Mercurial > hg > xemacs-beta
annotate src/mc-alloc.c @ 5238:2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
| author | Marcus Crestani <crestani@informatik.uni-tuebingen.de> |
|---|---|
| date | Mon, 05 Jul 2010 18:17:39 +0200 |
| parents | 9b8c2168d231 |
| children | b249c479f9e1 308d34e9f07d |
| rev | line source |
|---|---|
| 2720 | 1 /* New size-based allocator for XEmacs. |
| 2 Copyright (C) 2005 Marcus Crestani. | |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
3 Copyright (C) 2010 Ben Wing. |
| 2720 | 4 |
| 5 This file is part of XEmacs. | |
| 6 | |
| 7 XEmacs is free software; you can redistribute it and/or modify it | |
| 8 under the terms of the GNU General Public License as published by the | |
| 9 Free Software Foundation; either version 2, or (at your option) any | |
| 10 later version. | |
| 11 | |
| 12 XEmacs is distributed in the hope that it will be useful, but WITHOUT | |
| 13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 15 for more details. | |
| 16 | |
| 17 You should have received a copy of the GNU General Public License | |
| 18 along with XEmacs; see the file COPYING. If not, write to | |
| 19 the Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
| 20 Boston, MA 02111-1307, USA. */ | |
| 21 | |
| 22 /* Synched up with: Not in FSF. */ | |
| 23 | |
|
5238
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
24 /* |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
25 The New Allocator |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
26 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
27 The ideas and algorithms are based on the allocator of the |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
28 Boehm-Demers-Weiser conservative garbage collector. See |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
29 http://www.hpl.hp.com/personal/Hans_ Boehm/gc/index.html. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
30 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
31 The new allocator is enabled when the new garbage collector |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
32 is enabled (with `--with-newgc'). The implementation of |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
33 the new garbage collector is in gc.c. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
34 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
35 The new allocator takes care of: |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
36 - allocating objects in a write-barrier-friendly way |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
37 - manage object's mark bits |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
38 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
39 Three-Level Allocation |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
40 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
41 The new allocator efficiently manages the allocation of Lisp |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
42 objects by minimizing the number of times malloc() and free() are |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
43 called. The allocation process has three layers of abstraction: |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
44 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
45 1. It allocates memory in very large chunks called heap sections. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
46 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
47 2. The heap sections are subdivided into pages. The page size is |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
48 determined by the constant PAGE_SIZE. It holds the size of a page |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
49 in bytes. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
50 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
51 3. One page consists of one or more cells. Each cell represents |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
52 a memory location for an object. The cells on one page all have |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
53 the same size, thus every page only contains equal-sized |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
54 objects. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
55 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
56 If an object is bigger than page size, it is allocated on a |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
57 multi-page. Then there is only one cell on a multi-page (the cell |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
58 covers the full multi-page). Is an object smaller than 1/2 PAGE_SIZE, |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
59 a page contains several objects and several cells. There |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
60 is only one cell on a page for object sizes from 1/2 PAGE_SIZE to |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
61 PAGE_SIZE (whereas multi-pages always contain 2 only one |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
62 cell). Only in layer one malloc() and free() are called. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
63 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
64 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
65 Size Classes and Page Lists |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
66 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
67 Meta-information about every page and multi-page is kept in a page |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
68 header. The page header contains some bookkeeping information like |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
69 number of used and free cells, and pointers to other page |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
70 headers. The page headers are linked in a page list. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
71 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
72 Every page list builds a size class. A size class contains all |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
73 pages (linked via page headers) for objects of the same size. The |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
74 new allocator does not group objects based on their type, it groups |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
75 objects based on their sizes. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
76 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
77 Here is an example: A cons contains a lrecord_header, a car and cdr |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
78 field. Altogether it uses 12 bytes of memory (on 32 bits |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
79 machines). All conses are allocated on pages with a cell size of 12 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
80 bytes. All theses pages are kept together in a page list, which |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
81 represents the size class for 12 bytes objects. But this size class |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
82 is not exclusively for conses only. Other objects, which are also |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
83 12 bytes big (e.g. weak-boxes), are allocated in the same size |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
84 class and on the same pages. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
85 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
86 The number of size classes is customizable, so is the size step |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
87 between successive size classes. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
88 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
89 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
90 Used and Unused Heap |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
91 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
92 The memory which is managed by the allocator can be divided in two |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
93 logical parts: |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
94 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
95 The used heap contains pages, on which objects are allocated. These |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
96 pages are com- pletely or partially occupied. In the used heap, it |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
97 is important to quickly find a free spot for a new |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
98 object. Therefore the size classes of the used heap are defined by |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
99 the size of the cells on the pages. The size classes should match |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
100 common object sizes, to avoid wasting memory. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
101 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
102 The unused heap only contains completely empty pages. They have |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
103 never been used or have been freed completely again. In the unused |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
104 heap, the size of consecutive memory tips the scales. A page is the |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
105 smallest entity which is asked for. Therefore, the size classes of |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
106 the unused heap are defined by the number of consecutive pages. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
107 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
108 The parameters for the different size classes can be adjusted |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
109 independently, see `configurable values' below. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
110 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
111 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
112 The Allocator's Data Structures |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
113 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
114 The struct `mc_allocator_globals holds' all the data structures |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
115 that the new allocator uses (lists of used and unused pages, mark |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
116 bits, etc.). |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
117 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
118 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
119 Mapping of Heap Pointers to Page Headers |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
120 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
121 For caching benefits, the page headers and mark bits are stored |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
122 separately from their associated page. During garbage collection |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
123 (i.e. for marking and freeing objects) it is important to identify |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
124 the page header which is responsible for a given Lisp object. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
125 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
126 To do this task quickly, I added a two level search tree: the upper |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
127 10 bits of the heap pointer are the index of the first level. This |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
128 entry of the first level links to the second level, where the next |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
129 10 bits of the heap pointer are used to identify the page |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
130 header. The remaining bits point to the object relative to the |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
131 page. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
132 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
133 On architectures with more than 32 bits pointers, a hash value of |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
134 the upper bits is used to index into the first level. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
135 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
136 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
137 Mark Bits |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
138 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
139 For caching purposes, the mark bits are no longer kept within the |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
140 objects, they are kept in a separate bit field. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
141 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
142 Every page header has a field for the mark bits of the objects on |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
143 the page. If there are less cells on the page than there fit bits |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
