Message-ID: <26400c6a-dcde-9ac2-df7a-117a12875f0c@intel.com>
Date:   Wed, 15 Mar 2023 11:37:40 -0700
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101
 Firefox/102.0 Thunderbird/102.8.0
Subject: Re: [PATCH v3 4/7] x86/resctrl: Re-arrange RFTYPE flags based on
 hierarchy
Content-Language: en-US
To:     Babu Moger <babu.moger@amd.com>, <corbet@lwn.net>,
        <tglx@linutronix.de>, <mingo@redhat.com>, <bp@alien8.de>
CC:     <fenghua.yu@intel.com>, <dave.hansen@linux.intel.com>,
        <x86@kernel.org>, <hpa@zytor.com>, <paulmck@kernel.org>,
        <akpm@linux-foundation.org>, <quic_neeraju@quicinc.com>,
        <rdunlap@infradead.org>, <damien.lemoal@opensource.wdc.com>,
        <songmuchun@bytedance.com>, <peterz@infradead.org>,
        <jpoimboe@kernel.org>, <pbonzini@redhat.com>,
        <chang.seok.bae@intel.com>, <pawan.kumar.gupta@linux.intel.com>,
        <jmattson@google.com>, <daniel.sneddon@linux.intel.com>,
        <sandipan.das@amd.com>, <tony.luck@intel.com>,
        <james.morse@arm.com>, <linux-doc@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <bagasdotme@gmail.com>,
        <eranian@google.com>, <christophe.leroy@csgroup.eu>,
        <jarkko@kernel.org>, <adrian.hunter@intel.com>,
        <quic_jiles@quicinc.com>, <peternewman@google.com>
References: <167778850105.1053859.14596357862185564029.stgit@bmoger-ubuntu>
 <167778868692.1053859.13490646651097380957.stgit@bmoger-ubuntu>
From:   Reinette Chatre <reinette.chatre@intel.com>
In-Reply-To: <167778868692.1053859.13490646651097380957.stgit@bmoger-ubuntu>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?NnhMVVRpQ0JlYWh6R2VreUcyNVg3bVNLUnRiZlJmRkl6dUNUeU1JaHkwYjJy?=
 =?utf-8?B?cmhPTDVCOVJwWGNOS1hCNU8vOENmVEhKRFpNMi9rM0F0N0NmWWp6cmdEazRl?=
 =?utf-8?B?dTE5Tk9kU3RhUnBFR1VuOWpJSWxqbU1jUm1vclpBVjFIdERySWdkNDF1ZVpO?=
 =?utf-8?B?Z1NHYzhoMGhJVzEzNk9rbnVVUll2cEZ4OW1NQjRqNDMzMGpSR0F6eDdhRDR2?=
 =?utf-8?B?eVUvejl3Ykk5N3pVT0N6VXAwUWxtSzZ6NlprcE5uWEIwMFNHd1o1QWNMbm1M?=
 =?utf-8?B?Zy9tbjlDM1FKWTRFeXdQS1lKNEtVL01EUnYzOWpnSjE4TXErMTlXVnoxQ2Vs?=
 =?utf-8?B?Sm13Q0VrWkRpTmxLZ1pZYVVwam80RjIwZ3g5dFFyRWlpTHNocUFQMjBPR1p4?=
 =?utf-8?B?ejZsU0svRjYxUXVPVmp2Znh4MFQ4am0xTFFMeXgvZ09SRDJnWjJZOFRybUtR?=
 =?utf-8?B?QU10MURsek1sSHI4cU05YUJDUm9nS1Q1ZHV5TTlMMjY0d3RjMVVnK2FhOG4x?=
 =?utf-8?B?TlM3ZjhkaVU4UmZQWCtWNm5RUitPV1BPMFNydFNzYUFBYU44a3grbHgyM3I4?=
 =?utf-8?B?L0xQTkJrcENvQ1p4eFdCeTYzSWVYQTNVKzIxWk00WTFLdzBqMXU3N3Y1Sk1H?=
