Date: Wed, 1 Jun 2016 20:43:46 +0200 From: Mateusz Guzik <mjguzik@gmail.com> To: John Baldwin <jhb@freebsd.org> Cc: freebsd-current@freebsd.org Subject: Re: [PATCH] microoptimize locking primitives by avoiding unnecessary atomic ops Message-ID: <20160601184346.GA14712@dft-labs.eu> In-Reply-To: <1588845.bSUmdZtqRF@ralph.baldwin.cx> References: <20160527191700.GA23039@dft-labs.eu> <1588845.bSUmdZtqRF@ralph.baldwin.cx>
next in thread | previous in thread | raw e-mail | index | archive | help
On Fri, May 27, 2016 at 04:21:11PM -0700, John Baldwin wrote: > On Friday, May 27, 2016 09:17:01 PM Mateusz Guzik wrote: > > Hello there, > > > > quite some time ago I posted a trivial patch to locking primitives. What > > they do is the inline part tries an atomic op and if that fails the > > actual function is called, which immediately tries the same op. > > > > The obvious optimisation checks for the availability of the lock first. > > > > There concerns about the way it was done previously by relying on > > volatile behaving in a specific way. > > > > Later a simplified version was posted which should not have the concern, > > but the thread died. > > > > I refer you to https://lists.freebsd.org/pipermail/freebsd-current/2015-November/058100.html > > for simple benchmark results. > > > > I would like to get the patch in before 11 freeze. > > I think this looks fine. Thanks for expanding the previous patch to cover > more primitives. > Thanks, committed in https://svnweb.freebsd.org/changeset/base/301157 -- Mateusz Guzik <mjguzik gmail.com>
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20160601184346.GA14712>