144 in the integral data type EMACS_INT, the mark bits are stored |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
145 directly in this EMACS_INT. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
146 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
147 Otherwise, the mark bits are written in a separate space, with the |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
148 page header pointing to this space. This happens to pages with |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
149 rather small objects: many cells fit on a page, thus many mark bits |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
150 are needed. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
151 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
152 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
153 Allocate Memory |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
154 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
155 Use |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
156 void *mc_alloc (size_t size) |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
157 to request memory from the allocator. This returns a pointer to a |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
158 newly allocated block of memory of given size. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
159 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
160 This is how the new allocator allocates memory: |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
161 1. Determine the size class of the object. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
162 2. Is there already a page in this size class and is there a free |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
163 cell on this page? |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
164 * YES |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
165 3. Unlink free cell from free list, return address of free cell. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
166 DONE. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
167 * NO |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
168 3. Is there a page in the unused heap? |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
169 * YES |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
170 4. Move unused page to used heap. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
171 5. Initialize page header, free list, and mark bits. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
172 6. Unlink first cell from free list, return address of cell. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
173 DONE. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
174 * NO |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
175 4. Expand the heap, add new memory to unused heap |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
176 [go back to 3. and proceed with the YES case]. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
177 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
178 The allocator puts partially filled pages to the front of the page |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
179 list, completely filled ones to the end. That guarantees a fast |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
180 terminating search for free cells. Are there two successive full |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
181 pages at the front of the page list, the complete size class is |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
182 full, a new page has to be added. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
183 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
184 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
185 Expand Heap |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
186 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
187 To expand the heap, a big chunk of contiguous memory is allocated |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
188 using malloc(). These pieces are called heap sections. How big a new |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
189 heap section is (and thus the growth of the heap) is adjustable: See |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
190 MIN_HEAP_INCREASE, MAX_HEAP_INCREASE, and HEAP_GROWTH_DIVISOR below. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
191 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
192 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
193 Free Memory |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
194 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
195 One optimization in XEmacs is that locally used Lisp objects are |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
196 freed manually (the memory is not wasted till the next garbage |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
197 collection). Therefore the new allocator provides this function: |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
198 void mc_free (void *ptr) |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
199 That frees the object pointed to by ptr. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
200 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
201 This function is also used internally during sweep phase of the |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
202 garbage collection. This is how it works in detail: |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
203 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
204 1. Use pointer to identify page header |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
205 (use lookup mechanism described above). |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
206 2. Mark cell as free and hook it into free list. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
207 3. Is the page completely empty? |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
208 * YES |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
209 4. Unlink page from page list. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
210 5. Remove page header, free list, and mark bits. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
211 6. Move page to unused heap. |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
212 * NO |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
213 4. Move page to front of size class (to speed up allocation |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
214 of objects). |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
215 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
216 If the last object of a page is freed, the empty page is returned to |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
217 the unused heap. The allocator tries to coalesce adjacent pages, to |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
218 gain a big piece of contiguous memory. The resulting chunk is hooked |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
219 into the according size class of the unused heap. If this created a |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
220 complete heap section, the heap section is returned to the operating |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
221 system by using free(). |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
222 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
223 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
224 Allocator and Garbage Collector |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
225 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
226 The new allocator simplifies the interface to the Garbage Collector: |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
227 * mark live objects: MARK_[WHITE|GREY|BLACK] (ptr) |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
228 * sweep heap: EMACS_INT mc_sweep (void) |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
229 * run finalizers: EMACS_INT mc_finalize (void) |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
230 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
231 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
232 Allocator and Dumper |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
233 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
234 The new allocator provides special finalization for the portable |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
235 dumper (to save disk space): EMACS_INT mc_finalize_for_disksave (void) |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
236 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
237 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
238 More Information |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
239 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
240 More details can be found in |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
241 http://crestani.de/xemacs/pdf/mc-alloc.pdf . |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
242 |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
243 */ |
|
2cc24c69446c
Document the new allocator and the new garbage collector in gc.c and mc-alloc.c.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5216
diff
changeset
|
244 |
| 2720 | 245 #include <config.h> |
| 3092 | 246 |
| 2720 | 247 #include "lisp.h" |
| 248 #include "mc-alloc.h" | |
| 3092 | 249 #include "getpagesize.h" |
| 250 | |
| 251 | |
| 252 #if 0 | |
| 253 # define USE_MARK_BITS_FREE_LIST 1 | |
| 254 #endif | |
| 255 #if 1 | |
| 256 # define BLOCKTYPE_ALLOC_PAGE_HEADER 1 | |
| 257 #endif | |
| 258 | |
| 259 /* Memory protection needs the real system-dependent pagesize. */ | |
| 260 #ifndef WIN32_NATIVE | |
| 261 #include <unistd.h> /* for getpagesize () */ | |
| 262 #endif | |
| 263 #if defined (HAVE_GETPAGESIZE) | |
| 264 # define SYS_PAGE_SIZE getpagesize () | |
| 265 #elif defined (_SC_PAGESIZE) | |
| 266 # define SYS_PAGE_SIZE sysconf (_SC_PAGESIZE) | |
| 267 #elif defined (_SC_PAGE_SIZE) | |
| 268 # define SYS_PAGE_SIZE sysconf (_SC_PAGE_SIZE) | |
| 269 #elif defined(get_page_size) | |
| 270 # define SYS_PAGE_SIZE get_page_size () | |
| 271 #elif defined(PAGESIZE) | |
| 272 # define SYS_PAGE_SIZE PAGESIZE | |
| 273 #elif defined(PAGE_SIZE) | |
| 274 # define SYS_PAGE_SIZE PAGE_SIZE | |
| 275 #else | |
| 276 /* Valid page sizes are powers of 2. */ | |
| 277 # define SYS_PAGE_SIZE 4096 | |
| 278 #endif | |
| 2720 | 279 |
| 280 | |
| 281 /*--- configurable values ----------------------------------------------*/ | |
| 282 | |
| 283 /* Definition of size classes */ | |
| 284 | |
| 285 /* Heap used list constants: In the used heap, it is important to | |
| 286 quickly find a free spot for a new object. Therefore the size | |
| 287 classes of the used heap are defined by the size of the cells on | |
| 288 the pages. The size classes should match common object sizes, to | |
| 289 avoid wasting memory. */ | |
| 290 | |
| 291 /* Minimum object size in bytes. */ | |
| 3092 | 292 #if BITS_PER_EMACS_INT > 32 |
| 293 # define USED_LIST_MIN_OBJECT_SIZE 16 | |
| 294 #else | |
| 295 # define USED_LIST_MIN_OBJECT_SIZE 8 | |
| 296 #endif | |
| 2720 | 297 |
| 298 /* The step size by which the size classes increase (up to upper | |
| 299 threshold). This many bytes are mapped to a single used list: */ | |
| 3092 | 300 #if BITS_PER_EMACS_INT > 32 |
| 301 # define USED_LIST_LIN_STEP 8 | |
| 302 #else | |
| 303 # define USED_LIST_LIN_STEP 4 | |
| 304 #endif | |
| 2720 | 305 |
| 306 /* The upper threshold should always be set to PAGE_SIZE/2, because if | |
| 307 a object is larger than PAGE_SIZE/2 there is no room for any other | |
| 308 object on this page. Objects this big are kept in the page list of | |
| 309 the multiple pages, since a quick search for free spots is not | |
| 310 needed for this kind of pages (because there are no free spots). | |
| 311 PAGE_SIZES_DIV_2 defines maximum size of a used space list. */ | |
| 3092 | 312 #define USED_LIST_UPPER_THRESHOLD PAGE_SIZE_DIV_2 |
| 2720 | 313 |
| 314 | |
| 315 /* Heap free list constants: In the unused heap, the size of | |
| 316 consecutive memory tips the scales. A page is smallest entity which | |
| 317 is asked for. Therefore, the size classes of the unused heap are | |
| 318 defined by the number of consecutive pages. */ | |
| 319 /* Sizes up to this many pages each have their own free list. */ | |
| 320 #define FREE_LIST_LOWER_THRESHOLD 32 | |
| 321 /* The step size by which the size classes increase (up to upper | |
| 322 threshold). FREE_LIST_LIN_STEP number of sizes are mapped to a | |
| 323 single free list for sizes between FREE_LIST_LOWER_THRESHOLD and | |
| 324 FREE_LIST_UPPER_THRESHOLD. */ | |
| 325 #define FREE_LIST_LIN_STEP 8 | |
| 326 /* Sizes of at least this many pages are mapped to a single free | |
| 327 list. Blocks of memory larger than this number are all kept in a | |
| 328 single list, which makes searching this list slow. But objects that | |
| 329 big are really seldom. */ | |
| 330 #define FREE_LIST_UPPER_THRESHOLD 256 | |
| 331 | |
| 332 | |
| 3092 | 333 /* used heap list count */ |
