linux-kernel - RE: [PATCH 5/7] x86/resctrl: Add a new "snc_ways" file to the monitoring info directory.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 28 Feb 2023 17:44:23 +0000
From:   "Luck, Tony" <tony.luck@...el.com>
To:     James Morse <james.morse@....com>,
        "Yu, Fenghua" <fenghua.yu@...el.com>,
        "Chatre, Reinette" <reinette.chatre@...el.com>,
        Peter Newman <peternewman@...gle.com>,
        Jonathan Corbet <corbet@....net>,
        "x86@...nel.org" <x86@...nel.org>
CC:     Shaopeng Tan <tan.shaopeng@...itsu.com>,
        Jamie Iles <quic_jiles@...cinc.com>,
        Babu Moger <babu.moger@....com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-doc@...r.kernel.org" <linux-doc@...r.kernel.org>,
        "patches@...ts.linux.dev" <patches@...ts.linux.dev>
Subject: RE: [PATCH 5/7] x86/resctrl: Add a new "snc_ways" file to the
 monitoring info directory.

> > Make it easy for the user to tell if Sub-NUMA Cluster is enabled by
> > providing an info/ file.
>
> I think what this is conveying to user-space is 'domain_id_is_numa_node'.

That seems more architecturally neutral. I like it.

> Does user-space need to know the number of ways?

I don't know. Maybe some might. Perhaps there is some better name that
is architecturally neutral, but still has a numerical rather than boolean value?

> Will this always be a single number, or will it ever be possible to have an SNC=2 and
> SNC=1 package in the same system?

I sincerely hope that it is the same value across the system. Currently the
BIOS setup option to enable SNC doesn't have per-socket choices, it is
just an all-or-nothing choice. "2" isn't the only choice for number of SNC
nodes on a socket. "4" is (or will be) a choice.

-Tony