Message-ID: <4c33772b-fbb8-70ae-cbbb-2d93cc87e4f7@intel.com>
Date:   Wed, 15 Mar 2023 11:43:26 -0700
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Subject: Re: [PATCH v3 6/7] x86/resctrl: Introduce -o debug mount option
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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>,
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        <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>
 <167778870113.1053859.9553109061915206299.stgit@bmoger-ubuntu>
From:   Reinette Chatre <reinette.chatre@intel.com>
In-Reply-To: <167778870113.1053859.9553109061915206299.stgit@bmoger-ubuntu>
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Hi Babu,

On 3/2/2023 12:25 PM, Babu Moger wrote:
> 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          |    2 ++
>  arch/x86/kernel/cpu/resctrl/internal.h |    1 +
>  arch/x86/kernel/cpu/resctrl/rdtgroup.c |   13 +++++++++++++
>  3 files changed, 16 insertions(+)
> 
> diff --git a/Documentation/x86/resctrl.rst b/Documentation/x86/resctrl.rst
> index 67eae74fe40c..1ada4e0650dc 100644
> --- a/Documentation/x86/resctrl.rst
> +++ b/Documentation/x86/resctrl.rst
> @@ -46,6 +46,8 @@ mount options are:
>  "mba_MBps":
>  	Enable the MBA Software Controller(mba_sc) to specify MBA
>  	bandwidth in MBps
> +"debug":
> +	Lists the debug files in resctrl interface
>  

This seems to imply that a listing of available debug flags
will be displayed. How about something like "Make debug files
accessible. Available debug files are annotated with "Available
only with debug option"." (please feel free to improve).

>  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 6767c85b9699..35a9ee343fe0 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				debug;

Why not follow the prefix of existing flags?

>  };
>  
>  static inline struct rdt_fs_context *rdt_fc2context(struct fs_context *fc)

Reinette