| 334 #define N_USED_PAGE_LISTS (((USED_LIST_UPPER_THRESHOLD \ | |
| 335 - USED_LIST_MIN_OBJECT_SIZE) \ | |
| 336 / USED_LIST_LIN_STEP) + 1 ) + 1 | |
| 337 | |
| 338 /* free heap list count */ | |
| 339 #define N_FREE_PAGE_LISTS (((FREE_LIST_UPPER_THRESHOLD \ | |
| 340 - FREE_LIST_LOWER_THRESHOLD) \ | |
| 341 / FREE_LIST_LIN_STEP) \ | |
| 342 + FREE_LIST_LOWER_THRESHOLD) | |
| 343 | |
| 344 | |
| 2720 | 345 /* Maximum number of separately added heap sections. */ |
| 346 #if BITS_PER_EMACS_INT > 32 | |
| 347 # define MAX_HEAP_SECTS 2048 | |
| 348 #else | |
| 349 # define MAX_HEAP_SECTS 768 | |
| 350 #endif | |
| 351 | |
| 352 | |
| 353 /* Heap growth constants. Heap increases by any number between the | |
| 354 boundaries (unit is PAGE_SIZE). */ | |
| 3092 | 355 #define MIN_HEAP_INCREASE 256 |
| 2720 | 356 #define MAX_HEAP_INCREASE 256 /* not used */ |
| 357 | |
| 358 /* Every heap growth is calculated like this: | |
| 359 needed_pages + ( HEAP_SIZE / ( PAGE_SIZE * HEAP_GROWTH_DIVISOR )). | |
| 360 So the growth of the heap is influenced by the current size of the | |
| 361 heap, but kept between MIN_HEAP_INCREASE and MAX_HEAP_INCREASE | |
| 362 boundaries. | |
| 363 This reduces the number of heap sectors, the larger the heap grows | |
| 364 the larger are the newly allocated chunks. */ | |
| 365 #define HEAP_GROWTH_DIVISOR 3 | |
| 366 | |
| 367 | |
| 368 /* Zero memory before putting on free lists. */ | |
| 369 #define ZERO_MEM 1 | |
| 370 | |
| 371 | |
| 372 #ifndef CHAR_BIT /* should be included by limits.h */ | |
| 373 # define CHAR_BIT BITS_PER_CHAR | |
| 374 #endif | |
| 375 | |
| 376 | |
| 3092 | 377 |
| 378 /*--- values depending on PAGE_SIZE ------------------------------------*/ | |
| 2720 | 379 |
| 3092 | 380 /* initialized in init_mc_allocator () */ |
| 381 static EMACS_INT log_page_size; | |
| 382 static EMACS_INT page_size_div_2; | |
| 2720 | 383 |
| 3092 | 384 #undef PAGE_SIZE |
| 385 #define PAGE_SIZE SYS_PAGE_SIZE | |
| 386 #define LOG_PAGE_SIZE log_page_size | |
| 387 #define PAGE_SIZE_DIV_2 page_size_div_2 | |
| 2720 | 388 |
| 389 | |
| 390 /* Constants for heap address to page header mapping. */ | |
| 391 #define LOG_LEVEL2_SIZE 10 | |
| 392 #define LEVEL2_SIZE (1 << LOG_LEVEL2_SIZE) | |
| 393 #if BITS_PER_EMACS_INT > 32 | |
| 394 # define USE_HASH_TABLE 1 | |
| 395 # define LOG_LEVEL1_SIZE 11 | |
| 396 #else | |
| 397 # define LOG_LEVEL1_SIZE \ | |
| 398 (BITS_PER_EMACS_INT - LOG_LEVEL2_SIZE - LOG_PAGE_SIZE) | |
| 399 #endif | |
| 400 #define LEVEL1_SIZE (1 << LOG_LEVEL1_SIZE) | |
| 401 | |
| 402 #ifdef USE_HASH_TABLE | |
| 403 # define HASH(hi) ((hi) & (LEVEL1_SIZE - 1)) | |
| 4125 | 404 # define L1_INDEX(p) HASH ((EMACS_UINT) p >> (LOG_LEVEL2_SIZE + LOG_PAGE_SIZE)) |
| 2720 | 405 #else |
| 4125 | 406 # define L1_INDEX(p) ((EMACS_UINT) p >> (LOG_LEVEL2_SIZE + LOG_PAGE_SIZE)) |
| 2720 | 407 #endif |
| 4125 | 408 #define L2_INDEX(p) (((EMACS_UINT) p >> LOG_PAGE_SIZE) & (LEVEL2_SIZE - 1)) |
| 2720 | 409 |
| 410 | |
| 411 | |
| 412 | |
| 413 /*--- structs and typedefs ---------------------------------------------*/ | |
| 414 | |
| 3092 | 415 /* Links the free lists (mark_bit_free_list and cell free list). */ |
| 2720 | 416 typedef struct free_link |
| 417 { | |
| 418 struct lrecord_header lheader; | |
| 419 struct free_link *next_free; | |
| 420 } free_link; | |
| 421 | |
| 422 | |
| 3092 | 423 /* Header for pages. They are held in a doubly linked list. */ |
| 2720 | 424 typedef struct page_header |
| 425 { | |
| 426 struct page_header *next; /* next page_header */ | |
| 427 struct page_header *prev; /* previous page_header */ | |
| 428 /* Field plh holds pointer to the according header of the page list.*/ | |
| 429 struct page_list_header *plh; /* page list header */ | |
| 430 free_link *free_list; /* links free cells on page */ | |
| 431 EMACS_INT n_pages; /* number of pages */ | |
| 432 EMACS_INT cell_size; /* size of cells on page */ | |
| 433 EMACS_INT cells_on_page; /* total number of cells on page */ | |
| 434 EMACS_INT cells_used; /* number of used cells on page */ | |
| 435 /* If the number of objects on page is bigger than BITS_PER_EMACS_INT, | |
| 436 the mark bits are put in an extra memory area. Then the field | |
| 437 mark_bits holds the pointer to this area. Is the number of | |
| 438 objects smaller than BITS_PER_EMACS_INT, the mark bits are held in the | |
| 439 mark_bit EMACS_INT directly, without an additional indirection. */ | |
| 3092 | 440 unsigned int black_bit:1; /* objects on page are black */ |
| 441 unsigned int dirty_bit:1; /* page is dirty */ | |
| 442 unsigned int protection_bit:1; /* page is write protected */ | |
| 443 unsigned int array_bit:1; /* page holds arrays */ | |
| 444 Rawbyte *mark_bits; /* pointer to mark bits */ | |
| 2720 | 445 void *heap_space; /* pointer to heap, where objects |
| 446 are stored */ | |
| 447 } page_header; | |
| 448 | |
| 449 | |
| 450 /* Different list types. */ | |
| 451 enum list_type_enum { | |
| 452 USED_LIST, | |
| 453 FREE_LIST | |
| 454 }; | |
| 455 | |
| 456 | |
| 457 /* Header for page lists. Field list_type holds the type of the list. */ | |
| 458 typedef struct page_list_header | |
| 459 { | |
| 460 enum list_type_enum list_type; /* the type of the list */ | |
| 461 /* Size holds the size of one cell (in bytes) in a used heap list, or the | |
| 462 size of the heap sector (in number of pages). */ | |
| 463 size_t size; /* size of one cell / heap sector */ | |
| 464 page_header *first; /* first of page_header list */ | |
| 465 page_header *last; /* last of page_header list */ | |
| 466 /* If the number of objects on page is bigger than | |
| 467 BITS_PER_EMACS_INT, the mark bits are put in an extra memory | |
| 468 area, which is linked in this free list, if not used. Is the | |
| 469 number of objects smaller than BITS_PER_EMACS_INT, the mark bits | |
| 470 are hold in the mark bit EMACS_INT directly, without an | |
| 471 additional indirection. */ | |
| 472 free_link *mark_bit_free_list; | |
| 473 | |
| 474 #ifdef MEMORY_USAGE_STATS | |
| 475 EMACS_INT page_count; /* number if pages in list */ | |
| 476 EMACS_INT used_cells; /* number of objects in list */ | |
| 477 EMACS_INT used_space; /* used space */ | |
| 478 EMACS_INT total_cells; /* number of available cells */ | |
| 479 EMACS_INT total_space; /* available space */ | |
| 480 #endif | |
| 481 } page_list_header; | |
| 482 | |
| 483 | |
| 484 /* The heap sectors are stored with their real start pointer and their | |
| 485 real size. Not aligned to PAGE_SIZE. Needed for freeing heap sectors. */ | |
| 486 typedef struct heap_sect { | |
| 487 void *real_start; /* real start pointer (NOT aligned) */ | |
| 488 size_t real_size; /* NOT multiple of PAGE_SIZE */ | |
| 489 void *start; /* aligned start pointer */ | |
| 490 EMACS_INT n_pages; /* multiple of PAGE_SIZE */ | |
| 491 } heap_sect; | |
| 492 | |
| 493 | |
| 494 /* 2nd tree level for mapping of heap addresses to page headers. */ | |
| 495 typedef struct level_2_lookup_tree { | |
| 496 page_header *index[LEVEL2_SIZE]; /* link to page header */ | |
| 497 EMACS_INT key; /* high order address bits */ | |
| 498 #ifdef USE_HASH_TABLE | |
| 499 struct level_2_lookup_tree *hash_link; /* hash chain link */ | |
| 500 #endif | |
| 501 } level_2_lookup_tree; | |
| 502 | |
| 503 | |
| 504 | |
| 505 /*--- global variable definitions --------------------------------------*/ | |
| 506 | |
| 507 /* All global allocator variables are kept in this struct. */ | |
| 508 typedef struct mc_allocator_globals_type { | |
| 509 | |
| 510 /* heap size */ | |
| 511 EMACS_INT heap_size; | |
| 512 | |
| 513 /* list of all separatly allocated chunks of heap */ | |
| 514 heap_sect heap_sections[MAX_HEAP_SECTS]; | |
| 515 EMACS_INT n_heap_sections; | |
| 516 | |
| 517 /* Holds all allocated pages, each object size class in its separate list, | |
| 518 to guarantee fast allocation on partially filled pages. */ | |
| 3092 | 519 page_list_header *used_heap_pages; |
| 2720 | 520 |
|
5216
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
521 /* Holds all allocated pages that contain array elements. */ |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
522 page_list_header array_heap_pages; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
523 |
| 2720 | 524 /* Holds all free pages in the heap. N multiples of PAGE_SIZE are |
| 525 kept on the Nth free list. Contiguos pages are coalesced. */ | |
| 526 page_list_header free_heap_pages[N_FREE_PAGE_LISTS]; | |
| 527 | |
| 528 /* ptr lookup table */ | |
| 3092 | 529 level_2_lookup_tree **ptr_lookup_table; |
| 2720 | 530 |
| 3092 | 531 #ifndef BLOCKTYPE_ALLOC_PAGE_HEADER |
| 2720 | 532 /* page header free list */ |
| 533 free_link *page_header_free_list; | |
| 3092 | 534 #endif /* not BLOCKTYPE_ALLOC_PAGE_HEADER */ |
| 2720 | 535 |
| 536 #ifdef MEMORY_USAGE_STATS | |
| 537 EMACS_INT malloced_bytes; | |
| 538 #endif | |
| 539 } mc_allocator_globals_type; | |
| 540 | |
| 541 mc_allocator_globals_type mc_allocator_globals; | |
| 542 | |
| 543 | |
| 544 | |
| 545 | |
| 546 /*--- macro accessors --------------------------------------------------*/ | |
| 547 | |
| 548 #define USED_HEAP_PAGES(i) \ | |
| 549 ((page_list_header*) &mc_allocator_globals.used_heap_pages[i]) | |
| 550 | |
|
5216
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
551 #define ARRAY_HEAP_PAGES \ |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
552 ((page_list_header*) &mc_allocator_globals.array_heap_pages) |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
553 |
| 2720 | 554 #define FREE_HEAP_PAGES(i) \ |
| 555 ((page_list_header*) &mc_allocator_globals.free_heap_pages[i]) | |
| 556 | |
| 557 #define PLH(plh) plh | |
| 558 # define PLH_LIST_TYPE(plh) PLH (plh)->list_type | |
| 559 # define PLH_SIZE(plh) PLH (plh)->size | |
| 560 # define PLH_FIRST(plh) PLH (plh)->first | |
| 561 # define PLH_LAST(plh) PLH (plh)->last | |
| 562 # define PLH_MARK_BIT_FREE_LIST(plh) PLH (plh)->mark_bit_free_list | |
| 563 #ifdef MEMORY_USAGE_STATS | |
| 564 # define PLH_PAGE_COUNT(plh) PLH (plh)->page_count | |
| 565 # define PLH_USED_CELLS(plh) PLH (plh)->used_cells | |
| 566 # define PLH_USED_SPACE(plh) PLH (plh)->used_space | |
| 567 # define PLH_TOTAL_CELLS(plh) PLH (plh)->total_cells | |
| 568 # define PLH_TOTAL_SPACE(plh) PLH (plh)->total_space | |
| 569 #endif | |
| 570 | |
| 571 #define PH(ph) ph | |
| 572 # define PH_NEXT(ph) PH (ph)->next | |
| 573 # define PH_PREV(ph) PH (ph)->prev | |
| 574 # define PH_PLH(ph) PH (ph)->plh | |
| 575 # define PH_FREE_LIST(ph) PH (ph)->free_list | |
| 576 # define PH_N_PAGES(ph) PH (ph)->n_pages | |
| 577 # define PH_CELL_SIZE(ph) PH (ph)->cell_size | |
| 578 # define PH_CELLS_ON_PAGE(ph) PH (ph)->cells_on_page | |
| 579 # define PH_CELLS_USED(ph) PH (ph)->cells_used | |
| 3092 | 580 # define PH_BLACK_BIT(ph) PH (ph)->black_bit |
| 581 # define PH_DIRTY_BIT(ph) PH (ph)->dirty_bit | |
| 582 # define PH_PROTECTION_BIT(ph) PH (ph)->protection_bit | |
| 583 # define PH_ARRAY_BIT(ph) PH (ph)->array_bit | |
| 2720 | 584 # define PH_MARK_BITS(ph) PH (ph)->mark_bits |
| 585 # define PH_HEAP_SPACE(ph) PH (ph)->heap_space | |
| 586 #define PH_LIST_TYPE(ph) PLH_LIST_TYPE (PH_PLH (ph)) | |
| 587 #define PH_MARK_BIT_FREE_LIST(ph) PLH_MARK_BIT_FREE_LIST (PH_PLH (ph)) | |
| 588 | |
| 589 #define HEAP_SIZE mc_allocator_globals.heap_size | |
| 590 | |
| 591 #ifdef MEMORY_USAGE_STATS | |
| 592 # define MC_MALLOCED_BYTES mc_allocator_globals.malloced_bytes | |
| 593 #endif | |
| 594 | |
| 595 #define HEAP_SECTION(index) mc_allocator_globals.heap_sections[index] | |
| 596 #define N_HEAP_SECTIONS mc_allocator_globals.n_heap_sections | |
| 597 | |
| 3092 | 598 #ifndef BLOCKTYPE_ALLOC_PAGE_HEADER |
| 2720 | 599 #define PAGE_HEADER_FREE_LIST mc_allocator_globals.page_header_free_list |
| 3092 | 600 #endif /* not BLOCKTYPE_ALLOC_PAGE_HEADER */ |
| 2720 | 601 |
| 602 #define NEXT_FREE(free_list) ((free_link*) free_list)->next_free | |
| 603 #define FREE_LIST(free_list) (free_link*) (free_list) | |
| 604 | |
| 605 #define PTR_LOOKUP_TABLE(i) mc_allocator_globals.ptr_lookup_table[i] | |
| 606 #define LEVEL2(l2, i) l2->index[i] | |
| 607 # define LEVEL2_KEY(l2) l2->key | |
| 608 #ifdef USE_HASH_TABLE | |
| 609 # define LEVEL2_HASH_LINK(l2) l2->hash_link | |
| 610 #endif | |
| 611 | |
| 612 #if ZERO_MEM | |
| 613 # define ZERO_HEAP_SPACE(ph) \ | |
| 614 memset (PH_HEAP_SPACE (ph), '\0', PH_N_PAGES (ph) * PAGE_SIZE) | |
| 615 # define ZERO_PAGE_HEADER(ph) memset (ph, '\0', sizeof (page_header)) | |
| 616 #endif | |
| 617 | |
| 618 #define div_PAGE_SIZE(x) (x >> LOG_PAGE_SIZE) | |
| 619 #define mult_PAGE_SIZE(x) (x << LOG_PAGE_SIZE) | |
| 620 | |
| 621 #define BYTES_TO_PAGES(bytes) (div_PAGE_SIZE ((bytes + (PAGE_SIZE - 1)))) | |
| 622 | |
| 623 #define PAGE_SIZE_ALIGNMENT(address) \ | |
| 4125 | 624 (void *) ((((EMACS_UINT) (address)) + PAGE_SIZE) & ~(PAGE_SIZE - 1)) |
| 2720 | 625 |
| 626 #define PH_ON_FREE_LIST_P(ph) \ | |
| 627 (ph && PH_PLH (ph) && (PLH_LIST_TYPE (PH_PLH (ph)) == FREE_LIST)) | |
