Date: Wed, 4 Nov 2009 17:15:28 +0100 From: Attilio Rao <attilio@freebsd.org> To: =?UTF-8?Q?Dag=2DErling_Sm=C3=B8rgrav?= <des@des.no> Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r198868 - in head/sys: amd64/amd64 i386/i386 Message-ID: <3bbf2fe10911040815u780ea5d5h8252b46ddf0c5de7@mail.gmail.com> In-Reply-To: <86y6mmff1a.fsf@ds4.des.no> References: <200911040132.nA41WxtQ012750@svn.freebsd.org> <863a4ugvmi.fsf@ds4.des.no> <3bbf2fe10911040806l7293ab6l99cce51ea9d7a64c@mail.gmail.com> <86y6mmff1a.fsf@ds4.des.no>
next in thread | previous in thread | raw e-mail | index | archive | help
2009/11/4, Dag-Erling Sm=C3=B8rgrav <des@des.no>: > Attilio Rao <attilio@freebsd.org> writes: > > Dag-Erling Sm=C3=B8rgrav <des@des.no> writes: > > > According to the reference you gave, OpenSolaris has a workaround for > > > this issue. Perhaps we should adopt it? > > IIRC, based on what I readed on-line, it could be still a WARNING msg, > > but I didn't double-check for it. > > Uh, apparently, it can be worked around with an additional lfence > instruction... See the first couple of comments on that bugzilla page > you linked to. If the cost is too high, we could make it conditional on > "options BROKEN_OPTERON_E" or something. Yeah but the lfence is completely impratical from the overhead POV -- and actually I don't like the idea to add a compile time option based on family/model. We could maybe do a mixed approach: printout the WARNING msg only if the BROKEN_OPTERON_E is not used otherwise be ok. I still don't like it because it is going to dirty the atomic.h code a bit, but it can be an acceptable compromise. Attilio --=20 Peace can only be achieved by understanding - A. Einstein
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3bbf2fe10911040815u780ea5d5h8252b46ddf0c5de7>