linux-kernel - Re: [PATCH v2 2/3] Documentation, ABI: Add a document entry for cache id

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:	Fri, 8 Jul 2016 20:07:46 +0200
From:	Ingo Molnar <mingo@...nel.org>
To:	"Luck, Tony" <tony.luck@...el.com>
Cc:	"Yu, Fenghua" <fenghua.yu@...el.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	"Anvin, H Peter" <h.peter.anvin@...el.com>,
	Ingo Molnar <mingo@...e.hu>, Borislav Petkov <bp@...e.de>,
	Stephane Eranian <eranian@...gle.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Vikas Shivappa <vikas.shivappa@...ux.intel.com>,
	"Shankar, Ravi V" <ravi.v.shankar@...el.com>,
	linux-kernel <linux-kernel@...r.kernel.org>, x86 <x86@...nel.org>
Subject: Re: [PATCH v2 2/3] Documentation, ABI: Add a document entry for
 cache id


* Luck, Tony <tony.luck@...el.com> wrote:

> > It means one cache's id is unique in all caches with same cache index number.
> > For example, in all caches with index3 (i.e. level3), cache id 0 is unique to identify
> > a L3 cache. But in caches with index 0 (i.e. Level0), there is also a cache id 0.
> > So cache id is unique in one index. But not unique in two different index.
> 
> > Does that make sense? I hope I express that correctly.
> 
> We use "index" rather than "level" because that is the terminology used
> in /sys/devices/system/cpu/cpu*/cache/index*

Who can we ... thank for that nonsensical naming? :-/

> E.g. on most Intel cpus you'll typically find "index0" is the L1-data cache, 
> "index1" is the L1-instruction cache, "index3" is the L2-unified cache and 
> "index4" is the L3-unified cache.

Crazy. What was wrong with using 'level' or 'depth'?

Thanks,

	Ingo