| 628 | |
| 629 #define PH_ON_USED_LIST_P(ph) \ | |
| 630 (ph && PH_PLH (ph) && (PLH_LIST_TYPE (PH_PLH (ph)) == USED_LIST)) | |
| 631 | |
| 632 | |
| 3092 | 633 /* Number of mark bits: minimum 1, maximum 8. */ |
| 634 #define N_MARK_BITS 2 | |
| 2720 | 635 |
| 636 | |
| 637 | |
| 638 /************************************************************************/ | |
| 639 /* MC Allocator */ | |
| 640 /************************************************************************/ | |
| 641 | |
| 3305 | 642 /* Set to 1 if memory becomes short. */ |
| 643 EMACS_INT memory_shortage; | |
| 2720 | 644 |
| 645 /*--- misc functions ---------------------------------------------------*/ | |
| 646 | |
| 647 /* Visits all pages (page_headers) hooked into the used heap pages | |
| 648 list and executes f with the current page header as | |
| 3303 | 649 argument. Needed for sweep. Returns number of processed pages. */ |
| 650 static EMACS_INT | |
| 651 visit_all_used_page_headers (EMACS_INT (*f) (page_header *ph)) | |
| 2720 | 652 { |
| 3303 | 653 EMACS_INT number_of_pages_processed = 0; |
| 3092 | 654 EMACS_INT i; |
| 2720 | 655 for (i = 0; i < N_USED_PAGE_LISTS; i++) |
| 656 if (PLH_FIRST (USED_HEAP_PAGES (i))) | |
| 657 { | |
| 658 page_header *ph = PLH_FIRST (USED_HEAP_PAGES (i)); | |
| 659 while (PH_NEXT (ph)) | |
| 660 { | |
| 661 page_header *next = PH_NEXT (ph); /* in case f removes the page */ | |
| 3303 | 662 number_of_pages_processed += f (ph); |
| 2720 | 663 ph = next; |
| 664 } | |
| 3303 | 665 number_of_pages_processed += f (ph); |
| 2720 | 666 } |
|
5216
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
667 |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
668 if (PLH_FIRST (ARRAY_HEAP_PAGES)) |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
669 { |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
670 page_header *ph = PLH_FIRST (ARRAY_HEAP_PAGES); |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
671 while (PH_NEXT (ph)) |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
672 { |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
673 page_header *next = PH_NEXT (ph); /* in case f removes the page */ |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
674 number_of_pages_processed += f (ph); |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
675 ph = next; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
676 } |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
677 number_of_pages_processed += f (ph); |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
678 } |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
679 |
| 3303 | 680 return number_of_pages_processed; |
| 2720 | 681 } |
| 682 | |
| 683 | |
| 684 | |
| 685 | |
| 686 /*--- mapping of heap addresses to page headers and mark bits ----------*/ | |
| 687 | |
| 688 /* Sets a heap pointer and page header pair into the lookup table. */ | |
| 689 static void | |
| 690 set_lookup_table (void *ptr, page_header *ph) | |
| 691 { | |
| 3092 | 692 EMACS_INT l1_index = L1_INDEX (ptr); |
| 2720 | 693 level_2_lookup_tree *l2 = PTR_LOOKUP_TABLE (l1_index); |
| 694 #ifdef USE_HASH_TABLE | |
| 695 while ((l2) && (LEVEL2_KEY (l2) != l1_index)) | |
| 696 l2 = LEVEL2_HASH_LINK (l2); | |
| 697 #endif | |
| 698 if (!l2) | |
| 699 { | |
| 700 l2 = (level_2_lookup_tree*) | |
| 701 xmalloc_and_zero (sizeof (level_2_lookup_tree)); | |
| 702 #ifdef MEMORY_USAGE_STATS | |
| 703 MC_MALLOCED_BYTES += | |
| 704 malloced_storage_size (0, sizeof (level_2_lookup_tree), 0); | |
| 705 #endif | |
| 2932 | 706 memset (l2, '\0', sizeof (level_2_lookup_tree)); |
| 2720 | 707 #ifdef USE_HASH_TABLE |
| 708 LEVEL2_HASH_LINK (l2) = PTR_LOOKUP_TABLE (l1_index); | |
| 709 #endif | |
| 710 PTR_LOOKUP_TABLE (l1_index) = l2; | |
| 711 LEVEL2_KEY (l2) = l1_index; | |
| 712 } | |
| 713 LEVEL2 (l2, L2_INDEX (ptr)) = ph; | |
| 714 } | |
| 715 | |
| 716 | |
| 717 #ifdef UNSET_LOOKUP_TABLE | |
| 718 /* Set the lookup table to 0 for given heap address. */ | |
| 719 static void | |
| 720 unset_lookup_table (void *ptr) | |
| 721 { | |
| 3092 | 722 EMACS_INT l1_index = L1_INDEX (ptr); |
| 2720 | 723 level_2_lookup_tree *l2 = PTR_LOOKUP_TABLE (l1_index); |
| 724 #ifdef USE_HASH_TABLE | |
| 725 while ((l2) && (LEVEL2_KEY (l2) != l1_index)) | |
| 726 l2 = LEVEL2_HASH_LINK (l2); | |
| 727 #endif | |
| 728 if (l2) { | |
| 729 LEVEL2 (l2, L2_INDEX (ptr)) = 0; | |
| 730 } | |
| 731 } | |
| 732 #endif | |
| 733 | |
| 734 /* Returns the page header of a given heap address, or 0 if not in table. | |
| 735 For internal use, no error checking. */ | |
| 736 static page_header * | |
| 737 get_page_header_internal (void *ptr) | |
| 738 { | |
| 3092 | 739 EMACS_INT l1_index = L1_INDEX (ptr); |
| 2720 | 740 level_2_lookup_tree *l2 = PTR_LOOKUP_TABLE (l1_index); |
| 741 #ifdef USE_HASH_TABLE | |
| 742 while ((l2) && (LEVEL2_KEY (l2) != l1_index)) | |
| 743 l2 = LEVEL2_HASH_LINK (l2); | |
| 744 #endif | |
| 745 if (!l2) | |
| 746 return 0; | |
| 747 return LEVEL2 (l2, L2_INDEX (ptr)); | |
| 748 } | |
| 749 | |
| 750 /* Returns the page header of a given heap address, or 0 if not in table. */ | |
| 751 static page_header * | |
| 752 get_page_header (void *ptr) | |
| 753 { | |
| 3092 | 754 EMACS_INT l1_index = L1_INDEX (ptr); |
| 2720 | 755 level_2_lookup_tree *l2 = PTR_LOOKUP_TABLE (l1_index); |
| 2723 | 756 assert (l2); |
| 2720 | 757 #ifdef USE_HASH_TABLE |
| 758 while ((l2) && (LEVEL2_KEY (l2) != l1_index)) | |
| 759 l2 = LEVEL2_HASH_LINK (l2); | |
| 760 #endif | |
| 2723 | 761 assert (LEVEL2 (l2, L2_INDEX (ptr))); |
| 2720 | 762 return LEVEL2 (l2, L2_INDEX (ptr)); |
| 763 } | |
| 764 | |
| 765 /* Returns the mark bit index of a given heap address. */ | |
| 766 static EMACS_INT | |
| 767 get_mark_bit_index (void *ptr, page_header *ph) | |
| 768 { | |
| 769 EMACS_INT cell_size = PH_CELL_SIZE (ph); | |
| 770 if (cell_size) | |
| 3092 | 771 return (((EMACS_INT) ptr - (EMACS_INT)(PH_HEAP_SPACE (ph))) / cell_size) |
| 772 * N_MARK_BITS; | |
| 2720 | 773 else /* only one object on page */ |
| 774 return 0; | |
| 775 } | |
| 776 | |
| 777 | |
| 778 /* Adds addresses of pages to lookup table. */ | |
| 779 static void | |
| 780 add_pages_to_lookup_table (page_header *ph, EMACS_INT n_pages) | |
| 781 { | |
| 3092 | 782 Rawbyte *p = (Rawbyte *) PH_HEAP_SPACE (ph); |
| 2720 | 783 EMACS_INT end_of_section = (EMACS_INT) p + (PAGE_SIZE * n_pages); |
| 3092 | 784 for (p = (Rawbyte *) PH_HEAP_SPACE (ph); |
| 2720 | 785 (EMACS_INT) p < end_of_section; p += PAGE_SIZE) |
| 786 set_lookup_table (p, ph); | |
| 787 } | |
| 788 | |
| 789 | |
| 790 /* Initializes lookup table. */ | |
| 791 static void | |
| 792 init_lookup_table (void) | |
| 793 { | |
| 3092 | 794 EMACS_INT i; |
| 2720 | 795 for (i = 0; i < LEVEL1_SIZE; i++) |
| 796 PTR_LOOKUP_TABLE (i) = 0; | |
| 797 } | |
| 798 | |
| 799 | |
| 800 | |
| 801 | |
| 802 /*--- mark bits --------------------------------------------------------*/ | |
| 803 | |
| 804 /*--- bit operations --- */ | |
| 805 | |
| 806 /* Allocates a bit array of length bits. */ | |
| 3092 | 807 static Rawbyte * |
| 2720 | 808 alloc_bit_array(size_t bits) |
| 809 { | |
| 3092 | 810 Rawbyte *bit_array; |
| 811 #ifdef USE_MARK_BITS_FREE_LIST | |
| 812 size_t size = ((bits + CHAR_BIT - 1) / CHAR_BIT) * sizeof (Rawbyte); | |
| 813 #else /* not USE_MARK_BITS_FREE_LIST */ | |
| 814 size_t size = | |
| 815 ALIGN_FOR_TYPE (((bits + CHAR_BIT - 1) / CHAR_BIT) * sizeof (Rawbyte), | |
| 816 Rawbyte *); | |
| 817 #endif /* not USE_MARK_BITS_FREE_LIST */ | |
| 2720 | 818 if (size < sizeof (free_link)) size = sizeof (free_link); |
| 819 #ifdef MEMORY_USAGE_STATS | |
| 820 MC_MALLOCED_BYTES += malloced_storage_size (0, size, 0); | |
| 821 #endif | |
| 3092 | 822 bit_array = (Rawbyte *) xmalloc_and_zero (size); |
| 2720 | 823 return bit_array; |
| 824 } | |
| 825 | |
| 826 | |
| 827 /* Returns the bit value at pos. */ | |
| 828 static EMACS_INT | |
| 3092 | 829 get_bit (Rawbyte *bit_array, EMACS_INT pos) |
| 2720 | 830 { |
| 831 #if N_MARK_BITS > 1 | |
| 832 EMACS_INT result = 0; | |
| 833 EMACS_INT i; | |
| 834 #endif | |
| 835 bit_array += pos / CHAR_BIT; | |
| 836 #if N_MARK_BITS > 1 | |
| 837 for (i = 0; i < N_MARK_BITS; i++) | |
| 3092 | 838 result |= ((*bit_array & (1 << ((pos + i) % CHAR_BIT))) != 0) << i; |
| 839 return result; | |
| 2720 | 840 #else |
| 841 return (*bit_array & (1 << (pos % CHAR_BIT))) != 0; | |
| 842 #endif | |
| 843 } | |
| 844 | |
| 845 | |
| 846 /* Bit_Arrays bit at pos to val. */ | |
| 847 static void | |
| 4125 | 848 set_bit (Rawbyte *bit_array, EMACS_INT pos, EMACS_UINT val) |
| 2720 | 849 { |
| 850 #if N_MARK_BITS > 1 | |
| 851 EMACS_INT i; | |
| 852 #endif | |
| 853 bit_array += pos / CHAR_BIT; | |
| 854 #if N_MARK_BITS > 1 | |
| 855 for (i = 0; i < N_MARK_BITS; i++) | |
| 856 if ((val >> i) & 1) | |
| 857 *bit_array |= 1 << ((pos + i) % CHAR_BIT); | |
| 858 else | |
| 859 *bit_array &= ~(1 << ((pos + i) % CHAR_BIT)); | |
| 860 #else | |
| 861 if (val) | |
| 862 *bit_array |= 1 << (pos % CHAR_BIT); | |
| 863 else | |
| 864 *bit_array &= ~(1 << (pos % CHAR_BIT)); | |
| 865 #endif | |
| 866 } | |
| 867 | |
| 868 | |
| 869 /*--- mark bit functions ---*/ | |
| 3092 | 870 #define USE_PNTR_MARK_BITS(ph) \ |
| 871 ((PH_CELLS_ON_PAGE (ph) * N_MARK_BITS) > BITS_PER_EMACS_INT) | |
| 872 #define USE_WORD_MARK_BITS(ph) \ | |
| 873 ((PH_CELLS_ON_PAGE (ph) * N_MARK_BITS) <= BITS_PER_EMACS_INT) | |
| 2720 | 874 |
| 3092 | 875 #define GET_BIT_WORD(b, p) get_bit ((Rawbyte *) &b, p) |
| 2720 | 876 #define GET_BIT_PNTR(b, p) get_bit (b, p) |
| 877 | |
| 3092 | 878 #define SET_BIT_WORD(b, p, v) set_bit ((Rawbyte *) &b, p, v) |
| 2720 | 879 #define SET_BIT_PNTR(b, p, v) set_bit (b, p, v) |
| 880 | |
| 881 #define ZERO_MARK_BITS_WORD(ph) PH_MARK_BITS (ph) = 0 | |
| 3092 | 882 #define ZERO_MARK_BITS_PNTR(ph) \ |
| 883 do { \ | |
| 884 memset (PH_MARK_BITS (ph), '\0', \ | |
| 885 ((PH_CELLS_ON_PAGE (ph) * N_MARK_BITS) \ | |
| 886 + CHAR_BIT - 1) / CHAR_BIT * sizeof (Rawbyte)); \ | |
| 2720 | 887 } while (0) |
| 888 | |
| 889 #define GET_BIT(bit, ph, p) \ | |
| 890 do { \ | |
| 891 if (USE_PNTR_MARK_BITS (ph)) \ | |
| 892 bit = GET_BIT_PNTR (PH_MARK_BITS (ph), p); \ | |
| 893 else \ | |
| 894 bit = GET_BIT_WORD (PH_MARK_BITS (ph), p); \ | |
| 895 } while (0) | |
| 896 | |
| 897 #define SET_BIT(ph, p, v) \ | |
| 898 do { \ | |
| 899 if (USE_PNTR_MARK_BITS (ph)) \ | |
| 900 SET_BIT_PNTR (PH_MARK_BITS (ph), p, v); \ | |
| 901 else \ | |
| 902 SET_BIT_WORD (PH_MARK_BITS (ph), p, v); \ | |
| 903 } while (0) | |
| 904 | |
| 905 #define ZERO_MARK_BITS(ph) \ | |
| 906 do { \ | |
| 907 if (USE_PNTR_MARK_BITS (ph)) \ | |
| 908 ZERO_MARK_BITS_PNTR (ph); \ | |
| 909 else \ | |
| 910 ZERO_MARK_BITS_WORD (ph); \ | |
| 911 } while (0) | |
| 912 | |
| 913 | |
| 914 /* Allocates mark-bit space either from a free list or from the OS | |
| 915 for the given page header. */ | |
| 3092 | 916 static Rawbyte * |
| 2720 | 917 alloc_mark_bits (page_header *ph) |
| 918 { | |
| 3092 | 919 Rawbyte *result; |
| 920 #ifdef USE_MARK_BITS_FREE_LIST | |
| 2720 | 921 if (PH_MARK_BIT_FREE_LIST (ph) == 0) |
| 3092 | 922 result = (Rawbyte *) alloc_bit_array (PH_CELLS_ON_PAGE (ph) * N_MARK_BITS); |
| 2720 | 923 else |
| 924 { | |
| 3092 | 925 result = (Rawbyte *) PH_MARK_BIT_FREE_LIST (ph); |
| 2720 | 926 PH_MARK_BIT_FREE_LIST (ph) = NEXT_FREE (result); |
| 927 } | |
| 3092 | 928 #else /* not USE_MARK_BITS_FREE_LIST */ |
| 929 result = (Rawbyte *) alloc_bit_array (PH_CELLS_ON_PAGE (ph) * N_MARK_BITS); | |
| 930 #endif /* not USE_MARK_BITS_FREE_LIST */ | |
| 2720 | 931 return result; |
| 932 } | |
| 933 | |
| 934 | |
| 935 /* Frees by maintaining a free list. */ | |
| 936 static void | |
| 937 free_mark_bits (page_header *ph) | |
| 938 { | |
| 3092 | 939 #ifdef USE_MARK_BITS_FREE_LIST |
| 940 NEXT_FREE (PH_MARK_BITS (ph)) = PH_MARK_BIT_FREE_LIST (ph); | |
| 941 PH_MARK_BIT_FREE_LIST (ph) = FREE_LIST (PH_MARK_BITS (ph)); | |
| 942 #else /* not USE_MARK_BITS_FREE_LIST */ | |
| 2720 | 943 if (PH_MARK_BITS (ph)) |
| 3092 | 944 free (PH_MARK_BITS (ph)); |
| 945 #endif /* not USE_MARK_BITS_FREE_LIST */ | |
| 2720 | 946 } |
| 947 | |
| 948 | |
| 949 /* Installs mark bits and zeros bits. */ | |
| 950 static void | |
| 951 install_mark_bits (page_header *ph) | |
| 952 { | |
| 953 if (USE_PNTR_MARK_BITS (ph)) | |
| 954 { | |
| 955 PH_MARK_BITS (ph) = alloc_mark_bits (ph); | |
| 956 ZERO_MARK_BITS_PNTR (ph); | |
| 957 } | |
| 958 else | |
| 959 ZERO_MARK_BITS_WORD (ph); | |
| 960 } | |
| 961 | |
| 962 | |
| 963 /* Cleans and frees the mark bits of the given page_header. */ | |
| 964 static void | |
| 965 remove_mark_bits (page_header *ph) | |
| 966 { | |
| 967 if (USE_PNTR_MARK_BITS (ph)) | |
| 968 free_mark_bits (ph); | |
| 969 } | |
| 970 | |
| 971 | |
| 972 /* Zeros all mark bits in given header. */ | |
| 973 static void | |
| 974 zero_mark_bits (page_header *ph) | |
| 975 { | |
| 976 ZERO_MARK_BITS (ph); | |
| 977 } | |
| 978 | |
| 979 | |
| 980 /* Returns mark bit for given heap pointer. */ | |
