From 9e87e7776f7ace66baaf7247233afdabd00c2b44 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Fri, 24 Nov 2017 12:09:24 +0100 Subject: bpo-32096: Remove obj and mem from _PyRuntime (#4532) bpo-32096, bpo-30860: Partially revert the commit 2ebc5ce42a8a9e047e790aefbf9a94811569b2b6: * Move structures back from Include/internal/mem.h to Objects/obmalloc.c * Remove _PyObject_Initialize() and _PyMem_Initialize() * Remove Include/internal/pymalloc.h * Add test_capi.test_pre_initialization_api(): Make sure that it's possible to call Py_DecodeLocale(), and then call Py_SetProgramName() with the decoded string, before Py_Initialize(). PyMem_RawMalloc() and Py_DecodeLocale() can be called again before _PyRuntimeState_Init(). Co-Authored-By: Eric Snow --- Include/internal/mem.h | 48 -- Include/internal/pymalloc.h | 443 ----------- Include/internal/pystate.h | 2 - Lib/test/test_capi.py | 10 + Makefile.pre.in | 1 - .../2017-11-24-01-13-58.bpo-32096.CQTHXJ.rst | 4 + Objects/obmalloc.c | 833 ++++++++++++++++----- PCbuild/pythoncore.vcxproj | 1 - PCbuild/pythoncore.vcxproj.filters | 5 +- Parser/pgenmain.c | 2 - Programs/_testembed.c | 23 + Python/pystate.c | 2 - 12 files changed, 685 insertions(+), 689 deletions(-) delete mode 100644 Include/internal/pymalloc.h create mode 100644 Misc/NEWS.d/next/Core and Builtins/2017-11-24-01-13-58.bpo-32096.CQTHXJ.rst diff --git a/Include/internal/mem.h b/Include/internal/mem.h index 471cdf4..a731e30 100644 --- a/Include/internal/mem.h +++ b/Include/internal/mem.h @@ -7,54 +7,6 @@ extern "C" { #include "objimpl.h" #include "pymem.h" -#ifdef WITH_PYMALLOC -#include "internal/pymalloc.h" -#endif - -/* Low-level memory runtime state */ - -struct _pymem_runtime_state { - struct _allocator_runtime_state { - PyMemAllocatorEx mem; - PyMemAllocatorEx obj; - PyMemAllocatorEx raw; - } allocators; -#ifdef WITH_PYMALLOC - /* Array of objects used to track chunks of memory (arenas). */ - struct arena_object* arenas; - /* 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; - /* Number of slots currently allocated in the `arenas` vector. */ - unsigned int maxarenas; - /* Number of arenas allocated that haven't been free()'d. */ - size_t narenas_currently_allocated; - /* High water mark (max value ever seen) for - * narenas_currently_allocated. */ - size_t narenas_highwater; - /* Total number of times malloc() called to allocate an arena. */ - size_t ntimes_arena_allocated; - poolp usedpools[MAX_POOLS]; - Py_ssize_t num_allocated_blocks; -#endif /* WITH_PYMALLOC */ - size_t serialno; /* incremented on each debug {m,re}alloc */ -}; - -PyAPI_FUNC(void) _PyMem_Initialize(struct _pymem_runtime_state *); - - -/* High-level memory runtime state */ - -struct _pyobj_runtime_state { - PyObjectArenaAllocator allocator_arenas; -}; - -PyAPI_FUNC(void) _PyObject_Initialize(struct _pyobj_runtime_state *); - /* GC runtime state */ diff --git a/Include/internal/pymalloc.h b/Include/internal/pymalloc.h deleted file mode 100644 index 723d9e7..0000000 --- a/Include/internal/pymalloc.h +++ /dev/null @@ -1,443 +0,0 @@ - -/* 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. - */ - -#ifndef Py_INTERNAL_PYMALLOC_H -#define Py_INTERNAL_PYMALLOC_H - -/* #undef WITH_MEMORY_LIMITS */ /* disable mem limit checks */ - -/*==========================================================================*/ - -/* - * Allocation strategy abstract: - * - * For small requests, the allocator sub-allocates 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 busses). - * 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. - */ -#define ALIGNMENT 8 /* must be 2^N */ -#define ALIGNMENT_SHIFT 3 - -/* Return the number of bytes in size class I, as a uint. */ -#define INDEX2SIZE(I) (((unsigned int)(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) - -#if NB_SMALL_SIZE_CLASSES > 64 -#error "NB_SMALL_SIZE_CLASSES should be less than 64" -#endif /* NB_SMALL_SIZE_CLASSES > 64 */ - -/* - * 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) -#define SYSTEM_PAGE_SIZE_MASK (SYSTEM_PAGE_SIZE - 1) - -/* - * 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 MiB -- more? */ -#endif -#endif - -/* - * The allocator sub-allocates 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() is - * usually an address range reservation for 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. - */ -#define ARENA_SIZE (256 << 10) /* 256 KiB */ - -#ifdef WITH_MEMORY_LIMITS -#define MAX_ARENAS (SMALL_MEMORY_LIMIT / ARENA_SIZE) -#endif - -/* - * Size of the pools used for small blocks. Should be a power of 2, - * between 1K and SYSTEM_PAGE_SIZE, that is: 1k, 2k, 4k. - */ -#define POOL_SIZE SYSTEM_PAGE_SIZE /* must be 2^N */ -#define POOL_SIZE_MASK SYSTEM_PAGE_SIZE_MASK - -/* - * -- End of tunable settings section -- - */ - -/*==========================================================================*/ - -/* - * Locking - * - * To reduce lock contention, it would probably be better to refine the - * crude function locking with per size class locking. I'm not positive - * however, whether it's worth switching to such locking policy because - * of the performance penalty it might introduce. - * - * The following macros describe the simplest (should also be the fastest) - * lock object on a particular platform and the init/fini/lock/unlock - * operations