/* ---------------------------------------------------------------------------- Copyright (c) 2018, Microsoft Research, Daan Leijen This is free software; you can redistribute it and/or modify it under the terms of the MIT license. A copy of the license can be found in the file "LICENSE" at the root of this distribution. -----------------------------------------------------------------------------*/ #pragma once #ifndef __MIMALLOC_TYPES_H #define __MIMALLOC_TYPES_H #include // size_t etc. #include // ptrdiff_t #include // uintptr_t, uint16_t, etc // ------------------------------------------------------ // Variants // ------------------------------------------------------ // Define NDEBUG in the release version to disable assertions. // #define NDEBUG // Define MI_STAT as 1 to maintain statistics; set it to 2 to have detailed statistics (but costs some performance). // #define MI_STAT 1 // Define MI_SECURE as 1 to encode free lists // #define MI_SECURE 1 #if !defined(MI_SECURE) #define MI_SECURE 0 #endif // Define MI_DEBUG as 1 for basic assert checks and statistics // set it to 2 to do internal asserts, // and to 3 to do extensive invariant checking. #if !defined(MI_DEBUG) #if !defined(NDEBUG) || defined(_DEBUG) #define MI_DEBUG 1 #else #define MI_DEBUG 0 #endif #endif // ------------------------------------------------------ // Platform specific values // ------------------------------------------------------ // ------------------------------------------------------ // Size of a pointer. // We assume that `sizeof(void*)==sizeof(intptr_t)` // and it holds for all platforms we know of. // // However, the C standard only requires that: // p == (void*)((intptr_t)p)) // but we also need: // i == (intptr_t)((void*)i) // or otherwise one might define an intptr_t type that is larger than a pointer... // ------------------------------------------------------ #if INTPTR_MAX == 9223372036854775807LL # define MI_INTPTR_SHIFT (3) #elif INTPTR_MAX == 2147483647LL # define MI_INTPTR_SHIFT (2) #else #error platform must be 32 or 64 bits #endif #define MI_INTPTR_SIZE (1<>MI_INTPTR_SHIFT) // Maximum number of size classes. (spaced exponentially in 16.7% increments) #define MI_BIN_HUGE (64U) // Minimal alignment necessary. On most platforms 16 bytes are needed // due to SSE registers for example. This must be at least `MI_INTPTR_SIZE` #define MI_MAX_ALIGN_SIZE 16 // sizeof(max_align_t) #if (MI_LARGE_WSIZE_MAX > 131072) #error "define more bins" #endif typedef uintptr_t mi_encoded_t; // free lists contain blocks typedef struct mi_block_s { mi_encoded_t next; } mi_block_t; typedef enum mi_delayed_e { MI_NO_DELAYED_FREE = 0, MI_USE_DELAYED_FREE, MI_DELAYED_FREEING } mi_delayed_t; typedef union mi_page_flags_u { uint16_t value; struct { bool has_aligned; bool in_full; }; } mi_page_flags_t; // Thread free list. // We use 2 bits of the pointer for the `use_delayed_free` and `delayed_freeing` flags. typedef union mi_thread_free_u { uintptr_t value; struct { mi_delayed_t delayed:2; #if MI_INTPTR_SIZE==8 uintptr_t head:62; // head free block in the list (right-shifted by 2) #elif MI_INTPTR_SIZE==4 uintptr_t head:30; #endif }; } mi_thread_free_t; #define MI_TF_PTR_SHIFT (2) // A page contains blocks of one specific size (`block_size`). // Each page has three list of free blocks: // `free` for blocks that can be allocated, // `local_free` for freed blocks that are not yet available to `mi_malloc` // `thread_free` for freed blocks by other threads // The `local_free` and `thread_free` lists are migrated to the `free` list // when it is exhausted. The separate `local_free` list is necessary to // implement a monotonic heartbeat. The `thread_free` list is needed for // avoiding atomic operations in the common case. // // `used - thread_freed` == actual blocks that are in use (alive) // `used - thread_freed + |free| + |local_free| == capacity` // // note: we don't count `freed` (as |free|) instead of `used` to reduce // the number of memory accesses in the `mi_page_all_free` function(s). // note: the funny layout here is due to: // - access is optimized for `mi_free` and `mi_page_alloc` // - using `uint16_t` does not seem to slow things down typedef struct