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merge from dev with new page fields (block_size and is_huge)

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Daan Leijen
2024-03-24 22:12:33 -07:00
parent e363f477a7 006ae2d055
commit 3c85983a35
16 changed files with 220 additions and 227 deletions
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46
include/mimalloc/types.h
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@@ -1,5 +1,5 @@
/* ----------------------------------------------------------------------------
Copyright (c) 2018-2023, Microsoft Research, Daan Leijen
Copyright (c) 2018-2024, 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.
@@ -193,16 +193,13 @@ typedef int32_t mi_ssize_t;
#endif
// Maximum slice offset (15)
#define MI_MAX_SLICE_OFFSET ((MI_ALIGNMENT_MAX / MI_SEGMENT_SLICE_SIZE) - 1)
// Used as a special value to encode block sizes in 32 bits.
#define MI_HUGE_BLOCK_SIZE ((uint32_t)(2*MI_GiB))
#define MI_MAX_SLICE_OFFSET ((MI_BLOCK_ALIGNMENT_MAX / MI_SEGMENT_SLICE_SIZE) - 1)
// blocks up to this size are always allocated aligned
#define MI_MAX_ALIGN_GUARANTEE (8*MI_MAX_ALIGN_SIZE)
// Alignments over MI_ALIGNMENT_MAX are allocated in dedicated huge page segments
#define MI_ALIGNMENT_MAX (MI_SEGMENT_SIZE >> 1)
// Alignments over MI_BLOCK_ALIGNMENT_MAX are allocated in dedicated huge page segments
#define MI_BLOCK_ALIGNMENT_MAX (MI_SEGMENT_SIZE >> 1)
// ------------------------------------------------------
@@ -266,7 +263,6 @@ typedef uintptr_t mi_thread_free_t;
// implement a monotonic heartbeat. The `thread_free` list is needed for
// avoiding atomic operations in the common case.
//
//
// `used - |thread_free|` == actual blocks that are in use (alive)
// `used - |thread_free| + |free| + |local_free| == capacity`
//
@@ -274,16 +270,13 @@ typedef uintptr_t mi_thread_free_t;
// the number of memory accesses in the `mi_page_all_free` function(s).
//
// Notes:
// - Access is optimized for `mi_free` and `mi_page_alloc` (in `alloc.c`)
// - Access is optimized for `free.c:mi_free` and `alloc.c:mi_page_alloc`
// - Using `uint16_t` does not seem to slow things down
// - The size is 8 words on 64-bit which helps the page index calculations
// (and 10 words on 32-bit, and encoded free lists add 2 words. Sizes 10
// and 12 are still good for address calculation)
// - To limit the structure size, the `xblock_size` is 32-bits only; for
// blocks > MI_HUGE_BLOCK_SIZE the size is determined from the segment page size
// - The size is 12 words on 64-bit which helps the page index calculations
// (and 14 words on 32-bit, and encoded free lists add 2 words)
// - `xthread_free` uses the bottom bits as a delayed-free flags to optimize
// concurrent frees where only the first concurrent free adds to the owning
// heap `thread_delayed_free` list (see `alloc.c:mi_free_block_mt`).
// heap `thread_delayed_free` list (see `free.c:mi_free_block_mt`).
// The invariant is that no-delayed-free is only set if there is
// at least one block that will be added, or as already been added, to
// the owning heap `thread_delayed_free` list. This guarantees that pages
@@ -294,20 +287,21 @@ typedef struct mi_page_s {
uint32_t slice_offset; // distance from the actual page data slice (0 if a page)
uint8_t is_committed : 1; // `true` if the page virtual memory is committed
uint8_t is_zero_init : 1; // `true` if the page was initially zero initialized
uint8_t is_huge:1; // `true` if the page is in a huge segment
// padding
// layout like this to optimize access in `mi_malloc` and `mi_free`
uint16_t capacity; // number of blocks committed, must be the first field, see `segment.c:page_clear`
uint16_t reserved; // number of blocks reserved in memory
uint16_t used; // number of blocks in use (including blocks in `thread_free`)
mi_page_flags_t flags; // `in_full` and `has_aligned` flags (8 bits)
uint8_t free_is_zero : 1; // `true` if the blocks in the free list are zero initialized
uint8_t retire_expire : 7; // expiration count for retired blocks
uint8_t block_size_shift; // if not zero, then `(1 << block_size_shift) == block_size` (only used for fast path in `free.c:_mi_page_ptr_unalign`)
uint8_t free_is_zero:1; // `true` if the blocks in the free list are zero initialized
uint8_t retire_expire:7; // expiration count for retired blocks
// padding
mi_block_t* free; // list of available free blocks (`malloc` allocates from this list)
mi_block_t* local_free; // list of deferred free blocks by this thread (migrates to `free`)
uint16_t used; // number of blocks in use (including blocks in `thread_free`)
uint8_t block_size_shift; // if not zero, then `(1 << block_size_shift) == block_size` (only used for fast path in `free.c:_mi_page_ptr_unalign`)
uint8_t block_offset_adj; // if not zero, then `(mi_page_start(_,page,_) - (uint8_t*)page - MI_MAX_ALIGN_SIZE*(block_offset_adj-1)) % block_size == 0)` (only used for fast path in `free.c:_mi_page_ptr_unalign`)
uint32_t xblock_size; // size available in each block (always `>0`)
size_t block_size; // size available in each block (always `>0`)
uint8_t* page_start; // start of the page area containing the blocks
#if (MI_ENCODE_FREELIST || MI_PADDING)
uintptr_t keys[2]; // two random keys to encode the free lists (see `_mi_block_next`) or padding canary
@@ -319,10 +313,8 @@ typedef struct mi_page_s {
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`
// 64-bit 9 words, 32-bit 12 words, (+2 for secure)
#if MI_INTPTR_SIZE==8
uintptr_t padding[1];
#endif
// 64-bit 11 words, 32-bit 13 words, (+2 for secure)
void* padding[1];
} mi_page_t;