notaz.gp2x.de / pcsx_rearmed.git / blame
| Commit | Line | Data |
|---|---|---|
| 02487de7 PC |
1 | # tlsf |
| 2 | Two-Level Segregated Fit memory allocator implementation. | |
| 3 | Written by Matthew Conte (matt@baisoku.org). | |
| 4 | Released under the BSD license. | |
| 5 | ||
| 6 | Features | |
| 7 | -------- | |
| 8 | * O(1) cost for malloc, free, realloc, memalign | |
| 9 | * Extremely low overhead per allocation (4 bytes) | |
| 10 | * Low overhead per TLSF management of pools (~3kB) | |
| 11 | * Low fragmentation | |
| 12 | * Compiles to only a few kB of code and data | |
| 13 | * Support for adding and removing memory pool regions on the fly | |
| 14 | ||
| 15 | Caveats | |
| 16 | ------- | |
| 17 | * Currently, assumes architecture can make 4-byte aligned accesses | |
| 18 | * Not designed to be thread safe; the user must provide this | |
| 19 | ||
| 20 | Notes | |
| 21 | ----- | |
| 22 | This code was based on the TLSF 1.4 spec and documentation found at: | |
| 23 | ||
| 24 | http://www.gii.upv.es/tlsf/main/docs | |
| 25 | ||
| 26 | It also leverages the TLSF 2.0 improvement to shrink the per-block overhead from 8 to 4 bytes. | |
| 27 | ||
| 28 | History | |
| 29 | ------- | |
| 30 | 2016/04/10 - v3.1 | |
| 31 | * Code moved to github | |
| 32 | * tlsfbits.h rolled into tlsf.c | |
| 33 | * License changed to BSD | |
| 34 | ||
| 35 | 2014/02/08 - v3.0 | |
| 36 | * This version is based on improvements from 3DInteractive GmbH | |
| 37 | * Interface changed to allow more than one memory pool | |
| 38 | * Separated pool handling from control structure (adding, removing, debugging) | |
| 39 | * Control structure and pools can still be constructed in the same memory block | |
| 40 | * Memory blocks for control structure and pools are checked for alignment | |
| 41 | * Added functions to retrieve control structure size, alignment size, min and max block size, overhead of pool structure, and overhead of a single allocation | |
| 42 | * Minimal Pool size is tlsf_block_size_min() + tlsf_pool_overhead() | |
| 43 | * Pool must be empty when it is removed, in order to allow O(1) removal | |
| 44 | ||
| 45 | 2011/10/20 - v2.0 | |
| 46 | * 64-bit support | |
| 47 | * More compiler intrinsics for ffs/fls | |
| 48 | * ffs/fls verification during TLSF creation in debug builds | |
| 49 | ||
| 50 | 2008/04/04 - v1.9 | |
| 51 | * Add tlsf_heap_check, a heap integrity check | |
| 52 | * Support a predefined tlsf_assert macro | |
| 53 | * Fix realloc case where block should shrink; if adjacent block is in use, execution would go down the slow path | |
| 54 | ||
| 55 | 2007/02/08 - v1.8 | |
| 56 | * Fix for unnecessary reallocation in tlsf_realloc | |
| 57 | ||
| 58 | 2007/02/03 - v1.7 | |
| 59 | * tlsf_heap_walk takes a callback | |
| 60 | * tlsf_realloc now returns NULL on failure | |
| 61 | * tlsf_memalign optimization for 4-byte alignment | |
| 62 | * Usage of size_t where appropriate | |
| 63 | ||
| 64 | 2006/11/21 - v1.6 | |
| 65 | * ffs/fls broken out into tlsfbits.h | |
| 66 | * tlsf_overhead queries per-pool overhead | |
| 67 | ||
| 68 | 2006/11/07 - v1.5 | |
| 69 | * Smart realloc implementation | |
| 70 | * Smart memalign implementation | |
| 71 | ||
| 72 | 2006/10/11 - v1.4 | |
| 73 | * Add some ffs/fls implementations | |
| 74 | * Minor code footprint reduction | |
| 75 | ||
| 76 | 2006/09/14 - v1.3 | |
| 77 | * Profiling indicates heavy use of blocks of size 1-128, so implement small block handling | |
| 78 | * Reduce pool overhead by about 1kb | |
| 79 | * Reduce minimum block size from 32 to 12 bytes | |
| 80 | * Realloc bug fix | |
| 81 | ||
| 82 | 2006/09/09 - v1.2 | |
| 83 | * Add tlsf_block_size | |
| 84 | * Static assertion mechanism for invariants | |
| 85 | * Minor bugfixes | |
| 86 | ||
| 87 | 2006/09/01 - v1.1 | |
| 88 | * Add tlsf_realloc | |
| 89 | * Add tlsf_walk_heap | |
| 90 | ||
| 91 | 2006/08/25 - v1.0 | |
| 92 | * First release |