Re: [PATCH v4 18/24] x86/resctrl: Make ctrlval arrays the same size

From: Reinette Chatre
Date: Tue Jun 15 2021 - 14:09:21 EST


Hi James,

On 6/14/2021 1:09 PM, James Morse wrote:
The CODE and DATA resources report a num_closid that is half the
actual size supported by the hardware. This behaviour is visible
to user-space when CDP is enabled.
The CODE and DATA resources have their own ctrlval arrays which are half
the size of the underlying hardware because num_closid was already
adjusted. One holds the odd configurations values, the other even.

Before the CDP resources can be merged, the 'half the closids'
behaviour needs to be implemented by schemata_list_create(), but
this causes the ctrl_val[] array to be full sized.

Remove the logic from the architecture specific rdt_get_cdp_config()
setup, and add it to schemata_list_create(). Functions that
walk take num_closid directly from struct rdt_hw_resource also

This is unclear to me ... "Functions that walk ..." seems like it is missing to describe what they are walking.

have to halve num_closid as only the lower half of each array is
in use. domain_setup_ctrlval() and reset_all_ctrls() both copy
struct rdt_hw_resource's num_closid to a struct msr_param. Correct
the value here. This is temporary as a subsequent patch will merge
the all three ctrl_val[] arrays such that when CDP is in use, the

the all three -> all three ?

Reinette