[PATCH 3/3] x86/intel_rdt: Update schemata read to show data in tabular format

[Vikas Shivappa]

The schemata file would display data from different resources on all
domains. Its cumbersome to read since they are not tabular and
data/names could be of different widths.  Make the schemata file to
display data in a tabular format thereby making it nice and simple to
read.

Signed-off-by: Vikas Shivappa <vikas.shivappa@xxxxxxxxxxxxxxx>
---
 arch/x86/include/asm/intel_rdt.h         |  4 ++++
 arch/x86/kernel/cpu/intel_rdt.c          | 30 ++++++++++++++++++++++++++++++
 arch/x86/kernel/cpu/intel_rdt_schemata.c |  5 +++--
 3 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/intel_rdt.h b/arch/x86/include/asm/intel_rdt.h
index d770527..3f31399 100644
--- a/arch/x86/include/asm/intel_rdt.h
+++ b/arch/x86/include/asm/intel_rdt.h
@@ -40,6 +40,8 @@ struct rdtgroup {
 /* List of all resource groups */
 extern struct list_head rdt_all_groups;
 
+extern int max_name_width, max_data_width;
+
 int __init rdtgroup_init(void);
 
 /**
@@ -73,6 +75,7 @@ struct rftype {
  * @name:			Name to use in "schemata" file
  * @num_closid:			Number of CLOSIDs available
  * @max_cbm:			Largest Cache Bit Mask allowed
+ * @data_width:		Character width of data when displaying
  * @min_cbm_bits:		Minimum number of consecutive bits to be set
  *				in a cache bit mask
  * @domains:			All domains for this resource
@@ -90,6 +93,7 @@ struct rdt_resource {
 	int			cbm_len;
 	int			min_cbm_bits;
 	u32			max_cbm;
+	int			data_width;
 	struct list_head	domains;
 	int			msr_base;
 	int			cache_level;
diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
index 329b887..70a3307 100644
--- a/arch/x86/kernel/cpu/intel_rdt.c
+++ b/arch/x86/kernel/cpu/intel_rdt.c
@@ -39,6 +39,12 @@
 
 #define domain_init(id) LIST_HEAD_INIT(rdt_resources_all[id].domains)
 
+/*
+ * Used to store the max resource name width and max resource data width
+ * to display the schemata in a tabular format
+ */
+int max_name_width, max_data_width;
+
 struct rdt_resource rdt_resources_all[] = {
 	{
 		.name		= "L3",
@@ -140,6 +146,7 @@ static void rdt_get_config(int idx, struct rdt_resource *r)
 	r->num_closid = edx.split.cos_max + 1;
 	r->cbm_len = eax.split.cbm_len + 1;
 	r->max_cbm = BIT_MASK(eax.split.cbm_len + 1) - 1;
+	r->data_width = (r->cbm_len + 3) / 4;
 	r->capable = true;
 	r->enabled = true;
 }
@@ -152,6 +159,7 @@ static void rdt_get_cdp_l3_config(int type)
 	r->num_closid = r_l3->num_closid / 2;
 	r->cbm_len = r_l3->cbm_len;
 	r->max_cbm = r_l3->max_cbm;
+	r->data_width = (r->cbm_len + 3) / 4;
 	r->capable = true;
 	/*
 	 * By default, CDP is disabled. CDP can be enabled by mount parameter
@@ -160,6 +168,26 @@ static void rdt_get_cdp_l3_config(int type)
 	r->enabled = false;
 }
 
+/**
+ * Choose a width for the resource name
+ * and resource data based on the resource that has
+ * widest name and cbm.
+ */
+static void rdt_init_padding(void)
+{
+	struct rdt_resource *r;
+	int cl;
+
+	for_each_enabled_rdt_resource(r) {
+		cl = strlen(r->name);
+		if (cl > max_name_width)
+			max_name_width = cl;
+
+		if (r->data_width > max_data_width)
+			max_data_width = r->data_width;
+	}
+}
+
 static inline bool get_rdt_resources(void)
 {
 	bool ret = false;
@@ -184,6 +212,8 @@ static inline bool get_rdt_resources(void)
 		ret = true;
 	}
 
+	rdt_init_padding();
+
 	return ret;
 }
 
diff --git a/arch/x86/kernel/cpu/intel_rdt_schemata.c b/arch/x86/kernel/cpu/intel_rdt_schemata.c
index 52e83ea..8594db4 100644
--- a/arch/x86/kernel/cpu/intel_rdt_schemata.c
+++ b/arch/x86/kernel/cpu/intel_rdt_schemata.c
@@ -203,11 +203,12 @@ static void show_doms(struct seq_file *s, struct rdt_resource *r, int closid)
 	struct rdt_domain *dom;
 	bool sep = false;
 
-	seq_printf(s, "%s:", r->name);
+	seq_printf(s, "%*s:", max_name_width, r->name);
 	list_for_each_entry(dom, &r->domains, list) {
 		if (sep)
 			seq_puts(s, ";");
-		seq_printf(s, "%d=%x", dom->id, dom->cbm[closid]);
+		seq_printf(s, "%d=%0*x", dom->id, max_data_width,
+			   dom->cbm[closid]);
 		sep = true;
 	}
 	seq_puts(s, "\n");
-- 
1.9.1