mirror of https://github.com/python/cpython.git
703 lines
27 KiB
C
703 lines
27 KiB
C
#ifndef Py_INTERNAL_OBMALLOC_H
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#define Py_INTERNAL_OBMALLOC_H
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#ifdef __cplusplus
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extern "C" {
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#endif
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#ifndef Py_BUILD_CORE
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# error "this header requires Py_BUILD_CORE define"
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#endif
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typedef unsigned int pymem_uint; /* assuming >= 16 bits */
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#undef uint
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#define uint pymem_uint
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/* An object allocator for Python.
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Here is an introduction to the layers of the Python memory architecture,
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showing where the object allocator is actually used (layer +2), It is
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called for every object allocation and deallocation (PyObject_New/Del),
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unless the object-specific allocators implement a proprietary allocation
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scheme (ex.: ints use a simple free list). This is also the place where
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the cyclic garbage collector operates selectively on container objects.
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Object-specific allocators
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_____ ______ ______ ________
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[ int ] [ dict ] [ list ] ... [ string ] Python core |
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+3 | <----- Object-specific memory -----> | <-- Non-object memory --> |
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_______________________________ | |
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[ Python's object allocator ] | |
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+2 | ####### Object memory ####### | <------ Internal buffers ------> |
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______________________________________________________________ |
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[ Python's raw memory allocator (PyMem_ API) ] |
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+1 | <----- Python memory (under PyMem manager's control) ------> | |
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__________________________________________________________________
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[ Underlying general-purpose allocator (ex: C library malloc) ]
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0 | <------ Virtual memory allocated for the python process -------> |
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=========================================================================
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_______________________________________________________________________
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[ OS-specific Virtual Memory Manager (VMM) ]
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-1 | <--- Kernel dynamic storage allocation & management (page-based) ---> |
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__________________________________ __________________________________
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[ ] [ ]
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-2 | <-- Physical memory: ROM/RAM --> | | <-- Secondary storage (swap) --> |
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*/
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/*==========================================================================*/
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/* A fast, special-purpose memory allocator for small blocks, to be used
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on top of a general-purpose malloc -- heavily based on previous art. */
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/* Vladimir Marangozov -- August 2000 */
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/*
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* "Memory management is where the rubber meets the road -- if we do the wrong
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* thing at any level, the results will not be good. And if we don't make the
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* levels work well together, we are in serious trouble." (1)
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*
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* (1) Paul R. Wilson, Mark S. Johnstone, Michael Neely, and David Boles,
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* "Dynamic Storage Allocation: A Survey and Critical Review",
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* in Proc. 1995 Int'l. Workshop on Memory Management, September 1995.
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*/
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/* #undef WITH_MEMORY_LIMITS */ /* disable mem limit checks */
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/*==========================================================================*/
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/*
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* Allocation strategy abstract:
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*
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* For small requests, the allocator sub-allocates <Big> blocks of memory.
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* Requests greater than SMALL_REQUEST_THRESHOLD bytes are routed to the
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* system's allocator.
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*
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* Small requests are grouped in size classes spaced 8 bytes apart, due
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* to the required valid alignment of the returned address. Requests of
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* a particular size are serviced from memory pools of 4K (one VMM page).
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* Pools are fragmented on demand and contain free lists of blocks of one
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* particular size class. In other words, there is a fixed-size allocator
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* for each size class. Free pools are shared by the different allocators
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* thus minimizing the space reserved for a particular size class.
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*
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* This allocation strategy is a variant of what is known as "simple
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* segregated storage based on array of free lists". The main drawback of
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* simple segregated storage is that we might end up with lot of reserved
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* memory for the different free lists, which degenerate in time. To avoid
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* this, we partition each free list in pools and we share dynamically the
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* reserved space between all free lists. This technique is quite efficient
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* for memory intensive programs which allocate mainly small-sized blocks.
