| #include "Python.h" |
| |
| #ifdef WITH_PYMALLOC |
| |
| /* An object allocator for Python. |
| |
| Here is an introduction to the layers of the Python memory architecture, |
| showing where the object allocator is actually used (layer +2), It is |
| called for every object allocation and deallocation (PyObject_New/Del), |
| unless the object-specific allocators implement a proprietary allocation |
| scheme (ex.: ints use a simple free list). This is also the place where |
| the cyclic garbage collector operates selectively on container objects. |
| |
| |
| Object-specific allocators |
| _____ ______ ______ ________ |
| [ int ] [ dict ] [ list ] ... [ string ] Python core | |
| +3 | <----- Object-specific memory -----> | <-- Non-object memory --> | |
| _______________________________ | | |
| [ Python's object allocator ] | | |
| +2 | ####### Object memory ####### | <------ Internal buffers ------> | |
| ______________________________________________________________ | |
| [ Python's raw memory allocator (PyMem_ API) ] | |
| +1 | <----- Python memory (under PyMem manager's control) ------> | | |
| __________________________________________________________________ |
| [ Underlying general-purpose allocator (ex: C library malloc) ] |
| 0 | <------ Virtual memory allocated for the python process -------> | |
| |
| ========================================================================= |
| _______________________________________________________________________ |
| [ OS-specific Virtual Memory Manager (VMM) ] |
| -1 | <--- Kernel dynamic storage allocation & management (page-based) ---> | |
| __________________________________ __________________________________ |
| [ ] [ ] |
| -2 | <-- Physical memory: ROM/RAM --> | | <-- Secondary storage (swap) --> | |
| |
| */ |
| /*==========================================================================*/ |
| |
| /* A fast, special-purpose memory allocator for small blocks, to be used |
| on top of a general-purpose malloc -- heavily based on previous art. */ |
| |
| /* Vladimir Marangozov -- August 2000 */ |
| |
| /* |
| * "Memory management is where the rubber meets the road -- if we do the wrong |
| * thing at any level, the results will not be good. And if we don't make the |
| * levels work well together, we are in serious trouble." (1) |
| * |
| * (1) Paul R. Wilson, Mark S. Johnstone, Michael Neely, and David Boles, |
| * "Dynamic Storage Allocation: A Survey and Critical Review", |
| * in Proc. 1995 Int'l. Workshop on Memory Management, September 1995. |
| */ |
| |
| /* #undef WITH_MEMORY_LIMITS */ /* disable mem limit checks */ |
| |
| /*==========================================================================*/ |
| |
| /* |
| * Allocation strategy abstract: |
| * |
| * For small requests, the allocator sub-allocates <Big> blocks of memory. |
| * Requests greater than 256 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 |
| * ... ... ... |
| * 241-248 248 30 |
| * 249-256 256 31 |
| * |
| * 0, 257 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 |
| #define ALIGNMENT_MASK (ALIGNMENT - 1) |
| |
| /* 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. |
| * |
| * The following invariants must hold: |
| * 1) ALIGNMENT <= SMALL_REQUEST_THRESHOLD <= 256 |
| * 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 256 |
| #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. |
| */ |
| #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 <Big> blocks of memory (called arenas) aligned |
| * on a page boundary. This is a reserved virtual address space for the |
| * current process (obtained through a malloc call). In no way this means |
| * that the memory arenas will be used entirely. A malloc(<Big>) is usually |
| * an address range reservation for <Big> bytes, unless all pages within this |
| * space are referenced subsequently. So malloc'ing big blocks and not using |
| * them does not mean "wasting memory". It's an addressable range wastage... |
| * |
| * Therefore, allocating arenas with malloc is not optimal, because there is |
| * some address space wastage, but this is the most portable way to request |
| * memory from the system across various platforms. |
| */ |
| #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 */ |
| |
| /* |
| * Basic types |
| * I don't care if these are defined in <sys/types.h> or elsewhere. Axiom. |
| */ |
| #undef uchar |
| #define uchar unsigned char /* assuming == 8 bits */ |
| |
| #undef uint |
| #define uint unsigned int /* assuming >= 16 bits */ |
| |
| #undef ulong |
| #define ulong unsigned long /* assuming >= 32 bits */ |
| |
| #undef uptr |
| #define uptr Py_uintptr_t |
