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Subject: [PATCH v5 4/8] x86/resctrl: Add comments on RFTYPE flags hierarchy
From:   Babu Moger <babu.moger@amd.com>
To:     <corbet@lwn.net>, <reinette.chatre@intel.com>,
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Date:   Thu, 1 Jun 2023 14:01:31 -0500
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resctrl uses RFTYPE flags for creating resctrl directory structure.=0A=
=0A=
Definitions and directory structures are not documented. Add=0A=
comments to improve the readability and help future additions.=0A=
=0A=
Signed-off-by: Babu Moger <babu.moger@amd.com>=0A=
---=0A=
 arch/x86/kernel/cpu/resctrl/internal.h |   45 ++++++++++++++++++++++++++++=
++++=0A=
 1 file changed, 45 insertions(+)=0A=
=0A=
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/r=
esctrl/internal.h=0A=
index 2051179a3b91..c20cd6acb7a3 100644=0A=
--- a/arch/x86/kernel/cpu/resctrl/internal.h=0A=
+++ b/arch/x86/kernel/cpu/resctrl/internal.h=0A=
@@ -240,6 +240,51 @@ struct rdtgroup {=0A=
 =0A=
 /*=0A=
  * Define the file type flags for base and info directories.=0A=
+ *=0A=
+ * RESCTRL filesystem has two main components=0A=
+ *   a. info=0A=
+ *   b. base=0A=
+ *=0A=
+ * /sys/fs/resctrl/=0A=
+ *     |=0A=
+ *     --> info (directory and provides details on control=0A=
+ *     |         and monitoring resources)=0A=
+ *     |=0A=
+ *     --> base (Lists the files and information to interact with control=
=0A=
+ *               or monitor groups. Provides details on default control=0A=
+ *               group when filesystem is created. There is no directory=
=0A=
+ *               with name base)=0A=
+ *=0A=
+ *     info structure=0A=
+ *    -------------------------------------------------------------=0A=
+ *    --> RFTYPE_INFO=0A=
+ *        --> <info> directory=0A=
+ *            --> RFTYPE_TOP_INFO=0A=
+ *                Files: last_cmd_status=0A=
+ *=0A=
+ *        --> RFTYPE_MON_INFO=0A=
+ *            --> <L3_MON> directory=0A=
+ *                 Files: max_threshold_occupancy, mbm_local_bytes_config,=
=0A=
+ *                        mbm_total_bytes_config, mon_features, num_rmids=
=0A=
+ *=0A=
+ *        --> RFTYPE_CTRL_INFO=0A=
+ *            --> RFTYPE_RES_CACHE=0A=
+ *                --> <L2/L3> directory=0A=
+ *                     Files: bit_usage, cbm_mask, min_cbm_bits,=0A=
+ *                            num_closids, shareable_bits=0A=
+ *=0A=
+ *            --> RFTYPE_RES_MB=0A=
+ *                --> <MB/SMBA> directory=0A=
+ *                     Files: bandwidth_gran, delay_linear, min_bandwidth,=
=0A=
+ *                            num_closids=0A=
+ *=0A=
+ *     base structure=0A=
+ *     -----------------------------------------------------------=0A=
+ *     --> RFTYPE_BASE (Files common for both MON and CTRL groups)=0A=
+ *         Files: cpus, cpus_list, tasks=0A=
+ *=0A=
+ *     --> RFTYPE_CTRL_BASE (Files only for CTRL group)=0A=
+ *         Files: mode, schemata, size=0A=
  */=0A=
 #define RFTYPE_INFO			BIT(0)=0A=
 #define RFTYPE_BASE			BIT(1)=0A=
=0A=