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*
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* For small requests we have the following table:
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*
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* Request in bytes Size of allocated block Size class idx
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* ----------------------------------------------------------------
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* 1-8 8 0
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* 9-16 16 1
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* 17-24 24 2
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* 25-32 32 3
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* 33-40 40 4
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* 41-48 48 5
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* 49-56 56 6
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* 57-64 64 7
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* 65-72 72 8
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* ... ... ...
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* 497-504 504 62
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* 505-512 512 63
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*
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* 0, SMALL_REQUEST_THRESHOLD + 1 and up: routed to the underlying
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* allocator.
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*/
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/*==========================================================================*/
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/*
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* -- Main tunable settings section --
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*/
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/*
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* Alignment of addresses returned to the user. 8-bytes alignment works
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* on most current architectures (with 32-bit or 64-bit address buses).
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* The alignment value is also used for grouping small requests in size
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* classes spaced ALIGNMENT bytes apart.
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*
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* You shouldn't change this unless you know what you are doing.
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*/
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#if SIZEOF_VOID_P > 4
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#define ALIGNMENT 16 /* must be 2^N */
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#define ALIGNMENT_SHIFT 4
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#else
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#define ALIGNMENT 8 /* must be 2^N */
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#define ALIGNMENT_SHIFT 3
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#endif
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/* Return the number of bytes in size class I, as a uint. */
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#define INDEX2SIZE(I) (((pymem_uint)(I) + 1) << ALIGNMENT_SHIFT)
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/*
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* Max size threshold below which malloc requests are considered to be
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* small enough in order to use preallocated memory pools. You can tune
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* this value according to your application behaviour and memory needs.
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*
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* Note: a size threshold of 512 guarantees that newly created dictionaries
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* will be allocated from preallocated memory pools on 64-bit.
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*
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* The following invariants must hold:
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* 1) ALIGNMENT <= SMALL_REQUEST_THRESHOLD <= 512
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* 2) SMALL_REQUEST_THRESHOLD is evenly divisible by ALIGNMENT
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*
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* Although not required, for better performance and space efficiency,
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* it is recommended that SMALL_REQUEST_THRESHOLD is set to a power of 2.
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*/
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#define SMALL_REQUEST_THRESHOLD 512
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#define NB_SMALL_SIZE_CLASSES (SMALL_REQUEST_THRESHOLD / ALIGNMENT)
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/*
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* The system's VMM page size can be obtained on most unices with a
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* getpagesize() call or deduced from various header files. To make
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* things simpler, we assume that it is 4K, which is OK for most systems.
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* It is probably better if this is the native page size, but it doesn't
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* have to be. In theory, if SYSTEM_PAGE_SIZE is larger than the native page
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* size, then `POOL_ADDR(p)->arenaindex' could rarely cause a segmentation
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* violation fault. 4K is apparently OK for all the platforms that python
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* currently targets.
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*/
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#define SYSTEM_PAGE_SIZE (4 * 1024)
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/*
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* Maximum amount of memory managed by the allocator for small requests.
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*/
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#ifdef WITH_MEMORY_LIMITS
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#ifndef SMALL_MEMORY_LIMIT
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#define SMALL_MEMORY_LIMIT (64 * 1024 * 1024) /* 64 MB -- more? */
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#endif
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#endif
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#if !defined(WITH_PYMALLOC_RADIX_TREE)
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/* Use radix-tree to track arena memory regions, for address_in_range().
