Document the new cpuset.cpus.isolation_full control file. Currently only the rcu_nocbs flag is supported, but more will be added in the future. Signed-off-by: Waiman Long <longman@xxxxxxxxxx> --- Documentation/admin-guide/cgroup-v2.rst | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 17e6e9565156..bbd066838f93 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -2352,6 +2352,30 @@ Cpuset Interface Files isolated partitions. It will be empty if no isolated partition is created. + cpuset.cpus.isolation_full + A read multiple values and write single value file which exists + on root cgroup only. + + This file shows the state of full CPU isolation mode for isolated + CPUs in isolated partitions. It shows either "0' if full CPU + isolation mode is disabled, or "1" followed by a comma-separated + list of additional CPU isolation flags that are enabled. + The currently supported CPU isolation flag is: + + rcu_nocbs + RCU no-callback CPU mode, which prevents such CPUs' + callbacks from being invoked in softirq context. + Invocation of such CPUs' RCU callbacks will instead be + offloaded to "rcuox/N" kthreads created for that purpose. + It is similar in functionality to the "rcu_nocbs" + boot command line option, but for dynamically created + isolated CPUs in isolated partitions. This flag can + only be enabled if such a "rcu_nocbs" option is present + in the boot command line of the running kernel. + + Full CPU isolation mode is enabled by writing a non-zero value + to this file and disabled by writing a zero value to it. + cpuset.cpus.partition A read-write single value file which exists on non-root cpuset-enabled cgroups. This flag is owned by the parent cgroup -- 2.39.3
