arm_mpam: resctrl: Implement helpers to update configuration

resctrl has two helpers for updating the configuration.
resctrl_arch_update_one() updates a single value, and is used by the
software-controller to apply feedback to the bandwidth controls, it has to
be called on one of the CPUs in the resctrl:domain.

resctrl_arch_update_domains() copies multiple staged configurations, it can
be called from anywhere.

Both helpers should update any changes to the underlying hardware.

Implement resctrl_arch_update_domains() to use
resctrl_arch_update_one(). Neither need to be called on a specific CPU as
the mpam driver will send IPIs as needed.

Tested-by: Gavin Shan <gshan@redhat.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Zeng Heng <zengheng4@huawei.com>
Tested-by: Punit Agrawal <punit.agrawal@oss.qualcomm.com>
Tested-by: Jesse Chick <jessechick@os.amperecomputing.com>
Reviewed-by: Zeng Heng <zengheng4@huawei.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Co-developed-by: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>

diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c
index 3af57b6f2c1b51738e66aa8af2acc04ddb08f663..ea60777934ffdfc9ceb7480a1e70c2c38331f08e 100644 (file)
--- a/drivers/resctrl/mpam_resctrl.c
+++ b/drivers/resctrl/mpam_resctrl.c
@@ -213,6 +213,76 @@ u32 resctrl_arch_get_config(struct rdt_resource *r, struct rdt_ctrl_domain *d,
        }
 }
 
+int resctrl_arch_update_one(struct rdt_resource *r, struct rdt_ctrl_domain *d,
+                           u32 closid, enum resctrl_conf_type t, u32 cfg_val)
+{
+       u32 partid;
+       struct mpam_config cfg;
+       struct mpam_props *cprops;
+       struct mpam_resctrl_res *res;
+       struct mpam_resctrl_dom *dom;
+
+       lockdep_assert_cpus_held();
+       lockdep_assert_irqs_enabled();
+
+       /*
+        * No need to check the CPU as mpam_apply_config() doesn't care, and
+        * resctrl_arch_update_domains() relies on this.
+        */
+       res = container_of(r, struct mpam_resctrl_res, resctrl_res);
+       dom = container_of(d, struct mpam_resctrl_dom, resctrl_ctrl_dom);
+       cprops = &res->class->props;
+
+       partid = resctrl_get_config_index(closid, t);
+       if (!r->alloc_capable || partid >= resctrl_arch_get_num_closid(r)) {
+               pr_debug("Not alloc capable or computed PARTID out of range\n");
+               return -EINVAL;
+       }
+
+       /*
+        * Copy the current config to avoid clearing other resources when the
+        * same component is exposed multiple times through resctrl.
+        */
+       cfg = dom->ctrl_comp->cfg[partid];
+
+       switch (r->rid) {
+       case RDT_RESOURCE_L2:
+       case RDT_RESOURCE_L3:
+               cfg.cpbm = cfg_val;
+               mpam_set_feature(mpam_feat_cpor_part, &cfg);
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       return mpam_apply_config(dom->ctrl_comp, partid, &cfg);
+}
+
+int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid)
+{
+       int err;
+       struct rdt_ctrl_domain *d;
+
+       lockdep_assert_cpus_held();
+       lockdep_assert_irqs_enabled();
+
+       list_for_each_entry_rcu(d, &r->ctrl_domains, hdr.list) {
+               for (enum resctrl_conf_type t = 0; t < CDP_NUM_TYPES; t++) {
+                       struct resctrl_staged_config *cfg = &d->staged_config[t];
+
+                       if (!cfg->have_new_ctrl)
+                               continue;
+
+                       err = resctrl_arch_update_one(r, d, closid, t,
+                                                     cfg->new_ctrl);
+                       if (err)
+                               return err;
+               }
+       }
+
+       return 0;
+}
+
 void resctrl_arch_reset_all_ctrls(struct rdt_resource *r)
 {
        struct mpam_resctrl_res *res;