[PATCH 6/8] x86/intel_rdt/mba: Add info directory files for MBA

[Vikas Shivappa]

Add files in info directory for MBA.
The files in the info directory are as follows :
- num_closids: max number of closids for MBA which represents the max
class of service user can configure.
- min_bw: the minimum memory bandwidth(b/w) values in percentage.

OS maps the b/w percentage values to memory b/w throttle delay values
and configures them via MSR interface by writing to the QOS_MSRs. These
delay values can have a linear or nonlinear scale.

- bw_gran: The memory b/w granularity that can be configured.
For ex: If the granularity is 10% and min_bw is 10, valid bandwidth
values are 10,20,30...

Signed-off-by: Vikas Shivappa <vikas.shivappa@xxxxxxxxxxxxxxx>
---
 arch/x86/include/asm/intel_rdt.h         |  2 +
 arch/x86/kernel/cpu/intel_rdt.c          |  1 +
 arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 64 ++++++++++++++++++++++++++++++++
 3 files changed, 67 insertions(+)

diff --git a/arch/x86/include/asm/intel_rdt.h b/arch/x86/include/asm/intel_rdt.h
index 36abed2..24de64c 100644
--- a/arch/x86/include/asm/intel_rdt.h
+++ b/arch/x86/include/asm/intel_rdt.h
@@ -149,6 +149,8 @@ struct msr_param {
 };
 
 void rdt_get_cache_infofile(struct rdt_resource *r);
+void rdt_get_mba_infofile(struct rdt_resource *r);
+
 extern struct mutex rdtgroup_mutex;
 
 extern struct rdt_resource rdt_resources_all[];
diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
index 481ff32..353c476b4 100644
--- a/arch/x86/kernel/cpu/intel_rdt.c
+++ b/arch/x86/kernel/cpu/intel_rdt.c
@@ -176,6 +176,7 @@ static bool rdt_get_mem_config(struct rdt_resource *r)
 		if (rdt_get_mb_table(r))
 			return false;
 	}
+	rdt_get_mba_infofile(r);
 
 	r->capable = true;
 	r->enabled = true;
diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index 0a70e87..b445ee8 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -518,6 +518,36 @@ static int rdt_min_cbm_bits_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+static int rdt_min_bw_show(struct kernfs_open_file *of,
+			     struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	seq_printf(seq, "%d\n", r->min_bw);
+
+	return 0;
+}
+
+static int rdt_bw_gran_show(struct kernfs_open_file *of,
+			     struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	seq_printf(seq, "%d\n", r->bw_gran);
+
+	return 0;
+}
+
+static int rdt_delay_linear_show(struct kernfs_open_file *of,
+			     struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	seq_printf(seq, "%d\n", r->delay_linear);
+
+	return 0;
+}
+
 /* rdtgroup information files for one cache resource. */
 static struct rftype res_cache_info_files[] = {
 	{
@@ -540,6 +570,40 @@ static int rdt_min_cbm_bits_show(struct kernfs_open_file *of,
 	},
 };
 
+/* rdtgroup information files for MBE. */
+static struct rftype res_mbe_info_files[] = {
+	{
+		.name		= "num_closids",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_num_closids_show,
+	},
+	{
+		.name		= "min_bandwidth",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_min_bw_show,
+	},
+	{
+		.name		= "bandwidth_gran",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_bw_gran_show,
+	},
+	{
+		.name		= "delay_linear",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_delay_linear_show,
+	},
+};
+
+void rdt_get_mba_infofile(struct rdt_resource *r)
+{
+	r->info_files = &res_mbe_info_files[0];
+	r->infofiles_len = ARRAY_SIZE(res_mbe_info_files);
+}
+
 void rdt_get_cache_infofile(struct rdt_resource *r)
 {
 	r->info_files = &res_cache_info_files[0];
-- 
1.9.1