kiper220/mimalloc
1
0
Fork 0
mirror of https://github.com/microsoft/mimalloc.git synced 2025-05-08 00:09:31 +03:00
Code Issues Projects Releases Packages Wiki Activity Actions

add comments

Browse source
This commit is contained in:
daanx 2024-12-31 15:11:09 -08:00
parent 9665d604d3
commit 0d302cd174
1 changed files with 14 additions and 13 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

23
include/mimalloc/types.h
View file

@ -100,9 +100,10 @@ terms of the MIT license. A copy of the license can be found in the file
#endif
// ------------------------------------------------------
// --------------------------------------------------------------
// Sizes of internal data-structures
// ------------------------------------------------------
// (comments specify sizes on 64-bit, usually 32-bit is halved)
// --------------------------------------------------------------
// Sizes are for 64-bit
#ifndef MI_ARENA_SLICE_SHIFT
@ -116,8 +117,8 @@ terms of the MIT license. A copy of the license can be found in the file
#define MI_BCHUNK_BITS_SHIFT (6 + MI_SIZE_SHIFT) // optimized for 512 bits per chunk (avx512)
#endif
#define MI_BCHUNK_BITS (1 << MI_BCHUNK_BITS_SHIFT)
#define MI_ARENA_SLICE_SIZE (MI_ZU(1) << MI_ARENA_SLICE_SHIFT)
#define MI_BCHUNK_BITS (1 << MI_BCHUNK_BITS_SHIFT) // sub-bitmaps are "bchunks" of 512 bits
#define MI_ARENA_SLICE_SIZE (MI_ZU(1) << MI_ARENA_SLICE_SHIFT) // arena's allocate in slices of 64 KiB
#define MI_ARENA_SLICE_ALIGN (MI_ARENA_SLICE_SIZE)
#define MI_ARENA_MIN_OBJ_SLICES (1)
@ -126,9 +127,9 @@ terms of the MIT license. A copy of the license can be found in the file
#define MI_ARENA_MIN_OBJ_SIZE (MI_ARENA_MIN_OBJ_SLICES * MI_ARENA_SLICE_SIZE)
#define MI_ARENA_MAX_OBJ_SIZE (MI_ARENA_MAX_OBJ_SLICES * MI_ARENA_SLICE_SIZE)
#define MI_SMALL_PAGE_SIZE MI_ARENA_MIN_OBJ_SIZE
#define MI_MEDIUM_PAGE_SIZE (8*MI_SMALL_PAGE_SIZE) // 512 KiB (=byte in the bitmap)
#define MI_LARGE_PAGE_SIZE (MI_SIZE_SIZE*MI_MEDIUM_PAGE_SIZE) // 4 MiB (=word in the bitmap)
#define MI_SMALL_PAGE_SIZE MI_ARENA_MIN_OBJ_SIZE // 64 KiB
#define MI_MEDIUM_PAGE_SIZE (8*MI_SMALL_PAGE_SIZE) // 512 KiB (=byte in the bchunk bitmap)
#define MI_LARGE_PAGE_SIZE (MI_SIZE_SIZE*MI_MEDIUM_PAGE_SIZE) // 4 MiB (=word in the bchunk bitmap)
// Maximum number of size classes. (spaced exponentially in 12.5% increments)
#define MI_BIN_HUGE (73U)
@ -272,7 +273,7 @@ typedef uint8_t mi_heaptag_t;
//
// Notes:
// - Non-atomic fields can only be accessed if having ownership (low bit of `xthread_free`).
// - If a page is not part of a heap it is called "abandoned" -- in
// - If a page is not part of a heap it is called "abandoned" (`heap==NULL`) -- in
// that case the `xthreadid` is 0 or 1 (1 is for abandoned pages that
// are in the abandoned page lists of an arena, these are called "mapped" abandoned pages).
// - The layout is optimized for `free.c:mi_free` and `alloc.c:mi_page_alloc`
@ -304,7 +305,7 @@ typedef struct mi_page_s {
mi_heap_t* heap; // the heap owning this page (or NULL for abandoned pages)
struct mi_page_s* next; // next page owned by the heap with the same `block_size`
struct mi_page_s* prev; // previous page owned by the heap with the same `block_size`
size_t slice_committed; // committed size relative to the first arena slice of the page data
size_t slice_committed; // committed size relative to the first arena slice of the page data (or 0 if the page is fully committed already)
mi_memid_t memid; // provenance of the page memory
} mi_page_t;
@ -315,7 +316,7 @@ typedef struct mi_page_s {
#define MI_PAGE_ALIGN MI_ARENA_SLICE_ALIGN // pages must be aligned on this for the page map.
#define MI_PAGE_MIN_START_BLOCK_ALIGN MI_MAX_ALIGN_SIZE // minimal block alignment for the first block in a page (16b)
#define MI_PAGE_MAX_START_BLOCK_ALIGN2 MI_KiB // maximal block alignment for "power of 2"-sized blocks
#define MI_PAGE_MAX_START_BLOCK_ALIGN2 MI_KiB // maximal block alignment for "power of 2"-sized blocks (such that we guarantee natural alignment)
#define MI_PAGE_MAX_OVERALLOC_ALIGN MI_ARENA_SLICE_SIZE // (64 KiB) limit for which we overallocate in arena pages, beyond this use OS allocation
#if (MI_ENCODE_FREELIST || MI_PADDING) && MI_SIZE_SIZE == 8
@ -328,7 +329,7 @@ typedef struct mi_page_s {
// (Except for large pages since huge objects are allocated in 4MiB chunks)
#define MI_SMALL_MAX_OBJ_SIZE ((MI_SMALL_PAGE_SIZE-MI_PAGE_INFO_SIZE)/8) // < 8 KiB
#define MI_MEDIUM_MAX_OBJ_SIZE ((MI_MEDIUM_PAGE_SIZE-MI_PAGE_INFO_SIZE)/8) // < 64 KiB
#define MI_LARGE_MAX_OBJ_SIZE (MI_LARGE_PAGE_SIZE/4) // <= 512 KiB // note: this must be a nice power of 2 or we get rounding issues with _mi_bin
#define MI_LARGE_MAX_OBJ_SIZE (MI_LARGE_PAGE_SIZE/4) // <= 512 KiB // note: this must be a nice power of 2 or we get rounding issues with `_mi_bin`
#define MI_LARGE_MAX_OBJ_WSIZE (MI_LARGE_MAX_OBJ_SIZE/MI_SIZE_SIZE)