Re: [PATCH v8 4/8] x86/resctrl: Add comments on RFTYPE flags hierarchy

[Moger, Babu]

Hi Fenghua,

On 9/1/2023 5:31 PM, Fenghua Yu wrote:
> Hi, Babu,
>
> On 8/21/23 16:30, Babu Moger wrote:
> > resctrl uses RFTYPE flags for creating resctrl directory structure.
> >
> > Definitions and directory structures are not documented. Add
> > comments to improve the readability and help future additions.
> >
> > Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
> > ---
> >   arch/x86/kernel/cpu/resctrl/internal.h | 58 ++++++++++++++++++++++++++
> >   1 file changed, 58 insertions(+)
> >
> > diff --git a/arch/x86/kernel/cpu/resctrl/internal.h 
> > b/arch/x86/kernel/cpu/resctrl/internal.h
> > index 2051179a3b91..b09e7abd1299 100644
> > --- a/arch/x86/kernel/cpu/resctrl/internal.h
> > +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> > @@ -240,6 +240,64 @@ struct rdtgroup {
> >     /*
> >    * Define the file type flags for base and info directories.
> > + *
> > + * RESCTRL filesystem has two main components
> > + *    a. info
> > + *    b. base
> > + *
> > + * /sys/fs/resctrl/
> > + *    |
> > + *    --> info (Top level directory named "info". Contains files that
> > + *    |      provide details on control and monitoring resources.)
> > + *    |
> > + *    --> base (Root directory associated with default resource group
> > + *          as well as directories created by user for MON and CTRL
> > + *          groups. Contains files to interact with MON and CTRL
> > + *          groups.)
> > + *
> > + *    Note: resctrl uses flags for files, not for directories.
> > + *          Directories are created based on the resource type. Added
> > + *          directories below for better understanding.
> > + *
> > + *    info directory structure
> > + * ------------------------------------------------------------------
> > + *    --> RFTYPE_INFO
> > + *        directory: info
> > + *        --> RFTYPE_TOP (Files in top level of info directory)
> > + *            File: last_cmd_status
> > + *
> > + *        --> RFTYPE_MON (Files for all monitoring resources)
> > + *            Directory: L3_MON
> > + *                Files: mon_features, num_rmids
> > + *
> > + *            --> RFTYPE_RES_CACHE (Files for cache monitoring 
> > resources)
> > + *                Directory: L3_MON
> > + *                    Files: max_threshold_occupancy,
> > + *                           mbm_total_bytes_config,
> > + *                           mbm_local_bytes_config
> > + *
> > + *        --> RFTYPE_CTRL (Files for all control resources)
> > + *            Directories: L2, L3, MB, SMBA
>
> L2 CDP and L3 CDP have different dirs. So need to add them here:
>
>  + *            Directories: L2, L3, MB, SMBA, L2CODE, L2DATA, L3CODE, 
> L3DATA (L*CODE and L*DATA only available when CDP is enabled)
Sure.


> > + *                   File: num_closids
> > + *
> > + *            --> RFTYPE_RES_CACHE (Files for cache control resources)
> > + *                Directories: L2, L3
>
> > + *                Directories: L2, L3
>
> + *                Directories: L2, L3, L2CODE, L2DATA, L3CODE, L3DATA
Yes. Sure.

Thank you

Babu