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

From: James Morse
Date: Fri Aug 24 2018 - 06:46:16 EST


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.morse@xxxxxxx>
---
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