The ABMC feature provides an option to the user to pin (or assign) the
RMID to the hardware counter and monitor the bandwidth for a longer
duration. There are only a limited number of hardware counters.
Provide the interface to display the number of ABMC counters supported.
Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
---
v2: Changed the field name to mbm_assignable_counters from abmc_counters.
---
Documentation/arch/x86/resctrl.rst | 4 ++++
arch/x86/kernel/cpu/resctrl/monitor.c | 4 ++++
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 17 +++++++++++++++++
3 files changed, 25 insertions(+)
diff --git a/Documentation/arch/x86/resctrl.rst b/Documentation/arch/x86/resctrl.rst
index ecc6c65bdaca..73eeb50fd0b5 100644
--- a/Documentation/arch/x86/resctrl.rst
+++ b/Documentation/arch/x86/resctrl.rst
@@ -264,6 +264,10 @@ with the following files:
# cat /sys/fs/resctrl/info/L3_MON/mbm_local_bytes_config
0=0x30;1=0x30;3=0x15;4=0x15
+"mbm_assignable_counters":
+ Available when ABMC feature is supported. The number of assignable bandwidth
+ monitoring counters available.
+
"max_threshold_occupancy":
Read/write file provides the largest value (in
bytes) at which a previously used LLC_occupancy
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index a6c336b6de61..fa492ea820f0 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -823,6 +823,10 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
resctrl_file_fflags_init("mbm_local_bytes_config",
RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
}
+
+ if (rdt_cpu_has(X86_FEATURE_ABMC))
+ resctrl_file_fflags_init("mbm_assignable_counters",
+ RFTYPE_MON_INFO);
}
l3_mon_evt_init(r);
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 3e233251e7ed..53be5cd1c28e 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -811,6 +811,17 @@ static int rdtgroup_rmid_show(struct kernfs_open_file *of,
return ret;
}
+static int rdtgroup_mbm_assignable_counters_show(struct kernfs_open_file *of,
+ struct seq_file *s, void *v)
+{
+ struct rdt_resource *r = of->kn->parent->priv;
+ struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+
+ seq_printf(s, "%d\n", hw_res->mbm_assignable_counters);
+
+ return 0;
+}
+
#ifdef CONFIG_PROC_CPU_RESCTRL
/*
@@ -1861,6 +1872,12 @@ static struct rftype res_common_files[] = {
.seq_show = mbm_local_bytes_config_show,
.write = mbm_local_bytes_config_write,
},
+ {
+ .name = "mbm_assignable_counters",
+ .mode = 0444,
+ .kf_ops = &rdtgroup_kf_single_ops,
+ .seq_show = rdtgroup_mbm_assignable_counters_show,
+ },
{
.name = "cpus",
.mode = 0644,
--
2.34.1