| |
| /* When you say memory, my mind reasons in terms of (pointers to) blocks */ |
| typedef uchar 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; |
| |
| #undef ROUNDUP |
| #define ROUNDUP(x) (((x) + ALIGNMENT_MASK) & ~ALIGNMENT_MASK) |
| #define POOL_OVERHEAD ROUNDUP(sizeof(struct pool_header)) |
| |
| #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)((uptr)(P) & ~(uptr)POOL_SIZE_MASK)) |
| |
| /* 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)<<ALIGNMENT_SHIFT. |
| |
| Pools are carved off the current arena highwater mark (file static arenabase) |
| as needed. Once carved off, a pool is in one of three states forever after: |
| |
| used == partially used, neither empty nor full |
| At least one block in the pool is currently allocated, and at least one |
| block in the pool is not currently allocated (note this implies a pool |
| has room for at least two blocks). |
| This is a pool's initial state, as a pool is created only when malloc |
| needs space. |
| The pool holds blocks of a fixed size, and is in the circular list headed |
| at usedpools[i] (see above). It's linked to the other used pools of the |
| same size class via the pool_header's nextpool and prevpool members. |
| If all but one block is currently allocated, a malloc can cause a |
| transition to the full state. If all but one block is not currently |
| allocated, a free can cause a transition to the empty state. |
| |
| full == all the pool's blocks are currently allocated |
| On transition to full, a pool is unlinked from its usedpools[] list. |
| It's not linked to from anything then anymore, and its nextpool and |
| prevpool members are meaningless until it transitions back to used. |
| A free of a block in a full pool puts the pool back in the used state. |
| Then it's linked in at the front of the appropriate usedpools[] list, so |
| that the next allocation for its size class will reuse the freed block. |
| |
| empty == all the pool's blocks are currently available for allocation |
| On transition to empty, a pool is unlinked from its usedpools[] list, |
| and linked to the front of the (file static) singly-linked freepools list, |
| via its nextpool member. The prevpool member has no meaning in this case. |
| Empty pools have no inherent size class: the next time a malloc finds |
| an empty list in usedpools[], it takes the first pool off of freepools. |
| If the size class needed happens to be the same as the size class the pool |
| last had, some pool initialization can be skipped. |
| |
| |
| Block Management |
| |
| Blocks within pools are again carved out as needed. pool->freeblock points to |
| the start of a singly-linked list of free blocks within the pool. When a |
| block is freed, it's inserted at the front of its pool's freeblock list. Note |
| that the available blocks in a pool are *not* linked all together when a pool |
| is initialized. Instead only "the first two" (lowest addresses) blocks are |
| set up, returning the first such block, and setting pool->freeblock to a |
| one-block list holding the second such block. This is consistent with that |
| pymalloc strives at all levels (arena, pool, and block) never to touch a piece |
| of memory until it's actually needed. |
| |
| So long as a pool is in the used state, we're certain there *is* a block |
| available for allocating, and pool->freeblock is not NULL. If pool->freeblock |
| points to the end of the free list before we've carved the entire pool into |
| blocks, that means we simply haven't yet gotten to one of the higher-address |
| blocks. The offset from the pool_header to the start of "the next" virgin |
| block is stored in the pool_header nextoffset member, and the largest value |
| of nextoffset that makes sense is stored in the maxnextoffset member when a |
| pool is initialized. All the blocks in a pool have been passed out at least |
| once when and only when nextoffset > maxnextoffset. |
| |
| |
| Major obscurity: While the usedpools vector is declared to have poolp |
| entries, it doesn't really. It really contains two pointers per (conceptual) |
| poolp entry, the nextpool and prevpool members of a pool_header. The |
| excruciating initialization code below fools C so that |
| |
| usedpool[i+i] |
| |
| "acts like" a genuine poolp, but only so long as you only reference its |
| nextpool and prevpool members. The "- 2*sizeof(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 )((uchar *)&(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) |
| #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 */ |
| }; |
| |
| /* |
| * Free (cached) pools |
| */ |