on it. The locks defined here are not expected to be recursive - * because it is assumed that they will always be called in the order: - * INIT, [LOCK, UNLOCK]*, FINI. - */ - -/* - * Python's threads are serialized, so object malloc locking is disabled. - */ -#define SIMPLELOCK_DECL(lock) /* simple lock declaration */ -#define SIMPLELOCK_INIT(lock) /* allocate (if needed) and initialize */ -#define SIMPLELOCK_FINI(lock) /* free/destroy an existing lock */ -#define SIMPLELOCK_LOCK(lock) /* acquire released lock */ -#define SIMPLELOCK_UNLOCK(lock) /* release acquired lock */ - -/* When you say memory, my mind reasons in terms of (pointers to) blocks */ -typedef uint8_t pyblock; - -/* Pool for small blocks. */ -struct pool_header { - union { pyblock *_padding; - unsigned int count; } ref; /* number of allocated blocks */ - pyblock *freeblock; /* pool's free list head */ - struct pool_header *nextpool; /* next pool of this size class */ - struct pool_header *prevpool; /* previous pool "" */ - unsigned int arenaindex; /* index into arenas of base adr */ - unsigned int szidx; /* block size class index */ - unsigned int nextoffset; /* bytes to virgin block */ - unsigned int 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. */ - pyblock* pool_address; - - /* The number of available pools in the arena: free pools + never- - * allocated pools. - */ - unsigned int nfreepools; - - /* The total number of pools in the arena, whether or not available. */ - unsigned int 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) \ - ((unsigned int)(POOL_SIZE - POOL_OVERHEAD) / INDEX2SIZE(I)) - -/*==========================================================================*/ - -/* - * This malloc lock - */ -SIMPLELOCK_DECL(_malloc_lock) -#define LOCK() SIMPLELOCK_LOCK(_malloc_lock) -#define UNLOCK() SIMPLELOCK_UNLOCK(_malloc_lock) -#define LOCK_INIT() SIMPLELOCK_INIT(_malloc_lock) -#define LOCK_FINI() SIMPLELOCK_FINI(_malloc_lock) - -/* - * 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)<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(block *)" gibberish is -compensating for that a pool_header's nextpool and prevpool members -immediately follow a pool_header's first two members: - - union { block *_padding; - uint count; } ref; - block *freeblock; - -each of which consume sizeof(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 MAX_POOLS (2 * ((NB_SMALL_SIZE_CLASSES + 7) / 8) * 8) - -/*========================================================================== -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. -*/ - -/* How many arena_objects do we initially allocate? - * 16 = can allocate 16 arenas = 16 * ARENA_SIZE = 4 MiB before growing the - * `arenas` vector. - */ -#define INITIAL_ARENA_OBJECTS 16 - -#endif /* Py_INTERNAL_PYMALLOC_H */ diff --git a/Include/internal/pystate.h b/Include/internal/pystate.h index 67b4a51..7056e10 100644 --- a/Include/internal/pystate.h +++ b/Include/internal/pystate.h @@ -64,9 +64,7 @@ typedef struct pyruntimestate { int nexitfuncs; void (*pyexitfunc)(void); - struct _pyobj_runtime_state obj; struct _gc_runtime_state gc; - struct _pymem_runtime_state mem; struct _warnings_runtime_state warnings; struct _ceval_runtime_state ceval; struct _gilstate_runtime_state gilstate; diff --git a/Lib/test/test_capi.py b/Lib/test/test_capi.py index bb5b2a3..2fe0fec 100644 --- a/Lib/test/test_capi.py +++ b/Lib/test/test_capi.py @@ -593,6 +593,16 @@ class EmbeddingTests(unittest.TestCase): self.maxDiff = None self.assertEqual(out.strip(), expected_output) + def test_pre_initialization_api(self): + """ + Checks the few parts of the C-API that work before the runtine + is initialized (via Py_Initialize()). + """ + env = dict(os.environ, PYTHONPATH=os.pathsep.join(sys.path)) + out, err = self.run_embedded_interpreter("pre_initialization_api", env=env) + self.assertEqual(out, '') + self.assertEqual(err, '') + class SkipitemTest(unittest.TestCase): diff --git a/Makefile.pre.in b/Makefile.pre.in index 566afba..d196d5f 100644 --- a/Makefile.pre.in +++ b/Makefile.pre.in @@ -1015,7 +1015,6 @@ PYTHON_HEADERS= \ $(srcdir)/Include/internal/ceval.h \ $(srcdir)/Include/internal/gil.h \ $(srcdir)/Include/internal/mem.h \ - $(srcdir)/Include/internal/pymalloc.h \ $(srcdir)/Include/internal/pystate.h \ $(srcdir)/Include/internal/warnings.h \ $(DTRACE_HEADERS) diff --git a/Misc/NEWS.d/next/Core and Builtins/2017-11-24-01-13-58.bpo-32096.CQTHXJ.rst b/Misc/NEWS.d/next/Core and Builtins/2017-11-24-01-13-58.bpo-32096.CQTHXJ.rst new file mode 100644 index 0000000..d2a770b --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2017-11-24-01-13-58.bpo-32096.CQTHXJ.rst @@ -0,0 +1,4 @@ +Revert memory allocator changes in the C API: move structures back from +_PyRuntime to Objects/obmalloc.c. The memory allocators are once again initialized +statically, and so PyMem_RawMalloc() and Py_DecodeLocale() can be +called before _PyRuntime_Initialize(). diff --git a/Objects/obmalloc.c b/Objects/obmalloc.c index 7c6973e..96a451e 100644 --- a/Objects/obmalloc.c +++ b/Objects/obmalloc.c @@ -1,6 +1,4 @@ #include "Python.h" -#include "internal/mem.h" -#include "internal/pystate.h" #include @@ -180,24 +178,39 @@ static struct { #define PYDBG_FUNCS \ _PyMem_DebugMalloc, _PyMem_DebugCalloc, _PyMem_DebugRealloc, _PyMem_DebugFree +static