| 981 EMACS_INT | |
| 982 get_mark_bit (void *ptr) | |
| 983 { | |
| 984 EMACS_INT bit = 0; | |
| 985 page_header *ph = get_page_header (ptr); | |
| 986 gc_checking_assert (ph && PH_ON_USED_LIST_P (ph)); | |
| 987 if (ph) | |
| 988 { | |
| 989 GET_BIT (bit, ph, get_mark_bit_index (ptr, ph)); | |
| 990 } | |
| 991 return bit; | |
| 992 } | |
| 993 | |
| 994 | |
| 995 /* Sets mark bit for given heap pointer. */ | |
| 996 void | |
| 997 set_mark_bit (void *ptr, EMACS_INT value) | |
| 998 { | |
| 999 page_header *ph = get_page_header (ptr); | |
| 1000 assert (ph && PH_ON_USED_LIST_P (ph)); | |
| 1001 if (ph) | |
| 1002 { | |
| 3092 | 1003 if (value == BLACK) |
| 1004 if (!PH_BLACK_BIT (ph)) | |
| 1005 PH_BLACK_BIT (ph) = 1; | |
| 2720 | 1006 SET_BIT (ph, get_mark_bit_index (ptr, ph), value); |
| 1007 } | |
| 1008 } | |
| 1009 | |
| 1010 | |
| 1011 | |
| 1012 | |
| 1013 /*--- page header functions --------------------------------------------*/ | |
| 1014 | |
| 3092 | 1015 #ifdef BLOCKTYPE_ALLOC_PAGE_HEADER |
| 1016 #include "blocktype.h" | |
| 1017 | |
| 1018 struct page_header_blocktype | |
| 1019 { | |
| 1020 Blocktype_declare (page_header); | |
| 1021 } *the_page_header_blocktype; | |
| 1022 #endif /* BLOCKTYPE_ALLOC_PAGE_HEADER */ | |
| 1023 | |
| 2720 | 1024 /* Allocates a page header either from a free list or from the OS. */ |
| 1025 static page_header * | |
| 1026 alloc_page_header (void) | |
| 1027 { | |
| 3092 | 1028 #ifdef BLOCKTYPE_ALLOC_PAGE_HEADER |
| 1029 page_header *result; | |
| 1030 #ifdef MEMORY_USAGE_STATS | |
| 1031 MC_MALLOCED_BYTES += malloced_storage_size (0, sizeof (page_header), 0); | |
| 1032 #endif | |
| 1033 result = Blocktype_alloc (the_page_header_blocktype); | |
| 1034 ZERO_PAGE_HEADER (result); | |
| 1035 return result; | |
| 1036 #else /* not BLOCKTYPE_ALLOC_PAGE_HEADER */ | |
| 2720 | 1037 page_header *result; |
| 1038 if (PAGE_HEADER_FREE_LIST == 0) | |
| 1039 { | |
| 1040 result = | |
| 1041 (page_header *) xmalloc_and_zero ((EMACS_INT) (sizeof (page_header))); | |
| 1042 #ifdef MEMORY_USAGE_STATS | |
| 1043 MC_MALLOCED_BYTES += malloced_storage_size (0, sizeof (page_header), 0); | |
| 1044 #endif | |
| 1045 } | |
| 1046 else | |
| 1047 { | |
| 1048 result = (page_header*) PAGE_HEADER_FREE_LIST; | |
| 1049 PAGE_HEADER_FREE_LIST = NEXT_FREE (result); | |
| 1050 } | |
| 1051 return result; | |
| 3092 | 1052 #endif /* not BLOCKTYPE_ALLOC_PAGE_HEADER */ |
| 2720 | 1053 } |
| 1054 | |
| 1055 | |
| 1056 /* Frees given page header by maintaining a free list. */ | |
| 1057 static void | |
| 1058 free_page_header (page_header *ph) | |
| 1059 { | |
| 3092 | 1060 #ifdef BLOCKTYPE_ALLOC_PAGE_HEADER |
| 1061 Blocktype_free (the_page_header_blocktype, ph); | |
| 1062 #else /* not BLOCKTYPE_ALLOC_PAGE_HEADER */ | |
| 2720 | 1063 #if ZERO_MEM |
| 1064 ZERO_PAGE_HEADER (ph); | |
| 1065 #endif | |
| 1066 NEXT_FREE (ph) = PAGE_HEADER_FREE_LIST; | |
| 1067 PAGE_HEADER_FREE_LIST = FREE_LIST (ph); | |
| 3092 | 1068 #endif /* not BLOCKTYPE_ALLOC_PAGE_HEADER */ |
| 2720 | 1069 } |
| 1070 | |
| 1071 | |
| 1072 /* Adds given page header to given page list header's list. */ | |
| 1073 static void | |
| 1074 add_page_header_to_plh (page_header *ph, page_list_header *plh) | |
| 1075 { | |
| 1076 /* insert at the front of the list */ | |
| 1077 PH_PREV (ph) = 0; | |
| 1078 PH_NEXT (ph) = PLH_FIRST (plh); | |
| 1079 PH_PLH (ph) = plh; | |
| 1080 /* if list is not empty, set prev in the first element */ | |
| 1081 if (PLH_FIRST (plh)) | |
| 1082 PH_PREV (PLH_FIRST (plh)) = ph; | |
| 1083 /* one element in list is first and last at the same time */ | |
| 1084 PLH_FIRST (plh) = ph; | |
| 1085 if (!PLH_LAST (plh)) | |
| 1086 PLH_LAST (plh) = ph; | |
| 1087 | |
| 1088 #ifdef MEMORY_USAGE_STATS | |
| 1089 /* bump page count */ | |
| 1090 PLH_PAGE_COUNT (plh)++; | |
| 1091 #endif | |
| 1092 | |
| 1093 } | |
| 1094 | |
| 1095 | |
| 1096 /* Removes given page header from given page list header's list. */ | |
| 1097 static void | |
| 1098 remove_page_header_from_plh (page_header *ph, page_list_header *plh) | |
| 1099 { | |
| 1100 if (PLH_FIRST (plh) == ph) | |
| 1101 PLH_FIRST (plh) = PH_NEXT (ph); | |
| 1102 if (PLH_LAST (plh) == ph) | |
| 1103 PLH_LAST (plh) = PH_PREV (ph); | |
| 1104 if (PH_NEXT (ph)) | |
| 1105 PH_PREV (PH_NEXT (ph)) = PH_PREV (ph); | |
| 1106 if (PH_PREV (ph)) | |
| 1107 PH_NEXT (PH_PREV (ph)) = PH_NEXT (ph); | |
| 1108 | |
| 1109 #ifdef MEMORY_USAGE_STATS | |
| 1110 /* decrease page count */ | |
| 1111 PLH_PAGE_COUNT (plh)--; | |
| 1112 #endif | |
| 1113 } | |
| 1114 | |
| 1115 | |
| 1116 /* Moves a page header to the front of its the page header list. | |
| 1117 This is used during sweep: Pages with some alive objects are moved to | |
| 1118 the front. This makes allocation faster, all pages with free slots | |
| 1119 can be found at the front of the list. */ | |
| 1120 static void | |
| 1121 move_page_header_to_front (page_header *ph) | |
| 1122 { | |
| 1123 page_list_header *plh = PH_PLH (ph); | |
| 1124 /* is page already first? */ | |
| 1125 if (ph == PLH_FIRST (plh)) return; | |
| 1126 /* remove from list */ | |
| 1127 if (PLH_LAST (plh) == ph) | |
| 1128 PLH_LAST (plh) = PH_PREV (ph); | |
| 1129 if (PH_NEXT (ph)) | |
| 1130 PH_PREV (PH_NEXT (ph)) = PH_PREV (ph); | |
| 1131 if (PH_PREV (ph)) | |
| 1132 PH_NEXT (PH_PREV (ph)) = PH_NEXT (ph); | |
| 1133 /* insert at the front */ | |
| 1134 PH_NEXT (ph) = PLH_FIRST (plh); | |
| 1135 PH_PREV (ph) = 0; | |
| 1136 PH_PREV (PH_NEXT (ph)) = ph; | |
| 1137 PLH_FIRST (plh) = ph; | |
| 1138 } | |
| 1139 | |
| 1140 | |
| 1141 | |
| 1142 | |
| 1143 /*--- page list functions ----------------------------------------------*/ | |
| 1144 | |
| 1145 /* Returns the index of the used heap list according to given size. */ | |
| 1146 static int | |
| 1147 get_used_list_index (size_t size) | |
| 1148 { | |
| 1149 if (size <= USED_LIST_MIN_OBJECT_SIZE) | |
| 3092 | 1150 { |
| 1151 // printf ("size %d -> index %d\n", size, 0); | |
| 1152 return 0; | |
| 1153 } | |
| 1154 if (size <= (size_t) USED_LIST_UPPER_THRESHOLD) | |
| 1155 { | |
| 1156 // printf ("size %d -> index %d\n", size, | |
| 1157 // ((size - USED_LIST_MIN_OBJECT_SIZE - 1) | |
| 1158 // / USED_LIST_LIN_STEP) + 1); | |
| 1159 return ((size - USED_LIST_MIN_OBJECT_SIZE - 1) | |
| 1160 / USED_LIST_LIN_STEP) + 1; | |
| 1161 } | |
| 1162 // printf ("size %d -> index %d\n", size, N_USED_PAGE_LISTS - 1); | |
| 2720 | 1163 return N_USED_PAGE_LISTS - 1; |
| 1164 } | |
| 1165 | |
| 1166 /* Returns the size of the used heap list according to given index. */ | |
| 1167 static size_t | |
| 1168 get_used_list_size_value (int used_index) | |
| 1169 { | |
| 1170 if (used_index < N_USED_PAGE_LISTS - 1) | |
| 1171 return (used_index * USED_LIST_LIN_STEP) + USED_LIST_MIN_OBJECT_SIZE; | |
| 1172 return 0; | |
| 1173 } | |
| 1174 | |
| 1175 | |
| 1176 /* Returns the index of the free heap list according to given size. */ | |
| 3092 | 1177 static EMACS_INT |
| 2720 | 1178 get_free_list_index (EMACS_INT n_pages) |
| 1179 { | |
| 1180 if (n_pages == 0) | |
| 1181 return 0; | |
| 1182 if (n_pages <= FREE_LIST_LOWER_THRESHOLD) | |
| 1183 return n_pages - 1; | |
| 1184 if (n_pages >= FREE_LIST_UPPER_THRESHOLD - 1) | |
| 1185 return N_FREE_PAGE_LISTS - 1; | |
| 1186 return ((n_pages - FREE_LIST_LOWER_THRESHOLD - 1) | |
| 1187 / FREE_LIST_LIN_STEP) + FREE_LIST_LOWER_THRESHOLD; | |
| 1188 | |
| 1189 } | |
| 1190 | |
| 1191 | |
| 1192 /* Returns the size in number of pages of the given free list at index. */ | |
| 1193 static size_t | |
| 3092 | 1194 get_free_list_size_value (EMACS_INT free_index) |
| 2720 | 1195 { |
| 1196 if (free_index < FREE_LIST_LOWER_THRESHOLD) | |
| 1197 return free_index + 1; | |
| 1198 if (free_index >= N_FREE_PAGE_LISTS) | |
| 1199 return FREE_LIST_UPPER_THRESHOLD; | |
| 1200 return ((free_index + 1 - FREE_LIST_LOWER_THRESHOLD) | |
| 1201 * FREE_LIST_LIN_STEP) + FREE_LIST_LOWER_THRESHOLD; | |
| 1202 } | |
| 1203 | |
| 1204 | |
| 1205 Bytecount | |
|
5157
1fae11d56ad2
redo memory-usage mechanism, add way of dynamically initializing Lisp objects
Ben Wing <ben@xemacs.org>
parents:
5146
diff
changeset
|
1206 mc_alloced_storage_size (Bytecount claimed_size, struct usage_stats *stats) |
| 2720 | 1207 { |
| 1208 size_t used_size = | |
| 1209 get_used_list_size_value (get_used_list_index (claimed_size)); | |
| 1210 if (used_size == 0) | |
| 1211 used_size = mult_PAGE_SIZE (BYTES_TO_PAGES (claimed_size)); | |
| 1212 | |
| 1213 if (stats) | |
| 1214 { | |
| 1215 stats->was_requested += claimed_size; | |
| 1216 stats->malloc_overhead += used_size - claimed_size; | |
| 1217 } | |
| 1218 | |
| 1219 return used_size; | |
| 1220 } | |
| 1221 | |
| 1222 | |
| 1223 | |
| 1224 /*--- free heap functions ----------------------------------------------*/ | |
| 1225 | |
| 1226 /* Frees a heap section, if the heap_section is completly free */ | |
| 1227 static EMACS_INT | |
| 1228 free_heap_section (page_header *ph) | |
| 1229 { | |
| 3092 | 1230 EMACS_INT i; |
| 1231 EMACS_INT removed = 0; | |
| 2720 | 1232 for (i = 0; i < N_HEAP_SECTIONS; i++) |
| 1233 if (!removed) | |
| 1234 { | |
| 1235 if ((PH_HEAP_SPACE (ph) == HEAP_SECTION(i).start) | |
| 1236 && (PH_N_PAGES (ph) == HEAP_SECTION(i).n_pages)) | |
| 1237 { | |
| 1238 xfree_1 (HEAP_SECTION(i).real_start); | |
| 1239 #ifdef MEMORY_USAGE_STATS | |
| 1240 MC_MALLOCED_BYTES | |
| 1241 -= malloced_storage_size (0, HEAP_SECTION(i).real_size, 0); | |
| 1242 #endif | |
| 1243 | |
| 1244 HEAP_SIZE -= PH_N_PAGES (ph) * PAGE_SIZE; | |
| 1245 | |
| 1246 removed = 1; | |
| 1247 } | |
| 1248 } | |
| 1249 else | |
| 1250 { | |
| 1251 HEAP_SECTION(i-1).real_start = HEAP_SECTION(i).real_start; | |
| 1252 HEAP_SECTION(i-1).real_size = HEAP_SECTION(i).real_size; | |
| 1253 HEAP_SECTION(i-1).start = HEAP_SECTION(i).start; | |
| 1254 HEAP_SECTION(i-1).n_pages = HEAP_SECTION(i).n_pages; | |
| 1255 } | |
| 1256 | |
| 1257 N_HEAP_SECTIONS = N_HEAP_SECTIONS - removed; | |
| 1258 | |
| 1259 return removed; | |
| 1260 } | |
| 1261 | |
| 1262 /* Removes page from free list. */ | |
| 1263 static void | |
| 1264 remove_page_from_free_list (page_header *ph) | |
| 1265 { | |
| 1266 remove_page_header_from_plh (ph, PH_PLH (ph)); | |
| 1267 PH_PLH (ph) = 0; | |
| 1268 } | |
| 1269 | |
| 1270 | |
| 1271 /* Adds page to according free list. */ | |
| 1272 static void | |
| 1273 add_page_to_free_list (page_header *ph) | |
| 1274 { | |
| 1275 PH_PLH (ph) = FREE_HEAP_PAGES (get_free_list_index (PH_N_PAGES (ph))); | |
| 1276 add_page_header_to_plh (ph, PH_PLH (ph)); | |
| 1277 } | |
| 1278 | |
| 1279 | |
| 1280 /* Merges two adjacent pages. */ | |
| 1281 static page_header * | |
| 1282 merge_pages (page_header *first_ph, page_header *second_ph) | |
| 1283 { | |
| 1284 /* merge */ | |
| 1285 PH_N_PAGES (first_ph) += PH_N_PAGES (second_ph); | |
| 1286 /* clean up left over page header */ | |
| 1287 free_page_header (second_ph); | |
| 1288 /* update lookup table */ | |
| 1289 add_pages_to_lookup_table (first_ph, PH_N_PAGES (first_ph)); | |
| 1290 | |
| 1291 return first_ph; | |
| 1292 } | |
| 1293 | |
| 1294 | |
| 1295 /* Checks if pages are adjacent, merges them, and adds merged page to | |
| 1296 free list */ | |
| 1297 static void | |
| 1298 merge_into_free_list (page_header *ph) | |
| 1299 { | |
| 1300 /* check if you can coalesce adjacent pages */ | |
| 1301 page_header *prev_ph = | |
| 1302 get_page_header_internal ((void*) (((EMACS_INT) PH_HEAP_SPACE (ph)) | |
| 1303 - PAGE_SIZE)); | |
| 1304 page_header *succ_ph = | |
| 1305 get_page_header_internal ((void*) (((EMACS_INT) PH_HEAP_SPACE (ph)) | |
| 1306 + (PH_N_PAGES (ph) * PAGE_SIZE))); | |
| 1307 if (PH_ON_FREE_LIST_P (prev_ph)) | |
| 1308 { | |
| 1309 remove_page_from_free_list (prev_ph); | |
| 1310 ph = merge_pages (prev_ph, ph); | |
| 1311 } | |
| 1312 if (PH_ON_FREE_LIST_P (succ_ph)) | |
| 1313 { | |
| 1314 remove_page_from_free_list (succ_ph); | |
| 1315 ph = merge_pages (ph, succ_ph); | |
| 1316 } | |
| 1317 /* try to free heap_section, if the section is complete */ | |
| 1318 if (!free_heap_section (ph)) | |
| 1319 /* else add merged page to free list */ | |
| 1320 add_page_to_free_list (ph); | |
| 1321 } | |
| 1322 | |
| 1323 | |
| 1324 /* Cuts given page header after n_pages, returns the first (cut) part, and | |
| 1325 puts the rest on the free list. */ | |
| 1326 static page_header * | |
| 1327 split_page (page_header *ph, EMACS_INT n_pages) | |
| 1328 { | |
| 1329 page_header *new_ph; | |
| 1330 EMACS_INT rem_pages = PH_N_PAGES (ph) - n_pages; | |
| 1331 | |
| 1332 /* remove the page from the free list if already hooked in */ | |
| 1333 if (PH_PLH (ph)) | |
| 1334 remove_page_from_free_list (ph); | |
| 1335 /* set new number of pages */ | |
| 1336 PH_N_PAGES (ph) = n_pages; | |
| 1337 /* add new page to lookup table */ | |
| 1338 add_pages_to_lookup_table (ph, n_pages); | |
| 1339 | |
| 1340 if (rem_pages) | |
| 1341 { | |
| 1342 /* build new page with reminder */ | |
| 1343 new_ph = alloc_page_header (); | |