| static poolp freepools = NULL; /* free list for cached pools */ |
| |
| /*==========================================================================*/ |
| /* Arena management. */ |
| |
| /* arenas is a vector of arena base addresses, in order of allocation time. |
| * arenas currently contains narenas entries, and has space allocated |
| * for at most maxarenas entries. |
| * |
| * CAUTION: See the long comment block about thread safety in new_arena(): |
| * the code currently relies in deep ways on that this vector only grows, |
| * and only grows by appending at the end. For now we never return an arena |
| * to the OS. |
| */ |
| static uptr *volatile arenas = NULL; /* the pointer itself is volatile */ |
| static volatile uint narenas = 0; |
| static uint maxarenas = 0; |
| |
| /* Number of pools still available to be allocated in the current arena. */ |
| static uint nfreepools = 0; |
| |
| /* Free space start address in current arena. This is pool-aligned. */ |
| static block *arenabase = NULL; |
| |
| /* Allocate a new arena and return its base address. If we run out of |
| * memory, return NULL. |
| */ |
| static block * |
| new_arena(void) |
| { |
| uint excess; /* number of bytes above pool alignment */ |
| block *bp = (block *)malloc(ARENA_SIZE); |
| if (bp == NULL) |
| return NULL; |
| |
| #ifdef PYMALLOC_DEBUG |
| if (Py_GETENV("PYTHONMALLOCSTATS")) |
| _PyObject_DebugMallocStats(); |
| #endif |
| |
| /* arenabase <- first pool-aligned address in the arena |
| nfreepools <- number of whole pools that fit after alignment */ |
| arenabase = bp; |
| nfreepools = ARENA_SIZE / POOL_SIZE; |
| assert(POOL_SIZE * nfreepools == ARENA_SIZE); |
| excess = (uint)bp & POOL_SIZE_MASK; |
| if (excess != 0) { |
| --nfreepools; |
| arenabase += POOL_SIZE - excess; |
| } |
| |
| /* Make room for a new entry in the arenas vector. */ |
| if (arenas == NULL) { |
| assert(narenas == 0 && maxarenas == 0); |
| arenas = (uptr *)malloc(16 * sizeof(*arenas)); |
| if (arenas == NULL) |
| goto error; |
| maxarenas = 16; |
| } |
| else if (narenas == maxarenas) { |
| /* Grow arenas. |
| * |
| * Exceedingly subtle: Someone may be calling the pymalloc |
| * free via PyMem_{DEL, Del, FREE, Free} without holding the |
| *.GIL. Someone else may simultaneously be calling the |
| * pymalloc malloc while holding the GIL via, e.g., |
| * PyObject_New. Now the pymalloc free may index into arenas |
| * for an address check, while the pymalloc malloc calls |
| * new_arena and we end up here to grow a new arena *and* |
| * grow the arenas vector. If the value for arenas pymalloc |
| * free picks up "vanishes" during this resize, anything may |
| * happen, and it would be an incredibly rare bug. Therefore |
| * the code here takes great pains to make sure that, at every |
| * moment, arenas always points to an intact vector of |
| * addresses. It doesn't matter whether arenas points to a |
| * wholly up-to-date vector when pymalloc free checks it in |
| * this case, because the only legal (and that even this is |
| * legal is debatable) way to call PyMem_{Del, etc} while not |
| * holding the GIL is if the memory being released is not |
| * object memory, i.e. if the address check in pymalloc free |
| * is supposed to fail. Having an incomplete vector can't |
| * make a supposed-to-fail case succeed by mistake (it could |
| * only make a supposed-to-succeed case fail by mistake). |
| * |
| * In addition, without a lock we can't know for sure when |
| * an old vector is no longer referenced, so we simply let |
| * old vectors leak. |
| * |
| * And on top of that, since narenas and arenas can't be |
| * changed as-a-pair atomically without a lock, we're also |
| * careful to declare them volatile and ensure that we change |
| * arenas first. This prevents another thread from picking |
| * up an narenas value too large for the arenas value it |
| * reads up (arenas never shrinks). |
| * |
| * Read the above 50 times before changing anything in this |
| * block. |
| */ |
| uptr *p; |
| uint newmax = maxarenas << 1; |
| if (newmax <= maxarenas) /* overflow */ |
| goto error; |
| p = (uptr *)malloc(newmax * sizeof(*arenas)); |
| if (p == NULL) |
| goto error; |
| memcpy(p, arenas, narenas * sizeof(*arenas)); |
| arenas = p; /* old arenas deliberately leaked */ |
| maxarenas = newmax; |
| } |
| |
| /* Append the new arena address to arenas. */ |
| assert(narenas < maxarenas); |
| arenas[narenas] = (uptr)bp; |
| ++narenas; /* can't overflow, since narenas < maxarenas before */ |
| return bp; |
| |
| error: |
| free(bp); |
| nfreepools = 0; |
| return NULL; |
| } |
| |
| /* Return true if and only if P is an address that was allocated by |
