+ kernel-refactor-shorten-has_pending_signals.patch added to mm-nonmm-unstable branch

+ kernel-refactor-shorten-has_pending_signals.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: kernel: refactor: shorten has_pending_signals
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     kernel-refactor-shorten-has_pending_signals.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kernel-refactor-shorten-has_pending_signals.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Andrea Calabrese <andrea.calabrese@amarulasolutions.com>
Subject: kernel: refactor: shorten has_pending_signals
Date: Wed, 20 May 2026 08:28:50 +0200

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 <andrea.calabrese@amarulasolutions.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Adrian Huang <adrianhuang0701@gmail.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/signal.c |   26 ++++----------------------
 1 file changed, 4 insertions(+), 22 deletions(-)

--- a/kernel/signal.c~kernel-refactor-shorten-has_pending_signals
+++ a/kernel/signal.c
@@ -130,28 +130,10 @@ static bool sig_ignored(struct task_stru
  */
 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))
_

Patches currently in -mm which might be from andrea.calabrese@amarulasolutions.com are

kernel-refactor-shorten-has_pending_signals.patch