linux-kernel - [PATCH] doc: Update residual 1Hz handling description

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Message-ID: <20260112163901.338596-1-marco.crivellari@suse.com>
Date: Mon, 12 Jan 2026 17:39:01 +0100
From: Marco Crivellari <marco.crivellari@...e.com>
To: linux-kernel@...r.kernel.org,
	linux-doc@...r.kernel.org
Cc: Jonathan Corbet <corbet@....net>,
	Frederic Weisbecker <frederic@...nel.org>,
	Michal Hocko <mhocko@...e.com>,
	Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
	Marco Crivellari <marco.crivellari@...e.com>
Subject: [PATCH] doc: Update residual 1Hz handling description

When a CPU is nohz there is a residual 1Hz that must be handled.
Accordingly to the documentation, this should be manually affined to
housekeeping.

This is no longer the case: the residual 1Hz is automatically offloaded
to workqueues already affined to housekeeping CPUs.

So change the documentation accordingly.

Signed-off-by: Marco Crivellari <marco.crivellari@...e.com>
---
 Documentation/admin-guide/kernel-parameters.txt | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 902ecd92a29f..414fb42786c7 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2368,15 +2368,8 @@
 			nohz
 			  Disable the tick when a single task runs.
 
-			  A residual 1Hz tick is offloaded to workqueues, which you
-			  need to affine to housekeeping through the global
-			  workqueue's affinity configured via the
-			  /sys/devices/virtual/workqueue/cpumask sysfs file, or
-			  by using the 'domain' flag described below.
-
-			  NOTE: by default the global workqueue runs on all CPUs,
-			  so to protect individual CPUs the 'cpumask' file has to
-			  be configured manually after bootup.
+			  A residual 1Hz tick is offloaded to workqueues, already
+			  affined to housekeeping CPUs.
 
 			domain
 			  Isolate from the general SMP balancing and scheduling
-- 
2.52.0