| * pymalloc. I must be the index into arenas that the address claims |
| * to come from. |
| * |
| * Tricky: Letting B be the arena base address in arenas[I], P belongs to the |
| * arena if and only if |
| * B <= P < B + ARENA_SIZE |
| * Subtracting B throughout, this is true iff |
| * 0 <= P-B < ARENA_SIZE |
| * By using unsigned arithmetic, the "0 <=" half of the test can be skipped. |
| * |
| * Obscure: A PyMem "free memory" function can call the pymalloc free or |
| * realloc before the first arena has been allocated. arenas is still |
| * NULL in that case. We're relying on that narenas is also 0 in that case, |
| * so the (I) < narenas must be false, saving us from trying to index into |
| * a NULL arenas. |
| */ |
| #define ADDRESS_IN_RANGE(P, I) \ |
| ((I) < narenas && (uptr)(P) - arenas[I] < (uptr)ARENA_SIZE) |
| |
| /*==========================================================================*/ |
| |
| /* malloc. Note that nbytes==0 tries to return a non-NULL pointer, distinct |
| * from all other currently live pointers. This may not be possible. |
| */ |
| |
| /* |
| * The basic blocks are ordered by decreasing execution frequency, |
| * which minimizes the number of jumps in the most common cases, |
| * improves branching prediction and instruction scheduling (small |
| * block allocations typically result in a couple of instructions). |
| * Unless the optimizer reorders everything, being too smart... |
| */ |
| |
| #undef PyObject_Malloc |
| void * |
| PyObject_Malloc(size_t nbytes) |
| { |
| block *bp; |
| poolp pool; |
| poolp next; |
| uint size; |
| |
| /* |
| * This implicitly redirects malloc(0). |
| */ |
| if ((nbytes - 1) < SMALL_REQUEST_THRESHOLD) { |
| LOCK(); |
| /* |
| * Most frequent paths first |
| */ |
| size = (uint )(nbytes - 1) >> ALIGNMENT_SHIFT; |
| pool = usedpools[size + size]; |
| if (pool != pool->nextpool) { |
| /* |
| * There is a used pool for this size class. |
| * Pick up the head block of its free list. |
| */ |
| ++pool->ref.count; |
| bp = pool->freeblock; |
| assert(bp != NULL); |
| if ((pool->freeblock = *(block **)bp) != NULL) { |
| UNLOCK(); |
| return (void *)bp; |
| } |
| /* |
| * Reached the end of the free list, try to extend it |
| */ |
| if (pool->nextoffset <= pool->maxnextoffset) { |
| /* |
| * There is room for another block |
| */ |
| pool->freeblock = (block *)pool + |
| pool->nextoffset; |
| pool->nextoffset += INDEX2SIZE(size); |
| *(block **)(pool->freeblock) = NULL; |
| UNLOCK(); |
| return (void *)bp; |
| } |
| /* |
| * Pool is full, unlink from used pools |
| */ |
| next = pool->nextpool; |
| pool = pool->prevpool; |
| next->prevpool = pool; |
| pool->nextpool = next; |
| UNLOCK(); |
| return (void *)bp; |
| } |
| /* |
| * Try to get a cached free pool |
| */ |
| pool = freepools; |
| if (pool != NULL) { |
| /* |
| * Unlink from cached pools |
| */ |
| freepools = pool->nextpool; |
| init_pool: |
| /* |
| * Frontlink to used pools |
| */ |
| next = usedpools[size + size]; /* == prev */ |
| pool->nextpool = next; |
| pool->prevpool = next; |
| next->nextpool = pool; |
| next->prevpool = pool; |
| pool->ref.count = 1; |
| if (pool->szidx == size) { |
| /* |
| * Luckily, this pool last contained blocks |
| * of the same size class, so its header |
| * and free list are already initialized. |
| */ |
| bp = pool->freeblock; |
| pool->freeblock = *(block **)bp; |
| UNLOCK(); |
| return (void *)bp; |
| } |
| /* |
| * Initialize the pool header, set up the free list to |
| * contain just the second block, and return the first |
| * block. |
| */ |
| pool->szidx = size; |
| size = INDEX2SIZE(size); |
| bp = (block *)pool + POOL_OVERHEAD; |
| pool->nextoffset = POOL_OVERHEAD + (size << 1); |
| pool->maxnextoffset = POOL_SIZE - size; |
| pool->freeblock = bp + size; |
| *(block **)(pool->freeblock) = NULL; |
| UNLOCK(); |
| return (void *)bp; |
| } |
| /* |
| * Allocate new pool |
| */ |
| if (nfreepools) { |
| commit_pool: |
| --nfreepools; |
| pool = (poolp)arenabase; |
| arenabase += POOL_SIZE; |
| pool->arenaindex = narenas - 1; |
| pool->szidx = DUMMY_SIZE_IDX; |
| goto init_pool; |
| } |
| /* |
| * Allocate new arena |
| */ |
| #ifdef WITH_MEMORY_LIMITS |
| if (!(narenas < MAX_ARENAS)) { |
| UNLOCK(); |
| goto redirect; |
| } |
| #endif |
| bp = new_arena(); |
| if (bp != NULL) |
| goto commit_pool; |
| UNLOCK(); |
| goto redirect; |
| } |
| |
| /* The small block allocator ends here. */ |
| |
| redirect: |
| /* |
| * Redirect the original request to the underlying (libc) allocator. |
| * We jump here on bigger requests, on error in the code above (as a |
| * last chance to serve the request) or when the max memory limit |
