Re: [PATCH 4/4] selftests/resctrl: Adjust SNC support messages

[Tony Luck]

On Thu, Mar 07, 2024 at 02:39:08PM -0800, Reinette Chatre wrote:
> Thank you for the example. I find that significantly easier to
> understand than a single number in a generic "nodes_per_l3_cache".
> Especially with potential confusion surrounding inconsistent "nodes"
> between allocation and monitoring. 
> 
> How about domain_cpu_list and domain_cpu_map ?

Reinette,

Like this (my test system doesn't have SNC, so all domains are the same):

$ cd /sys/fs/resctrl/info/
$ grep . */domain*
L3/domain_cpu_list:0: 0-35,72-107
L3/domain_cpu_list:1: 36-71,108-143
L3/domain_cpu_map:0: 0000,00000fff,ffffff00,0000000f,ffffffff
L3/domain_cpu_map:1: ffff,fffff000,000000ff,fffffff0,00000000
L3_MON/domain_cpu_list:0: 0-35,72-107
L3_MON/domain_cpu_list:1: 36-71,108-143
L3_MON/domain_cpu_map:0: 0000,00000fff,ffffff00,0000000f,ffffffff
L3_MON/domain_cpu_map:1: ffff,fffff000,000000ff,fffffff0,00000000
MB/domain_cpu_list:0: 0-35,72-107
MB/domain_cpu_list:1: 36-71,108-143
MB/domain_cpu_map:0: 0000,00000fff,ffffff00,0000000f,ffffffff
MB/domain_cpu_map:1: ffff,fffff000,000000ff,fffffff0,00000000


The patch to do this is pretty straightforward.

-Tony

---

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index ae80170a0d1b..c180b80640e3 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -957,6 +957,20 @@ static int rdt_num_closids_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+static int rdt_ctrl_cpus_show(struct kernfs_open_file *of,
+			      struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = of->kn->parent->priv;
+	struct rdt_resource *r = s->res;
+	struct rdt_ctrl_domain *d;
+
+	list_for_each_entry(d, &r->ctrl_domains, hdr.list)
+		seq_printf(seq, is_cpu_list(of) ? "%d: %*pbl\n" : "%d: %*pb\n",
+			   d->hdr.id, cpumask_pr_args(&d->hdr.cpu_mask));
+
+	return 0;
+}
+
 static int rdt_default_ctrl_show(struct kernfs_open_file *of,
 			     struct seq_file *seq, void *v)
 {
@@ -1103,6 +1117,19 @@ static int rdt_num_rmids_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+static int rdt_mon_cpus_show(struct kernfs_open_file *of,
+			     struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+	struct rdt_mon_domain *d;
+
+	list_for_each_entry(d, &r->mon_domains, hdr.list)
+		seq_printf(seq, is_cpu_list(of) ? "%d: %*pbl\n" : "%d: %*pb\n",
+			   d->hdr.id, cpumask_pr_args(&d->hdr.cpu_mask));
+
+	return 0;
+}
+
 static int rdt_mon_features_show(struct kernfs_open_file *of,
 				 struct seq_file *seq, void *v)
 {
@@ -1810,6 +1837,21 @@ static struct rftype res_common_files[] = {
 		.seq_show	= rdt_num_closids_show,
 		.fflags		= RFTYPE_CTRL_INFO,
 	},
+	{
+		.name		= "domain_cpu_list",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_ctrl_cpus_show,
+		.flags		= RFTYPE_FLAGS_CPUS_LIST,
+		.fflags		= RFTYPE_CTRL_INFO,
+	},
+	{
+		.name		= "domain_cpu_map",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_ctrl_cpus_show,
+		.fflags		= RFTYPE_CTRL_INFO,
+	},
 	{
 		.name		= "mon_features",
 		.mode		= 0444,
@@ -1824,6 +1866,21 @@ static struct rftype res_common_files[] = {
 		.seq_show	= rdt_num_rmids_show,
 		.fflags		= RFTYPE_MON_INFO,
 	},
+	{
+		.name		= "domain_cpu_list",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_mon_cpus_show,
+		.flags		= RFTYPE_FLAGS_CPUS_LIST,
+		.fflags		= RFTYPE_MON_INFO,
+	},
+	{
+		.name		= "domain_cpu_map",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_mon_cpus_show,
+		.fflags		= RFTYPE_MON_INFO,
+	},
 	{
 		.name		= "cbm_mask",
 		.mode		= 0444,
-- 
2.43.0