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Subject: [PATCH v6 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:   Wed, 19 Jul 2023 18:21:55 -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 |   48 ++++++++++++++++++++++++++++=
++++=0A=
 1 file changed, 48 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..783c3e36633c 100644=0A=
--- a/arch/x86/kernel/cpu/resctrl/internal.h=0A=
+++ b/arch/x86/kernel/cpu/resctrl/internal.h=0A=
@@ -240,6 +240,54 @@ 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 (Top level directory named "info". Contains files that=0A=
+ *	|	  provide details on control and monitoring resources.)=0A=
+ *	|=0A=
+ *	--> base (Root directory associated with default resource group=0A=
+ *		  as well as directories created by user for MON and CTRL=0A=
+ *		  groups. Contains files to interact with MON and CTRL=0A=
+ *		  groups.)=0A=
+ *=0A=
+ *	info directory 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, mon_features,=0A=
+ *		           num_rmids, mbm_total_bytes_config,=0A=
+ *		           mbm_locat_bytes_config=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,=0A=
+ * 			           min_bandwidth, num_closids,=0A=
+ *			           thread_throttle_mode=0A=
+ *=0A=
+ *	base (root) directory 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=
  */=0A=
 #define RFTYPE_INFO			BIT(0)=0A=
 #define RFTYPE_BASE			BIT(1)=0A=
=0A=