| * has been reached. |
| */ |
| #ifdef MALLOC_ZERO_RETURNS_NULL |
| if (nbytes == 0) |
| nbytes = 1; |
| #endif |
| return (void *)malloc(nbytes); |
| } |
| |
| /* free */ |
| |
| #undef PyObject_Free |
| void |
| PyObject_Free(void *p) |
| { |
| poolp pool; |
| block *lastfree; |
| poolp next, prev; |
| uint size; |
| |
| if (p == NULL) /* free(NULL) has no effect */ |
| return; |
| |
| pool = POOL_ADDR(p); |
| if (ADDRESS_IN_RANGE(p, pool->arenaindex)) { |
| /* We allocated this address. */ |
| LOCK(); |
| /* |
| * Link p to the start of the pool's freeblock list. Since |
| * the pool had at least the p block outstanding, the pool |
| * wasn't empty (so it's already in a usedpools[] list, or |
| * was full and is in no list -- it's not in the freeblocks |
| * list in any case). |
| */ |
| assert(pool->ref.count > 0); /* else it was empty */ |
| *(block **)p = lastfree = pool->freeblock; |
| pool->freeblock = (block *)p; |
| if (lastfree) { |
| /* |
| * freeblock wasn't NULL, so the pool wasn't full, |
| * and the pool is in a usedpools[] list. |
| */ |
| if (--pool->ref.count != 0) { |
| /* pool isn't empty: leave it in usedpools */ |
| UNLOCK(); |
| return; |
| } |
| /* |
| * Pool is now empty: unlink from usedpools, and |
| * link to the front of freepools. This ensures that |
| * previously freed pools will be allocated later |
| * (being not referenced, they are perhaps paged out). |
| */ |
| next = pool->nextpool; |
| prev = pool->prevpool; |
| next->prevpool = prev; |
| prev->nextpool = next; |
| /* Link to freepools. This is a singly-linked list, |
| * and pool->prevpool isn't used there. |
| */ |
| pool->nextpool = freepools; |
| freepools = pool; |
| UNLOCK(); |
| return; |
| } |
| /* |
| * Pool was full, so doesn't currently live in any list: |
| * link it to the front of the appropriate usedpools[] list. |
| * This mimics LRU pool usage for new allocations and |
| * targets optimal filling when several pools contain |
| * blocks of the same size class. |
| */ |
| --pool->ref.count; |
| assert(pool->ref.count > 0); /* else the pool is empty */ |
| size = pool->szidx; |
| next = usedpools[size + size]; |
| prev = next->prevpool; |
| /* insert pool before next: prev <-> pool <-> next */ |
| pool->nextpool = next; |
| pool->prevpool = prev; |
| next->prevpool = pool; |
| prev->nextpool = pool; |
| UNLOCK(); |
| return; |
| } |
| |
| /* We didn't allocate this address. */ |
| free(p); |
| } |
| |
| /* realloc. If p is NULL, this acts like malloc(nbytes). Else if nbytes==0, |
| * then as the Python docs promise, we do not treat this like free(p), and |
| * return a non-NULL result. |
| */ |
| |
| #undef PyObject_Realloc |
| void * |
| PyObject_Realloc(void *p, size_t nbytes) |
| { |
| void *bp; |
| poolp pool; |
| uint size; |
| |
| if (p == NULL) |
| return PyObject_Malloc(nbytes); |
| |
| pool = POOL_ADDR(p); |
| if (ADDRESS_IN_RANGE(p, pool->arenaindex)) { |
| /* We're in charge of this block */ |
| size = INDEX2SIZE(pool->szidx); |
| if (size >= nbytes) |
| /* Don't bother if a smaller size was requested. */ |
| return p; |
| /* We need more memory. */ |
| assert(nbytes != 0); |
| bp = PyObject_Malloc(nbytes); |
| if (bp != NULL) { |
| memcpy(bp, p, size); |
| PyObject_Free(p); |
| } |
| return bp; |
| } |
| /* We're not managing this block. */ |
| if (nbytes <= SMALL_REQUEST_THRESHOLD) { |
| /* Take over this block -- ask for at least one byte so |
| * we really do take it over (PyObject_Malloc(0) goes to |
| * the system malloc). |
| */ |
| bp = PyObject_Malloc(nbytes ? nbytes : 1); |
| if (bp != NULL) { |
| memcpy(bp, p, nbytes); |
| free(p); |
| } |
| else if (nbytes == 0) { |
| /* Meet the doc's promise that nbytes==0 will |
| * never return a NULL pointer when p isn't NULL. |
| */ |
| bp = p; |
| } |
| |
| } |
| else { |
| assert(nbytes != 0); |
| bp = realloc(p, nbytes); |
| } |
| return bp; |
| } |
| |
| #else /* ! WITH_PYMALLOC */ |
| |
| /*==========================================================================*/ |
| /* pymalloc not enabled: Redirect the entry points to malloc. These will |
| * only be used by extensions that are compiled with pymalloc enabled. */ |
| |
| void * |
| PyObject_Malloc(size_t n) |
| { |
| return PyMem_MALLOC(n); |
| } |
| |
| void * |
| PyObject_Realloc(void *p, size_t n) |
| { |
| return PyMem_REALLOC(p, n); |
| } |
| |
| void |
| PyObject_Free(void *p) |
| { |
| PyMem_FREE(p); |
| } |
| #endif /* WITH_PYMALLOC */ |
| |
| #ifdef PYMALLOC_DEBUG |
| /*==========================================================================*/ |
| /* A x-platform debugging allocator. This doesn't manage memory directly, |