mi_page_s { // "owned" by the segment uint8_t segment_idx; // index in the segment `pages` array, `page == &segment->pages[page->segment_idx]` bool segment_in_use:1; // `true` if the segment allocated this page bool is_reset:1; // `true` if the page memory was reset // layout like this to optimize access in `mi_malloc` and `mi_free` mi_page_flags_t flags; uint16_t capacity; // number of blocks committed uint16_t reserved; // numbes of blocks reserved in memory mi_block_t* free; // list of available free blocks (`malloc` allocates from this list) uintptr_t cookie; // random cookie to encode the free lists size_t used; // number of blocks in use (including blocks in `local_free` and `thread_free`) mi_block_t* local_free; // list of deferred free blocks by this thread (migrates to `free`) volatile uintptr_t thread_freed; // at least this number of blocks are in `thread_free` volatile mi_thread_free_t thread_free; // list of deferred free blocks freed by other threads // less accessed info size_t block_size; // size available in each block (always `>0`) mi_heap_t* heap; // the owning heap struct mi_page_s* next; // next page owned by this thread with the same `block_size` struct mi_page_s* prev; // previous page owned by this thread with the same `block_size` // improve page index calculation #if MI_INTPTR_SIZE==8 //void* padding[1]; // 10 words on 64-bit #elif MI_INTPTR_SIZE==4 void* padding[1]; // 12 words on 32-bit #endif } mi_page_t; typedef enum mi_page_kind_e { MI_PAGE_SMALL, // small blocks go into 64kb pages inside a segment MI_PAGE_LARGE, // larger blocks go into a single page spanning a whole segment MI_PAGE_HUGE // huge blocks (>512kb) are put into a single page in a segment of the exact size (but still 2mb aligned) } mi_page_kind_t; // Segments are large allocated memory blocks (2mb on 64 bit) from // the OS. Inside segments we allocated fixed size _pages_ that // contain blocks. typedef struct mi_segment_s { struct mi_segment_s* next; struct mi_segment_s* prev; struct mi_segment_s* abandoned_next; size_t abandoned; // abandoned pages (i.e. the original owning thread stopped) (`abandoned <= used`) size_t used; // count of pages in use (`used <= capacity`) size_t capacity; // count of available pages (`#free + used`) size_t segment_size;// for huge pages this may be different from `MI_SEGMENT_SIZE` size_t segment_info_size; // space we are using from the first page for segment meta-data and possible guard pages. uintptr_t cookie; // verify addresses in debug mode: `mi_ptr_cookie(segment) == segment->cookie` // layout like this to optimize access in `mi_free` size_t page_shift; // `1 << page_shift` == the page sizes == `page->block_size * page->reserved` (unless the first page, then `-segment_info_size`). uintptr_t thread_id; // unique id of the thread owning this segment mi_page_kind_t page_kind; // kind of pages: small, large, or huge mi_page_t pages[1]; // up to `MI_SMALL_PAGES_PER_SEGMENT` pages } mi_segment_t; // ------------------------------------------------------ // Heaps // Provide first-class heaps to allocate from. // A heap just owns a set of pages for allocation and // can only be allocate/reallocate from the thread that created it. // Freeing blocks can be done from any thread though. // Per thread, the segments are shared among its heaps. // Per thread, there is always a default heap that is // used for allocation; it is initialized to statically // point to an empty heap to avoid initialization checks // in the fast path. // ------------------------------------------------------ // Thread local data typedef struct mi_tld_s mi_tld_t; // Pages of a certain block size are held in a queue. typedef struct mi_page_queue_s { mi_page_t* first; mi_page_t* last; size_t block_size; } mi_page_queue_t; #define MI_BIN_FULL (MI_BIN_HUGE+1) // A heap owns a set of pages. struct mi_heap_s { mi_tld_t* tld; mi_page_t* pages_free_direct[MI_SMALL_WSIZE_MAX + 2]; // optimize: array where every entry points a page with possibly free blocks in the corresponding queue for that size. mi_page_queue_t pages[MI_BIN_FULL + 1]; // queue of pages for each size class (or "bin") volatile mi_block_t* thread_delayed_free; uintptr_t