[PATCH RFC v2 09/22] cpuset: use partition_update() for remote partition update

From: Chen Ridong
Date: Sat Oct 25 2025 - 03:05:05 EST


From: Chen Ridong <chenridong@xxxxxxxxxx>

Now that the partition_update() helper is available, use it to replace
the existing remote partition update logic. This unifies the update
path through a single centralized function.

Signed-off-by: Chen Ridong <chenridong@xxxxxxxxxx>
---
kernel/cgroup/cpuset.c | 28 ++++------------------------
1 file changed, 4 insertions(+), 24 deletions(-)

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 7577e9134094..5b57c5370641 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1781,10 +1781,6 @@ static void remote_partition_disable(struct cpuset *cs, struct tmpmasks *tmp)
static void remote_cpus_update(struct cpuset *cs, struct cpumask *xcpus,
struct cpumask *excpus, struct tmpmasks *tmp)
{
- bool adding, deleting;
- int prs = cs->partition_root_state;
- int isolcpus_updated = 0;
-
if (WARN_ON_ONCE(!is_remote_partition(cs)))
return;

@@ -1795,15 +1791,15 @@ static void remote_cpus_update(struct cpuset *cs, struct cpumask *xcpus,
goto invalidate;
}

- adding = cpumask_andnot(tmp->addmask, excpus, cs->effective_xcpus);
- deleting = cpumask_andnot(tmp->delmask, cs->effective_xcpus, excpus);
+ cpumask_andnot(tmp->addmask, excpus, cs->effective_xcpus);
+ cpumask_andnot(tmp->delmask, cs->effective_xcpus, excpus);

/*
* Additions of remote CPUs is only allowed if those CPUs are
* not allocated to other partitions and there are effective_cpus
* left in the top cpuset.
*/
- if (adding) {
+ if (!cpumask_empty(tmp->addmask)) {
WARN_ON_ONCE(cpumask_intersects(tmp->addmask, subpartitions_cpus));
if (!capable(CAP_SYS_ADMIN))
cs->prs_err = PERR_ACCESS;
@@ -1814,23 +1810,7 @@ static void remote_cpus_update(struct cpuset *cs, struct cpumask *xcpus,
goto invalidate;
}

- spin_lock_irq(&callback_lock);
- if (adding)
- isolcpus_updated += partition_xcpus_add(prs, NULL, tmp->addmask);
- if (deleting)
- isolcpus_updated += partition_xcpus_del(prs, NULL, tmp->delmask);
- /*
- * Need to update effective_xcpus and exclusive_cpus now as
- * update_sibling_cpumasks() below may iterate back to the same cs.
- */
- cpumask_copy(cs->effective_xcpus, excpus);
- if (xcpus)
- cpumask_copy(cs->exclusive_cpus, xcpus);
- spin_unlock_irq(&callback_lock);
- update_unbound_workqueue_cpumask(isolcpus_updated);
- if (adding || deleting)
- cpuset_force_rebuild();
-
+ partition_update(cs, cs->partition_root_state, xcpus, excpus, tmp);
/*
* Propagate changes in top_cpuset's effective_cpus down the hierarchy.
*/
--
2.34.1