| * it wraps a real allocator, adding extra debugging info to the memory blocks. |
| */ |
| |
| /* Special bytes broadcast into debug memory blocks at appropriate times. |
| * Strings of these are unlikely to be valid addresses, floats, ints or |
| * 7-bit ASCII. |
| */ |
| #undef CLEANBYTE |
| #undef DEADBYTE |
| #undef FORBIDDENBYTE |
| #define CLEANBYTE 0xCB /* clean (newly allocated) memory */ |
| #define DEADBYTE 0xDB /* deed (newly freed) memory */ |
| #define FORBIDDENBYTE 0xFB /* untouchable bytes at each end of a block */ |
| |
| static ulong 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) |
| { |
| ++serialno; |
| } |
| |
| |
| /* Read 4 bytes at p as a big-endian ulong. */ |
| static ulong |
| read4(const void *p) |
| { |
| const uchar *q = (const uchar *)p; |
| return ((ulong)q[0] << 24) | |
| ((ulong)q[1] << 16) | |
| ((ulong)q[2] << 8) | |
| (ulong)q[3]; |
| } |
| |
| /* Write the 4 least-significant bytes of n as a big-endian unsigned int, |
| MSB at address p, LSB at p+3. */ |
| static void |
| write4(void *p, ulong n) |
| { |
| uchar *q = (uchar *)p; |
| q[0] = (uchar)((n >> 24) & 0xff); |
| q[1] = (uchar)((n >> 16) & 0xff); |
| q[2] = (uchar)((n >> 8) & 0xff); |
| q[3] = (uchar)( n & 0xff); |
| } |
| |
| #ifdef Py_DEBUG |
| /* Is target in the list? The list is traversed via the nextpool pointers. |
| * The list may be NULL-terminated, or circular. Return 1 if target is in |
| * list, else 0. |
| */ |
| static int |
| pool_is_in_list(const poolp target, poolp list) |
| { |
| poolp origlist = list; |
| assert(target != NULL); |
| if (list == NULL) |
| return 0; |
| do { |
| if (target == list) |
| return 1; |
| list = list->nextpool; |
| } while (list != NULL && list != origlist); |
| return 0; |
| } |
| |
| #else |
| #define pool_is_in_list(X, Y) 1 |
| |
| #endif /* Py_DEBUG */ |
| |
| /* The debug malloc asks for 16 extra bytes and fills them with useful stuff, |
| here calling the underlying malloc's result p: |
| |
| p[0:4] |
| Number of bytes originally asked for. 4-byte unsigned integer, |
| big-endian (easier to read in a memory dump). |
| p[4:8] |
| Copies of FORBIDDENBYTE. Used to catch under- writes and reads. |
| p[8:8+n] |
| The requested memory, filled with copies of CLEANBYTE. |
| Used to catch reference to uninitialized memory. |
| &p[8] is returned. Note that this is 8-byte aligned if pymalloc |
| handled the request itself. |
| p[8+n:8+n+4] |
| Copies of FORBIDDENBYTE. Used to catch over- writes and reads. |
| p[8+n+4:8+n+8] |
| A serial number, incremented by 1 on each call to _PyObject_DebugMalloc |
| and _PyObject_DebugRealloc. |
| 4-byte unsigned integer, big-endian. |
| If "bad memory" is detected later, the serial number gives an |
| excellent way to set a breakpoint on the next run, to capture the |
| instant at which this block was passed out. |
| */ |
| |
| void * |
| _PyObject_DebugMalloc(size_t nbytes) |
| { |
| uchar *p; /* base address of malloc'ed block */ |
| uchar *tail; /* p + 8 + nbytes == pointer to tail pad bytes */ |
| size_t total; /* nbytes + 16 */ |
| |
| bumpserialno(); |
| total = nbytes + 16; |
| if (total < nbytes || (total >> 31) > 1) { |
| /* overflow, or we can't represent it in 4 bytes */ |
| /* Obscure: can't do (total >> 32) != 0 instead, because |
| C doesn't define what happens for a right-shift of 32 |
| when size_t is a 32-bit type. At least C guarantees |
| size_t is an unsigned type. */ |
| return NULL; |
| } |
| |
| p = (uchar *)PyObject_Malloc(total); |
| if (p == NULL) |
| return NULL; |
| |
| write4(p, nbytes); |
| p[4] = p[5] = p[6] = p[7] = FORBIDDENBYTE; |
| |
| if (nbytes > 0) |
| memset(p+8, CLEANBYTE, nbytes); |
| |
| tail = p + 8 + nbytes; |
| tail[0] = tail[1] = tail[2] = tail[3] = FORBIDDENBYTE; |
| write4(tail + 4, serialno); |
| |
| return p+8; |
| } |
| |
| /* The debug free first checks the 8 bytes on each end for sanity (in |
| particular, that the FORBIDDENBYTEs are still intact). |
| Then fills the original bytes with DEADBYTE. |
| Then calls the underlying free. |
| */ |
| void |
| _PyObject_DebugFree(void *p) |
| { |
| uchar *q = (uchar *)p; |
| size_t nbytes; |
| |
| if (p == NULL) |
| return; |
| _PyObject_DebugCheckAddress(p); |
| nbytes = read4(q-8); |
| if (nbytes > 0) |
| memset(q, DEADBYTE, nbytes); |
| PyObject_Free(q-8); |
| } |
| |
| void * |
| _PyObject_DebugRealloc(void *p, size_t nbytes) |
| { |
| uchar *q = (uchar *)p; |
| uchar *tail; |
| size_t total; /* nbytes + 16 */ |
| size_t original_nbytes; |
| |
| if (p == NULL) |
| return _PyObject_DebugMalloc(nbytes); |
| |
| _PyObject_DebugCheckAddress(p); |
| bumpserialno(); |
| original_nbytes = read4(q-8); |
