1 files changed, 19 insertions, 5 deletions

diff --git a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
index 23e1d5c249c6..116d57b248d3 100644
--- a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
+++ b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
@@ -53,7 +53,8 @@ static bool bw_validate(char *buf, unsigned long *data, struct rdt_resource *r)
                 return false;
         }
 
-        if (bw < r->membw.min_bw || bw > r->default_ctrl) {
+        if ((bw < r->membw.min_bw || bw > r->default_ctrl) &&
+            !is_mba_sc(r)) {
                 rdt_last_cmd_printf("MB value %ld out of range [%d,%d]\n", bw,
                                     r->membw.min_bw, r->default_ctrl);
                 return false;
@@ -179,6 +180,8 @@ static int update_domains(struct rdt_resource *r, int closid)
         struct msr_param msr_param;
         cpumask_var_t cpu_mask;
         struct rdt_domain *d;
+        bool mba_sc;
+        u32 *dc;
         int cpu;
 
         if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
@@ -188,13 +191,20 @@ static int update_domains(struct rdt_resource *r, int closid)
         msr_param.high = msr_param.low + 1;
         msr_param.res = r;
 
+        mba_sc = is_mba_sc(r);
         list_for_each_entry(d, &r->domains, list) {
-                if (d->have_new_ctrl && d->new_ctrl != d->ctrl_val[closid]) {
+                dc = !mba_sc ? d->ctrl_val : d->mbps_val;
+                if (d->have_new_ctrl && d->new_ctrl != dc[closid]) {
                         cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask);
-                        d->ctrl_val[closid] = d->new_ctrl;
+                        dc[closid] = d->new_ctrl;
                 }
         }
-        if (cpumask_empty(cpu_mask))
+
+        /*
+         * Avoid writing the control msr with control values when
+         * MBA software controller is enabled
+         */
+        if (cpumask_empty(cpu_mask) || mba_sc)
                 goto done;
         cpu = get_cpu();
         /* Update CBM on this cpu if it's in cpu_mask. */
@@ -282,13 +292,17 @@ static void show_doms(struct seq_file *s, struct rdt_resource *r, int closid)
 {
         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) {
                 if (sep)
                         seq_puts(s, ";");
+
+                ctrl_val = (!is_mba_sc(r) ? dom->ctrl_val[closid] :
+                            dom->mbps_val[closid]);
                 seq_printf(s, r->format_str, dom->id, max_data_width,
-                           dom->ctrl_val[closid]);
+                           ctrl_val);
                 sep = true;
         }
         seq_puts(s, "\n");