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* Enable by default since it allows larger pool sizes. Can be disabled
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* using -DWITH_PYMALLOC_RADIX_TREE=0 */
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#define WITH_PYMALLOC_RADIX_TREE 1
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#endif
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#if SIZEOF_VOID_P > 4
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/* on 64-bit platforms use larger pools and arenas if we can */
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#define USE_LARGE_ARENAS
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#if WITH_PYMALLOC_RADIX_TREE
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/* large pools only supported if radix-tree is enabled */
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#define USE_LARGE_POOLS
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#endif
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#endif
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/*
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* The allocator sub-allocates <Big> blocks of memory (called arenas) aligned
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* on a page boundary. This is a reserved virtual address space for the
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* current process (obtained through a malloc()/mmap() call). In no way this
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* means that the memory arenas will be used entirely. A malloc(<Big>) is
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* usually an address range reservation for <Big> bytes, unless all pages within
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* this space are referenced subsequently. So malloc'ing big blocks and not
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* using them does not mean "wasting memory". It's an addressable range
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* wastage...
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*
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* Arenas are allocated with mmap() on systems supporting anonymous memory
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* mappings to reduce heap fragmentation.
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*/
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#ifdef USE_LARGE_ARENAS
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#define ARENA_BITS 20 /* 1 MiB */
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#else
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#define ARENA_BITS 18 /* 256 KiB */
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#endif
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#define ARENA_SIZE (1 << ARENA_BITS)
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#define ARENA_SIZE_MASK (ARENA_SIZE - 1)
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#ifdef WITH_MEMORY_LIMITS
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#define MAX_ARENAS (SMALL_MEMORY_LIMIT / ARENA_SIZE)
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#endif
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/*
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* Size of the pools used for small blocks. Must be a power of 2.
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*/
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#ifdef USE_LARGE_POOLS
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#define POOL_BITS 14 /* 16 KiB */
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#else
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#define POOL_BITS 12 /* 4 KiB */
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#endif
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#define POOL_SIZE (1 << POOL_BITS)
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#define POOL_SIZE_MASK (POOL_SIZE - 1)
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#if !WITH_PYMALLOC_RADIX_TREE
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#if POOL_SIZE != SYSTEM_PAGE_SIZE
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# error "pool size must be equal to system page size"
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#endif
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#endif
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#define MAX_POOLS_IN_ARENA (ARENA_SIZE / POOL_SIZE)
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#if MAX_POOLS_IN_ARENA * POOL_SIZE != ARENA_SIZE
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# error "arena size not an exact multiple of pool size"
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#endif
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/*
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* -- End of tunable settings section --
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*/
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/*==========================================================================*/
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/* When you say memory, my mind reasons in terms of (pointers to) blocks */
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typedef uint8_t pymem_block;
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/* Pool for small blocks. */
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struct pool_header {
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union { pymem_block *_padding;
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uint count; } ref; /* number of allocated blocks */
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pymem_block *freeblock; /* pool's free list head */
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struct pool_header *nextpool; /* next pool of this size class */
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struct pool_header *prevpool; /* previous pool "" */
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uint arenaindex; /* index into arenas of base adr */
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uint szidx; /* block size class index */
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uint nextoffset; /* bytes to virgin block */
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uint maxnextoffset; /* largest valid nextoffset */
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};
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typedef struct pool_header *poolp;
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/* Record keeping for arenas. */
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struct arena_object {
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/* The address of the arena, as returned by malloc. Note that 0
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* will never be returned by a successful malloc, and is used
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* here to mark an arena_object that doesn't correspond to an
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* allocated arena.
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*/
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uintptr_t address;
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/* Pool-aligned pointer to the next pool to be carved off. */
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pymem_block* pool_address;
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/* The number of available pools in the arena: free pools + never-
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* allocated pools.
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*/
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uint nfreepools;
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/* The total number of pools in the arena, whether or not available. */
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uint ntotalpools;
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/* Singly-linked list of available pools. */
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struct pool_header* freepools;
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/* Whenever this arena_object is not associated with an allocated
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* arena, the nextarena member is used to link all unassociated
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* arena_objects in the singly-linked `unused_arena_objects` list.
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* The prevarena member is unused in this case.
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*
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* When this arena_object is associated with an allocated arena
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* with at least one available pool, both members are used in the
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* doubly-linked `usable_arenas` list, which is maintained in
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* increasing order of `nfreepools` values.
