[PATCH v2 16/45] arm_mpam: resctrl: Sort the order of the domain lists

[Ben Horgan]

From: James Morse <james.morse at arm.com>

resctrl documents that the domains appear in numeric order in the schemata
file. This means a little more work is needed when bringing a domain
online.

Add the support for this, using resctrl_find_domain() to find the point to
insert in the list.

Signed-off-by: James Morse <james.morse at arm.com>
Signed-off-by: Ben Horgan <ben.horgan at arm.com>
---
 drivers/resctrl/mpam_resctrl.c | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c
index 4beeeded00ff..5481d9cc69d9 100644
--- a/drivers/resctrl/mpam_resctrl.c
+++ b/drivers/resctrl/mpam_resctrl.c
@@ -117,6 +117,21 @@ static bool mpam_resctrl_offline_domain_hdr(unsigned int cpu,
 	return false;
 }
 
+static void mpam_resctrl_domain_insert(struct list_head *list,
+				       struct rdt_domain_hdr *new)
+{
+	struct rdt_domain_hdr *err;
+	struct list_head *pos = NULL;
+
+	lockdep_assert_held(&domain_list_lock);
+
+	err = resctrl_find_domain(list, new->id, &pos);
+	if (WARN_ON_ONCE(err))
+		return;
+
+	list_add_tail_rcu(&new->list, pos);
+}
+
 static struct mpam_resctrl_dom *
 mpam_resctrl_alloc_domain(unsigned int cpu, struct mpam_resctrl_res *res)
 {
@@ -154,8 +169,7 @@ mpam_resctrl_alloc_domain(unsigned int cpu, struct mpam_resctrl_res *res)
 		ctrl_d = &dom->resctrl_ctrl_dom;
 		mpam_resctrl_domain_hdr_init(cpu, ctrl_comp, &ctrl_d->hdr);
 		ctrl_d->hdr.type = RESCTRL_CTRL_DOMAIN;
-		/* TODO: this list should be sorted */
-		list_add_tail_rcu(&ctrl_d->hdr.list, &r->ctrl_domains);
+		mpam_resctrl_domain_insert(&r->ctrl_domains, &ctrl_d->hdr);
 		err = resctrl_online_ctrl_domain(r, ctrl_d);
 		if (err) {
 			dom = ERR_PTR(err);
@@ -169,8 +183,7 @@ mpam_resctrl_alloc_domain(unsigned int cpu, struct mpam_resctrl_res *res)
 		mon_d = &dom->resctrl_mon_dom;
 		mpam_resctrl_domain_hdr_init(cpu, ctrl_comp, &mon_d->hdr);
 		mon_d->hdr.type = RESCTRL_MON_DOMAIN;
-		/* TODO: this list should be sorted */
-		list_add_tail_rcu(&mon_d->hdr.list, &r->mon_domains);
+		mpam_resctrl_domain_insert(&r->mon_domains, &mon_d->hdr);
 		err = resctrl_online_mon_domain(r, mon_d);
 		if (err) {
 			dom = ERR_PTR(err);
-- 
2.43.0