[RFC PATCH 06/20] x86/intel_rdt: Add a helper to read a closid's configuration for show_doms()

[James Morse]

The configuration values used by the arch code may not be the same
as the bitmaps generated by resctrl, resctrl shouldn't read or
write them directly.

update_domains() and the staged config are suitable for letting the
arch code perform any conversion. Add a helper to read the current
configuration.

This will allow another architecture to scale the bitmaps if
necessary, and possibly use controls that don't take a bitmap at all.

Signed-off-by: James Morse <james.mo...@arm.com>
---
 arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c | 17 +++++++++++++----
 arch/x86/kernel/cpu/intel_rdt_monitor.c     |  2 +-
 include/linux/resctrl.h                     |  3 +++
 3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c 
b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
index 01ffd455313a..ec3c15ee3473 100644
--- a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
+++ b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
@@ -322,21 +322,30 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file 
*of,
        return ret ?: nbytes;
 }
 
+void resctrl_arch_get_config(struct rdt_resource *r, struct rdt_domain *d,
+                                   u32 closid, u32 *value)
+{
+       struct rdt_hw_domain *hw_dom = rc_dom_to_rdt(d);
+
+       if (!is_mba_sc(r))
+               *value = hw_dom->ctrl_val[closid];
+       else
+               *value = hw_dom->mbps_val[closid];
+}
+
 static void show_doms(struct seq_file *s, struct rdt_resource *r, int closid)
 {
-       struct rdt_hw_domain *hw_dom;
+
        struct rdt_domain *dom;
        bool sep = false;
        u32 ctrl_val;
 
        seq_printf(s, "%*s:", max_name_width, r->name);
        list_for_each_entry(dom, &r->domains, list) {
-               hw_dom = rc_dom_to_rdt(dom);
                if (sep)
                        seq_puts(s, ";");
 
-               ctrl_val = (!is_mba_sc(r) ? hw_dom->ctrl_val[closid] :
-                           hw_dom->mbps_val[closid]);
+               resctrl_arch_get_config(r, dom, closid, &ctrl_val);
                seq_printf(s, r->format_str, dom->id, max_data_width,
                           ctrl_val);
                sep = true;
diff --git a/arch/x86/kernel/cpu/intel_rdt_monitor.c 
b/arch/x86/kernel/cpu/intel_rdt_monitor.c
index c05f1cecf6cd..42ddcefc7065 100644
--- a/arch/x86/kernel/cpu/intel_rdt_monitor.c
+++ b/arch/x86/kernel/cpu/intel_rdt_monitor.c
@@ -390,7 +390,7 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct 
rdt_domain *dom_mbm)
        hw_dom_mba = rc_dom_to_rdt(dom_mba);
 
        cur_bw = pmbm_data->prev_bw;
-       user_bw = hw_dom_mba->mbps_val[closid];
+       resctrl_arch_get_config(r_mba, dom_mba, closid, &user_bw);
        delta_bw = pmbm_data->delta_bw;
        cur_msr_val = hw_dom_mba->ctrl_val[closid];
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 370db085ee77..03d9fbc230af 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -125,4 +125,7 @@ struct rdt_resource {
 
 };
 
+void resctrl_arch_get_config(struct rdt_resource *r, struct rdt_domain *d,
+                            u32 closid, u32 *value);
+
 #endif /* __LINUX_RESCTRL_H */
-- 
2.18.0