thread_id; // thread this heap belongs too uintptr_t cookie; uintptr_t random; // random number used for secure allocation size_t page_count; // total number of pages in the `pages` queues. bool no_reclaim; // `true` if this heap should not reclaim abandoned pages }; // ------------------------------------------------------ // Debug // ------------------------------------------------------ #define MI_DEBUG_UNINIT (0xD0) #define MI_DEBUG_FREED (0xDF) #if (MI_DEBUG) // use our own assertion to print without memory allocation void _mi_assert_fail(const char* assertion, const char* fname, unsigned int line, const char* func ); #define mi_assert(expr) ((expr) ? (void)0 : _mi_assert_fail(#expr,__FILE__,__LINE__,__func__)) #else #define mi_assert(x) #endif #if (MI_DEBUG>1) #define mi_assert_internal mi_assert #else #define mi_assert_internal(x) #endif #if (MI_DEBUG>2) #define mi_assert_expensive mi_assert #else #define mi_assert_expensive(x) #endif // ------------------------------------------------------ // Statistics // ------------------------------------------------------ #ifndef MI_STAT #if (MI_DEBUG>0) #define MI_STAT 2 #else #define MI_STAT 0 #endif #endif typedef struct mi_stat_count_s { int64_t allocated; int64_t freed; int64_t peak; int64_t current; } mi_stat_count_t; typedef struct mi_stat_counter_s { int64_t total; int64_t count; } mi_stat_counter_t; typedef struct mi_stats_s { mi_stat_count_t segments; mi_stat_count_t pages; mi_stat_count_t reserved; mi_stat_count_t committed; mi_stat_count_t reset; mi_stat_count_t segments_abandoned; mi_stat_count_t pages_abandoned; mi_stat_count_t pages_extended; mi_stat_count_t mmap_calls; mi_stat_count_t mmap_right_align; mi_stat_count_t mmap_ensure_aligned; mi_stat_count_t threads; mi_stat_count_t huge; mi_stat_count_t malloc; mi_stat_counter_t searches; #if MI_STAT>1 mi_stat_count_t normal[MI_BIN_HUGE+1]; #endif } mi_stats_t; void _mi_stat_increase(mi_stat_count_t* stat, size_t amount); void _mi_stat_decrease(mi_stat_count_t* stat, size_t amount); void _mi_stat_counter_increase(mi_stat_counter_t* stat, size_t amount); #if (MI_STAT) #define mi_stat_increase(stat,amount) _mi_stat_increase( &(stat), amount) #define mi_stat_decrease(stat,amount) _mi_stat_decrease( &(stat), amount) #define mi_stat_counter_increase(stat,amount) _mi_stat_counter_increase( &(stat), amount) #else #define mi_stat_increase(stat,amount) (void)0 #define mi_stat_decrease(stat,amount) (void)0 #define mi_stat_counter_increase(stat,amount) (void)0 #endif #define mi_heap_stat_increase(heap,stat,amount) mi_stat_increase( (heap)->tld->stats.stat, amount) #define mi_heap_stat_decrease(heap,stat,amount) mi_stat_decrease( (heap)->tld->stats.stat, amount) // ------------------------------------------------------ // Thread Local data // ------------------------------------------------------ // Queue of segments typedef struct mi_segment_queue_s { mi_segment_t* first; mi_segment_t* last; } mi_segment_queue_t; // Segments thread local data typedef struct mi_segments_tld_s { mi_segment_queue_t small_free; // queue of segments with free small pages size_t current_size; // current size of all segments size_t peak_size; // peak size of all segments size_t cache_count; // number of segments in the cache size_t cache_size; // total size of all segments in the cache mi_segment_queue_t cache; // (small) cache of segments for small and large pages (to avoid repeated mmap calls) mi_stats_t* stats; // points to tld stats } mi_segments_tld_t; // OS thread local data typedef struct mi_os_tld_s { uintptr_t mmap_next_probable; // probable next address start allocated by mmap (to guess which path to take on alignment) void* mmap_previous; // previous address returned by mmap uint8_t* pool; // pool of segments to reduce mmap calls on some platforms size_t pool_available; // bytes available in the pool mi_stats_t* stats; // points to tld stats } mi_os_tld_t; // Thread local data struct mi_tld_s { unsigned long long heartbeat; // monotonic heartbeat count mi_heap_t* heap_backing; // backing heap of this thread (cannot be deleted) mi_segments_tld_t segments; // segment tld mi_os_tld_t os; // os tld mi_stats_t stats; // statistics }; #endif