[PATCH v4 7/7] x86/resctrl: Add debug files when mounted with debug option

Babu Moger
2023-04-17T23:36:14Z

Add the debug files to the resctrl hierarchy.

Signed-off-by: Babu Moger <babu.moger@amd.com>
---
arch/x86/kernel/cpu/resctrl/internal.h | 1 +
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 54 +++++++++++++++++++++++++++++++-
2 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 1eac07ebc31b..855109abb480 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -288,6 +288,7 @@ struct rdtgroup {
#define RFTYPE_TOP BIT(4)
#define RFTYPE_RES_CACHE BIT(5)
#define RFTYPE_RES_MB BIT(6)
+#define RFTYPE_DEBUG BIT(7)
#define RFTYPE_CTRL_INFO (RFTYPE_INFO | RFTYPE_CTRL)
#define RFTYPE_MON_INFO (RFTYPE_INFO | RFTYPE_MON)
#define RFTYPE_TOP_INFO (RFTYPE_INFO | RFTYPE_TOP)
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 15ded0dd5b09..1ec4359348c2 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1880,6 +1880,7 @@ static struct rftype res_common_files[] = {
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdtgroup_rmid_show,
+ .fflags = RFTYPE_BASE | RFTYPE_DEBUG,
},
{
.name = "schemata",
@@ -1909,6 +1910,7 @@ static struct rftype res_common_files[] = {
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdtgroup_closid_show,
+ .fflags = RFTYPE_CTRL_BASE | RFTYPE_DEBUG,
},

};
@@ -2420,6 +2422,49 @@ static int mkdir_mondata_all(struct kernfs_node *parent_kn,
struct rdtgroup *prgrp,
struct kernfs_node **mon_data_kn);

+static void resctrl_add_debug_files(void)
+{
+ struct rftype *rfts, *rft;
+ int len;
+
+ rfts = res_common_files;
+ len = ARRAY_SIZE(res_common_files);
+
+ lockdep_assert_held(&rdtgroup_mutex);
+
+ for (rft = rfts; rft < rfts + len; rft++) {
+ if (rft->fflags & RFTYPE_DEBUG) {
+ rft->fflags &= ~RFTYPE_DEBUG;
+ rdtgroup_add_file(rdtgroup_default.kn, rft);
+ }
+ }
+
+ kernfs_activate(rdtgroup_default.kn);
+}
+
+static void resctrl_remove_debug_files(void)
+{
+ struct rftype *rfts, *rft;
+ int len;
+
+ rfts = res_common_files;
+ len = ARRAY_SIZE(res_common_files);
+
+ lockdep_assert_held(&rdtgroup_mutex);
+
+ for (rft = rfts; rft < rfts + len; rft++) {
+ if (!strcmp(rft->name, "mon_hw_id")) {
+ rft->fflags |= RFTYPE_DEBUG;
+ kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
+ } else if (!strcmp(rft->name, "ctrl_hw_id")) {
+ rft->fflags |= RFTYPE_DEBUG;
+ kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
+ }
+ }
+
+ kernfs_activate(rdtgroup_default.kn);
+}
+
static int rdt_enable_ctx(struct rdt_fs_context *ctx)
{
int ret = 0;
@@ -2433,8 +2478,10 @@ static int rdt_enable_ctx(struct rdt_fs_context *ctx)
if (!ret && ctx->enable_mba_mbps)
ret = set_mba_sc(true);

- if (!ret && ctx->enable_debug)
+ if (!ret && ctx->enable_debug) {
resctrl_debug = true;
+ resctrl_add_debug_files();
+ }

return ret;
}
@@ -2851,6 +2898,11 @@ static void rdt_kill_sb(struct super_block *sb)

set_mba_sc(false);

+ if (resctrl_debug) {
+ resctrl_remove_debug_files();
+ resctrl_debug = false;
+ }
+
/*Put everything back to default values. */
for_each_alloc_capable_rdt_resource(r)
reset_all_ctrls(r);