RE: [PATCH v6 01/11] x86/tsc: Add base clock properties in clocksource structure

[D, Lakshmi Sowjanya]

> -----Original Message-----
> From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Sent: Thursday, April 11, 2024 2:51 AM
> To: D, Lakshmi Sowjanya <lakshmi.sowjanya.d@xxxxxxxxx>;
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> Subramanian <subramanian.mohan@xxxxxxxxx>; T R, Thejesh Reddy
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> Subject: Re: [PATCH v6 01/11] x86/tsc: Add base clock properties in clocksource
> structure
> 
> On Wed, Apr 10 2024 at 17:18, lakshmi.sowjanya.d@xxxxxxxxx wrote:
> > From: Lakshmi Sowjanya D <lakshmi.sowjanya.d@xxxxxxxxx>
> >
> > Add base clock hardware abstraction in clocksource structure.
> >
> > Add clocksource ID for x86 ART(Always Running Timer). The newly added
> > clocksource ID and conversion parameters are used to convert time in a
> > clocksource domain to base clock and vice versa.
> >
> > Convert the base clock to the system clock using convert_base_to_cs()
> > in get_device_system_crosststamp().
> 
> In https://lore.kernel.org/all/875xxhi1ty.ffs@tglx I asked you to provide a
> change log which explains the WHY and not the WHAT. The new change log still
> fails to explain WHY this change is needed and which problem it is trying to
> solve.

Rephrased the commit message to:
" Add base clock hardware abstraction in clocksource structure.

The core code has a mechanism to convert the ART base clock to
the corresponding tsc value. 
Provide the generic functionality in convert_base_to_cs() to convert
base clock timestamps to system clocksource without requiring
architecture specific parameters.

Add the infrastructure in get_device_system_crosststamp()."

> 
> I further asked you to do:
> 
>     1) Add the clocksource_base struct and provide the infrastructure in
>        get_device_system_crosststamp()
> 
>     2) Make TSC/ART use it
> 
> But this still does #1 and #2 in one go.
> 
> If you don't understand my review comments, then please ask. If you disagree
> with them then please tell me and argue with me.
> 
> Just ignoring them is not an option.

Sorry Thomas, that was a mis-understanding. We had split only realtime as separate patch.
We will split the first patch as suggested. 
	1. Timekeeping part(convert_base_to_cs() and infrastructure in get_device_system_crosststamp())
	2. x86(TSC/ART values update into the structure)

Thanks,
Sowjanya

> 
> Thanks,
> 
>         tglx