xref: /OK3568_Linux_fs/kernel/scripts/coccinelle/locks/double_lock.cocci (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun// SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun/// Find double locks.  False positives may occur when some paths cannot
3*4882a593Smuzhiyun/// occur at execution, due to the values of variables, and when there is
4*4882a593Smuzhiyun/// an intervening function call that releases the lock.
5*4882a593Smuzhiyun///
6*4882a593Smuzhiyun// Confidence: Moderate
7*4882a593Smuzhiyun// Copyright: (C) 2010 Nicolas Palix, DIKU.
8*4882a593Smuzhiyun// Copyright: (C) 2010 Julia Lawall, DIKU.
9*4882a593Smuzhiyun// Copyright: (C) 2010 Gilles Muller, INRIA/LiP6.
10*4882a593Smuzhiyun// URL: http://coccinelle.lip6.fr/
11*4882a593Smuzhiyun// Comments:
12*4882a593Smuzhiyun// Options: --no-includes --include-headers
13*4882a593Smuzhiyun
14*4882a593Smuzhiyunvirtual org
15*4882a593Smuzhiyunvirtual report
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun@locked@
18*4882a593Smuzhiyunposition p1;
19*4882a593Smuzhiyunexpression E1;
20*4882a593Smuzhiyunposition p;
21*4882a593Smuzhiyun@@
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun(
24*4882a593Smuzhiyunmutex_lock@p1
25*4882a593Smuzhiyun|
26*4882a593Smuzhiyunmutex_trylock@p1
27*4882a593Smuzhiyun|
28*4882a593Smuzhiyunspin_lock@p1
29*4882a593Smuzhiyun|
30*4882a593Smuzhiyunspin_trylock@p1
31*4882a593Smuzhiyun|
32*4882a593Smuzhiyunread_lock@p1
33*4882a593Smuzhiyun|
34*4882a593Smuzhiyunread_trylock@p1
35*4882a593Smuzhiyun|
36*4882a593Smuzhiyunwrite_lock@p1
37*4882a593Smuzhiyun|
38*4882a593Smuzhiyunwrite_trylock@p1
39*4882a593Smuzhiyun) (E1@p,...);
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun@balanced@
42*4882a593Smuzhiyunposition p1 != locked.p1;
43*4882a593Smuzhiyunposition locked.p;
44*4882a593Smuzhiyunidentifier lock,unlock;
45*4882a593Smuzhiyunexpression x <= locked.E1;
46*4882a593Smuzhiyunexpression E,locked.E1;
47*4882a593Smuzhiyunexpression E2;
48*4882a593Smuzhiyun@@
49*4882a593Smuzhiyun
50*4882a593Smuzhiyunif (E) {
51*4882a593Smuzhiyun <+... when != E1
52*4882a593Smuzhiyun lock(E1@p,...)
53*4882a593Smuzhiyun ...+>
54*4882a593Smuzhiyun}
55*4882a593Smuzhiyun... when != E1
56*4882a593Smuzhiyun    when != \(x = E2\|&x\)
57*4882a593Smuzhiyun    when forall
58*4882a593Smuzhiyunif (E) {
59*4882a593Smuzhiyun <+... when != E1
60*4882a593Smuzhiyun unlock@p1(E1,...)
61*4882a593Smuzhiyun ...+>
62*4882a593Smuzhiyun}
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun@r depends on !balanced exists@
65*4882a593Smuzhiyunexpression x <= locked.E1;
66*4882a593Smuzhiyunexpression locked.E1;
67*4882a593Smuzhiyunexpression E2;
68*4882a593Smuzhiyunidentifier lock;
69*4882a593Smuzhiyunposition locked.p,p1,p2;
70*4882a593Smuzhiyun@@
71*4882a593Smuzhiyun
72*4882a593Smuzhiyunlock@p1 (E1@p,...);
73*4882a593Smuzhiyun... when != E1
74*4882a593Smuzhiyun    when != \(x = E2\|&x\)
75*4882a593Smuzhiyunlock@p2 (E1,...);
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun@script:python depends on org@
78*4882a593Smuzhiyunp1 << r.p1;
79*4882a593Smuzhiyunp2 << r.p2;
80*4882a593Smuzhiyunlock << r.lock;
81*4882a593Smuzhiyun@@
82*4882a593Smuzhiyun
83*4882a593Smuzhiyuncocci.print_main(lock,p1)
84*4882a593Smuzhiyuncocci.print_secs("second lock",p2)
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun@script:python depends on report@
87*4882a593Smuzhiyunp1 << r.p1;
88*4882a593Smuzhiyunp2 << r.p2;
89*4882a593Smuzhiyunlock << r.lock;
90*4882a593Smuzhiyun@@
91*4882a593Smuzhiyun
92*4882a593Smuzhiyunmsg = "second lock on line %s" % (p2[0].line)
93*4882a593Smuzhiyuncoccilib.report.print_report(p1[0],msg)
94