+#define AS_UINT(p) ((uintptr_t)(p))
+#define MAP_BOT_INDEX(p) ((AS_UINT(p) >> MAP_BOT_SHIFT) & MAP_BOT_MASK)
+#define MAP_MID_INDEX(p) ((AS_UINT(p) >> MAP_MID_SHIFT) & MAP_MID_MASK)
+#define MAP_TOP_INDEX(p) ((AS_UINT(p) >> MAP_TOP_SHIFT) & MAP_TOP_MASK)
+
+#if IGNORE_BITS > 0
+/* Return the ignored part of the pointer address. Those bits should be same
+ * for all valid pointers if IGNORE_BITS is set correctly.
+ */
+#define HIGH_BITS(p) (AS_UINT(p) >> ADDRESS_BITS)
+#else
+#define HIGH_BITS(p) 0
+#endif
+
+
+/* This is the leaf of the radix tree. See arena_map_mark_used() for the
+ * meaning of these members. */
+typedef struct {
+ int32_t tail_hi;
+ int32_t tail_lo;
+} arena_coverage_t;
+
+typedef struct arena_map_bot {
+ /* The members tail_hi and tail_lo are accessed together. So, it
+ * better to have them as an array of structs, rather than two
+ * arrays.
+ */
+ arena_coverage_t arenas[MAP_BOT_LENGTH];
+} arena_map_bot_t;
+
+#ifdef USE_INTERIOR_NODES
+typedef struct arena_map_mid {
+ struct arena_map_bot *ptrs[MAP_MID_LENGTH];
+} arena_map_mid_t;
+
+typedef struct arena_map_top {
+ struct arena_map_mid *ptrs[MAP_TOP_LENGTH];
+} arena_map_top_t;
+#endif
+
+struct _obmalloc_usage {
+ /* The root of radix tree. Note that by initializing like this, the memory
+ * should be in the BSS. The OS will only memory map pages as the MAP_MID
+ * nodes get used (OS pages are demand loaded as needed).
+ */
+#ifdef USE_INTERIOR_NODES
+ arena_map_top_t arena_map_root;
+ /* accounting for number of used interior nodes */
+ int arena_map_mid_count;
+ int arena_map_bot_count;
+#else
+ arena_map_bot_t arena_map_root;
+#endif
+};
+
+#endif /* WITH_PYMALLOC_RADIX_TREE */
+
+
+struct _obmalloc_global_state {
+ int dump_debug_stats;
+ Py_ssize_t interpreter_leaks;
+};
+
+struct _obmalloc_state {
+ struct _obmalloc_pools pools;
+ struct _obmalloc_mgmt mgmt;
+#if WITH_PYMALLOC_RADIX_TREE
+ struct _obmalloc_usage usage;
+#endif
+};
+
+
+#undef uint
+
+
+/* Allocate memory directly from the O/S virtual memory system,
+ * where supported. Otherwise fallback on malloc */
+void *_PyObject_VirtualAlloc(size_t size);
+void _PyObject_VirtualFree(void *, size_t size);
+
+
+/* This function returns the number of allocated memory blocks, regardless of size */
+extern Py_ssize_t _Py_GetGlobalAllocatedBlocks(void);
+#define _Py_GetAllocatedBlocks() \
+ _Py_GetGlobalAllocatedBlocks()
+extern Py_ssize_t _PyInterpreterState_GetAllocatedBlocks(PyInterpreterState *);
+extern void _PyInterpreterState_FinalizeAllocatedBlocks(PyInterpreterState *);
+
+
+#ifdef WITH_PYMALLOC
+// Export the symbol for the 3rd party guppy3 project
+PyAPI_FUNC(int) _PyObject_DebugMallocStats(FILE *out);
+#endif
+
+
+#ifdef __cplusplus
+}
+#endif
+#endif // !Py_INTERNAL_OBMALLOC_H