From a53cbd149844cbde80f6adfc7f4233b8f230f664 Mon Sep 17 00:00:00 2001 From: Sang-Heon Jeon Date: Mon, 27 Jul 2026 22:52:44 +0900 Subject: coccinelle: mini_lock: improve performance when searching loops The 'looped' rule collects the returns inside a for loop to prevent 'err' from reporting them. It searches every for loop in the file, and on files with large loop bodies the search explodes. For example, kernel/bpf/verifier.c runs for over 200 seconds, almost entirely in 'looped' according to --profile. Since the kernel .cocciconfig sets a 200 second timeout, coccicheck silently skips the file. To avoid this, collect the candidate returns first, so that 'looped' checks only those positions. 'err' then excludes what 'looped' found. Every return that 'err' can report is also a candidate, so the same returns are excluded as before and the output does not change. A report-mode run over every .c file in the tree produces identical output. So verifier.c now finishes well within the timeout, in a few seconds. Signed-off-by: Sang-Heon Jeon Signed-off-by: Julia Lawall --- scripts/coccinelle/locks/mini_lock.cocci | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/coccinelle/locks/mini_lock.cocci b/scripts/coccinelle/locks/mini_lock.cocci index 71065d8a5d54..c65241c895ff 100644 --- a/scripts/coccinelle/locks/mini_lock.cocci +++ b/scripts/coccinelle/locks/mini_lock.cocci @@ -53,11 +53,31 @@ spin_lock_irq@p1 spin_lock_irqsave@p1 ) (E1@p,...); -@looped@ +@err_candidate exists@ +expression E1; +position prelocked.p; +position up != prelocked.p1; +position rc; +identifier lock,unlock; +@@ + +lock(E1@p,...); +... when != E1 + when any +if (...) { + ... when != E1 + return@rc ...; +} +... when != E1 + when any +unlock@up(E1,...); + +@looped exists@ +position err_candidate.rc; position r; @@ -for(...;...;...) { <+... return@r ...; ...+> } +for(...;...;...) { <+... return@rc@r ...; ...+> } @err exists@ expression E1; -- cgit