[PATCH v5 12/40] x86/resctrl: Wrap resctrl_arch_find_domain() around rdt_find_domain()

James Morse posted 40 patches 1 month, 3 weeks ago
[PATCH v5 12/40] x86/resctrl: Wrap resctrl_arch_find_domain() around rdt_find_domain()
Posted by James Morse 1 month, 3 weeks ago
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: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
---
Changes since v3:
 * Used domain_list as a meaningful name instead of 'h'.

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        | 10 ++++++++--
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  2 +-
 arch/x86/kernel/cpu/resctrl/internal.h    |  2 --
 include/linux/resctrl.h                   |  3 +++
 4 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 7aecade1337c..fceb56697a4a 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -402,8 +402,8 @@ void rdt_ctrl_update(void *arg)
  * found (and NULL returned) then the first domain with id bigger than
  * the input id can be returned to the caller via @pos.
  */
-struct rdt_domain_hdr *rdt_find_domain(struct list_head *h, int id,
-				       struct list_head **pos)
+static struct rdt_domain_hdr *rdt_find_domain(struct list_head *h, int id,
+					      struct list_head **pos)
 {
 	struct rdt_domain_hdr *d;
 	struct list_head *l;
@@ -424,6 +424,12 @@ struct rdt_domain_hdr *rdt_find_domain(struct list_head *h, int id,
 	return NULL;
 }
 
+struct rdt_domain_hdr *resctrl_arch_find_domain(struct list_head *domain_list,
+						int id)
+{
+	return rdt_find_domain(domain_list, 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 56c41bfd07e4..7ea362c099db 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -620,7 +620,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg)
 		 * This file provides data from a single domain. Search
 		 * the resource to find the domain with "domid".
 		 */
-		hdr = rdt_find_domain(&r->mon_domains, domid, NULL);
+		hdr = resctrl_arch_find_domain(&r->mon_domains, domid);
 		if (!hdr || WARN_ON_ONCE(hdr->type != RESCTRL_MON_DOMAIN)) {
 			ret = -ENOENT;
 			goto out;
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 2bf08bd920f0..89eb2604a16e 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -578,8 +578,6 @@ 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_hdr *rdt_find_domain(struct list_head *h, 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 3b0283fa7f80..7a39f271561c 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -309,6 +309,9 @@ 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);
 u32 resctrl_arch_system_num_rmid_idx(void);
+
+struct rdt_domain_hdr *resctrl_arch_find_domain(struct list_head *domain_list,
+						int id);
 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
 /*
-- 
2.39.2
Re: [PATCH v5 12/40] x86/resctrl: Wrap resctrl_arch_find_domain() around rdt_find_domain()
Posted by Reinette Chatre 1 month ago
Hi James,

On 10/4/24 11:03 AM, James Morse wrote:
> 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.

I do not understand the motivation for this split. There does not seem to be
anything arch specific about rdt_find_domain(). Why does this need to
be arch API? Why can resctrl and all archs not use rdt_find_domain()?
Will MPAM organize domains differently somehow?

Reinette