From 7abedcd2ab797d9e4ae739402250c2d8a88a95e7 Mon Sep 17 00:00:00 2001 From: Guopeng Zhang Date: Tue, 22 Sep 2026 17:20:33 +0800 Subject: [PATCH] docs: cgroup-v2: Describe boot-isolated CPUs in cpuset.cpus.isolated cpuset.cpus.isolated is documented as empty when no isolated partition exists. This is not true when CPUs are isolated at boot with isolcpus=domain. cpuset_init() adds those CPUs to the isolated mask, and isolcpus= uses domain isolation by default. They remain listed after a partition using them is released. Document the boot-isolated CPUs as well. Suggested-by: Ridong Chen Reviewed-by: Ridong Chen Signed-off-by: Guopeng Zhang Reviewed-by: Waiman Long Signed-off-by: Tejun Heo --- Documentation/admin-guide/cgroup-v2.rst | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 86a2a0099178..f47b26b3ed7f 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -2657,8 +2657,9 @@ Cpuset Interface Files A read-only and root cgroup only multiple values file. This file shows the set of all isolated CPUs used in existing - isolated partitions. It will be empty if no isolated partition - is created. + isolated partitions or isolated at boot time via the "domain" + flag of "isolcpus". The latter remain listed even after any + partition using them is released. cpuset.cpus.partition A read-write single value file which exists on non-root