| 1344 PH_N_PAGES (new_ph) = rem_pages; | |
| 1345 PH_HEAP_SPACE (new_ph) = | |
| 1346 (void*) ((EMACS_INT) (PH_HEAP_SPACE (ph)) + (n_pages * PAGE_SIZE)); | |
| 1347 /* add new page to lookup table */ | |
| 1348 add_pages_to_lookup_table (new_ph, rem_pages); | |
| 1349 /* hook the rest into free list */ | |
| 1350 add_page_to_free_list (new_ph); | |
| 1351 } | |
| 1352 return ph; | |
| 1353 } | |
| 1354 | |
| 1355 | |
| 1356 /* Expands the heap by given number of pages. */ | |
| 1357 static page_header * | |
| 1358 expand_heap (EMACS_INT needed_pages) | |
| 1359 { | |
| 1360 page_header *ph; | |
| 1361 EMACS_INT n_pages; | |
| 1362 size_t real_size; | |
| 1363 void *real_start; | |
| 1364 | |
| 1365 /* determine number of pages the heap should grow */ | |
| 3305 | 1366 if (memory_shortage) |
| 1367 n_pages = needed_pages; | |
| 1368 else | |
| 1369 n_pages = max (MIN_HEAP_INCREASE, | |
| 1370 needed_pages | |
| 1371 + (HEAP_SIZE / (PAGE_SIZE * HEAP_GROWTH_DIVISOR))); | |
| 2720 | 1372 |
| 1373 /* get the real values */ | |
| 1374 real_size = (n_pages * PAGE_SIZE) + PAGE_SIZE; | |
| 1375 real_start = xmalloc_and_zero (real_size); | |
| 1376 #ifdef MEMORY_USAGE_STATS | |
| 1377 MC_MALLOCED_BYTES += malloced_storage_size (0, real_size, 0); | |
| 1378 #endif | |
| 1379 | |
| 1380 /* maintain heap section count */ | |
| 1381 if (N_HEAP_SECTIONS >= MAX_HEAP_SECTS) | |
| 1382 { | |
| 1383 stderr_out ("Increase number of MAX_HEAP_SECTS"); | |
| 1384 ABORT (); | |
| 1385 } | |
| 1386 HEAP_SECTION(N_HEAP_SECTIONS).real_start = real_start; | |
| 1387 HEAP_SECTION(N_HEAP_SECTIONS).real_size = real_size; | |
| 1388 HEAP_SECTION(N_HEAP_SECTIONS).start = PAGE_SIZE_ALIGNMENT (real_start); | |
| 1389 HEAP_SECTION(N_HEAP_SECTIONS).n_pages = n_pages; | |
| 1390 N_HEAP_SECTIONS ++; | |
| 1391 | |
| 1392 /* get page header */ | |
| 1393 ph = alloc_page_header (); | |
| 1394 | |
| 1395 /* setup page header */ | |
| 1396 PH_N_PAGES (ph) = n_pages; | |
| 1397 PH_HEAP_SPACE (ph) = PAGE_SIZE_ALIGNMENT (real_start); | |
| 1398 assert (((EMACS_INT) (PH_HEAP_SPACE (ph)) % PAGE_SIZE) == 0); | |
| 1399 HEAP_SIZE += n_pages * PAGE_SIZE; | |
| 1400 | |
| 1401 /* this was also done by allocate_lisp_storage */ | |
| 1402 if (need_to_check_c_alloca) | |
| 1403 xemacs_c_alloca (0); | |
| 1404 | |
| 1405 /* return needed size, put rest on free list */ | |
| 1406 return split_page (ph, needed_pages); | |
| 1407 } | |
| 1408 | |
| 1409 | |
| 1410 | |
| 1411 | |
| 1412 /*--- used heap functions ----------------------------------------------*/ | |
| 1413 /* Installs initial free list. */ | |
| 1414 static void | |
|
5216
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1415 install_cell_free_list (page_header *ph) |
| 2720 | 1416 { |
| 3092 | 1417 Rawbyte *p; |
| 1418 EMACS_INT i; | |
| 2720 | 1419 EMACS_INT cell_size = PH_CELL_SIZE (ph); |
| 1420 /* write initial free list if cell_size is < PAGE_SIZE */ | |
| 3092 | 1421 p = (Rawbyte *) PH_HEAP_SPACE (ph); |
| 2720 | 1422 for (i = 0; i < PH_CELLS_ON_PAGE (ph) - 1; i++) |
| 1423 { | |
| 1424 #ifdef ERROR_CHECK_GC | |
| 1425 assert (!LRECORD_FREE_P (p)); | |
| 1426 MARK_LRECORD_AS_FREE (p); | |
| 1427 #endif | |
|
5216
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1428 if (!PH_ARRAY_BIT (ph)) |
| 3092 | 1429 NEXT_FREE (p) = FREE_LIST (p + cell_size); |
| 2720 | 1430 set_lookup_table (p, ph); |
| 3092 | 1431 p += cell_size; |
| 2720 | 1432 } |
| 1433 #ifdef ERROR_CHECK_GC | |
| 1434 assert (!LRECORD_FREE_P (p)); | |
| 1435 MARK_LRECORD_AS_FREE (p); | |
| 1436 #endif | |
| 1437 NEXT_FREE (p) = 0; | |
| 1438 set_lookup_table (p, ph); | |
| 1439 | |
| 1440 /* hook free list into header */ | |
| 1441 PH_FREE_LIST (ph) = FREE_LIST (PH_HEAP_SPACE (ph)); | |
| 1442 } | |
| 1443 | |
| 1444 | |
| 1445 /* Cleans the object space of the given page_header. */ | |
| 1446 static void | |
| 1447 remove_cell_free_list (page_header *ph) | |
| 1448 { | |
| 1449 #if ZERO_MEM | |
| 1450 ZERO_HEAP_SPACE (ph); | |
| 1451 #endif | |
| 1452 PH_FREE_LIST (ph) = 0; | |
| 1453 } | |
| 1454 | |
| 1455 | |
| 1456 /* Installs a new page and hooks it into given page_list_header. */ | |
| 1457 static page_header * | |
| 1458 install_page_in_used_list (page_header *ph, page_list_header *plh, | |
| 3092 | 1459 size_t size, EMACS_INT elemcount) |
| 2720 | 1460 { |
| 1461 /* add to list */ | |
| 1462 add_page_header_to_plh (ph, plh); | |
| 1463 | |
| 1464 /* determine cell size */ | |
| 1465 if (PLH_SIZE (plh)) | |
| 1466 PH_CELL_SIZE (ph) = PLH_SIZE (plh); | |
| 1467 else | |
| 1468 PH_CELL_SIZE (ph) = size; | |
| 3092 | 1469 if (elemcount == 1) |
|
5216
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1470 { |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1471 PH_CELLS_ON_PAGE (ph) = (PAGE_SIZE * PH_N_PAGES (ph)) / PH_CELL_SIZE (ph); |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1472 PH_ARRAY_BIT (ph) = 0; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1473 } |
| 3092 | 1474 else |
| 1475 { | |
| 1476 PH_CELLS_ON_PAGE (ph) = elemcount; | |
| 1477 PH_ARRAY_BIT (ph) = 1; | |
| 1478 } | |
| 2720 | 1479 |
| 1480 /* init cell count */ | |
| 1481 PH_CELLS_USED (ph) = 0; | |
| 1482 | |
| 1483 /* install mark bits and initialize cell free list */ | |
| 3092 | 1484 install_mark_bits (ph); |
| 2720 | 1485 |
|
5216
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1486 install_cell_free_list (ph); |
| 2720 | 1487 |
| 1488 #ifdef MEMORY_USAGE_STATS | |
| 1489 PLH_TOTAL_CELLS (plh) += PH_CELLS_ON_PAGE (ph); | |
| 1490 PLH_TOTAL_SPACE (plh) += PAGE_SIZE * PH_N_PAGES (ph); | |
| 1491 #endif | |
| 1492 | |
| 1493 return ph; | |
| 1494 } | |
| 1495 | |
| 1496 | |
| 1497 /* Cleans and frees a page, identified by the given page_header. */ | |
| 1498 static void | |
| 1499 remove_page_from_used_list (page_header *ph) | |
| 1500 { | |
| 1501 page_list_header *plh = PH_PLH (ph); | |
| 1502 | |
|
5050
6f2158fa75ed
Fix quick-build, use asserts() in place of ABORT()
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
1503 assert (!(gc_in_progress && PH_PROTECTION_BIT (ph))); |
| 3092 | 1504 /* cleanup: remove memory protection, zero page_header bits. */ |
| 1505 | |
| 2720 | 1506 #ifdef MEMORY_USAGE_STATS |
| 1507 PLH_TOTAL_CELLS (plh) -= PH_CELLS_ON_PAGE (ph); | |
| 1508 PLH_TOTAL_SPACE (plh) -= PAGE_SIZE * PH_N_PAGES (ph); | |
| 1509 #endif | |
| 1510 | |
| 1511 /* clean up mark bits and cell free list */ | |
| 1512 remove_cell_free_list (ph); | |
| 1513 if (PH_ON_USED_LIST_P (ph)) | |
| 1514 remove_mark_bits (ph); | |
| 1515 | |
| 1516 /* clean up page header */ | |
| 1517 PH_CELL_SIZE (ph) = 0; | |
| 1518 PH_CELLS_ON_PAGE (ph) = 0; | |
| 1519 PH_CELLS_USED (ph) = 0; | |
| 1520 | |
| 1521 /* remove from used list */ | |
| 1522 remove_page_header_from_plh (ph, plh); | |
| 1523 | |
| 1524 /* move to free list */ | |
| 1525 merge_into_free_list (ph); | |
| 1526 } | |
| 1527 | |
| 1528 | |
| 1529 | |
| 1530 | |
| 1531 /*--- allocation -------------------------------------------------------*/ | |
| 1532 | |
| 1533 /* Allocates from cell free list on already allocated pages. */ | |
| 1534 static page_header * | |
| 1535 allocate_cell (page_list_header *plh) | |
| 1536 { | |
| 1537 page_header *ph = PLH_FIRST (plh); | |
| 1538 if (ph) | |
| 1539 { | |
| 1540 if (PH_FREE_LIST (ph)) | |
| 1541 /* elements free on first page */ | |
| 1542 return ph; | |
| 1543 else if ((PH_NEXT (ph)) | |
| 1544 && (PH_FREE_LIST (PH_NEXT (ph)))) | |
| 1545 /* elements free on second page */ | |
| 1546 { | |
| 1547 page_header *temp = PH_NEXT (ph); | |
| 1548 /* move full page (first page) to end of list */ | |
| 1549 PH_NEXT (PLH_LAST (plh)) = ph; | |
| 1550 PH_PREV (ph) = PLH_LAST (plh); | |
| 1551 PLH_LAST (plh) = ph; | |
| 1552 PH_NEXT (ph) = 0; | |
| 1553 /* install second page as first page */ | |
| 1554 ph = temp; | |
| 1555 PH_PREV (ph) = 0; | |
| 1556 PLH_FIRST (plh) = ph; | |
| 1557 return ph; | |
| 1558 } | |
| 1559 } | |
| 1560 return 0; | |
| 1561 } | |
| 1562 | |
| 1563 | |
| 1564 /* Finds a page which has at least the needed number of pages. | |
| 1565 Algorithm: FIRST FIT. */ | |
| 1566 static page_header * | |
| 1567 find_free_page_first_fit (EMACS_INT needed_pages, page_header *ph) | |
| 1568 { | |
| 1569 while (ph) | |
| 1570 { | |
| 1571 if (PH_N_PAGES (ph) >= needed_pages) | |
| 1572 return ph; | |
| 1573 ph = PH_NEXT (ph); | |
| 1574 } | |
| 1575 return 0; | |
| 1576 } | |
| 1577 | |
| 1578 | |
| 1579 /* Allocates a page from the free list. */ | |
| 1580 static page_header * | |
| 1581 allocate_page_from_free_list (EMACS_INT needed_pages) | |
| 1582 { | |
| 1583 page_header *ph = 0; | |
| 3092 | 1584 EMACS_INT i; |
| 2720 | 1585 for (i = get_free_list_index (needed_pages); i < N_FREE_PAGE_LISTS; i++) |
| 1586 if ((ph = find_free_page_first_fit (needed_pages, | |
| 1587 PLH_FIRST (FREE_HEAP_PAGES (i)))) != 0) | |
| 1588 { | |
| 1589 if (PH_N_PAGES (ph) > needed_pages) | |
| 1590 return split_page (ph, needed_pages); | |
| 1591 else | |
| 1592 { | |
| 1593 remove_page_from_free_list (ph); | |
| 1594 return ph; | |
| 1595 } | |
| 1596 } | |
| 1597 return 0; | |
| 1598 } | |
| 1599 | |
| 1600 | |
| 1601 /* Allocates a new page, either from free list or by expanding the heap. */ | |
| 1602 static page_header * | |
| 3092 | 1603 allocate_new_page (page_list_header *plh, size_t size, EMACS_INT elemcount) |
| 2720 | 1604 { |
| 3092 | 1605 EMACS_INT needed_pages = BYTES_TO_PAGES (size * elemcount); |
| 2720 | 1606 /* first check free list */ |
| 1607 page_header *result = allocate_page_from_free_list (needed_pages); | |
| 1608 if (!result) | |
| 1609 /* expand heap */ | |
| 1610 result = expand_heap (needed_pages); | |
| 3092 | 1611 install_page_in_used_list (result, plh, size, elemcount); |
| 2720 | 1612 return result; |
| 1613 } | |
| 1614 | |
| 1615 | |
| 1616 /* Selects the correct size class, tries to allocate a cell of this size | |
| 1617 from the free list, if this fails, a new page is allocated. */ | |
| 1618 static void * | |
| 3092 | 1619 mc_alloc_1 (size_t size, EMACS_INT elemcount) |
| 2720 | 1620 { |
| 1621 page_list_header *plh = 0; | |
| 2723 | 1622 page_header *ph = 0; |
| 1623 void *result = 0; | |
| 1624 | |
| 2720 | 1625 if (size == 0) |
| 1626 return 0; | |
|
5216
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1627 |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1628 if (elemcount == 1) |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1629 { |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1630 plh = USED_HEAP_PAGES (get_used_list_index (size)); |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1631 if (size < (size_t) USED_LIST_UPPER_THRESHOLD) |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1632 /* first check any free cells */ |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1633 ph = allocate_cell (plh); |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1634 } |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1635 else |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1636 { |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1637 plh = ARRAY_HEAP_PAGES; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1638 } |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1639 |
| 2720 | 1640 if (!ph) |
| 1641 /* allocate a new page */ | |
| 3092 | 1642 ph = allocate_new_page (plh, size, elemcount); |
| 2720 | 1643 |
| 1644 /* return first element of free list and remove it from the list */ | |
| 1645 result = (void*) PH_FREE_LIST (ph); | |
| 1646 PH_FREE_LIST (ph) = | |
| 1647 NEXT_FREE (PH_FREE_LIST (ph)); | |
| 1648 | |
| 3092 | 1649 memset (result, '\0', (size * elemcount)); |
| 1650 MARK_LRECORD_AS_FREE (result); | |
| 2720 | 1651 |
| 1652 /* bump used cells counter */ | |
| 3092 | 1653 PH_CELLS_USED (ph) += elemcount; |
| 2720 | 1654 |
| 1655 #ifdef MEMORY_USAGE_STATS | |
| 3092 | 1656 PLH_USED_CELLS (plh) += elemcount; |
| 1657 PLH_USED_SPACE (plh) += size * elemcount; | |
| 2720 | 1658 #endif |
| 1659 | |
| 1660 return result; | |
| 1661 } | |
| 1662 | |
| 3092 | 1663 /* Array allocation. */ |
| 1664 void * | |
| 1665 mc_alloc_array (size_t size, EMACS_INT elemcount) | |
| 1666 { | |
| 1667 return mc_alloc_1 (size, elemcount); | |
| 1668 } | |
| 1669 | |
| 2720 | 1670 void * |
| 1671 mc_alloc (size_t size) | |
| 1672 { | |
| 1673 return mc_alloc_1 (size, 1); | |
| 1674 } | |
| 1675 | |
| 1676 | |
| 1677 | |
| 1678 /*--- sweep & free & finalize-------------------------------------------*/ | |
| 1679 | |
| 1680 /* Frees a heap pointer. */ | |
| 1681 static void | |
| 1682 remove_cell (void *ptr, page_header *ph) | |
| 1683 { | |
| 1684 #ifdef MEMORY_USAGE_STATS | |
| 1685 PLH_USED_CELLS (PH_PLH (ph))--; | |
| 1686 if (PH_ON_USED_LIST_P (ph)) | |
| 1687 PLH_USED_SPACE (PH_PLH (ph)) -= | |
| 1688 detagged_lisp_object_size ((const struct lrecord_header *) ptr); | |
| 1689 else | |
| 1690 PLH_USED_SPACE (PH_PLH (ph)) -= PH_CELL_SIZE (ph); | |
| 1691 #endif | |
| 2775 | 1692 if (PH_ON_USED_LIST_P (ph)) |
