1This directory contains the following litmus tests:
2
3CoRR+poonceonce+Once.litmus
4	Test of read-read coherence, that is, whether or not two
5	successive reads from the same variable are ordered.
6
7CoRW+poonceonce+Once.litmus
8	Test of read-write coherence, that is, whether or not a read
9	from a given variable followed by a write to that same variable
10	are ordered.
11
12CoWR+poonceonce+Once.litmus
13	Test of write-read coherence, that is, whether or not a write
14	to a given variable followed by a read from that same variable
15	are ordered.
16
17CoWW+poonceonce.litmus
18	Test of write-write coherence, that is, whether or not two
19	successive writes to the same variable are ordered.
20
21IRIW+mbonceonces+OnceOnce.litmus
22	Test of independent reads from independent writes with smp_mb()
23	between each pairs of reads.  In other words, is smp_mb()
24	sufficient to cause two different reading processes to agree on
25	the order of a pair of writes, where each write is to a different
26	variable by a different process?
27
28IRIW+poonceonces+OnceOnce.litmus
29	Test of independent reads from independent writes with nothing
30	between each pairs of reads.  In other words, is anything at all
31	needed to cause two different reading processes to agree on the
32	order of a pair of writes, where each write is to a different
33	variable by a different process?
34
35ISA2+poonceonces.litmus
36	As below, but with store-release replaced with WRITE_ONCE()
37	and load-acquire replaced with READ_ONCE().
38
39ISA2+pooncerelease+poacquirerelease+poacquireonce.litmus
40	Can a release-acquire chain order a prior store against
41	a later load?
42
43LB+ctrlonceonce+mbonceonce.litmus
44	Does a control dependency and an smp_mb() suffice for the
45	load-buffering litmus test, where each process reads from one
46	of two variables then writes to the other?
47
48LB+poacquireonce+pooncerelease.litmus
49	Does a release-acquire pair suffice for the load-buffering
50	litmus test, where each process reads from one of two variables then
51	writes to the other?
52
53LB+poonceonces.litmus
54	As above, but with store-release replaced with WRITE_ONCE()
55	and load-acquire replaced with READ_ONCE().
56
57MP+onceassign+derefonce.litmus
58	As below, but with rcu_assign_pointer() and an rcu_dereference().
59
60MP+polocks.litmus
61	As below, but with the second access of the writer process
62	and the first access of reader process protected by a lock.
63
64MP+poonceonces.litmus
65	As below, but without the smp_rmb() and smp_wmb().
66
67MP+pooncerelease+poacquireonce.litmus
68	As below, but with a release-acquire chain.
69
70MP+porevlocks.litmus
71	As below, but with the first access of the writer process
72	and the second access of reader process protected by a lock.
73
74MP+wmbonceonce+rmbonceonce.litmus
75	Does a smp_wmb() (between the stores) and an smp_rmb() (between
76	the loads) suffice for the message-passing litmus test, where one
77	process writes data and then a flag, and the other process reads
78	the flag and then the data.  (This is similar to the ISA2 tests,
79	but with two processes instead of three.)
80
81R+mbonceonces.litmus
82	This is the fully ordered (via smp_mb()) version of one of
83	the classic counterintuitive litmus tests that illustrates the
84	effects of store propagation delays.
85
86R+poonceonces.litmus
87	As above, but without the smp_mb() invocations.
88
89SB+mbonceonces.litmus
90	This is the fully ordered (again, via smp_mb() version of store
91	buffering, which forms the core of Dekker's mutual-exclusion
92	algorithm.
93
94SB+poonceonces.litmus
95	As above, but without the smp_mb() invocations.
96
97S+poonceonces.litmus
98	As below, but without the smp_wmb() and acquire load.
99
100S+wmbonceonce+poacquireonce.litmus
101	Can a smp_wmb(), instead of a release, and an acquire order
102	a prior store against a subsequent store?
103
104WRC+poonceonces+Once.litmus
105WRC+pooncerelease+rmbonceonce+Once.litmus
106	These two are members of an extension of the MP litmus-test class
107	in which the first write is moved to a separate process.
108
109Z6.0+pooncelock+pooncelock+pombonce.litmus
110	Is the ordering provided by a spin_unlock() and a subsequent
111	spin_lock() sufficient to make ordering apparent to accesses
112	by a process not holding the lock?
113
114Z6.0+pooncelock+poonceLock+pombonce.litmus
115	As above, but with smp_mb__after_spinlock() immediately
116	following the spin_lock().
117
118Z6.0+pooncerelease+poacquirerelease+mbonceonce.litmus
119	Is the ordering provided by a release-acquire chain sufficient
120	to make ordering apparent to accesses by a process that does
121	not participate in that release-acquire chain?
122
123A great many more litmus tests are available here:
124
125	https://github.com/paulmckrcu/litmus
126