| total = nbytes + 16; |
| if (total < nbytes || (total >> 31) > 1) { |
| /* overflow, or we can't represent it in 4 bytes */ |
| return NULL; |
| } |
| |
| if (nbytes < original_nbytes) { |
| /* shrinking: mark old extra memory dead */ |
| memset(q + nbytes, DEADBYTE, original_nbytes - nbytes); |
| } |
| |
| /* Resize and add decorations. */ |
| q = (uchar *)PyObject_Realloc(q-8, total); |
| if (q == NULL) |
| return NULL; |
| |
| write4(q, nbytes); |
| assert(q[4] == FORBIDDENBYTE && |
| q[5] == FORBIDDENBYTE && |
| q[6] == FORBIDDENBYTE && |
| q[7] == FORBIDDENBYTE); |
| q += 8; |
| tail = q + nbytes; |
| tail[0] = tail[1] = tail[2] = tail[3] = FORBIDDENBYTE; |
| write4(tail + 4, serialno); |
| |
| if (nbytes > original_nbytes) { |
| /* growing: mark new extra memory clean */ |
| memset(q + original_nbytes, CLEANBYTE, |
| nbytes - original_nbytes); |
| } |
| |
| return q; |
| } |
| |
| /* Check the forbidden bytes on both ends of the memory allocated for p. |
| * If anything is wrong, print info to stderr via _PyObject_DebugDumpAddress, |
| * and call Py_FatalError to kill the program. |
| */ |
| void |
| _PyObject_DebugCheckAddress(const void *p) |
| { |
| const uchar *q = (const uchar *)p; |
| char *msg; |
| ulong nbytes; |
| const uchar *tail; |
| int i; |
| |
| if (p == NULL) { |
| msg = "didn't expect a NULL pointer"; |
| goto error; |
| } |
| |
| /* Check the stuff at the start of p first: if there's underwrite |
| * corruption, the number-of-bytes field may be nuts, and checking |
| * the tail could lead to a segfault then. |
| */ |
| for (i = 4; i >= 1; --i) { |
| if (*(q-i) != FORBIDDENBYTE) { |
| msg = "bad leading pad byte"; |
| goto error; |
| } |
| } |
| |
| nbytes = read4(q-8); |
| tail = q + nbytes; |
| for (i = 0; i < 4; ++i) { |
| if (tail[i] != FORBIDDENBYTE) { |
| msg = "bad trailing pad byte"; |
| goto error; |
| } |
| } |
| |
| return; |
| |
| error: |
| _PyObject_DebugDumpAddress(p); |
| Py_FatalError(msg); |
| } |
| |
| /* Display info to stderr about the memory block at p. */ |
| void |
| _PyObject_DebugDumpAddress(const void *p) |
| { |
| const uchar *q = (const uchar *)p; |
| const uchar *tail; |
| ulong nbytes, serial; |
| int i; |
| |
| fprintf(stderr, "Debug memory block at address p=%p:\n", p); |
| if (p == NULL) |
| return; |
| |
| nbytes = read4(q-8); |
| fprintf(stderr, " %lu bytes originally requested\n", nbytes); |
| |
| /* In case this is nuts, check the leading pad bytes first. */ |
| fputs(" The 4 pad bytes at p-4 are ", stderr); |
| if (*(q-4) == FORBIDDENBYTE && |
| *(q-3) == FORBIDDENBYTE && |
| *(q-2) == FORBIDDENBYTE && |
| *(q-1) == FORBIDDENBYTE) { |
| fputs("FORBIDDENBYTE, as expected.\n", stderr); |
| } |
| else { |
| fprintf(stderr, "not all FORBIDDENBYTE (0x%02x):\n", |
| FORBIDDENBYTE); |
| for (i = 4; i >= 1; --i) { |
| const uchar byte = *(q-i); |
| fprintf(stderr, " at p-%d: 0x%02x", i, byte); |
| if (byte != FORBIDDENBYTE) |
| fputs(" *** OUCH", stderr); |
| fputc('\n', stderr); |
| } |
| |
| fputs(" Because memory is corrupted at the start, the " |
| "count of bytes requested\n" |
| " may be bogus, and checking the trailing pad " |
| "bytes may segfault.\n", stderr); |
| } |
| |
| tail = q + nbytes; |
| fprintf(stderr, " The 4 pad bytes at tail=%p are ", tail); |
| if (tail[0] == FORBIDDENBYTE && |
| tail[1] == FORBIDDENBYTE && |
| tail[2] == FORBIDDENBYTE && |
| tail[3] == FORBIDDENBYTE) { |
| fputs("FORBIDDENBYTE, as expected.\n", stderr); |
| } |
| else { |
| fprintf(stderr, "not all FORBIDDENBYTE (0x%02x):\n", |
| FORBIDDENBYTE); |
| for (i = 0; i < 4; ++i) { |
| const uchar byte = tail[i]; |
| fprintf(stderr, " at tail+%d: 0x%02x", |
| i, byte); |
| if (byte != FORBIDDENBYTE) |
| fputs(" *** OUCH", stderr); |
| fputc('\n', stderr); |
| } |
| } |
| |
| serial = read4(tail+4); |
| fprintf(stderr, " The block was made by call #%lu to " |
| "debug malloc/realloc.\n", serial); |
| |
| if (nbytes > 0) { |
| int i = 0; |
| fputs(" Data at p:", stderr); |
| /* print up to 8 bytes at the start */ |
| while (q < tail && i < 8) { |
| fprintf(stderr, " %02x", *q); |
| ++i; |
| ++q; |
| } |
| /* and up to 8 at the end */ |
| if (q < tail) { |
| if (tail - q > 8) { |
| fputs(" ...", stderr); |
| q = tail - 8; |
| } |
| while (q < tail) { |
| fprintf(stderr, " %02x", *q); |
| ++q; |
| } |
| } |
| fputc('\n', stderr); |
| } |
| } |
| |
| static ulong |
| printone(const char* msg, ulong value) |
| { |
| int i, k; |
| char buf[100]; |
| ulong origvalue = value; |
| |
| fputs(msg, stderr); |
| for (i = (int)strlen(msg); i < 35; ++i) |
| fputc(' ', stderr); |
| fputc('=', stderr); |
| |
| /* Write the value with commas. */ |
| i = 22; |