| 1693 { | |
| 2994 | 1694 #ifdef ALLOC_TYPE_STATS |
| 2775 | 1695 dec_lrecord_stats (PH_CELL_SIZE (ph), |
| 1696 (const struct lrecord_header *) ptr); | |
| 2994 | 1697 #endif /* ALLOC_TYPE_STATS */ |
| 2775 | 1698 #ifdef ERROR_CHECK_GC |
| 1699 assert (!LRECORD_FREE_P (ptr)); | |
| 1700 deadbeef_memory (ptr, PH_CELL_SIZE (ph)); | |
| 1701 MARK_LRECORD_AS_FREE (ptr); | |
| 2720 | 1702 #endif |
| 2775 | 1703 } |
| 2720 | 1704 |
| 1705 /* hooks cell into free list */ | |
| 1706 NEXT_FREE (ptr) = PH_FREE_LIST (ph); | |
| 1707 PH_FREE_LIST (ph) = FREE_LIST (ptr); | |
| 1708 /* decrease cells used */ | |
| 1709 PH_CELLS_USED (ph)--; | |
| 1710 } | |
| 1711 | |
| 1712 | |
| 1713 /* Mark free list marks all free list entries. */ | |
| 1714 static void | |
| 1715 mark_free_list (page_header *ph) | |
| 1716 { | |
| 1717 free_link *fl = PH_FREE_LIST (ph); | |
| 1718 while (fl) | |
| 1719 { | |
| 3092 | 1720 SET_BIT (ph, get_mark_bit_index (fl, ph), BLACK); |
| 2720 | 1721 fl = NEXT_FREE (fl); |
| 1722 } | |
| 1723 } | |
| 1724 | |
| 1725 | |
| 1726 /* Finalize a page for disksave. XEmacs calls this routine before it | |
| 1727 dumps the heap image. You have to tell mc-alloc how to call your | |
| 1728 object's finalizer for disksave. Therefore, you have to define the | |
| 1729 macro MC_ALLOC_CALL_FINALIZER_FOR_DISKSAVE(ptr). This macro should | |
| 1730 do nothing else then test if there is a finalizer and call it on | |
| 3303 | 1731 the given argument, which is the heap address of the object. |
| 1732 Returns number of processed pages. */ | |
| 1733 static EMACS_INT | |
| 2720 | 1734 finalize_page_for_disksave (page_header *ph) |
| 1735 { | |
| 1736 EMACS_INT heap_space = (EMACS_INT) PH_HEAP_SPACE (ph); | |
| 1737 EMACS_INT heap_space_step = PH_CELL_SIZE (ph); | |
| 1738 EMACS_INT mark_bit = 0; | |
| 1739 EMACS_INT mark_bit_max_index = PH_CELLS_ON_PAGE (ph); | |
| 1740 | |
| 1741 for (mark_bit = 0; mark_bit < mark_bit_max_index; mark_bit++) | |
| 1742 { | |
| 1743 EMACS_INT ptr = (heap_space + (heap_space_step * mark_bit)); | |
| 1744 MC_ALLOC_CALL_FINALIZER_FOR_DISKSAVE ((void *) ptr); | |
| 1745 } | |
| 3303 | 1746 return 1; |
| 2720 | 1747 } |
| 1748 | |
| 1749 | |
| 3303 | 1750 /* Finalizes the heap for disksave. Returns number of processed |
| 1751 pages. */ | |
| 1752 EMACS_INT | |
| 2720 | 1753 mc_finalize_for_disksave (void) |
| 1754 { | |
| 3303 | 1755 return visit_all_used_page_headers (finalize_page_for_disksave); |
| 2720 | 1756 } |
| 1757 | |
| 1758 | |
| 3303 | 1759 /* Sweeps a page: all the non-marked cells are freed. If the page is |
| 1760 empty in the end, it is removed. If some cells are free, it is | |
| 1761 moved to the front of its page header list. Full pages stay where | |
| 1762 they are. Returns number of processed pages.*/ | |
| 1763 static EMACS_INT | |
| 2720 | 1764 sweep_page (page_header *ph) |
| 1765 { | |
| 3092 | 1766 Rawbyte *heap_space = (Rawbyte *) PH_HEAP_SPACE (ph); |
| 2720 | 1767 EMACS_INT heap_space_step = PH_CELL_SIZE (ph); |
| 1768 EMACS_INT mark_bit = 0; | |
| 1769 EMACS_INT mark_bit_max_index = PH_CELLS_ON_PAGE (ph); | |
| 3092 | 1770 unsigned int bit = 0; |
| 2720 | 1771 |
| 1772 mark_free_list (ph); | |
| 1773 | |
| 3092 | 1774 /* ARRAY_BIT_HACK */ |
| 1775 if (PH_ARRAY_BIT (ph)) | |
| 1776 for (mark_bit = 0; mark_bit < mark_bit_max_index; mark_bit++) | |
| 1777 { | |
| 1778 GET_BIT (bit, ph, mark_bit * N_MARK_BITS); | |
| 1779 if (bit) | |
| 1780 { | |
| 1781 zero_mark_bits (ph); | |
| 1782 PH_BLACK_BIT (ph) = 0; | |
| 3303 | 1783 return 1; |
| 3092 | 1784 } |
| 1785 } | |
| 1786 | |
| 2720 | 1787 for (mark_bit = 0; mark_bit < mark_bit_max_index; mark_bit++) |
| 1788 { | |
| 3092 | 1789 GET_BIT (bit, ph, mark_bit * N_MARK_BITS); |
| 1790 if (bit == WHITE) | |
| 2720 | 1791 { |
| 3092 | 1792 GC_STAT_FREED; |
| 2720 | 1793 remove_cell (heap_space + (heap_space_step * mark_bit), ph); |
| 1794 } | |
| 1795 } | |
| 1796 zero_mark_bits (ph); | |
| 3092 | 1797 PH_BLACK_BIT (ph) = 0; |
| 2720 | 1798 if (PH_CELLS_USED (ph) == 0) |
| 1799 remove_page_from_used_list (ph); | |
| 1800 else if (PH_CELLS_USED (ph) < PH_CELLS_ON_PAGE (ph)) | |
| 1801 move_page_header_to_front (ph); | |
| 3303 | 1802 |
| 1803 return 1; | |
| 2720 | 1804 } |
| 1805 | |
| 1806 | |
| 3303 | 1807 /* Sweeps the heap. Returns number of processed pages. */ |
| 1808 EMACS_INT | |
| 2720 | 1809 mc_sweep (void) |
| 1810 { | |
| 3303 | 1811 return visit_all_used_page_headers (sweep_page); |
| 2720 | 1812 } |
| 1813 | |
| 1814 | |
| 1815 /* Changes the size of the cell pointed to by ptr. | |
| 1816 Returns the new address of the new cell with new size. */ | |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
1817 static void * |
| 3092 | 1818 mc_realloc_1 (void *ptr, size_t size, int elemcount) |
| 2720 | 1819 { |
| 1820 if (ptr) | |
| 1821 { | |
| 3092 | 1822 if (size * elemcount) |
| 2720 | 1823 { |
| 3092 | 1824 void *result = mc_alloc_1 (size, elemcount); |
| 2720 | 1825 size_t from_size = PH_CELL_SIZE (get_page_header (ptr)); |
| 3092 | 1826 size_t cpy_size = size * elemcount; |
| 1827 if (cpy_size > from_size) | |
| 2720 | 1828 cpy_size = from_size; |
| 1829 memcpy (result, ptr, cpy_size); | |
| 3092 | 1830 #ifdef ALLOC_TYPE_STATS |
| 1831 inc_lrecord_stats (size, (struct lrecord_header *) result); | |
| 1832 #endif /* not ALLOC_TYPE_STATS */ | |
| 2720 | 1833 return result; |
| 1834 } | |
| 1835 else | |
| 1836 { | |
| 1837 return 0; | |
| 1838 } | |
| 1839 } | |
| 1840 else | |
| 3092 | 1841 return mc_alloc_1 (size, elemcount); |
| 2720 | 1842 } |
| 1843 | |
| 1844 void * | |
| 1845 mc_realloc (void *ptr, size_t size) | |
| 1846 { | |
| 1847 return mc_realloc_1 (ptr, size, 1); | |
| 1848 } | |
| 1849 | |
| 1850 void * | |
| 3092 | 1851 mc_realloc_array (void *ptr, size_t size, EMACS_INT elemcount) |
| 2720 | 1852 { |
| 3092 | 1853 return mc_realloc_1 (ptr, size, elemcount); |
| 2720 | 1854 } |
| 1855 | |
| 1856 | |
| 1857 | |
| 1858 /*--- initialization ---------------------------------------------------*/ | |
| 1859 | |
| 1860 /* Call once at the very beginning. */ | |
| 1861 void | |
| 1862 init_mc_allocator (void) | |
| 1863 { | |
| 3092 | 1864 EMACS_INT i; |
| 1865 | |
| 1866 #ifdef MEMORY_USAGE_STATS | |
| 1867 MC_MALLOCED_BYTES = 0; | |
| 1868 #endif | |
| 2720 | 1869 |
| 3092 | 1870 /* init of pagesize dependent values */ |
| 1871 switch (SYS_PAGE_SIZE) | |
| 1872 { | |
| 1873 case 512: log_page_size = 9; break; | |
| 1874 case 1024: log_page_size = 10; break; | |
| 1875 case 2048: log_page_size = 11; break; | |
| 1876 case 4096: log_page_size = 12; break; | |
| 1877 case 8192: log_page_size = 13; break; | |
| 1878 case 16384: log_page_size = 14; break; | |
| 3212 | 1879 case 32768: log_page_size = 15; break; |
| 1880 case 65536: log_page_size = 16; break; | |
| 1881 default: | |
| 1882 fprintf(stderr, "##### SYS_PAGE_SIZE=%d not supported #####\n", | |
| 1883 SYS_PAGE_SIZE); | |
| 1884 ABORT (); | |
| 3092 | 1885 } |
| 1886 | |
| 4125 | 1887 page_size_div_2 = (EMACS_UINT) SYS_PAGE_SIZE >> 1; |
| 3092 | 1888 |
| 1889 mc_allocator_globals.used_heap_pages = | |
| 1890 (page_list_header *) xmalloc_and_zero ((N_USED_PAGE_LISTS + 1) | |
| 1891 * sizeof (page_list_header)); | |
| 1892 #ifdef MEMORY_USAGE_STATS | |
| 1893 MC_MALLOCED_BYTES += (N_USED_PAGE_LISTS + 1) * sizeof (page_list_header); | |
| 1894 #endif | |
| 1895 | |
| 1896 mc_allocator_globals.ptr_lookup_table = | |
| 1897 (level_2_lookup_tree **) | |
| 1898 xmalloc_and_zero ((LEVEL1_SIZE + 1) * sizeof (level_2_lookup_tree *)); | |
| 1899 #ifdef MEMORY_USAGE_STATS | |
| 1900 MC_MALLOCED_BYTES += (LEVEL1_SIZE + 1) * sizeof (level_2_lookup_tree *); | |
| 1901 #endif | |
| 1902 | |
| 1903 #ifdef BLOCKTYPE_ALLOC_PAGE_HEADER | |
| 1904 the_page_header_blocktype = Blocktype_new (struct page_header_blocktype); | |
| 1905 #endif /* BLOCKTYPE_ALLOC_PAGE_HEADER */ | |
| 2932 | 1906 |
| 2720 | 1907 for (i = 0; i < N_USED_PAGE_LISTS; i++) |
| 1908 { | |
| 1909 page_list_header *plh = USED_HEAP_PAGES (i); | |
| 1910 PLH_LIST_TYPE (plh) = USED_LIST; | |
| 1911 PLH_SIZE (plh) = get_used_list_size_value (i); | |
| 1912 PLH_FIRST (plh) = 0; | |
| 1913 PLH_LAST (plh) = 0; | |
| 1914 PLH_MARK_BIT_FREE_LIST (plh) = 0; | |
| 1915 #ifdef MEMORY_USAGE_STATS | |
| 1916 PLH_PAGE_COUNT (plh) = 0; | |
| 1917 PLH_USED_CELLS (plh) = 0; | |
| 1918 PLH_USED_SPACE (plh) = 0; | |
| 1919 PLH_TOTAL_CELLS (plh) = 0; | |
| 1920 PLH_TOTAL_SPACE (plh) = 0; | |
| 1921 #endif | |
| 1922 } | |
| 1923 | |
|
5216
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1924 { |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1925 page_list_header *plh = ARRAY_HEAP_PAGES; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1926 PLH_LIST_TYPE (plh) = USED_LIST; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1927 PLH_SIZE (plh) = 0; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1928 PLH_FIRST (plh) = 0; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1929 PLH_LAST (plh) = 0; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1930 PLH_MARK_BIT_FREE_LIST (plh) = 0; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1931 #ifdef MEMORY_USAGE_STATS |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1932 PLH_PAGE_COUNT (plh) = 0; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1933 PLH_USED_CELLS (plh) = 0; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1934 PLH_USED_SPACE (plh) = 0; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1935 PLH_TOTAL_CELLS (plh) = 0; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1936 PLH_TOTAL_SPACE (plh) = 0; |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1937 #endif |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1938 } |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
1939 |
| 2720 | 1940 for (i = 0; i < N_FREE_PAGE_LISTS; i++) |
| 1941 { | |
| 1942 page_list_header *plh = FREE_HEAP_PAGES (i); | |
| 1943 PLH_LIST_TYPE (plh) = FREE_LIST; | |
| 1944 PLH_SIZE (plh) = get_free_list_size_value (i); | |
| 1945 PLH_FIRST (plh) = 0; | |
| 1946 PLH_LAST (plh) = 0; | |
| 1947 PLH_MARK_BIT_FREE_LIST (plh) = 0; | |
| 1948 #ifdef MEMORY_USAGE_STATS | |
| 1949 PLH_PAGE_COUNT (plh) = 0; | |
| 1950 PLH_USED_CELLS (plh) = 0; | |
| 1951 PLH_USED_SPACE (plh) = 0; | |
| 1952 PLH_TOTAL_CELLS (plh) = 0; | |
| 1953 PLH_TOTAL_SPACE (plh) = 0; | |
| 1954 #endif | |
| 1955 } | |
| 1956 | |
| 3092 | 1957 #ifndef BLOCKTYPE_ALLOC_PAGE_HEADER |
| 2720 | 1958 PAGE_HEADER_FREE_LIST = 0; |
| 3092 | 1959 #endif /* not BLOCKTYPE_ALLOC_PAGE_HEADER */ |
| 2720 | 1960 |
| 1961 #ifdef MEMORY_USAGE_STATS | |
| 3092 | 1962 MC_MALLOCED_BYTES += sizeof (mc_allocator_globals); |
| 2720 | 1963 #endif |
| 1964 | |
| 1965 init_lookup_table (); | |
| 1966 } | |
| 1967 | |
| 1968 | |
| 1969 | |
| 1970 | |
| 1971 /*--- lisp function for statistics -------------------------------------*/ | |
| 1972 | |
| 1973 #ifdef MEMORY_USAGE_STATS | |
| 1974 DEFUN ("mc-alloc-memory-usage", Fmc_alloc_memory_usage, 0, 0, 0, /* | |
| 1975 Returns stats about the mc-alloc memory usage. See diagnose.el. | |
| 1976 */ | |
| 1977 ()) | |
| 1978 { | |
| 1979 Lisp_Object free_plhs = Qnil; | |
| 1980 Lisp_Object used_plhs = Qnil; | |
| 1981 Lisp_Object heap_sects = Qnil; | |
| 3092 | 1982 EMACS_INT used_size = 0; |
| 1983 EMACS_INT real_size = 0; | |
| 2720 | 1984 |
| 3092 | 1985 EMACS_INT i; |
| 2720 | 1986 |
| 1987 for (i = 0; i < N_FREE_PAGE_LISTS; i++) | |
| 1988 if (PLH_PAGE_COUNT (FREE_HEAP_PAGES(i)) > 0) | |
| 1989 free_plhs = | |
| 1990 acons (make_int (PLH_SIZE (FREE_HEAP_PAGES(i))), | |
| 1991 list1 (make_int (PLH_PAGE_COUNT (FREE_HEAP_PAGES(i)))), | |
| 1992 free_plhs); | |
| 1993 | |
| 1994 for (i = 0; i < N_USED_PAGE_LISTS; i++) | |
| 1995 if (PLH_PAGE_COUNT (USED_HEAP_PAGES(i)) > 0) | |
| 1996 used_plhs = | |
| 1997 acons (make_int (PLH_SIZE (USED_HEAP_PAGES(i))), | |
| 1998 list5 (make_int (PLH_PAGE_COUNT (USED_HEAP_PAGES(i))), | |
| 1999 make_int (PLH_USED_CELLS (USED_HEAP_PAGES(i))), | |
| 2000 make_int (PLH_USED_SPACE (USED_HEAP_PAGES(i))), | |
| 2001 make_int (PLH_TOTAL_CELLS (USED_HEAP_PAGES(i))), | |
| 2002 make_int (PLH_TOTAL_SPACE (USED_HEAP_PAGES(i)))), | |
| 2003 used_plhs); | |
| 2004 | |
|
5216
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
2005 used_plhs = |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
2006 acons (make_int (0), |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
2007 list5 (make_int (PLH_PAGE_COUNT(ARRAY_HEAP_PAGES)), |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
2008 make_int (PLH_USED_CELLS (ARRAY_HEAP_PAGES)), |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
2009 make_int (PLH_USED_SPACE (ARRAY_HEAP_PAGES)), |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
2010 make_int (PLH_TOTAL_CELLS (ARRAY_HEAP_PAGES)), |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
2011 make_int (PLH_TOTAL_SPACE (ARRAY_HEAP_PAGES))), |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
2012 used_plhs); |
|
9b8c2168d231
Allocate lrecord arrays in own size class.