PyMemAllocatorEx _PyMem_Raw = { +#ifdef Py_DEBUG + &_PyMem_Debug.raw, PYRAWDBG_FUNCS +#else + NULL, PYRAW_FUNCS +#endif + }; -#define _PyMem_Raw _PyRuntime.mem.allocators.raw - -#define _PyMem _PyRuntime.mem.allocators.mem +static PyMemAllocatorEx _PyMem = { +#ifdef Py_DEBUG + &_PyMem_Debug.mem, PYDBG_FUNCS +#else + NULL, PYMEM_FUNCS +#endif + }; -#define _PyObject _PyRuntime.mem.allocators.obj +static PyMemAllocatorEx _PyObject = { +#ifdef Py_DEBUG + &_PyMem_Debug.obj, PYDBG_FUNCS +#else + NULL, PYOBJ_FUNCS +#endif + }; void _PyMem_GetDefaultRawAllocator(PyMemAllocatorEx *alloc_p) { - PyMemAllocatorEx pymem_raw = { #ifdef Py_DEBUG - &_PyMem_Debug.raw, PYRAWDBG_FUNCS + PyMemAllocatorEx alloc = {&_PyMem_Debug.raw, PYDBG_FUNCS}; #else - NULL, PYRAW_FUNCS + PyMemAllocatorEx alloc = {NULL, PYRAW_FUNCS}; #endif - }; - *alloc_p = pymem_raw; + *alloc_p = alloc; } int @@ -259,62 +272,22 @@ _PyMem_SetupAllocators(const char *opt) return 0; } +#undef PYRAW_FUNCS +#undef PYMEM_FUNCS +#undef PYOBJ_FUNCS +#undef PYRAWDBG_FUNCS +#undef PYDBG_FUNCS -void -_PyObject_Initialize(struct _pyobj_runtime_state *state) -{ - PyObjectArenaAllocator _PyObject_Arena = {NULL, +static PyObjectArenaAllocator _PyObject_Arena = {NULL, #ifdef MS_WINDOWS - _PyObject_ArenaVirtualAlloc, _PyObject_ArenaVirtualFree + _PyObject_ArenaVirtualAlloc, _PyObject_ArenaVirtualFree #elif defined(ARENAS_USE_MMAP) - _PyObject_ArenaMmap, _PyObject_ArenaMunmap + _PyObject_ArenaMmap, _PyObject_ArenaMunmap #else - _PyObject_ArenaMalloc, _PyObject_ArenaFree + _PyObject_ArenaMalloc, _PyObject_ArenaFree #endif }; - state->allocator_arenas = _PyObject_Arena; -} - - -void -_PyMem_Initialize(struct _pymem_runtime_state *state) -{ - PyMemAllocatorEx pymem = { -#ifdef Py_DEBUG - &_PyMem_Debug.mem, PYDBG_FUNCS -#else - NULL, PYMEM_FUNCS -#endif - }; - PyMemAllocatorEx pyobject = { -#ifdef Py_DEBUG - &_PyMem_Debug.obj, PYDBG_FUNCS -#else - NULL, PYOBJ_FUNCS -#endif - }; - - _PyMem_GetDefaultRawAllocator(&state->allocators.raw); - state->allocators.mem = pymem; - state->allocators.obj = pyobject; - -#ifdef WITH_PYMALLOC - Py_BUILD_ASSERT(NB_SMALL_SIZE_CLASSES == 64); - - for (int i = 0; i < 8; i++) { - for (int j = 0; j < 8; j++) { - int x = i * 8 + j; - poolp *addr = &(state->usedpools[2*(x)]); - poolp val = (poolp)((uint8_t *)addr - 2*sizeof(pyblock *)); - state->usedpools[x * 2] = val; - state->usedpools[x * 2 + 1] = val; - }; - }; -#endif /* WITH_PYMALLOC */ -} - - #ifdef WITH_PYMALLOC static int _PyMem_DebugEnabled(void) @@ -401,13 +374,13 @@ PyMem_SetAllocator(PyMemAllocatorDomain domain, PyMemAllocatorEx *allocator) void PyObject_GetArenaAllocator(PyObjectArenaAllocator *allocator) { - *allocator = _PyRuntime.obj.allocator_arenas; + *allocator = _PyObject_Arena; } void PyObject_SetArenaAllocator(PyObjectArenaAllocator *allocator) { - _PyRuntime.obj.allocator_arenas = *allocator; + _PyObject_Arena = *allocator; } void * @@ -442,8 +415,7 @@ PyMem_RawRealloc(void *ptr, size_t new_size) return _PyMem_Raw.realloc(_PyMem_Raw.ctx, ptr, new_size); } -void -PyMem_RawFree(void *ptr) +void PyMem_RawFree(void *ptr) { _PyMem_Raw.free(_PyMem_Raw.ctx, ptr); } @@ -563,10 +535,497 @@ static int running_on_valgrind = -1; #endif +/* 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 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 busses). + * 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. + */ +#define ALIGNMENT 8 /* must be 2^N */ +#define ALIGNMENT_SHIFT 3 + +/* Return the number of bytes in size class I, as a uint. */ +#define INDEX2SIZE(I) (((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) +#define SYSTEM_PAGE_SIZE_MASK (SYSTEM_PAGE_SIZE - 1) + +/* + * 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 + +/* + * The allocator sub-allocates 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() is + * usually an address range reservation for 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. + */ +#define ARENA_SIZE (256 << 10) /* 256KB */ + +#ifdef WITH_MEMORY_LIMITS +#define MAX_ARENAS (SMALL_MEMORY_LIMIT / ARENA_SIZE) +#endif + +/* + * Size of the pools used for small blocks. Should be a power of 2, + * between 1K and SYSTEM_PAGE_SIZE, that is: 1k, 2k, 4k. + */ +#define POOL_SIZE SYSTEM_PAGE_SIZE /* must be 2^N */ +#define POOL_SIZE_MASK SYSTEM_PAGE_SIZE_MASK + +/* + * -- End of tunable settings section -- + */ + +/*==========================================================================*/ + +/* + * Locking + * + * To reduce lock contention, it would probably be better to refine the + * crude function locking with per size class locking. I'm not positive + * however, whether it's worth switching to such locking policy because + * of the performance penalty it might introduce. + * + * The following macros describe the simplest (should also be the fastest) + * lock object on a particular platform and the init/fini/lock/unlock + * operations on it. The locks defined here are not expected to be recursive + * because it is assumed that they will always be called in the order: + * INIT, [LOCK, UNLOCK]*, FINI. + */ + +/* + * Python's threads are serialized, so object malloc locking is disabled. + */ +#define SIMPLELOCK_DECL(lock) /* simple lock declaration */ +#define SIMPLELOCK_INIT(lock) /* allocate (if needed) and initialize */ +#define