| buf[i--] = '\0'; |
| buf[i--] = '\n'; |
| k = 3; |
| do { |
| ulong nextvalue = value / 10UL; |
| uint digit = value - nextvalue * 10UL; |
| value = nextvalue; |
| buf[i--] = (char)(digit + '0'); |
| --k; |
| if (k == 0 && value && i >= 0) { |
| k = 3; |
| buf[i--] = ','; |
| } |
| } while (value && i >= 0); |
| |
| while (i >= 0) |
| buf[i--] = ' '; |
| fputs(buf, stderr); |
| |
| return origvalue; |
| } |
| |
| /* Print summary info to stderr about the state of pymalloc's structures. |
| * In Py_DEBUG mode, also perform some expensive internal consistency |
| * checks. |
| */ |
| void |
| _PyObject_DebugMallocStats(void) |
| { |
| uint i; |
| const uint numclasses = SMALL_REQUEST_THRESHOLD >> ALIGNMENT_SHIFT; |
| /* # of pools, allocated blocks, and free blocks per class index */ |
| ulong numpools[SMALL_REQUEST_THRESHOLD >> ALIGNMENT_SHIFT]; |
| ulong numblocks[SMALL_REQUEST_THRESHOLD >> ALIGNMENT_SHIFT]; |
| ulong numfreeblocks[SMALL_REQUEST_THRESHOLD >> ALIGNMENT_SHIFT]; |
| /* total # of allocated bytes in used and full pools */ |
| ulong allocated_bytes = 0; |
| /* total # of available bytes in used pools */ |
| ulong available_bytes = 0; |
| /* # of free pools + pools not yet carved out of current arena */ |
| uint numfreepools = 0; |
| /* # of bytes for arena alignment padding */ |
| ulong arena_alignment = 0; |
| /* # of bytes in used and full pools used for pool_headers */ |
| ulong pool_header_bytes = 0; |
| /* # of bytes in used and full pools wasted due to quantization, |
| * i.e. the necessarily leftover space at the ends of used and |
| * full pools. |
| */ |
| ulong quantization = 0; |
| /* running total -- should equal narenas * ARENA_SIZE */ |
| ulong total; |
| char buf[128]; |
| |
| fprintf(stderr, "Small block threshold = %d, in %u size classes.\n", |
| SMALL_REQUEST_THRESHOLD, numclasses); |
| |
| for (i = 0; i < numclasses; ++i) |
| numpools[i] = numblocks[i] = numfreeblocks[i] = 0; |
| |
| /* Because full pools aren't linked to from anything, it's easiest |
| * 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 < narenas; ++i) { |
| uint poolsinarena; |
| uint j; |
| uptr base = arenas[i]; |
| |
| /* round up to pool alignment */ |
| poolsinarena = ARENA_SIZE / POOL_SIZE; |
| if (base & (uptr)POOL_SIZE_MASK) { |
| --poolsinarena; |
| arena_alignment += POOL_SIZE; |
| base &= ~(uptr)POOL_SIZE_MASK; |
| base += POOL_SIZE; |
| } |
| |
| if (i == narenas - 1) { |
| /* current arena may have raw memory at the end */ |
| numfreepools += nfreepools; |
| poolsinarena -= nfreepools; |
| } |
| |
| /* visit every pool in the arena */ |
| for (j = 0; j < poolsinarena; ++j, base += POOL_SIZE) { |
| poolp p = (poolp)base; |
| const uint sz = p->szidx; |
| uint freeblocks; |
| |
| if (p->ref.count == 0) { |
| /* currently unused */ |
| ++numfreepools; |
| assert(pool_is_in_list(p, freepools)); |
| continue; |
| } |
| ++numpools[sz]; |
| numblocks[sz] += p->ref.count; |
| freeblocks = NUMBLOCKS(sz) - p->ref.count; |
| numfreeblocks[sz] += freeblocks; |
| #ifdef Py_DEBUG |
| if (freeblocks > 0) |
| assert(pool_is_in_list(p, usedpools[sz + sz])); |
| #endif |
| } |
| } |
| |
| fputc('\n', stderr); |
| fputs("class size num pools blocks in use avail blocks\n" |
| "----- ---- --------- ------------- ------------\n", |
| stderr); |
| |
| for (i = 0; i < numclasses; ++i) { |
| ulong p = numpools[i]; |
| ulong b = numblocks[i]; |
| ulong f = numfreeblocks[i]; |
| uint size = INDEX2SIZE(i); |
| if (p == 0) { |
| assert(b == 0 && f == 0); |
| continue; |
| } |
| fprintf(stderr, "%5u %6u %11lu %15lu %13lu\n", |
| i, size, p, b, f); |
| allocated_bytes += b * size; |
| available_bytes += f * size; |
| pool_header_bytes += p * POOL_OVERHEAD; |
| quantization += p * ((POOL_SIZE - POOL_OVERHEAD) % size); |
| } |
| fputc('\n', stderr); |
| (void)printone("# times object malloc called", serialno); |
| |
| PyOS_snprintf(buf, sizeof(buf), |
| "%u arenas * %d bytes/arena", narenas, ARENA_SIZE); |
| (void)printone(buf, (ulong)narenas * ARENA_SIZE); |
| |
| fputc('\n', stderr); |
| |
| total = printone("# bytes in allocated blocks", allocated_bytes); |
| total += printone("# bytes in available blocks", available_bytes); |
| |
| PyOS_snprintf(buf, sizeof(buf), |
| "%u unused pools * %d bytes", numfreepools, POOL_SIZE); |
| total += printone(buf, (ulong)numfreepools * POOL_SIZE); |
| |
| total += printone("# bytes lost to pool headers", pool_header_bytes); |
| total += printone("# bytes lost to quantization", quantization); |
| total += printone("# bytes lost to arena alignment", arena_alignment); |
| (void)printone("Total", total); |
| } |
| |
| #endif /* PYMALLOC_DEBUG */ |