[tip: x86/cache] x86/resctrl: Add interface to read mbm_local_bytes_config

From: tip-bot2 for Babu Moger
Date: Tue Jan 24 2023 - 04:26:45 EST


The following commit has been merged into the x86/cache branch of tip:

Commit-ID: 73afb2d3ce2d7e0f9eee14e3f2b53d2bbfefd9c8
Gitweb: https://git.kernel.org/tip/73afb2d3ce2d7e0f9eee14e3f2b53d2bbfefd9c8
Author: Babu Moger <babu.moger@xxxxxxx>
AuthorDate: Fri, 13 Jan 2023 09:20:36 -06:00
Committer: Borislav Petkov (AMD) <bp@xxxxxxxxx>
CommitterDate: Mon, 23 Jan 2023 17:40:27 +01:00

x86/resctrl: Add interface to read mbm_local_bytes_config

The event configuration can be viewed by the user by reading the configuration
file /sys/fs/resctrl/info/L3_MON/mbm_local_bytes_config. The event
configuration settings are domain specific and will affect all the CPUs in the
domain.

Following are the types of events supported:

==== ===========================================================
Bits Description
==== ===========================================================
6 Dirty Victims from the QOS domain to all types of memory
5 Reads to slow memory in the non-local NUMA domain
4 Reads to slow memory in the local NUMA domain
3 Non-temporal writes to non-local NUMA domain
2 Non-temporal writes to local NUMA domain
1 Reads to memory in the non-local NUMA domain
0 Reads to memory in the local NUMA domain
==== ===========================================================

By default, the mbm_local_bytes_config is set to 0x15 to count all the local
event types.

For example:

$cat /sys/fs/resctrl/info/L3_MON/mbm_local_bytes_config
0=0x15;1=0x15;2=0x15;3=0x15

In this case, the event mbm_local_bytes is configured with 0x15 on
domains 0 to 3.

Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Link: https://lore.kernel.org/r/20230113152039.770054-11-babu.moger@xxxxxxx
---
arch/x86/kernel/cpu/resctrl/monitor.c | 4 +++-
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 16 ++++++++++++++++
2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 0ff45e3..28c6500 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -805,8 +805,10 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
mbm_total_event.configurable = true;
mbm_config_rftype_init("mbm_total_bytes_config");
}
- if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL))
+ if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL)) {
mbm_local_event.configurable = true;
+ mbm_config_rftype_init("mbm_local_bytes_config");
+ }
}

l3_mon_evt_init(r);
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index cd4e668..ad3c701 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1507,6 +1507,16 @@ static int mbm_total_bytes_config_show(struct kernfs_open_file *of,
return 0;
}

+static int mbm_local_bytes_config_show(struct kernfs_open_file *of,
+ struct seq_file *seq, void *v)
+{
+ struct rdt_resource *r = of->kn->parent->priv;
+
+ mbm_config_show(seq, r, QOS_L3_MBM_LOCAL_EVENT_ID);
+
+ return 0;
+}
+
/* rdtgroup information files for one cache resource. */
static struct rftype res_common_files[] = {
{
@@ -1612,6 +1622,12 @@ static struct rftype res_common_files[] = {
.seq_show = mbm_total_bytes_config_show,
},
{
+ .name = "mbm_local_bytes_config",
+ .mode = 0444,
+ .kf_ops = &rdtgroup_kf_single_ops,
+ .seq_show = mbm_local_bytes_config_show,
+ },
+ {
.name = "cpus",
.mode = 0644,
.kf_ops = &rdtgroup_kf_single_ops,