 =?utf-8?B?NEZsTG56MDlndFJCYXBpU3hndWowNnpRNE9wY3hzNHRzNmc1dHpNWG81QjVz?=
 =?utf-8?B?VSs2a0tQK3lpbkNQeEs0UHRFaVllKzVNc3BrR3VkckRkT0xQbldQTWJ0TzQz?=
 =?utf-8?B?UzlGeThKUllDL2prRGFMNjZXb1dGcElRZ1pLc2lWYThQNTIzSUhmOGozbTJo?=
 =?utf-8?B?Q2JsYXJjYmNZRjFPZ01Ici82bG5SZFIwOVM3QWpwNUN2MVNhVHZsNWpaRStE?=
 =?utf-8?B?UzI4L1NGK0hxVFN6YnhiNGtGMGtYSmpOVFBmQkUxZFVpdmgxa3pBTkY5THVn?=
 =?utf-8?B?OTFKVXBGV0dHUWtXcUxQZ0lMSGRQSTFaMWMwa2h0U0RLLzRRaURJL0FycjdT?=
 =?utf-8?B?Mm51R0pXbHhmMzZtS1AwYkJFMnhnTHpLNWFZZ2VDSXJ1ay81K0prU083ajdm?=
 =?utf-8?B?NG1hUHRFc1AxcStPdVFoeDNCanlnSGZweGMvWGxwL0FWMVBNY29seGdpVWJX?=
 =?utf-8?B?SG1MZm81OGd5eHU3Z0l5Z1JwUnNPc0ZHVk5KK1loZk1LQytScGcwL3c0ZnBx?=
 =?utf-8?B?ODdDaWx5NlM2MVVoUlg3UTVkbVV3d1hZelQrcnltcU85eWFwVnRpK00xd2E0?=
 =?utf-8?B?ZU43cGtvZWl1S1BXNjFYQzBwTEp1VmVyaU45azUxbjFuRTg4aldITFNaSWJI?=
 =?utf-8?B?NEllZlNqUFlNcVNtaWtkQXhMbUJ5UXNDNHYxY2N5emFISzlhVFU2akZDYXM3?=
 =?utf-8?B?eWx2T2RFT29XdC93eE9CR1ljYm42M0JYeERvSk9OMGQ1aFNmMHBMeWxEQ25O?=
 =?utf-8?B?TkhNM2k2dmsyL0c3ODgrd1hoQi95OFBBRmVNeFRheWR5dHJTLzh1ZTRCWkYx?=
 =?utf-8?B?anFXbmZmWnlsa3c5OG41L21wU0dMV3kxWWhOeUc5UkFlQ0pyZnVScGpKYzRl?=
 =?utf-8?B?a3ZlRm9neTBDUVU4dFhLL2V0QTh1T0pWZXhvOGFmV3JzMnVjc3VteXpQMzJx?=
 =?utf-8?B?bDdGSlMrYmw2SkFPUURwZkY3TjRyWmlHQ3VRTVVjRXQ4bkRERjhvZFBzaEIv?=
 =?utf-8?B?ZjBkcUVqMXgydmtDV2RPN2gyVEUxeWM3NEJQM25PTnpydEJScUdrOWJsZTRr?=
 =?utf-8?B?Z3BGTCs5Z29LRVlzRGJkaEpxOUxyU1NQTEVnd3hNSTI5amUrQ2pWbk1waHY5?=
 =?utf-8?B?T0NORVgrQlBTOUNka00yTndaTnJUM1EvN21kdEZJZklSdktraUYwSXVqK0Er?=
 =?utf-8?B?dklUWHB2N3BkOXAreU9zV04zUkt0MGF6cW8yeGpaWmVRbzZyY3FwM293S3N4?=
 =?utf-8?B?SmVOOXU3czYyME5JaUFhWmk0QVVydXl4Y0RzbEpBMDFwWUYwZk8yTmRTVXBY?=
 =?utf-8?B?TDhYQkk4ZTNrb0JtdGtRbGxqWDhsa3JrUFptZFlZWW9XMUJXMm1CbmV0Y0du?=
 =?utf-8?B?c245TkhFT0F6OTdaMFJHRXJ6NUQ5SWxOV1JaWDBEbVY1UDdNOVhpcHNjakFD?=
 =?utf-8?B?WlpLUi82ZnBEcU9IblJsQVl6eXd3M2lxNTVvSnVFeGVQaUpVcDcwNm5lVVpv?=
 =?utf-8?B?YlE9PQ==?=
X-MS-Exchange-CrossTenant-Network-Message-Id: 5b7908ac-364d-4674-a0c6-08db25845dce
X-MS-Exchange-CrossTenant-AuthSource: CY4PR11MB1862.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Mar 2023 18:37:44.5915
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: KlVEl9JQYAj6jjxwUratztoCsvVkypIQTTQHyij99P6NPYTPHv4274K2jlU4RKAhuM9HIvmnwK/Ju0/a+jdIoPH7IUNVaiwubjRxc716nxM=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PR11MB7814
X-OriginatorOrg: intel.com
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Hi Babu,

