From: Tao Cui <[email protected]> Document the named-model binding of io.cost.model in the io.cost.model section of the cgroup v2 documentation: the binding and restore syntax, the unknown-name rejection, the full-replacement semantics of a bound model and the unregister lifetime.
Signed-off-by: Tao Cui <[email protected]> --- Documentation/admin-guide/cgroup-v2.rst | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 8d2603751c51a..0d2d0525255cb 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -2124,6 +2124,18 @@ IO Interface Files parameters are written to, "ctrl" become "user" and the automatic changes are disabled. + When CONFIG_BLK_CGROUP_IOCOST_BPF is enabled, "model" also accepts + the name of a registered iocost_model_ops BPF struct_ops model: + "model=<name>" binds the model to the device and the model fully + replaces the builtin linear pricing, for every operation including + flushes; "model=linear" (or "ctrl=auto/user") restores the builtin + model. Writing an unknown name fails with ENOENT and nothing is + applied. Unregistering a model removes its name so it can no + longer be selected; devices already bound keep using it, and keep + receiving cgroup lifecycle notifications, until switched back to + the builtin model. See + include/linux/blk-iocost.h for the model interface. + When "model" is "linear", the following model parameters are defined. -- 2.43.0
