From 72c5ae18ebe6588101f2c1e96be61618ce06f182 Mon Sep 17 00:00:00 2001 From: Liang Luo Date: Thu, 20 Aug 2026 10:37:44 +0800 Subject: [PATCH] Docs/admin-guide/cgroup-v2: document BPF scheduler callbacks for cpu.max and cpu.idle The cpu.weight and cpu.weight.nice entries already state that the files also affect a BPF scheduler through the cgroup_set_weight callback. However, cpu.max, cpu.max.burst and cpu.idle only mention the fair-class scheduler, even though sched_ext implements the cgroup_set_bandwidth (notified with the period/quota from cpu.max and the burst from cpu.max.burst) and cgroup_set_idle callbacks from these interfaces. Mirror the cpu.weight wording for the three entries and generalize the category preamble to refer to the corresponding cgroup_set_* callback so it keeps covering the entries below. Suggested-by: Tejun Heo Signed-off-by: Liang Luo Signed-off-by: Tejun Heo --- Documentation/admin-guide/cgroup-v2.rst | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index aed195a71cbf..3dc6889ebdb2 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1130,9 +1130,9 @@ policy and the underlying scheduler. From the point of view of the cpu controlle processes can be categorized as follows: * Processes under the fair-class scheduler -* Processes under a BPF scheduler with the ``cgroup_set_weight`` callback +* Processes under a BPF scheduler with the corresponding ``cgroup_set_*`` callback * Everything else: ``SCHED_{FIFO,RR,DEADLINE}`` and processes under a BPF scheduler - without the ``cgroup_set_weight`` callback + without the corresponding ``cgroup_set_*`` callback For details on when a process is under the fair-class scheduler or a BPF scheduler, check out :ref:`Documentation/scheduler/sched-ext.rst `. @@ -1202,7 +1202,9 @@ will be referred to. All time durations are in microseconds. $PERIOD duration. "max" for $MAX indicates no limit. If only one number is written, $MAX is updated. - This file affects only processes under the fair-class scheduler. + This file affects only processes under the fair-class scheduler and a BPF + scheduler with the ``cgroup_set_bandwidth`` callback depending on what + the callback actually does. cpu.max.burst A read-write single value file which exists on non-root @@ -1210,7 +1212,9 @@ will be referred to. All time durations are in microseconds. The burst in the range [0, $MAX]. - This file affects only processes under the fair-class scheduler. + This file affects only processes under the fair-class scheduler and a BPF + scheduler with the ``cgroup_set_bandwidth`` callback depending on what + the callback actually does. cpu.pressure A read-write nested-keyed file. @@ -1262,7 +1266,9 @@ will be referred to. All time durations are in microseconds. own relative priorities, but the cgroup itself will be treated as very low priority relative to its peers. - This file affects only processes under the fair-class scheduler. + This file affects only processes under the fair-class scheduler and a BPF + scheduler with the ``cgroup_set_idle`` callback depending on what the + callback actually does. Memory ------