Date: Wed, 13 Jun 2007 10:14:44 -0700 From: "Kip Macy" <kip.macy@gmail.com> To: "Bruce Evans" <brde@optusnet.com.au>, "Bruce Evans" <bde@freebsd.org>, src-committers@freebsd.org, cvs-src@freebsd.org, cvs-all@freebsd.org Subject: Re: cvs commit: src/sys/libkern mcount.c Message-ID: <b1fa29170706131014t6a9a3d20t228efbfc17b97483@mail.gmail.com> In-Reply-To: <20070613184656.N25269@delplex.bde.org> References: <200706130617.l5D6HncF038605@repoman.freebsd.org> <b1fa29170706122337y558ca741k273e4babb78c936d@mail.gmail.com> <20070613184656.N25269@delplex.bde.org>
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- Original message -
No. It's unlikely that you even configure profiling. Bruce
ROTFL. In that case what does 'config -pp' do? And why did it print
something to the effect of "profiling configured" on the console? And
why did the hang go away when I re-built without '-pp'?
Never mind. I'll just take the time to update the hwpmc support for my
hardware. "hwpmc" also doesn't cause a 50% slowdown when in use.
-Kip
On 6/13/07, Bruce Evans <brde@optusnet.com.au> wrote:
> On Tue, 12 Jun 2007, Kip Macy wrote:
>
> > On 6/12/07, Bruce Evans <bde@freebsd.org> wrote:
> >> bde 2007-06-13 06:17:48 UTC
> >>
> >> FreeBSD src repository
> >>
> >> Modified files:
> >> sys/libkern mcount.c
> >> Log:
> >> Unbreak high resolution profiling a little: use dummy asms to prevent
> >> timing loops being optimized away.
> >>
> >> Once apon a time, gcc promised not to optimize away timing loops, but
> >> gcc started optimizing away the call to a null function in the timing
> >> loop here some time between gcc-3.3.3 and gcc-3.4.6, and it started
> >> optimizing away the timing loop itself some time between gcc-3.4.6
> >> and gcc-4.2.
> >
> > Will this fix the hang on boot that I saw earlier today?
>
> No. It's unlikely that you even configure profiling.
>
> Bruce
>
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