linux-kernel - Re: [PATCH RFC] x86: avoid atomic operation in test_and_set_bit

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]

Message-ID: <20110324173020.GA26761@sgi.com>
Date:	Thu, 24 Mar 2011 12:30:20 -0500
From:	Jack Steiner <steiner@....com>
To:	Jan Beulich <JBeulich@...ell.com>
Cc:	Borislav Petkov <bp@...64.org>, Ingo Molnar <mingo@...e.hu>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Nick Piggin <npiggin@...nel.dk>,
	"x86@...nel.org" <x86@...nel.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Ingo Molnar <mingo@...hat.com>, tee@....com,
	Nikanth Karthikesan <knikanth@...e.de>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"H. Peter Anvin" <hpa@...or.com>
Subject: Re: [PATCH RFC] x86: avoid atomic operation in
	test_and_set_bit_lock if possible

> 
> This cacheline bouncing was actually observed and measured
> on SGI UV systems, but I'm not certain we're permitted to publish
> that data. I'm copying the two SGI guys who had reported that
> issue (and the special case fix, which Nikanth simply generalized)
> to us, for them to decide.

We frequently run into the cacheline bouncing issues. I don't have
the data handy that you refer to, but feel free to publish it.

--- jack


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/