From b7a8d7589a632c7de115362bbec6d88b10f685f1 Mon Sep 17 00:00:00 2001 From: Andrea Calabrese Date: Wed, 20 May 2026 08:28:50 +0200 Subject: [PATCH] kernel: refactor: shorten has_pending_signals In has_pending_signals there was a switch/case used for optimizations. However, today's compilers perform loop unrolling efficiently, thus it is not needed anymore. Put i inside the for declaration so we do not risk its escape from the scope. Moreover, i starts now from 0 and counts up, as it is a more usual pattern. Link: https://lore.kernel.org/20260520062849.183621-2-andrea.calabrese@amarulasolutions.com Signed-off-by: Andrea Calabrese Acked-by: Oleg Nesterov Cc: Adrian Huang Cc: Christian Brauner Cc: Marco Elver Cc: Peter Zijlstra Signed-off-by: Andrew Morton --- kernel/signal.c | 26 ++++---------------------- 1 file changed, 4 insertions(+), 22 deletions(-) diff --git a/kernel/signal.c b/kernel/signal.c index 0f509ee4f42d..fdee0b012a11 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -130,28 +130,10 @@ static bool sig_ignored(struct task_struct *t, int sig, bool force) */ static inline bool has_pending_signals(sigset_t *signal, sigset_t *blocked) { - unsigned long ready; - long i; - - switch (_NSIG_WORDS) { - default: - for (i = _NSIG_WORDS, ready = 0; --i >= 0 ;) - ready |= signal->sig[i] &~ blocked->sig[i]; - break; - - case 4: ready = signal->sig[3] &~ blocked->sig[3]; - ready |= signal->sig[2] &~ blocked->sig[2]; - ready |= signal->sig[1] &~ blocked->sig[1]; - ready |= signal->sig[0] &~ blocked->sig[0]; - break; - - case 2: ready = signal->sig[1] &~ blocked->sig[1]; - ready |= signal->sig[0] &~ blocked->sig[0]; - break; - - case 1: ready = signal->sig[0] &~ blocked->sig[0]; - } - return ready != 0; + unsigned long ready = 0; + for (long i = 0; i < _NSIG_WORDS; i++) + ready |= signal->sig[i] & ~blocked->sig[i]; + return ready != 0; } #define PENDING(p,b) has_pending_signals(&(p)->signal, (b))