linux-kernel - [PATCH 2/2] intel_rdt: export min_cbm

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Date:   Thu, 3 Nov 2016 14:09:06 -0700
From:   Shaohua Li <shli@...com>
To:     <linux-kernel@...r.kernel.org>
CC:     <fenghua.yu@...el.com>, <tony.luck@...el.com>, <tglx@...utronix.de>
Subject: [PATCH 2/2] intel_rdt: export min_cbm_bits

min_cbm_bits could be 1 or 2 for L3 cache. Kenrel does check the bits
when writting mask. Unfortunately it's not exported to userspace. This
patch fixes the gap.

Signed-off-by: Shaohua Li <shli@...com>
---
 arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index e66c7a5..4795880 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -472,6 +472,16 @@ static int rdt_cbm_mask_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+static int rdt_min_cbm_bits_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_cbm_bits);
+
+	return 0;
+}
+
 /* rdtgroup information files for one cache resource. */
 static struct rftype res_info_files[] = {
 	{
@@ -486,6 +496,12 @@ static struct rftype res_info_files[] = {
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_cbm_mask_show,
 	},
+	{
+		.name		= "min_cbm_bits",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_min_cbm_bits_show,
+	},
 };
 
 static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn)
-- 
2.9.3