Re: [PATCH 2/5] x86/intel_rdt: Improvements to parsing schemata

From: Shivappa Vikas
Date: Fri Mar 10 2017 - 13:24:25 EST




On Fri, 10 Mar 2017, Thomas Gleixner wrote:

On Thu, 9 Mar 2017, Shivappa Vikas wrote:


Anyway, first of all we want to know WHY this ordering is required. If it's
not required then why would we enforce it?

Do the users want to see the data in the same order they entered ? If we want
to do that then its easy to implement when we enforce the order .. (because
right now resources are always displayed in a predefined order).
Otherwise i can drop this patch.

It's fine to display them in a defined order, but there is no point to
enforce the ordering on write.

The real question here is whether we really have to write every line on
every update. IMO it's sufficient to write a single resource line and not
require to update all resources every time.

Ok in that case we can drop this. because my thought was that user wants to see the contents he wrote when he overwrites the whole file like below , IOW its wierd for user to do

# echo "L3:0=0xff;1=0xf0" > /sys/fs/resctrl/schemata
then

# cat /sys/fs/resctrl/schemata
L3:0=0xff;1=0xf0
L2:0=0xff;1=0xf0
MB:....

But he did not write the L2,MB when he did an overwrite of the whole file.


Thanks,
Vikas


Thanks,

tglx