SIMPLELOCK_FINI(lock) /* free/destroy an existing lock */ +#define SIMPLELOCK_LOCK(lock) /* acquire released lock */ +#define SIMPLELOCK_UNLOCK(lock) /* release acquired lock */ + +/* When you say memory, my mind reasons in terms of (pointers to) blocks */ +typedef uint8_t block; + +/* Pool for small blocks. */ +struct pool_header { + union { block *_padding; + uint count; } ref; /* number of allocated blocks */ + 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. */ + 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) ((uint)(POOL_SIZE - POOL_OVERHEAD) / INDEX2SIZE(I)) + +/*==========================================================================*/ + +/* + * This malloc lock + */ +SIMPLELOCK_DECL(_malloc_lock) +#define LOCK() SIMPLELOCK_LOCK(_malloc_lock) +#define UNLOCK() SIMPLELOCK_UNLOCK(_malloc_lock) +#define LOCK_INIT() SIMPLELOCK_INIT(_malloc_lock) +#define LOCK_FINI() SIMPLELOCK_FINI(_malloc_lock) + +/* + * 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)<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(block *)" gibberish is +compensating for that a pool_header's nextpool and prevpool members +immediately follow a pool_header's first two members: + + union { block *_padding; + uint count; } ref; + block *freeblock; + +each of which consume sizeof(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 PTA(x) ((poolp )((uint8_t *)&(usedpools[2*(x)]) - 2*sizeof(block *))) +#define PT(x) PTA(x), PTA(x) + +static poolp usedpools[2 * ((NB_SMALL_SIZE_CLASSES + 7) / 8) * 8] = { + PT(0), PT(1), PT(2), PT(3), PT(4), PT(5), PT(6), PT(7) +#if NB_SMALL_SIZE_CLASSES > 8 + , PT(8), PT(9), PT(10), PT(11), PT(12), PT(13), PT(14), PT(15) +#if NB_SMALL_SIZE_CLASSES > 16 + , PT(16), PT(17), PT(18), PT(19), PT(20), PT(21), PT(22), PT(23) +#if NB_SMALL_SIZE_CLASSES > 24 + , PT(24), PT(25), PT(26), PT(27), PT(28), PT(29), PT(30), PT(31) +#if NB_SMALL_SIZE_CLASSES > 32 + , PT(32), PT(33), PT(34), PT(35), PT(36), PT(37), PT(38), PT(39) +#if NB_SMALL_SIZE_CLASSES > 40 + , PT(40), PT(41), PT(42), PT(43), PT(44), PT(45), PT(46), PT(47) +#if NB_SMALL_SIZE_CLASSES > 48 + , PT(48), PT(49), PT(50), PT(51), PT(52), PT(53), PT(54), PT(55) +#if NB_SMALL_SIZE_CLASSES > 56 + , PT(56), PT(57), PT(58), PT(59), PT(60), PT(61), PT(62), PT(63) +#if NB_SMALL_SIZE_CLASSES > 64 +#error "NB_SMALL_SIZE_CLASSES should be less than 64" +#endif /* NB_SMALL_SIZE_CLASSES > 64 */ +#endif /* NB_SMALL_SIZE_CLASSES > 56 */ +#endif /* NB_SMALL_SIZE_CLASSES > 48 */ +#endif /* NB_SMALL_SIZE_CLASSES > 40 */ +#endif /* NB_SMALL_SIZE_CLASSES > 32 */ +#endif /* NB_SMALL_SIZE_CLASSES > 24 */ +#endif /* NB_SMALL_SIZE_CLASSES > 16 */ +#endif /* NB_SMALL_SIZE_CLASSES > 8 */ +}; + +/*========================================================================== +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. +*/ + +/* Array of objects used to track chunks of memory (arenas). */ +static struct arena_object* arenas = NULL; +/* Number of slots currently allocated in the `arenas` vector. */ +static uint maxarenas = 0; + +/* The head of the singly-linked, NULL-terminated list of available + * arena_objects. + */ +static struct arena_object* unused_arena_objects = NULL; + +/* The head of the doubly-linked, NULL-terminated at each end, list of + * arena_objects associated with arenas that have pools available. + */ +static struct arena_object* usable_arenas = NULL; + +/* 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 + +/* Number of arenas allocated that haven't been free()'d. */ +static size_t narenas_currently_allocated = 0; + +/* Total number of times malloc() called to allocate an arena. */ +static size_t ntimes_arena_allocated = 0; +/* High water mark (max value ever seen) for narenas_currently_allocated. */ +static size_t narenas_highwater = 0; + +static Py_ssize_t _Py_AllocatedBlocks = 0; + Py_ssize_t _Py_GetAllocatedBlocks(void) { - return _PyRuntime.mem.num_allocated_blocks; + return _Py_AllocatedBlocks; } @@ -590,7 +1049,7 @@ new_arena(void) if (debug_stats) _PyObject_DebugMallocStats(stderr); - if (_PyRuntime.mem.unused_arena_objects == NULL) { + if (unused_arena_objects == NULL) { uint i; uint numarenas; size_t nbytes; @@ -598,18 +1057,18 @@ new_arena(void) /* Double the number of arena objects on each allocation. * Note that it's possible for `numarenas` to overflow. */ - numarenas = _PyRuntime.mem.maxarenas ? _PyRuntime.mem.maxarenas << 1 : INITIAL_ARENA_OBJECTS; - if (numarenas <= _PyRuntime.mem.maxarenas) + numarenas = maxarenas ? maxarenas << 1 : INITIAL_ARENA_OBJECTS; + if (numarenas <= maxarenas) return NULL; /* overflow */ #if SIZEOF_SIZE_T <= SIZEOF_INT - if (numarenas > SIZE_MAX / sizeof(*_PyRuntime.mem.arenas)) + if (numarenas > SIZE_MAX / sizeof(*arenas)) return NULL; /* overflow */ #endif - nbytes = numarenas * sizeof(*_PyRuntime.mem.arenas); - arenaobj = (struct arena_object *)PyMem_RawRealloc(_PyRuntime.mem.arenas, nbytes); + nbytes = numarenas * sizeof(*arenas); + arenaobj = (struct arena_object *)PyMem_RawRealloc(arenas, nbytes); if (arenaobj == NULL) return NULL; - _PyRuntime.mem.arenas = arenaobj; + arenas = arenaobj; /* We might need to fix pointers that were copied. However, * new_arena only gets called when all the pages in the @@ -617,45 +1076,45 @@ new_arena(void) * into the old array. Thus, we don't have to worry about * invalid pointers. Just to be sure, some asserts: */ - assert(_PyRuntime.mem.usable_arenas == NULL); - assert(_PyRuntime.mem.unused_arena_objects == NULL); + assert(usable_arenas == NULL); + assert(unused_arena_objects == NULL); /* Put the new arenas on the unused_arena_objects list. */ - for (i = _PyRuntime.mem.maxarenas; i < numarenas; ++i) { - _PyRuntime.mem.arenas[i].address = 0; /* mark as unassociated */ - _PyRuntime.mem.arenas[i].nextarena = i < numarenas - 1 ? - &_PyRuntime.mem.arenas[i+1] : NULL; + for (i = maxarenas; i < numarenas; ++i) { + arenas[i].address = 0; /* mark as unassociated */ + arenas[i].nextarena = i < numarenas - 1 ? + &arenas[i+1] : NULL; } /* Update globals. */ - _PyRuntime.mem.unused_arena_objects = &_PyRuntime.mem.arenas[_PyRuntime.mem.maxarenas]; - _PyRuntime.mem.maxarenas = numarenas; + unused_arena_objects = &arenas[maxarenas]; + maxarenas = numarenas; } /* Take the next available arena object off the head of the list. */ - assert(_PyRuntime.mem.unused_arena_objects != NULL); - arenaobj = _PyRuntime.mem.unused_arena_objects; - _PyRuntime.mem.unused_arena_objects = arenaobj->nextarena; + assert(unused_arena_objects != NULL); + arenaobj = unused_arena_objects; + unused_arena_objects = arenaobj->nextarena; assert(arenaobj->address == 0); - address = _PyRuntime.obj.allocator_arenas.alloc(_PyRuntime.obj.allocator_arenas.ctx, ARENA_SIZE); + address = _PyObject_Arena.alloc(_PyObject_Arena.ctx, ARENA_SIZE); if (address == NULL) { /* The allocation failed: return NULL after putting the * arenaobj back. */ - arenaobj->nextarena = _PyRuntime.mem.unused_arena_objects; - _PyRuntime.mem.unused_arena_objects = arenaobj; + arenaobj->nextarena = unused_arena_objects; + unused_arena_objects = arenaobj; return NULL; } arenaobj->address = (uintptr_t)address; - ++_PyRuntime.mem.narenas_currently_allocated; - ++_PyRuntime.mem.ntimes_arena_allocated; - if (_PyRuntime.mem.narenas_currently_allocated > _PyRuntime.mem.narenas_highwater) - _PyRuntime.mem.narenas_highwater = _PyRuntime.mem.narenas_currently_allocated; + ++narenas_currently_allocated; + ++ntimes_arena_allocated; + if (narenas_currently_allocated > narenas_highwater) + narenas_highwater = narenas_currently_allocated; arenaobj->freepools = NULL; /* pool_address <- first pool-aligned address in the arena nfreepools <- number of whole pools that fit after alignment */ - arenaobj->pool_address = (pyblock*)arenaobj->address; + arenaobj->pool_address = (block*)arenaobj->address; arenaobj->nfreepools = ARENA_SIZE / POOL_SIZE; assert(POOL_SIZE * arenaobj->nfreepools == ARENA_SIZE); excess = (uint)(arenaobj->address & POOL_SIZE_MASK); @@ -753,9 +1212,9 @@ address_in_range(void *p, poolp pool) // the GIL. The following dance forces the compiler to read pool->arenaindex // only once. uint arenaindex = *((volatile uint *)&pool->arenaindex); - return arenaindex < _PyRuntime.mem.maxarenas && - (uintptr_t)p - _PyRuntime.mem.arenas[arenaindex].address < ARENA_SIZE && - _PyRuntime.mem.arenas[arenaindex].address != 0; + return arenaindex < maxarenas && + (uintptr_t)p - arenas[arenaindex].address < ARENA_SIZE && + arenas[arenaindex].address != 0; } @@ -777,7 +1236,7 @@ address_in_range(void *p, poolp pool) static int pymalloc_alloc(void *ctx, void **ptr_p, size_t nbytes) { - pyblock *bp; + block *bp; poolp pool; poolp next; uint size; @@ -803,7 +1262,7 @@ pymalloc_alloc(void *ctx, void **ptr_p, size_t nbytes) * Most frequent paths first */ size = (uint)(nbytes - 1) >> ALIGNMENT_SHIFT; - pool = _PyRuntime.mem.usedpools[size + size]; + pool = usedpools[size + size]; if (pool != pool->nextpool) { /* * There is a used pool for this size class. @@ -812,7 +1271,7 @@ pymalloc_alloc(void *ctx, void **ptr_p, size_t nbytes) ++pool->ref.count; bp = pool->freeblock; assert(bp != NULL); - if ((pool->freeblock = *(pyblock **)bp) != NULL) { + if ((pool->freeblock = *(block **)bp) != NULL) { goto success; } @@ -821,10 +1280,10 @@ pymalloc_alloc(void *ctx, void **ptr_p, size_t nbytes) */ if (pool->nextoffset <= pool->maxnextoffset) { /* There is room for another block. */ - pool->freeblock = (pyblock*)pool + + pool->freeblock = (block*)pool + pool->nextoffset; pool->nextoffset += INDEX2SIZE(size); - *(pyblock **)(pool->freeblock) = NULL; + *(block **)(pool->freeblock) = NULL; goto success; } @@ -839,27 +1298,27 @@ pymalloc_alloc(void *ctx, void **ptr_p, size_t nbytes) /* There isn't a pool of the right size class immediately * available: use a free pool. */ - if (_PyRuntime.mem.usable_arenas == NULL) { + if (usable_arenas == NULL) { /* No arena has a free pool: allocate a new arena. */ #ifdef WITH_MEMORY_LIMITS - if (_PyRuntime.mem.narenas_currently_allocated >= MAX_ARENAS) { + if (narenas_currently_allocated >= MAX_ARENAS) { goto failed; } #endif - _PyRuntime.mem.usable_arenas = new_arena(); - if (_PyRuntime.mem.usable_arenas == NULL) { + usable_arenas = new_arena(); + if (usable_arenas == NULL) { goto failed; } - _PyRuntime.mem.usable_arenas->nextarena = - _PyRuntime.mem.usable_arenas->prevarena = NULL; + usable_arenas->nextarena = + usable_arenas->prevarena = NULL; } - assert(_PyRuntime.mem.usable_arenas->address != 0); + assert(usable_arenas->address != 0); /* Try to get a cached free pool. */ - pool = _PyRuntime.mem.usable_arenas->freepools; + pool = usable_arenas->freepools; if (pool != NULL) { /* Unlink from cached pools. */ - _PyRuntime.mem.usable_arenas->freepools = pool->nextpool; + usable_arenas->freepools = pool->nextpool; /* This arena already had the smallest nfreepools * value, so decreasing nfreepools doesn't change @@ -868,18 +1327,18 @@ pymalloc_alloc(void *ctx, void **ptr_p, size_t nbytes) * become wholly allocated, we need to remove its * arena_object from usable_arenas. */ - --_PyRuntime.mem.usable_arenas->nfreepools; - if (_PyRuntime.mem.usable_arenas->nfreepools == 0) { + --usable_arenas->nfreepools; + if (usable_arenas->nfreepools == 0) { /* Wholly allocated: remove. */ - assert(_PyRuntime.mem.usable_arenas->freepools == NULL); - assert(_PyRuntime.mem.usable_arenas->nextarena == NULL || - _PyRuntime.mem.usable_arenas->nextarena->prevarena == - _PyRuntime.mem.usable_arenas); - - _PyRuntime.mem.usable_arenas = _PyRuntime.mem.usable_arenas->nextarena; - if (_PyRuntime.mem.usable_arenas != NULL) { - _PyRuntime.mem.usable_arenas->prevarena = NULL; - assert(_PyRuntime.mem.usable_arenas->address != 0); + assert(usable_arenas->freepools == NULL); + assert(usable_arenas->nextarena == NULL || + usable_arenas->nextarena->prevarena == + usable_arenas); + + usable_arenas = usable_arenas->nextarena; + if (usable_arenas != NULL) { + usable_arenas->prevarena = NULL; + assert(usable_arenas->address != 0); } } else { @@ -888,15 +1347,15 @@ pymalloc_alloc(void *ctx, void **ptr_p, size_t nbytes) * off all the arena's pools for the first * time. */ - assert(_PyRuntime.mem.usable_arenas->freepools != NULL || - _PyRuntime.mem.usable_arenas->pool_address <= - (pyblock*)_PyRuntime.mem.usable_arenas->address + + assert(usable_arenas->freepools != NULL || + usable_arenas->pool_address <= + (block*)usable_arenas->address + ARENA_SIZE - POOL_SIZE); } init_pool: /* Frontlink to used pools. */ - next = _PyRuntime.mem.usedpools[size + size]; /* == prev */ + next = usedpools[size + size]; /* == prev */ pool->nextpool = next; pool->prevpool = next; next->nextpool = pool; @@ -909,7 +1368,7 @@ pymalloc_alloc(void *ctx, void **ptr_p, size_t nbytes) */ bp = pool->freeblock; assert(bp != NULL); - pool->freeblock = *(pyblock **)bp; + pool->freeblock = *(block **)bp; goto success; } /* @@ -919,35 +1378,35 @@ pymalloc_alloc(void *ctx, void **ptr_p, size_t nbytes) */ pool->szidx = size; size = INDEX2SIZE(size); - bp = (pyblock *)pool + POOL_OVERHEAD; + bp = (block *)pool + POOL_OVERHEAD; pool->nextoffset = POOL_OVERHEAD + (size << 1); pool->maxnextoffset = POOL_SIZE - size; pool->freeblock = bp + size; - *(pyblock **)(pool->freeblock) = NULL; + *(block **)(pool->freeblock) = NULL; goto success; } /* Carve off a new pool. */ - assert(_PyRuntime.mem.usable_arenas->nfreepools > 0); - assert(_PyRuntime.mem.usable_arenas->freepools == NULL); - pool = (poolp)_PyRuntime.mem.usable_arenas->pool_address; - assert((pyblock*)pool <= (pyblock*)_PyRuntime.mem.usable_arenas->address + + assert(usable_arenas->nfreepools > 0); + assert(usable_arenas->freepools == NULL); + pool = (poolp)usable_arenas->pool_address; + assert((block*)pool <= (block*)usable_arenas->address + ARENA_SIZE - POOL_SIZE); - pool->arenaindex = (uint)(_PyRuntime.mem.usable_arenas - _PyRuntime.mem.arenas); - assert(&_PyRuntime.mem.arenas[pool->arenaindex] == _PyRuntime.mem.usable_arenas); + pool->arenaindex = (uint)(usable_arenas - arenas); + assert(&arenas[pool->arenaindex] == usable_arenas); pool->szidx = DUMMY_SIZE_IDX; - _PyRuntime.mem.usable_arenas->pool_address += POOL_SIZE; - --_PyRuntime.mem.usable_arenas->nfreepools; + usable_arenas->pool_address += POOL_SIZE; + --usable_arenas->nfreepools; - if (_PyRuntime.mem.usable_arenas->nfreepools == 0) { - assert(_PyRuntime.mem.usable_arenas->nextarena == NULL || - _PyRuntime.mem.usable_arenas->nextarena->prevarena == - _PyRuntime.mem.usable_arenas); + if (usable_arenas->nfreepools == 0) { + assert(usable_arenas->nextarena == NULL || + usable_arenas->nextarena->prevarena == + usable_arenas); /* Unlink the arena: it is completely allocated. */ - _PyRuntime.mem.usable_arenas = _PyRuntime.mem.usable_arenas->nextarena; - if (_PyRuntime.mem.usable_arenas != NULL) { - _PyRuntime.mem.usable_arenas->prevarena = NULL; - assert(_PyRuntime.mem.usable_arenas->address != 0); + usable_arenas = usable_arenas->nextarena; + if (usable_arenas != NULL) { + usable_arenas->prevarena = NULL; + assert(usable_arenas->address != 0); } } @@ -970,13 +1429,13 @@ _PyObject_Malloc(void *ctx, size_t nbytes) { void* ptr; if (pymalloc_alloc(ctx, &ptr, nbytes)) { - _PyRuntime.mem.num_allocated_blocks++; + _Py_AllocatedBlocks++; return ptr; } ptr = PyMem_RawMalloc(nbytes); if (ptr != NULL) { - _PyRuntime.mem.num_allocated_blocks++; + _Py_AllocatedBlocks++; } return ptr; } @@ -992,13 +1451,13 @@ _PyObject_Calloc(void *ctx, size_t nelem, size_t elsize) if (pymalloc_alloc(ctx, &ptr, nbytes)) { memset(ptr, 0, nbytes); - _PyRuntime.mem.num_allocated_blocks++; + _Py_AllocatedBlocks++; return ptr; } ptr = PyMem_RawCalloc(nelem, elsize); if (ptr != NULL) { - _PyRuntime.mem.num_allocated_blocks++; + _Py_AllocatedBlocks++; } return ptr; } @@ -1011,7 +1470,7 @@ static int pymalloc_free(void *ctx, void *p) { poolp pool; - pyblock *lastfree; + block *lastfree; poolp next, prev; uint size; @@ -1038,8 +1497,8 @@ pymalloc_free(void *ctx, void *p) * list in any case). */ assert(pool->ref.count > 0); /* else it was empty */ - *(pyblock **)p = lastfree = pool->freeblock; - pool->freeblock = (pyblock *)p; + *(block **)p = lastfree = pool->freeblock; + pool->freeblock = (block *)p; if (!lastfree) { /* Pool was full, so doesn't currently live in any list: * link it to the front of the appropriate usedpools[] list. @@ -1050,7 +1509,7 @@ pymalloc_free(void *ctx, void *p) --pool->ref.count; assert(pool->ref.count > 0); /* else the pool is empty */ size = pool->szidx; - next = _PyRuntime.mem.usedpools[size + size]; + next = usedpools[size + size]; prev = next->prevpool; /* insert pool before next: prev <-> pool <-> next */ @@ -1084,7 +1543,7 @@ pymalloc_free(void *ctx, void *p) /* Link the pool to freepools. This is a singly-linked * list, and pool->prevpool isn't used there. */ - ao = &_PyRuntime.mem.arenas[pool->arenaindex]; + ao = &arenas[pool->arenaindex]; pool->nextpool = ao->freepools; ao->freepools = pool; nf = ++ao->nfreepools; @@ -1113,9 +1572,9 @@ pymalloc_free(void *ctx, void *p) * usable_arenas pointer. */ if (ao->prevarena == NULL) { - _PyRuntime.mem.usable_arenas = ao->nextarena; - assert(_PyRuntime.mem.usable_arenas == NULL || - _PyRuntime.mem.usable_arenas->address != 0); + usable_arenas = ao->nextarena; + assert(usable_arenas == NULL || + usable_arenas->address != 0); } else { assert(ao->prevarena->nextarena == ao); @@ -1131,14 +1590,14 @@ pymalloc_free(void *ctx, void *p) /* Record that this arena_object slot is * available to be reused. */ - ao->nextarena = _PyRuntime.mem.unused_arena_objects; - _PyRuntime.mem.unused_arena_objects = ao; + ao->nextarena = unused_arena_objects; + unused_arena_objects = ao; /* Free the entire arena. */ - _PyRuntime.obj.allocator_arenas.free(_PyRuntime.obj.allocator_arenas.ctx, + _PyObject_Arena.free(_PyObject_Arena.ctx, (void *)ao->address, ARENA_SIZE); ao->address = 0; /* mark unassociated */ - --_PyRuntime.mem.narenas_currently_allocated; + --narenas_currently_allocated; goto success; } @@ -1149,12 +1608,12 @@ pymalloc_free(void *ctx, void *p) * ao->nfreepools was 0 before, ao isn't * currently on the usable_arenas list. */ - ao->nextarena = _PyRuntime.mem.usable_arenas; + ao->nextarena = usable_arenas; ao->prevarena = NULL; - if (_PyRuntime.mem.usable_arenas) - _PyRuntime.mem.usable_arenas->prevarena = ao; - _PyRuntime.mem.usable_arenas = ao; - assert(_PyRuntime.mem.usable_arenas->address != 0); + if (usable_arenas) + usable_arenas->prevarena = ao; + usable_arenas = ao; + assert(usable_arenas->address != 0); goto success; } @@ -1183,8 +1642,8 @@ pymalloc_free(void *ctx, void *p) } else { /* ao is at the head of the list */ - assert(_PyRuntime.mem.usable_arenas == ao); - _PyRuntime.mem.usable_arenas = ao->nextarena; + assert(usable_arenas == ao); + usable_arenas = ao->nextarena; } ao->nextarena->prevarena = ao->prevarena; @@ -1209,7 +1668,7 @@ pymalloc_free(void *ctx, void *p) assert(ao->nextarena == NULL || nf <= ao->nextarena->nfreepools); assert(ao->prevarena == NULL || nf > ao->prevarena->nfreepools); assert(ao->nextarena == NULL || ao->nextarena->prevarena == ao); - assert((_PyRuntime.mem.usable_arenas == ao && ao->prevarena == NULL) + assert((usable_arenas == ao && ao->prevarena == NULL) || ao->prevarena->nextarena == ao); goto success; @@ -1228,7 +1687,7 @@ _PyObject_Free(void *ctx, void *p) return; } - _PyRuntime.mem.num_allocated_blocks--; + _Py_AllocatedBlocks--; if (!pymalloc_free(ctx, p)) { /* pymalloc didn't allocate this address */ PyMem_RawFree(p); @@ -1353,13 +1812,15 @@ _Py_GetAllocatedBlocks(void) #define DEADBYTE 0xDB /* dead (newly freed) memory */ #define FORBIDDENBYTE 0xFB /* untouchable bytes at each end of a block */ +static size_t serialno = 0; /* incremented on each debug {m,re}alloc */ + /* serialno is always incremented via calling this routine. The point is * to supply a single place to set a breakpoint. */ static void bumpserialno(void) { - ++_PyRuntime.mem.serialno; + ++serialno; } #define SST SIZEOF_SIZE_T @@ -1466,7 +1927,7 @@ _PyMem_DebugRawAlloc(int use_calloc, void *ctx, size_t nbytes) /* at tail, write pad (SST bytes) and serialno (SST bytes) */ tail = data + nbytes; memset(tail, FORBIDDENBYTE, SST); - write_size_t(tail + SST, _PyRuntime.mem.serialno); + write_size_t(tail + SST, serialno); return data; } @@ -1526,7 +1987,7 @@ _PyMem_DebugRawRealloc(void *ctx, void *p, size_t nbytes) uint8_t *tail; /* data + nbytes == pointer to tail pad bytes */ size_t total; /* 2 * SST + nbytes + 2 * SST */ size_t original_nbytes; - size_t serialno; + size_t block_serialno; #define ERASED_SIZE 64 uint8_t save[2*ERASED_SIZE]; /* A copy of erased bytes. */ @@ -1542,7 +2003,7 @@ _PyMem_DebugRawRealloc(void *ctx, void *p, size_t nbytes) total = nbytes + 4*SST; tail = data + original_nbytes; - serialno = read_size_t(tail + SST); + block_serialno = read_size_t(tail + SST); /* Mark the header, the trailer, ERASED_SIZE bytes at the begin and ERASED_SIZE bytes at the end as dead and save the copy of erased bytes. */ @@ -1565,7 +2026,7 @@ _PyMem_DebugRawRealloc(void *ctx, void *p, size_t nbytes) else { head = r; bumpserialno(); - serialno = _PyRuntime.mem.serialno; + block_serialno = serialno; } write_size_t(head, nbytes); @@ -1575,7 +2036,7 @@ _PyMem_DebugRawRealloc(void *ctx, void *p, size_t