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 <s...@fb.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
