linux-kernel - Re: [PATCH 00/13] [PATCH RFC] Paravirtualized ticketlocks

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: <CA+55aFy8p5-q9cNfyWz1bFT4RKxZosyHM2t5g2miiWm2DvP1Gg@mail.gmail.com>
Date:	Fri, 2 Sep 2011 13:27:44 -0700
From:	Linus Torvalds <torvalds@...ux-foundation.org>
To:	Jeremy Fitzhardinge <jeremy@...p.org>
Cc:	"H. Peter Anvin" <hpa@...or.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...e.hu>,
	"the arch/x86 maintainers" <x86@...nel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Nick Piggin <npiggin@...nel.dk>, Avi Kivity <avi@...hat.com>,
	Marcelo Tosatti <mtosatti@...hat.com>,
	KVM <kvm@...r.kernel.org>, Andi Kleen <andi@...stfloor.org>,
	Xen Devel <xen-devel@...ts.xensource.com>,
	Jeremy Fitzhardinge <jeremy.fitzhardinge@...rix.com>
Subject: Re: [PATCH 00/13] [PATCH RFC] Paravirtualized ticketlocks

On Fri, Sep 2, 2011 at 1:07 PM, Jeremy Fitzhardinge <jeremy@...p.org> wrote:
>
> I don't know whether that fastpath code is small enough to consider
> inlining everywhere?

No.

There's no point in inlining something that ends up containing a
conditional function call: gcc will have to effectively save/restore
registers around that thing anyway, so you lose a lot of the
advantages of inlining. So I think it's better done as an out-of-line
function, which I thought we did for spinlocks anyway.

Also, do you run with CONFIG_OPTIMIZE_SIZE? Without that, gcc should
be smart enough to make a "likely()" case be a fall-through.

                          Linus
--
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/