nbytes) tail = data + nbytes; memset(tail, FORBIDDENBYTE, SST); - write_size_t(tail + SST, serialno); + write_size_t(tail + SST, block_serialno); /* Restore saved bytes. */ if (original_nbytes <= sizeof(save)) { @@ -1923,16 +2384,16 @@ _PyObject_DebugMallocStats(FILE *out) * to march over all the arenas. If we're lucky, most of the memory * will be living in full pools -- would be a shame to miss them. */ - for (i = 0; i < _PyRuntime.mem.maxarenas; ++i) { + for (i = 0; i < maxarenas; ++i) { uint j; - uintptr_t base = _PyRuntime.mem.arenas[i].address; + uintptr_t base = arenas[i].address; /* Skip arenas which are not allocated. */ - if (_PyRuntime.mem.arenas[i].address == (uintptr_t)NULL) + if (arenas[i].address == (uintptr_t)NULL) continue; narenas += 1; - numfreepools += _PyRuntime.mem.arenas[i].nfreepools; + numfreepools += arenas[i].nfreepools; /* round up to pool alignment */ if (base & (uintptr_t)POOL_SIZE_MASK) { @@ -1942,8 +2403,8 @@ _PyObject_DebugMallocStats(FILE *out) } /* visit every pool in the arena */ - assert(base <= (uintptr_t) _PyRuntime.mem.arenas[i].pool_address); - for (j = 0; base < (uintptr_t) _PyRuntime.mem.arenas[i].pool_address; + assert(base <= (uintptr_t) arenas[i].pool_address); + for (j = 0; base < (uintptr_t) arenas[i].pool_address; ++j, base += POOL_SIZE) { poolp p = (poolp)base; const uint sz = p->szidx; @@ -1952,7 +2413,7 @@ _PyObject_DebugMallocStats(FILE *out) if (p->ref.count == 0) { /* currently unused */ #ifdef Py_DEBUG - assert(pool_is_in_list(p, _PyRuntime.mem.arenas[i].freepools)); + assert(pool_is_in_list(p, arenas[i].freepools)); #endif continue; } @@ -1962,11 +2423,11 @@ _PyObject_DebugMallocStats(FILE *out) numfreeblocks[sz] += freeblocks; #ifdef Py_DEBUG if (freeblocks > 0) - assert(pool_is_in_list(p, _PyRuntime.mem.usedpools[sz + sz])); + assert(pool_is_in_list(p, usedpools[sz + sz])); #endif } } - assert(narenas == _PyRuntime.mem.narenas_currently_allocated); + assert(narenas == narenas_currently_allocated); fputc('\n', out); fputs("class size num pools blocks in use avail blocks\n" @@ -1994,10 +2455,10 @@ _PyObject_DebugMallocStats(FILE *out) } fputc('\n', out); if (_PyMem_DebugEnabled()) - (void)printone(out, "# times object malloc called", _PyRuntime.mem.serialno); - (void)printone(out, "# arenas allocated total", _PyRuntime.mem.ntimes_arena_allocated); - (void)printone(out, "# arenas reclaimed", _PyRuntime.mem.ntimes_arena_allocated - narenas); - (void)printone(out, "# arenas highwater mark", _PyRuntime.mem.narenas_highwater); + (void)printone(out, "# times object malloc called", serialno); + (void)printone(out, "# arenas allocated total", ntimes_arena_allocated); + (void)printone(out, "# arenas reclaimed", ntimes_arena_allocated - narenas); + (void)printone(out, "# arenas highwater mark", narenas_highwater); (void)printone(out, "# arenas allocated current", narenas); PyOS_snprintf(buf, sizeof(buf), diff --git a/PCbuild/pythoncore.vcxproj b/PCbuild/pythoncore.vcxproj index 246de78..3793cbd 100644 --- a/PCbuild/pythoncore.vcxproj +++ b/PCbuild/pythoncore.vcxproj @@ -116,7 +116,6 @@ - diff --git a/PCbuild/pythoncore.vcxproj.filters b/PCbuild/pythoncore.vcxproj.filters index b37e993..1d33c6e 100644 --- a/PCbuild/pythoncore.vcxproj.filters +++ b/PCbuild/pythoncore.vcxproj.filters @@ -141,9 +141,6 @@ Include - - Include - Include @@ -1031,4 +1028,4 @@ Resource Files - \ No newline at end of file + diff --git a/Parser/pgenmain.c b/Parser/pgenmain.c index dbdf134..20ef8a7 100644 --- a/Parser/pgenmain.c +++ b/Parser/pgenmain.c @@ -60,8 +60,6 @@ main(int argc, char **argv) filename = argv[1]; graminit_h = argv[2]; graminit_c = argv[3]; - _PyObject_Initialize(&_PyRuntime.obj); - _PyMem_Initialize(&_PyRuntime.mem); g = getgrammar(filename); fp = fopen(graminit_c, "w"); if (fp == NULL) { diff --git a/Programs/_testembed.c b/Programs/_testembed.c index e68e68d..52a0b51 100644 --- a/Programs/_testembed.c +++ b/Programs/_testembed.c @@ -125,6 +125,28 @@ static int test_forced_io_encoding(void) return 0; } + +/********************************************************* + * Test parts of the C-API that work before initialization + *********************************************************/ + +static int test_pre_initialization_api(void) +{ + wchar_t *program = Py_DecodeLocale("spam", NULL); + if (program == NULL) { + fprintf(stderr, "Fatal error: cannot decode program name\n"); + return 1; + } + Py_SetProgramName(program); + + Py_Initialize(); + Py_Finalize(); + + PyMem_RawFree(program); + return 0; +} + + /* ********************************************************* * List of test cases and the function that implements it. * @@ -146,6 +168,7 @@ struct TestCase static struct TestCase TestCases[] = { { "forced_io_encoding", test_forced_io_encoding }, { "repeated_init_and_subinterpreters", test_repeated_init_and_subinterpreters }, + { "pre_initialization_api", test_pre_initialization_api }, { NULL, NULL } }; diff --git a/Python/pystate.c b/Python/pystate.c index f6fbb4d..ecf921d 100644 --- a/Python/pystate.c +++ b/Python/pystate.c @@ -40,8 +40,6 @@ _PyRuntimeState_Init(_PyRuntimeState *runtime) { memset(runtime, 0, sizeof(*runtime)); - _PyObject_Initialize(&runtime->obj); - _PyMem_Initialize(&runtime->mem); _PyGC_Initialize(&runtime->gc); _PyEval_Initialize(&runtime->ceval); -- cgit v0.12