Merge branch into tip/master: 'sched/core'

 # New commits in sched/core:
    04998aa54848 ("sched/eevdf: Delayed dequeue task can't preempt")
    19b7bdc3a155 ("sched/fair: Fix stale comments referring to removed CFS concepts")
    b2463ebf2674 ("sched/debug: Remove unused schedstats")
    b0bc1c75f304 ("sched/psi: skip irqtime accounting when no new irq time has elapsed")
    296744614dd0 ("sched/fair: Reflow sched_balance_rq()")
    f2267ad5777f ("sched/fair: Simplify balance_interval reset logic in sched_balance_rq()")
    cdd9e37ed46a ("sched/fair: Don't trigger active lb if src_rq->curr is not on_rq")
    0d1e7a2bab35 ("sched/eevdf: Speedup short slice task scheduling")
    7cd2ef17de5e ("sched/eevdf: Always update slice protection")
    ba0d3bf5f97b ("sched/eevdf: Cancel slice protection if short slice task is eligible")
    7ad0ec7890b3 ("sched/eevdf: Update slice protection even when resched is already set")
    49f87b4d0be8 ("sched/eevdf: Take into account current's lag when updating slice protection")
    8f97b627ff1c ("sched/fair: Set next buddy for preempt short")
    3cd1f657fae5 ("sched/fair: Remove unused arguments from set_preempt_buddy()")
    85570f10a4c6 ("sched/eevdf: Move to a single runqueue")
    fb1050ac8e40 ("sched/fair: Change the default cgroup_mode to concur")
    507f910a4e1f ("sched/fair: Add cgroup_mode: tasks")
    5c0b58bd1c9f ("sched/fair: Add cgroup_mode: concur")
    90ac22ffef48 ("sched/fair: Add cgroup_mode: max")
    80ad6d3338eb ("sched/fair: Add cgroup_mode: up")
    4161cb2d867b ("sched/fair: Add cgroup_mode switch")
    4f166adb5cb0 ("sched/fair: Fix overflow in update_tg_cfs_runnable()")
    fa02b2868420 ("sched/core: Fix inter-class wakeup_preempt()")

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 22 insertions, 0 deletions

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 45944b3e31ca..e42f81a61311 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -4129,6 +4129,28 @@ bool cpuset_cpus_allowed_fallback(struct task_struct *tsk)
 	return changed;
 }
 
+/*
+ * Returns the number of CPUs available for this cgroup.
+ *
+ * This only really works for cgroup-v2 where all the controllers are mounted
+ * in the same hierarchy. If not cgroup-v2 or no cpuset controller is
+ * configured it reverts to num_online_cpus().
+ */
+int cpuset_num_cpus(struct cgroup *cgrp)
+{
+	int nr = num_online_cpus();
+	struct cpuset *cs;
+
+	if (is_in_v2_mode()) {
+		guard(rcu)();
+		cs = css_cs(cgroup_e_css(cgrp, &cpuset_cgrp_subsys));
+		if (cs)
+			nr = cpumask_weight(cs->effective_cpus);
+	}
+
+	return nr;
+}
+
 void __init cpuset_init_current_mems_allowed(void)
 {
 	nodes_setall(current->mems_allowed);