diff mbox series

[v4,5/7] x86/resctrl: Introduce "-o debug" mount option

Message ID 168177448739.1758847.17451432454091802068.stgit@bmoger-ubuntu
State New
Headers
Series x86/resctrl: Miscellaneous resctrl features |

Commit Message

Moger, Babu April 17, 2023, 11:34 p.m. UTC 
  Add "-o debug" option to mount resctrl filesystem in debug mode.
Debug option adds the files for debug purposes.

Signed-off-by: Babu Moger <babu.moger@amd.com>
---
 Documentation/x86/resctrl.rst          |    3 +++
 arch/x86/kernel/cpu/resctrl/internal.h |    1 +
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |   13 +++++++++++++
 3 files changed, 17 insertions(+)

Comments

Reinette Chatre May 4, 2023, 7:02 p.m. UTC | #1 
Hi Babu,

On 4/17/2023 4:34 PM, Babu Moger wrote:
> Add "-o debug" option to mount resctrl filesystem in debug mode.
> Debug option adds the files for debug purposes.
> 

Could this changelog please be expanded to explain what "debug mode"
is, why is it necessary, and what will it be used for?

The changelog mentions "adds the files for debug purposes" but does
not explain what is meant by "the files" nor what these
files may look like or what "debug purposes" may be.

Reinette
Moger, Babu May 5, 2023, 9:26 p.m. UTC | #2 
On 5/4/2023 2:02 PM, Reinette Chatre wrote:
> Hi Babu,
>
> On 4/17/2023 4:34 PM, Babu Moger wrote:
>> Add "-o debug" option to mount resctrl filesystem in debug mode.
>> Debug option adds the files for debug purposes.
>>
> Could this changelog please be expanded to explain what "debug mode"
> is, why is it necessary, and what will it be used for?
>
> The changelog mentions "adds the files for debug purposes" but does
> not explain what is meant by "the files" nor what these
> files may look like or what "debug purposes" may be.


Sure. Will add the more details.

Thanks

Babu
diff mbox series

Patch

diff --git a/Documentation/x86/resctrl.rst b/Documentation/x86/resctrl.rst
index f28ed1443a6a..be443251b484 100644
--- a/Documentation/x86/resctrl.rst
+++ b/Documentation/x86/resctrl.rst
@@ -46,6 +46,9 @@  mount options are:
 "mba_MBps":
 	Enable the MBA Software Controller(mba_sc) to specify MBA
 	bandwidth in MBps
+"debug":
+	Make debug files accessible. Available debug files are annotated with
+	"Available only with debug option".
 
 L2 and L3 CDP are controlled separately.
 
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 75ddbd833fdf..1eac07ebc31b 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -59,6 +59,7 @@  struct rdt_fs_context {
 	bool				enable_cdpl2;
 	bool				enable_cdpl3;
 	bool				enable_mba_mbps;
+	bool				enable_debug;
 };
 
 static inline struct rdt_fs_context *rdt_fc2context(struct fs_context *fc)
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 719e29248892..0169821bc08c 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -56,6 +56,8 @@  static char last_cmd_status_buf[512];
 
 struct dentry *debugfs_resctrl;
 
+static bool resctrl_debug;
+
 void rdt_last_cmd_clear(void)
 {
 	lockdep_assert_held(&rdtgroup_mutex);
@@ -2387,6 +2389,9 @@  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)
+		resctrl_debug = true;
+
 	return ret;
 }
 
@@ -2575,6 +2580,7 @@  enum rdt_param {
 	Opt_cdp,
 	Opt_cdpl2,
 	Opt_mba_mbps,
+	Opt_debug,
 	nr__rdt_params
 };
 
@@ -2582,6 +2588,7 @@  static const struct fs_parameter_spec rdt_fs_parameters[] = {
 	fsparam_flag("cdp",		Opt_cdp),
 	fsparam_flag("cdpl2",		Opt_cdpl2),
 	fsparam_flag("mba_MBps",	Opt_mba_mbps),
+	fsparam_flag("debug",		Opt_debug),
 	{}
 };
 
@@ -2607,6 +2614,9 @@  static int rdt_parse_param(struct fs_context *fc, struct fs_parameter *param)
 			return -EINVAL;
 		ctx->enable_mba_mbps = true;
 		return 0;
+	case Opt_debug:
+		ctx->enable_debug = true;
+		return 0;
 	}
 
 	return -EINVAL;
@@ -3549,6 +3559,9 @@  static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf)
 	if (is_mba_sc(&rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl))
 		seq_puts(seq, ",mba_MBps");
 
+	if (resctrl_debug)
+		seq_puts(seq, ",debug");
+
 	return 0;
 }