From 75ff0feaa2755ba8f064f2085a8afbf6139a5195 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Mon, 27 Apr 2026 17:07:39 +0200 Subject: Documentation/kernel-parameters: Remove "Deprecated" from isolcpus= The isolcpus= option has been marked as deprecated in 2017. Back then it was desired for the domain sub option to be configured dynamically at runtime instead using this boot command line which provides a static configuration. In the meantime this option was extended by other sub options which don't have runtime counterpart or it does not make sense to provide one. The deprecated part always referred to the default `domain' sub option but it was not obvious. Also the reasoning behind the deprecation is sort of dubious: There is nothing wrong with a static configuration if there is no desired to reconfigure. This is useful on systems which have one purpose and the CPU partition configuration is not changed for the entire lifetime. Remove the "Deprecated" note. Remove the part of the description which suggest to use cpuset.sched_load_balance and instead point to the documentation file which explains how to use cpusets to configure this at runtime. Signed-off-by: Sebastian Andrzej Siewior Acked-by: Waiman Long Acked-by: Steven Rostedt Signed-off-by: Jonathan Corbet Message-ID: <20260427150739.bwVmmkj2@linutronix.de> --- Documentation/admin-guide/kernel-parameters.txt | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'Documentation') diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 319dfea30133..b1e2e50d5c8d 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2751,7 +2751,6 @@ Kernel parameters Format: ,,, isolcpus= [KNL,SMP,ISOL] Isolate a given set of CPUs from disturbance. - [Deprecated - use cpusets instead] Format: [flag-list,] Specify one or more CPUs to isolate from disturbances @@ -2776,11 +2775,10 @@ Kernel parameters Isolate from the general SMP balancing and scheduling algorithms. Note that performing domain isolation this way is irreversible: it's not possible to bring back a CPU to - the domains once isolated through isolcpus. It's strongly - advised to use cpusets instead to disable scheduler load - balancing through the "cpuset.sched_load_balance" file. - It offers a much more flexible interface where CPUs can - move in and out of an isolated set anytime. + the domains once isolated through this boot time + configuration. Use cpusets for a dynamic configuration + which can be altered at runtime. For details see + Documentation/admin-guide/cpu-isolation.rst. You can move a process onto or off an "isolated" CPU via the CPU affinity syscalls or cpuset. -- cgit v1.2.3