linux-kernel - RE: [PATCH v13 11/27] x86/resctrl: Implement resctrl_arch_config

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Message-ID: <SJ1PR11MB6083C5179F98E3873CA34C35FC99A@SJ1PR11MB6083.namprd11.prod.outlook.com>
Date: Thu, 22 May 2025 22:16:16 +0000
From: "Luck, Tony" <tony.luck@...el.com>
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Subject: RE: [PATCH v13 11/27] x86/resctrl: Implement
 resctrl_arch_config_cntr() to assign a counter with ABMC

> It looks to me as though there are a couple of changes in the telemetry work
> that would benefit this work. https://lore.kernel.org/lkml/20250521225049.132551-2-tony.luck@intel.com/
> switches the monitor events to be maintained in an array indexed by event ID, eliminating the
> need for searching the evt_list that this work does in a couple of places. Also note the handy
> new for_each_mbm_event() helper (https://lore.kernel.org/lkml/20250521225049.132551-5-tony.luck@intel.com/).

Yesterday I ran through the exercise of rebasing my AET patches on top of these
ABMC patches in order to check whether the ABMC patches painted resctrl
into some corner that would be hard to get back out of.

Good news: they don't.

There was a bunch of manual patching to make the first four patches fit on top
of the ABMC code, but I also noticed a few places where things were simpler
after combining the two series.

Maybe a good path forward would be to take those first four patches from
my AET series and then build ABMC on top of those.

-Tony