Marcus Crestani <crestani@informatik.uni-tuebingen.de>
parents:
5167
diff
changeset
|
2013 |
| 2720 | 2014 for (i = 0; i < N_HEAP_SECTIONS; i++) { |
| 2015 used_size += HEAP_SECTION(i).n_pages * PAGE_SIZE; | |
| 2016 real_size += | |
| 2017 malloced_storage_size (0, HEAP_SECTION(i).real_size, 0); | |
| 2018 } | |
| 2019 | |
| 2020 heap_sects = | |
| 2021 list3 (make_int (N_HEAP_SECTIONS), | |
| 2022 make_int (used_size), | |
| 2023 make_int (real_size)); | |
| 2024 | |
| 2025 return Fcons (make_int (PAGE_SIZE), | |
| 3092 | 2026 list5 (heap_sects, |
| 2720 | 2027 Fnreverse (used_plhs), |
| 2028 Fnreverse (free_plhs), | |
| 2029 make_int (sizeof (mc_allocator_globals)), | |
| 2030 make_int (MC_MALLOCED_BYTES))); | |
| 2031 } | |
| 2032 #endif /* MEMORY_USAGE_STATS */ | |
| 2033 | |
| 2034 void | |
| 2035 syms_of_mc_alloc (void) | |
| 2036 { | |
| 2037 #ifdef MEMORY_USAGE_STATS | |
| 2038 DEFSUBR (Fmc_alloc_memory_usage); | |
| 2039 #endif /* MEMORY_USAGE_STATS */ | |
| 2040 } | |
| 3092 | 2041 |
| 2042 | |
| 2043 /*--- incremental garbage collector ----------------------------------*/ | |
| 2044 | |
| 5054 | 2045 #if 0 /* currently unused */ |
| 2046 | |
| 3092 | 2047 /* access dirty bit of page header */ |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
2048 static void |
| 3092 | 2049 set_dirty_bit (page_header *ph, unsigned int value) |
| 2050 { | |
| 2051 PH_DIRTY_BIT (ph) = value; | |
| 2052 } | |
| 2053 | |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
2054 static void |
| 3092 | 2055 set_dirty_bit_for_address (void *ptr, unsigned int value) |
| 2056 { | |
| 2057 set_dirty_bit (get_page_header (ptr), value); | |
| 2058 } | |
| 2059 | |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
2060 static unsigned int |
| 3092 | 2061 get_dirty_bit (page_header *ph) |
| 2062 { | |
| 2063 return PH_DIRTY_BIT (ph); | |
| 2064 } | |
| 2065 | |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
2066 static unsigned int |
| 3092 | 2067 get_dirty_bit_for_address (void *ptr) |
| 2068 { | |
| 2069 return get_dirty_bit (get_page_header (ptr)); | |
| 2070 } | |
| 2071 | |
| 2072 | |
| 2073 /* access protection bit of page header */ | |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
2074 static void |
| 3092 | 2075 set_protection_bit (page_header *ph, unsigned int value) |
| 2076 { | |
| 2077 PH_PROTECTION_BIT (ph) = value; | |
| 2078 } | |
| 2079 | |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
2080 static void |
| 3092 | 2081 set_protection_bit_for_address (void *ptr, unsigned int value) |
| 2082 { | |
| 2083 set_protection_bit (get_page_header (ptr), value); | |
| 2084 } | |
| 2085 | |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
2086 static unsigned int |
| 3092 | 2087 get_protection_bit (page_header *ph) |
| 2088 { | |
| 2089 return PH_PROTECTION_BIT (ph); | |
| 2090 } | |
| 2091 | |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
2092 static unsigned int |
| 3092 | 2093 get_protection_bit_for_address (void *ptr) |
| 2094 { | |
| 2095 return get_protection_bit (get_page_header (ptr)); | |
| 2096 } | |
| 2097 | |
| 2098 | |
| 2099 /* Returns the start of the page of the object pointed to by ptr. */ | |
|
5042
f395ee7ad844
Fix some compile warnings, make vdb test code conditional on DEBUG_XEMACS
Ben Wing <ben@xemacs.org>
parents:
4125
diff
changeset
|
2100 static void * |
| 3092 | 2101 get_page_start (void *ptr) |
| 2102 { | |
| 2103 return PH_HEAP_SPACE (get_page_header (ptr)); | |
| 2104 } | |
| 2105 | |
| 5054 | 2106 #endif /* 0 */ |
| 2107 | |
| 3092 | 2108 /* Make PAGE_SIZE globally available. */ |
| 2109 EMACS_INT | |
| 2110 mc_get_page_size () | |
| 2111 { | |
| 2112 return PAGE_SIZE; | |
| 2113 } | |
| 2114 | |
| 2115 /* Is the fault at ptr on a protected page? */ | |
| 2116 EMACS_INT | |
| 2117 fault_on_protected_page (void *ptr) | |
| 2118 { | |
| 2119 page_header *ph = get_page_header_internal (ptr); | |
| 2120 return (ph | |
| 2121 && PH_HEAP_SPACE (ph) | |
| 2122 && (PH_HEAP_SPACE (ph) <= ptr) | |
| 2123 && ((void *) ((EMACS_INT) PH_HEAP_SPACE (ph) | |
| 2124 + PH_N_PAGES (ph) * PAGE_SIZE) > ptr) | |
| 2125 && (PH_PROTECTION_BIT (ph) == 1)); | |
| 2126 } | |
| 2127 | |
| 2128 | |
| 2129 /* Protect the heap page of given page header ph if black objects are | |
| 3303 | 2130 on the page. Returns number of processed pages. */ |
| 2131 static EMACS_INT | |
| 3092 | 2132 protect_heap_page (page_header *ph) |
| 2133 { | |
| 2134 if (PH_BLACK_BIT (ph)) | |
| 2135 { | |
| 2136 void *heap_space = PH_HEAP_SPACE (ph); | |
| 2137 EMACS_INT heap_space_size = PH_N_PAGES (ph) * PAGE_SIZE; | |
| 2138 vdb_protect ((void *) heap_space, heap_space_size); | |
| 2139 PH_PROTECTION_BIT (ph) = 1; | |
| 3303 | 2140 return 1; |
| 3092 | 2141 } |
| 3303 | 2142 return 0; |
| 3092 | 2143 } |
| 2144 | |
| 3303 | 2145 /* Protect all heap pages with black objects. Returns number of |
| 2146 processed pages.*/ | |
| 2147 EMACS_INT | |
| 3092 | 2148 protect_heap_pages (void) |
| 2149 { | |
| 3303 | 2150 return visit_all_used_page_headers (protect_heap_page); |
| 3092 | 2151 } |
| 2152 | |
| 2153 | |
| 2154 /* Remove protection (if there) of heap page of given page header | |
| 3303 | 2155 ph. Returns number of processed pages. */ |
| 2156 static EMACS_INT | |
| 3092 | 2157 unprotect_heap_page (page_header *ph) |
| 2158 { | |
| 2159 if (PH_PROTECTION_BIT (ph)) | |
| 2160 { | |
| 2161 void *heap_space = PH_HEAP_SPACE (ph); | |
| 2162 EMACS_INT heap_space_size = PH_N_PAGES (ph) * PAGE_SIZE; | |
| 2163 vdb_unprotect (heap_space, heap_space_size); | |
| 2164 PH_PROTECTION_BIT (ph) = 0; | |
| 3303 | 2165 return 1; |
| 3092 | 2166 } |
| 3303 | 2167 return 0; |
| 3092 | 2168 } |
| 2169 | |
| 3303 | 2170 /* Remove protection for all heap pages which are protected. Returns |
| 2171 number of processed pages. */ | |
| 2172 EMACS_INT | |
| 3092 | 2173 unprotect_heap_pages (void) |
| 2174 { | |
| 3303 | 2175 return visit_all_used_page_headers (unprotect_heap_page); |
| 3092 | 2176 } |
| 2177 | |
| 2178 /* Remove protection and mark page dirty. */ | |
| 2179 void | |
| 2180 unprotect_page_and_mark_dirty (void *ptr) | |
| 2181 { | |
| 2182 page_header *ph = get_page_header (ptr); | |
| 2183 unprotect_heap_page (ph); | |
| 2184 PH_DIRTY_BIT (ph) = 1; | |
| 2185 } | |
| 2186 | |
| 2187 /* Repush all objects on dirty pages onto the mark stack. */ | |
| 2188 int | |
| 2189 repush_all_objects_on_page (void *ptr) | |
| 2190 { | |
| 2191 int repushed_objects = 0; | |
| 2192 page_header *ph = get_page_header (ptr); | |
| 2193 Rawbyte *heap_space = (Rawbyte *) PH_HEAP_SPACE (ph); | |
| 2194 EMACS_INT heap_space_step = PH_CELL_SIZE (ph); | |
| 2195 EMACS_INT mark_bit = 0; | |
| 2196 EMACS_INT mark_bit_max_index = PH_CELLS_ON_PAGE (ph); | |
| 2197 unsigned int bit = 0; | |
| 2198 for (mark_bit = 0; mark_bit < mark_bit_max_index; mark_bit++) | |
| 2199 { | |
| 2200 GET_BIT (bit, ph, mark_bit * N_MARK_BITS); | |
| 2201 if (bit == BLACK) | |
| 2202 { | |
| 2203 repushed_objects++; | |
| 2204 gc_write_barrier | |
| 2205 (wrap_pointer_1 ((heap_space + (heap_space_step * mark_bit)))); | |
| 2206 } | |
| 2207 } | |
| 2208 PH_BLACK_BIT (ph) = 0; | |
| 2209 PH_DIRTY_BIT (ph) = 0; | |
| 2210 return repushed_objects; | |
| 2211 } | |
| 2212 | |
| 2213 /* Mark black if object is currently grey. This first checks, if the | |
| 2214 object is really allocated on the mc-heap. If it is, it can be | |
| 2215 marked black; if it is not, it cannot be marked. */ | |
| 2216 EMACS_INT | |
| 2217 maybe_mark_black (void *ptr) | |
| 2218 { | |
| 2219 page_header *ph = get_page_header_internal (ptr); | |
| 2220 unsigned int bit = 0; | |
| 2221 | |
| 2222 if (ph && PH_PLH (ph) && PH_ON_USED_LIST_P (ph)) | |
| 2223 { | |
| 2224 GET_BIT (bit, ph, get_mark_bit_index (ptr, ph)); | |
| 2225 if (bit == GREY) | |
| 2226 { | |
| 2227 if (!PH_BLACK_BIT (ph)) | |
| 2228 PH_BLACK_BIT (ph) = 1; | |
| 2229 SET_BIT (ph, get_mark_bit_index (ptr, ph), BLACK); | |
| 2230 } | |
| 2231 return 1; | |
| 2232 } | |
| 2233 return 0; | |
| 2234 } | |
| 2235 | |
| 2236 /* Only for debugging --- not used anywhere in the sources. */ | |
| 2237 EMACS_INT | |
| 2238 object_on_heap_p (void *ptr) | |
| 2239 { | |
| 2240 page_header *ph = get_page_header_internal (ptr); | |
| 2241 return (ph && PH_ON_USED_LIST_P (ph)); | |
| 2242 } |