[PATCH v5 04/12] cpuset: use partition_enable() for remote partition enablement

[Ridong Chen <ridong.chen@linux.dev>]

From: Ridong Chen <chenridong@xiaomi.com>

Now that the partition_enable() helper is available, replace the
existing implementation for remote partition enablement with this
centralized function to unify the enablement logic.

As partition_enable() also sends the partition change notification,
update_prstate() may notify again at its end. cgroup_file_notify()
rate-limits the notifications, and the one in update_prstate() will be
removed later.

Signed-off-by: Ridong Chen <chenridong@xiaomi.com>
---
 kernel/cgroup/cpuset.c | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index c66864faab32..3702e43e95ef 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1725,8 +1725,8 @@ static void partition_state_update(struct cpuset *cs, int new_prs,
  * Transitions a cpuset to a partition root, only for v2.
  * It also supports the transition between root and isolated partition.
  */
-static void __maybe_unused partition_enable(struct cpuset *cs, struct cpuset *parent,
-					    int new_prs, struct cpumask *new_excpus)
+static void partition_enable(struct cpuset *cs, struct cpuset *parent,
+			     int new_prs, struct cpumask *new_excpus)
 {
 	int old_prs = cs->partition_root_state;
 
@@ -1914,14 +1914,7 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs,
 	if (prstate_housekeeping_conflict(new_prs, PRS_ROOT, tmp->new_cpus, NULL))
 		return PERR_HKEEPING;
 
-	spin_lock_irq(&callback_lock);
-	partition_xcpus_add(new_prs, NULL, tmp->new_cpus);
-	cs->remote_partition = true;
-	cpumask_copy(cs->effective_xcpus, tmp->new_cpus);
-	spin_unlock_irq(&callback_lock);
-	cpuset_force_rebuild();
-	WRITE_ONCE(cs->prs_err, 0);
-
+	partition_enable(cs, NULL, new_prs, tmp->new_cpus);
 	/*
 	 * Propagate changes in top_cpuset's effective_cpus down the hierarchy.
 	 */
-- 
2.34.1