1 It has been said that successful communication 1 It has been said that successful communication requires first identifying
2 what your audience knows and then building a b 2 what your audience knows and then building a bridge from their current
3 knowledge to what they need to know. Unfortun 3 knowledge to what they need to know. Unfortunately, the expected
4 Linux-kernel memory model (LKMM) audience migh 4 Linux-kernel memory model (LKMM) audience might be anywhere from novice
5 to expert both in kernel hacking and in unders 5 to expert both in kernel hacking and in understanding LKMM.
6 6
7 This document therefore points out a number of 7 This document therefore points out a number of places to start reading,
8 depending on what you know and what you would 8 depending on what you know and what you would like to learn. Please note
9 that the documents later in this list assume t 9 that the documents later in this list assume that the reader understands
10 the material provided by documents earlier in 10 the material provided by documents earlier in this list.
11 11
12 If LKMM-specific terms lost you, glossary.txt 12 If LKMM-specific terms lost you, glossary.txt might help you.
13 13
14 o You are new to Linux-kernel concurrenc 14 o You are new to Linux-kernel concurrency: simple.txt
15 15
16 o You have some background in Linux-kern 16 o You have some background in Linux-kernel concurrency, and would
17 like an overview of the types of low-l 17 like an overview of the types of low-level concurrency primitives
18 that the Linux kernel provides: order 18 that the Linux kernel provides: ordering.txt
19 19
20 Here, "low level" means atomic operati 20 Here, "low level" means atomic operations to single variables.
21 21
22 o You are familiar with the Linux-kernel 22 o You are familiar with the Linux-kernel concurrency primitives
23 that you need, and just want to get st 23 that you need, and just want to get started with LKMM litmus
24 tests: litmus-tests.txt 24 tests: litmus-tests.txt
25 25
26 o You would like to access lock-protecte 26 o You would like to access lock-protected shared variables without
27 having their corresponding locks held: 27 having their corresponding locks held: locking.txt
28 28
29 o You are familiar with Linux-kernel con 29 o You are familiar with Linux-kernel concurrency, and would
30 like a detailed intuitive understandin 30 like a detailed intuitive understanding of LKMM, including
31 situations involving more than two thr 31 situations involving more than two threads: recipes.txt
32 32
33 o You would like a detailed understandin 33 o You would like a detailed understanding of what your compiler can
34 and cannot do to control dependencies: 34 and cannot do to control dependencies: control-dependencies.txt
35 35
36 o You would like to mark concurrent norm 36 o You would like to mark concurrent normal accesses to shared
37 variables so that intentional "racy" a 37 variables so that intentional "racy" accesses can be properly
38 documented, especially when you are re 38 documented, especially when you are responding to complaints
39 from KCSAN: access-marking.txt 39 from KCSAN: access-marking.txt
40 40
41 o You are familiar with Linux-kernel con 41 o You are familiar with Linux-kernel concurrency and the use of
42 LKMM, and would like a quick reference 42 LKMM, and would like a quick reference: cheatsheet.txt
43 43
44 o You are familiar with Linux-kernel con 44 o You are familiar with Linux-kernel concurrency and the use
45 of LKMM, and would like to learn about 45 of LKMM, and would like to learn about LKMM's requirements,
46 rationale, and implementation: explan 46 rationale, and implementation: explanation.txt and
47 herd-representation.txt 47 herd-representation.txt
48 48
49 o You are interested in the publications 49 o You are interested in the publications related to LKMM, including
50 hardware manuals, academic literature, 50 hardware manuals, academic literature, standards-committee
51 working papers, and LWN articles: ref 51 working papers, and LWN articles: references.txt
52 52
53 53
54 ==================== 54 ====================
55 DESCRIPTION OF FILES 55 DESCRIPTION OF FILES
56 ==================== 56 ====================
57 57
58 README 58 README
59 This file. 59 This file.
60 60
61 access-marking.txt 61 access-marking.txt
62 Guidelines for marking intentionally c 62 Guidelines for marking intentionally concurrent accesses to
63 shared memory. 63 shared memory.
64 64
65 cheatsheet.txt 65 cheatsheet.txt
66 Quick-reference guide to the Linux-ker 66 Quick-reference guide to the Linux-kernel memory model.
67 67
68 control-dependencies.txt 68 control-dependencies.txt
69 Guide to preventing compiler optimizat 69 Guide to preventing compiler optimizations from destroying
70 your control dependencies. 70 your control dependencies.
71 71
72 explanation.txt 72 explanation.txt
73 Detailed description of the memory mod 73 Detailed description of the memory model.
74 74
75 glossary.txt 75 glossary.txt
76 Brief definitions of LKMM-related term 76 Brief definitions of LKMM-related terms.
77 77
78 herd-representation.txt 78 herd-representation.txt
79 The (abstract) representation of the L 79 The (abstract) representation of the Linux-kernel concurrency
80 primitives in terms of events. 80 primitives in terms of events.
81 81
82 litmus-tests.txt 82 litmus-tests.txt
83 The format, features, capabilities, an 83 The format, features, capabilities, and limitations of the litmus
84 tests that LKMM can evaluate. 84 tests that LKMM can evaluate.
85 85
86 locking.txt 86 locking.txt
87 Rules for accessing lock-protected sha 87 Rules for accessing lock-protected shared variables outside of
88 their corresponding critical sections. 88 their corresponding critical sections.
89 89
90 ordering.txt 90 ordering.txt
91 Overview of the Linux kernel's low-lev 91 Overview of the Linux kernel's low-level memory-ordering
92 primitives by category. 92 primitives by category.
93 93
94 recipes.txt 94 recipes.txt
95 Common memory-ordering patterns. 95 Common memory-ordering patterns.
96 96
97 references.txt 97 references.txt
98 Background information. 98 Background information.
99 99
100 simple.txt 100 simple.txt
101 Starting point for someone new to Linu 101 Starting point for someone new to Linux-kernel concurrency.
102 And also a reminder of the simpler app 102 And also a reminder of the simpler approaches to concurrency!
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