rdt_find_domain() finds a domain given a resource and a cache-id.
It's not quite right for the resctrl arch API as it also returns the
position to insert a new domain, which is needed when bringing a
domain online in the arch code.

Wrap rdt_find_domain() in another function resctrl_arch_find_domain()
in order to avoid the unnecessary argument outside the arch code.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
---
Changes since v1:
 * [Commit message only] Minor rewording to avoid "impersonating code".

 * [Commit message only] Typo fix:
   s/in a another/in another/ in commit message.
---
 arch/x86/kernel/cpu/resctrl/core.c        | 9 +++++++--
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 2 +-
 arch/x86/kernel/cpu/resctrl/internal.h    | 2 --
 include/linux/resctrl.h                   | 2 ++
 4 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index fe7b99e7f07e..9ad660b2b097 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -381,8 +381,8 @@ void rdt_ctrl_update(void *arg)
  * caller, return the first domain whose id is bigger than the input id.
  * The domain list is sorted by id in ascending order.
  */
-struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
-				   struct list_head **pos)
+static struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
+					  struct list_head **pos)
 {
 	struct rdt_domain *d;
 	struct list_head *l;
@@ -406,6 +406,11 @@ struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
 	return NULL;
 }
 
+struct rdt_domain *resctrl_arch_find_domain(struct rdt_resource *r, int id)
+{
+	return rdt_find_domain(r, id, NULL);
+}
+
 static void setup_default_ctrlval(struct rdt_resource *r, u32 *dc)
 {
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 2ef91e748325..2100560dda6a 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -600,7 +600,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg)
 	evtid = md.u.evtid;
 
 	r = resctrl_arch_get_resource(resid);
-	d = rdt_find_domain(r, domid, NULL);
+	d = resctrl_arch_find_domain(r, domid);
 	if (IS_ERR_OR_NULL(d)) {
 		ret = -ENOENT;
 		goto out;
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 73b44b684c52..54aba0b6b7d2 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -535,8 +535,6 @@ void rdtgroup_kn_unlock(struct kernfs_node *kn);
 int rdtgroup_kn_mode_restrict(struct rdtgroup *r, const char *name);
 int rdtgroup_kn_mode_restore(struct rdtgroup *r, const char *name,
 			     umode_t mask);
-struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
-				   struct list_head **pos);
 ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
 				char *buf, size_t nbytes, loff_t off);
 int rdtgroup_schemata_show(struct kernfs_open_file *of,
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 476d92ab0884..5f1d578371ab 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -277,6 +277,8 @@ static inline u32 resctrl_get_default_ctrl(struct rdt_resource *r)
 
 /* The number of closid supported by this resource regardless of CDP */
 u32 resctrl_arch_get_num_closid(struct rdt_resource *r);
+
+struct rdt_domain *resctrl_arch_find_domain(struct rdt_resource *r, int id);
 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
 /*
-- 
2.39.2