From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Mosberger Date: Fri, 04 Jun 2004 14:52:40 +0000 Subject: Re: sched_clock - cont'd Message-Id: <16576.36024.383196.931650@napali.hpl.hp.com> List-Id: References: <40C08A29.A46DF067@nospam.org> In-Reply-To: <40C08A29.A46DF067@nospam.org> MIME-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable To: linux-ia64@vger.kernel.org >>>>> On Fri, 04 Jun 2004 16:41:45 +0200, Zoltan Menyhart said: Zoltan> Oops: timer tick before it's due Zoltan> (itc=9859824596,itm=985985c2ef) Oops: timer tick before it's Zoltan> due (itc=9859f75936,itm=9859f9ac37) Oops: timer tick before Zoltan> it's due (itc=985a6c6c40,itm=985a6d957f) CPU 3: synchronized Zoltan> ITC with CPU 0 (last diff -3 cycles, maxerr 494 cycles) Zoltan> Once it is over, everything seems to be correct. E.g. I can Zoltan> stress the system by compiling the kernel with "make -j100". Zoltan> It's a 2.6.5 kernel. I'm sure the new "sched_clock" code is Zoltan> O.K. I guess this modification has brought to light a hidden Zoltan> bug in the initial CPU synchronization or timing set up Zoltan> code. Have you ever seen a similar problem ? No. sched_clock() has nothing to do with the timer-tick or time-of-day, so the problem must be something else. --david