linux-kernel - Re: [PATCH 0/6] x86: reduce paravirtualized spinlock overhead

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: <55425ADA.4060105@goop.org>
Date:	Thu, 30 Apr 2015 09:39:54 -0700
From:	Jeremy Fitzhardinge <jeremy@...p.org>
To:	Juergen Gross <jgross@...e.com>, linux-kernel@...r.kernel.org,
	x86@...nel.org, hpa@...or.com, tglx@...utronix.de,
	mingo@...hat.com, xen-devel@...ts.xensource.com,
	konrad.wilk@...cle.com, david.vrabel@...rix.com,
	boris.ostrovsky@...cle.com, chrisw@...s-sol.org,
	akataria@...are.com, rusty@...tcorp.com.au,
	virtualization@...ts.linux-foundation.org, gleb@...nel.org,
	pbonzini@...hat.com, kvm@...r.kernel.org
Subject: Re: [PATCH 0/6] x86: reduce paravirtualized spinlock overhead

On 04/30/2015 03:53 AM, Juergen Gross wrote:
> Paravirtualized spinlocks produce some overhead even if the kernel is
> running on bare metal. The main reason are the more complex locking
> and unlocking functions. Especially unlocking is no longer just one
> instruction but so complex that it is no longer inlined.
>
> This patch series addresses this issue by adding two more pvops
> functions to reduce the size of the inlined spinlock functions. When
> running on bare metal unlocking is again basically one instruction.

Out of curiosity, is there a measurable difference?

    J

--
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/