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authorBreno Leitao <leitao@debian.org>2026-08-05 07:52:36 -0700
committerTejun Heo <tj@kernel.org>2026-08-10 11:47:20 -1000
commita5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656 (patch)
tree39f5b258386e1127d253d293194e9a2991bf3c34 /scripts/coccinelle/null/badzero.cocci
downloadlinux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.tar.gz
linux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.zip
workqueue: skip the node_nr_active update for non-unbound workqueuesgrafted
apply_wqattrs_commit() updates node_nr_active->max unconditionally. wq->node_nr_active[] is only allocated for unbound workqueues, so guard the call before per-cpu workqueues start using this path. No functional change: only unbound workqueues reach apply_wqattrs_*() today. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'scripts/coccinelle/null/badzero.cocci')
-rw-r--r--scripts/coccinelle/null/badzero.cocci239
1 files changed, 239 insertions, 0 deletions
diff --git a/scripts/coccinelle/null/badzero.cocci b/scripts/coccinelle/null/badzero.cocci
new file mode 100644
index 000000000..35d443825
--- /dev/null
+++ b/scripts/coccinelle/null/badzero.cocci
@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/// Compare pointer-typed values to NULL rather than 0
+///
+//# This makes an effort to choose between !x and x == NULL. !x is used
+//# if it has previously been used with the function used to initialize x.
+//# This relies on type information. More type information can be obtained
+//# using the option -all_includes and the option -I to specify an
+//# include path.
+//
+// Confidence: High
+// Copyright: (C) 2012 Julia Lawall, INRIA/LIP6.
+// Copyright: (C) 2012 Gilles Muller, INRIA/LiP6.
+// URL: https://coccinelle.gitlabpages.inria.fr/website
+// Requires: 1.0.0
+// Options:
+
+virtual patch
+virtual context
+virtual org
+virtual report
+
+@initialize:ocaml@
+@@
+let negtable = Hashtbl.create 101
+
+@depends on patch@
+expression *E;
+identifier f;
+@@
+
+(
+ (E = f(...)) ==
+- 0
++ NULL
+|
+ (E = f(...)) !=
+- 0
++ NULL
+|
+- 0
++ NULL
+ == (E = f(...))
+|
+- 0
++ NULL
+ != (E = f(...))
+)
+
+
+@t1 depends on !patch@
+expression *E;
+identifier f;
+position p;
+@@
+
+(
+ (E = f(...)) ==
+* 0@p
+|
+ (E = f(...)) !=
+* 0@p
+|
+* 0@p
+ == (E = f(...))
+|
+* 0@p
+ != (E = f(...))
+)
+
+@script:python depends on org@
+p << t1.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING comparing pointer to 0")
+
+@script:python depends on report@
+p << t1.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING comparing pointer to 0")
+
+// Tests of returned values
+
+@s@
+identifier f;
+expression E,E1;
+@@
+
+ E = f(...)
+ ... when != E = E1
+ !E
+
+@script:ocaml depends on s@
+f << s.f;
+@@
+
+try let _ = Hashtbl.find negtable f in ()
+with Not_found -> Hashtbl.add negtable f ()
+
+@ r disable is_zero,isnt_zero exists @
+expression *E;
+identifier f;
+@@
+
+E = f(...)
+...
+(E == 0
+|E != 0
+|0 == E
+|0 != E
+)
+
+@script:ocaml@
+f << r.f;
+@@
+
+try let _ = Hashtbl.find negtable f in ()
+with Not_found -> include_match false
+
+// This rule may lead to inconsistent path problems, if E is defined in two
+// places
+@ depends on patch disable is_zero,isnt_zero @
+expression *E;
+expression E1;
+identifier r.f;
+@@
+
+E = f(...)
+<...
+(
+- E == 0
++ !E
+|
+- E != 0
++ E
+|
+- 0 == E
++ !E
+|
+- 0 != E
++ E
+)
+...>
+?E = E1
+
+@t2 depends on !patch disable is_zero,isnt_zero @
+expression *E;
+expression E1;
+identifier r.f;
+position p1;
+position p2;
+@@
+
+E = f(...)
+<...
+(
+* E == 0@p1
+|
+* E != 0@p2
+|
+* 0@p1 == E
+|
+* 0@p1 != E
+)
+...>
+?E = E1
+
+@script:python depends on org@
+p << t2.p1;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING comparing pointer to 0, suggest !E")
+
+@script:python depends on org@
+p << t2.p2;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING comparing pointer to 0")
+
+@script:python depends on report@
+p << t2.p1;
+@@
+
+coccilib.report.print_report(p[0], "WARNING comparing pointer to 0, suggest !E")
+
+@script:python depends on report@
+p << t2.p2;
+@@
+
+coccilib.report.print_report(p[0], "WARNING comparing pointer to 0")
+
+@ depends on patch disable is_zero,isnt_zero @
+expression *E;
+@@
+
+(
+ E ==
+- 0
++ NULL
+|
+ E !=
+- 0
++ NULL
+|
+- 0
++ NULL
+ == E
+|
+- 0
++ NULL
+ != E
+)
+
+@ t3 depends on !patch disable is_zero,isnt_zero @
+expression *E;
+position p;
+@@
+
+(
+* E == 0@p
+|
+* E != 0@p
+|
+* 0@p == E
+|
+* 0@p != E
+)
+
+@script:python depends on org@
+p << t3.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING comparing pointer to 0")
+
+@script:python depends on report@
+p << t3.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING comparing pointer to 0")