On 3/2/2023 12:24 PM, Babu Moger wrote:
> RESCTRL filesystem has two main components:
> a. info (Details on resources and monitoring)
> b. base (Details on CONTROL and MON groups)
> 
> The rftype flags can be renamed accordingly for better understanding.
> For example:
> RFTYPE_INFO     : Files with these flags go in info directory

This is not a rename but the current name.

> RFTYPE_INFO_MON : Files with these flags go in info/L3_MON

How does this improve the current RFTYPE_MON_INFO?

> RFTYPE_BASE     : Files with these flags go in group's(control or mon)
>                   base directory
This is not a rename but the current name.

> RFTYPE_BASE_CTRL: Files with these flags go in only CONTROL groups

How does this improve current RFTYPE_CTRL_BASE ?

> 
> Add comments to make it easy for future additions.
> 
> Signed-off-by: Babu Moger <babu.moger@amd.com>
> ---
>  arch/x86/kernel/cpu/resctrl/core.c     |    8 ++--
>  arch/x86/kernel/cpu/resctrl/internal.h |   64 ++++++++++++++++++++++++++++----
>  arch/x86/kernel/cpu/resctrl/rdtgroup.c |   44 +++++++++++-----------
>  3 files changed, 81 insertions(+), 35 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
> index 030d3b409768..d1c6b2cc8611 100644
> --- a/arch/x86/kernel/cpu/resctrl/core.c
> +++ b/arch/x86/kernel/cpu/resctrl/core.c
> @@ -69,7 +69,7 @@ struct rdt_hw_resource rdt_resources_all[] = {
>  			.domains		= domain_init(RDT_RESOURCE_L3),
>  			.parse_ctrlval		= parse_cbm,
>  			.format_str		= "%d=%0*x",
> -			.fflags			= RFTYPE_RES_CACHE,
> +			.fflags			= RFTYPE_CACHE,
>  		},

How does this rename improve understanding?

...

> @@ -97,7 +97,7 @@ struct rdt_hw_resource rdt_resources_all[] = {
>  			.domains		= domain_init(RDT_RESOURCE_MBA),
>  			.parse_ctrlval		= parse_bw,
>  			.format_str		= "%d=%*u",
> -			.fflags			= RFTYPE_RES_MB,
> +			.fflags			= RFTYPE_MB,
>  		},
>  	},
>  	[RDT_RESOURCE_SMBA] =

ditto.


...

> + *
>   */
>  #define RFTYPE_INFO			BIT(0)
>  #define RFTYPE_BASE			BIT(1)
> -#define RFTYPE_CTRL			BIT(4)
> -#define RFTYPE_MON			BIT(5)
> -#define RFTYPE_TOP			BIT(6)
> -#define RFTYPE_RES_CACHE		BIT(8)
> -#define RFTYPE_RES_MB			BIT(9)
> -#define RFTYPE_CTRL_INFO		(RFTYPE_INFO | RFTYPE_CTRL)
> -#define RFTYPE_MON_INFO			(RFTYPE_INFO | RFTYPE_MON)
> -#define RFTYPE_TOP_INFO			(RFTYPE_INFO | RFTYPE_TOP)
> -#define RFTYPE_CTRL_BASE		(RFTYPE_BASE | RFTYPE_CTRL)
> +
> +#define RFTYPE_TOP			BIT(2)
> +#define RFTYPE_MON			BIT(3)
> +#define RFTYPE_RES			BIT(4)
> +
> +#define RFTYPE_CACHE			BIT(5)
> +#define RFTYPE_MB			BIT(6)
> +
> +#define RFTYPE_CTRL			BIT(8)
> +
> +#define RFTYPE_INFO_TOP			(RFTYPE_INFO | RFTYPE_TOP)
> +#define RFTYPE_INFO_MON			(RFTYPE_INFO | RFTYPE_MON)
> +#define RFTYPE_INFO_RES			(RFTYPE_INFO | RFTYPE_RES)
> +
> +#define RFTYPE_BASE_CTRL		(RFTYPE_BASE | RFTYPE_CTRL)
>  

It is not clear to me how any of the renames improves understanding.

How does renaming RFTYPE_CTRL_BASE to RFTYPE_BASE_CTRL improve
understanding? Renaming RFTYPE_MON_INFO to RFTYPE_INFO_MON?

This all seems unnecessary.

...

> @@ -3218,7 +3218,7 @@ static int mkdir_rdt_prepare(struct kernfs_node *parent_kn,
>  	if (rtype == RDTCTRL_GROUP)
>  		fflags = RFTYPE_BASE | RFTYPE_CTRL;
>  	else
> -		fflags = RFTYPE_BASE | RFTYPE_MON;
> +		fflags = RFTYPE_BASE;
>  

Is this intended?

Reinette