[PATCH v5 06/12] cpuset: use partition_update() for remote partition update

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

From: Ridong Chen <chenridong@xiaomi.com>

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: Ridong Chen <chenridong@xiaomi.com>
---
 kernel/cgroup/cpuset.c | 28 ++++++----------------------
 1 file changed, 6 insertions(+), 22 deletions(-)

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 681adcde10e8..7a3e797aee52 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1835,8 +1835,8 @@ static void partition_disable(struct cpuset *cs, int new_prs,
  * will be added to the subpartitions_cpus and removed from parent's
  * effective_cpus, and the tmp->delmask vice versa.
  */
-static void __maybe_unused partition_update(struct cpuset *cs, int prs, struct cpumask *xcpus,
-					    struct cpumask *excpus, struct tmpmasks *tmp)
+static void partition_update(struct cpuset *cs, int prs, struct cpumask *xcpus,
+			     struct cpumask *excpus, struct tmpmasks *tmp)
 {
 	struct cpuset *parent;
 
@@ -1935,7 +1935,6 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs,
 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;
 
 	if (WARN_ON_ONCE(!is_remote_partition(cs)))
@@ -1948,15 +1947,15 @@ 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))
 			WRITE_ONCE(cs->prs_err, PERR_ACCESS);
@@ -1971,22 +1970,7 @@ static void remote_cpus_update(struct cpuset *cs, struct cpumask *xcpus,
 	}
 
 	cs->remote_partition_updating = true;
-	spin_lock_irq(&callback_lock);
-	if (adding)
-		partition_xcpus_add(prs, NULL, tmp->addmask);
-	if (deleting)
-		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);
-	if (adding || deleting)
-		cpuset_force_rebuild();
-
+	partition_update(cs, prs, xcpus, excpus, tmp);
 	/*
 	 * Propagate changes in top_cpuset's effective_cpus down the hierarchy.
 	 */
-- 
2.34.1