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*
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* Else this arena_object is associated with an allocated arena
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* all of whose pools are in use. `nextarena` and `prevarena`
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* are both meaningless in this case.
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*/
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struct arena_object* nextarena;
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struct arena_object* prevarena;
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};
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#define POOL_OVERHEAD _Py_SIZE_ROUND_UP(sizeof(struct pool_header), ALIGNMENT)
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#define DUMMY_SIZE_IDX 0xffff /* size class of newly cached pools */
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/* Round pointer P down to the closest pool-aligned address <= P, as a poolp */
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#define POOL_ADDR(P) ((poolp)_Py_ALIGN_DOWN((P), POOL_SIZE))
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/* Return total number of blocks in pool of size index I, as a uint. */
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#define NUMBLOCKS(I) ((pymem_uint)(POOL_SIZE - POOL_OVERHEAD) / INDEX2SIZE(I))
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/*==========================================================================*/
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/*
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* Pool table -- headed, circular, doubly-linked lists of partially used pools.
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This is involved. For an index i, usedpools[i+i] is the header for a list of
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all partially used pools holding small blocks with "size class idx" i. So
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usedpools[0] corresponds to blocks of size 8, usedpools[2] to blocks of size
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16, and so on: index 2*i <-> blocks of size (i+1)<<ALIGNMENT_SHIFT.
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Pools are carved off an arena's highwater mark (an arena_object's pool_address
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member) as needed. Once carved off, a pool is in one of three states forever
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after:
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used == partially used, neither empty nor full
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At least one block in the pool is currently allocated, and at least one
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block in the pool is not currently allocated (note this implies a pool
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has room for at least two blocks).
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This is a pool's initial state, as a pool is created only when malloc
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needs space.
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The pool holds blocks of a fixed size, and is in the circular list headed
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at usedpools[i] (see above). It's linked to the other used pools of the
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same size class via the pool_header's nextpool and prevpool members.
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If all but one block is currently allocated, a malloc can cause a
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transition to the full state. If all but one block is not currently
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allocated, a free can cause a transition to the empty state.
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full == all the pool's blocks are currently allocated
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On transition to full, a pool is unlinked from its usedpools[] list.
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It's not linked to from anything then anymore, and its nextpool and
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prevpool members are meaningless until it transitions back to used.
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A free of a block in a full pool puts the pool back in the used state.
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Then it's linked in at the front of the appropriate usedpools[] list, so
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that the next allocation for its size class will reuse the freed block.
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empty == all the pool's blocks are currently available for allocation
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On transition to empty, a pool is unlinked from its usedpools[] list,
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and linked to the front of its arena_object's singly-linked freepools list,
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via its nextpool member. The prevpool member has no meaning in this case.
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Empty pools have no inherent size class: the next time a malloc finds
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an empty list in usedpools[], it takes the first pool off of freepools.
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If the size class needed happens to be the same as the size class the pool
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last had, some pool initialization can be skipped.
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Block Management
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Blocks within pools are again carved out as needed. pool->freeblock points to
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the start of a singly-linked list of free blocks within the pool. When a
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block is freed, it's inserted at the front of its pool's freeblock list. Note
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that the available blocks in a pool are *not* linked all together when a pool
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is initialized. Instead only "the first two" (lowest addresses) blocks are
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set up, returning the first such block, and setting pool->freeblock to a
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one-block list holding the second such block. This is consistent with that
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pymalloc strives at all levels (arena, pool, and block) never to touch a piece
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of memory until it's actually needed.
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So long as a pool is in the used state, we're certain there *is* a block
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available for allocating, and pool->freeblock is not NULL. If pool->freeblock
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points to the end of the free list before we've carved the entire pool into
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blocks, that means we simply haven't yet gotten to one of the higher-address
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blocks. The offset from the pool_header to the start of "the next" virgin
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block is stored in the pool_header nextoffset member, and the largest value
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of nextoffset that makes sense is stored in the maxnextoffset member when a
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pool is initialized. All the blocks in a pool have been passed out at least
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once when and only when nextoffset > maxnextoffset.
