From: Chen Ridong <chenridong@huawei.com>
The partition_disable() function introduced earlier can be extended to
handle local partition disablement.
First, partition_disable() was enhanced to support local partitions by
properly managing the parent's nr_subparts counter and integrating
notification operations.
Then, local_partition_disable() is introduced, which extracts the local
partition disable logic from update_parent_effective_cpumask(). It calls
partition_disable() to complete the disablement process.
This refactoring establishes a clear separation between local and remote
partition operations while promoting code reuse through the shared
partition_disable() infrastructure.
Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
kernel/cgroup/cpuset.c | 60 ++++++++++++++++++++++++++++++------------
1 file changed, 43 insertions(+), 17 deletions(-)
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 154992cdfe9a..87ba43e93540 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1576,13 +1576,20 @@ static void partition_disable(struct cpuset *cs, struct cpuset *parent,
int new_prs, enum prs_errcode prs_err)
{
bool isolcpus_updated;
+ int old_prs;
lockdep_assert_held(&cpuset_mutex);
WARN_ON_ONCE(new_prs > 0);
WARN_ON_ONCE(!cpuset_v2());
+ old_prs = cs->partition_root_state;
spin_lock_irq(&callback_lock);
list_del_init(&cs->remote_sibling);
+ if (parent && is_partition_valid(parent) &&
+ is_partition_valid(cs)) {
+ parent->nr_subparts -= 1;
+ WARN_ON_ONCE(parent->nr_subparts < 0);
+ }
/* disable a partition should only delete exclusive cpus */
isolcpus_updated = partition_xcpus_del(cs->partition_root_state,
parent, cs->effective_xcpus);
@@ -1592,6 +1599,9 @@ static void partition_disable(struct cpuset *cs, struct cpuset *parent,
spin_unlock_irq(&callback_lock);
update_unbound_workqueue_cpumask(isolcpus_updated);
cpuset_force_rebuild();
+ /* Clear exclusive flag; no errors are expected */
+ update_partition_exclusive_flag(cs, new_prs);
+ notify_partition_change(cs, old_prs);
}
/**
@@ -1870,6 +1880,37 @@ static int local_partition_enable(struct cpuset *cs,
return 0;
}
+/**
+ * local_partition_disable - Disable a local partition
+ * @cs: Target cpuset (local partition root) to disable
+ * @tmp: Temporary masks for CPU calculations
+ */
+static void local_partition_disable(struct cpuset *cs, struct tmpmasks *tmp)
+{
+ struct cpuset *parent = parent_cs(cs);
+ bool cpumask_updated = false;
+
+ lockdep_assert_held(&cpuset_mutex);
+ WARN_ON_ONCE(is_remote_partition(cs)); /* For local partition only */
+
+ if (!is_partition_valid(cs))
+ return;
+
+ /*
+ * May need to add cpus back to parent's effective_cpus
+ * (and maybe removed from subpartitions_cpus/isolated_cpus)
+ * for valid partition root. xcpus may contain CPUs that
+ * shouldn't be removed from the two global cpumasks.
+ */
+ cpumask_updated = !cpumask_empty(cs->effective_xcpus);
+ partition_disable(cs, parent, PRS_MEMBER, PERR_NONE);
+
+ if (cpumask_updated) {
+ cpuset_update_tasks_cpumask(parent, tmp->addmask);
+ update_sibling_cpumasks(parent, cs, tmp);
+ }
+}
+
/**
* update_parent_effective_cpumask - update effective_cpus mask of parent cpuset
* @cs: The cpuset that requests change in partition root state
@@ -1962,20 +2003,7 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd,
nocpu = tasks_nocpu_error(parent, cs, xcpus);
- if (cmd == partcmd_disable) {
- /*
- * May need to add cpus back to parent's effective_cpus
- * (and maybe removed from subpartitions_cpus/isolated_cpus)
- * for valid partition root. xcpus may contain CPUs that
- * shouldn't be removed from the two global cpumasks.
- */
- if (is_partition_valid(cs)) {
- cpumask_copy(tmp->addmask, cs->effective_xcpus);
- adding = true;
- subparts_delta--;
- }
- new_prs = PRS_MEMBER;
- } else if (newmask) {
+ if (newmask) {
/*
* Empty cpumask is not allowed
*/
@@ -3104,9 +3132,7 @@ static int update_prstate(struct cpuset *cs, int new_prs)
if (is_remote_partition(cs))
remote_partition_disable(cs, &tmpmask);
else
- update_parent_effective_cpumask(cs, partcmd_disable,
- NULL, &tmpmask);
-
+ local_partition_disable(cs, &tmpmask);
/*
* Invalidation of child partitions will be done in
* update_cpumasks_hier().
--
2.34.1