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Major obscurity: While the usedpools vector is declared to have poolp
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entries, it doesn't really. It really contains two pointers per (conceptual)
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poolp entry, the nextpool and prevpool members of a pool_header. The
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excruciating initialization code below fools C so that
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usedpool[i+i]
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"acts like" a genuine poolp, but only so long as you only reference its
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nextpool and prevpool members. The "- 2*sizeof(pymem_block *)" gibberish is
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compensating for that a pool_header's nextpool and prevpool members
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immediately follow a pool_header's first two members:
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union { pymem_block *_padding;
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uint count; } ref;
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pymem_block *freeblock;
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each of which consume sizeof(pymem_block *) bytes. So what usedpools[i+i] really
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contains is a fudged-up pointer p such that *if* C believes it's a poolp
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pointer, then p->nextpool and p->prevpool are both p (meaning that the headed
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circular list is empty).
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It's unclear why the usedpools setup is so convoluted. It could be to
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minimize the amount of cache required to hold this heavily-referenced table
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(which only *needs* the two interpool pointer members of a pool_header). OTOH,
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referencing code has to remember to "double the index" and doing so isn't
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free, usedpools[0] isn't a strictly legal pointer, and we're crucially relying
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on that C doesn't insert any padding anywhere in a pool_header at or before
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the prevpool member.
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**************************************************************************** */
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#define OBMALLOC_USED_POOLS_SIZE (2 * ((NB_SMALL_SIZE_CLASSES + 7) / 8) * 8)
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struct _obmalloc_pools {
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poolp used[OBMALLOC_USED_POOLS_SIZE];
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};
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/*==========================================================================
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Arena management.
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`arenas` is a vector of arena_objects. It contains maxarenas entries, some of
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which may not be currently used (== they're arena_objects that aren't
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currently associated with an allocated arena). Note that arenas proper are
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separately malloc'ed.
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Prior to Python 2.5, arenas were never free()'ed. Starting with Python 2.5,
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we do try to free() arenas, and use some mild heuristic strategies to increase
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the likelihood that arenas eventually can be freed.
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unused_arena_objects
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This is a singly-linked list of the arena_objects that are currently not
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being used (no arena is associated with them). Objects are taken off the
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head of the list in new_arena(), and are pushed on the head of the list in
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PyObject_Free() when the arena is empty. Key invariant: an arena_object
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is on this list if and only if its .address member is 0.
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usable_arenas
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This is a doubly-linked list of the arena_objects associated with arenas
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that have pools available. These pools are either waiting to be reused,
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or have not been used before. The list is sorted to have the most-
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allocated arenas first (ascending order based on the nfreepools member).
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This means that the next allocation will come from a heavily used arena,
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which gives the nearly empty arenas a chance to be returned to the system.
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In my unscientific tests this dramatically improved the number of arenas
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that could be freed.
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Note that an arena_object associated with an arena all of whose pools are
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currently in use isn't on either list.
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Changed in Python 3.8: keeping usable_arenas sorted by number of free pools
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used to be done by one-at-a-time linear search when an arena's number of
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free pools changed. That could, overall, consume time quadratic in the
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number of arenas. That didn't really matter when there were only a few
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hundred arenas (typical!), but could be a timing disaster when there were
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hundreds of thousands. See bpo-37029.
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Now we have a vector of "search fingers" to eliminate the need to search:
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nfp2lasta[nfp] returns the last ("rightmost") arena in usable_arenas
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with nfp free pools. This is NULL if and only if there is no arena with
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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 *);
|
|
extern int _PyMem_init_obmalloc(PyInterpreterState *interp);
|
|
extern bool _PyMem_obmalloc_state_on_heap(PyInterpreterState *interp);
|
|
|
|
|
|
#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
|