From owner-freebsd-hackers Thu Oct 3 06:28:09 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id GAA26105 for hackers-outgoing; Thu, 3 Oct 1996 06:28:09 -0700 (PDT) Received: from mail.crl.com (mail.crl.com [165.113.1.22]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id GAA26100 for ; Thu, 3 Oct 1996 06:28:07 -0700 (PDT) Received: from pat.idt.unit.no by mail.crl.com with SMTP id AA16620 (5.65c/IDA-1.5 for ); Thu, 3 Oct 1996 06:28:20 -0700 Received: from idt.unit.no (hyll.idt.unit.no [129.241.200.3]) by pat.idt.unit.no (8.7.5/8.7.3) with ESMTP id PAA15348; Thu, 3 Oct 1996 15:14:32 +0200 (MET DST) Message-Id: <199610031314.PAA15348@pat.idt.unit.no> To: bde@zeta.org.au Cc: freebsd-hackers@freebsd.org Subject: Re: Interrupt lossage in FreeBSD-current. In-Reply-To: Your message of "Thu, 3 Oct 1996 14:37:08 +1000" References: <199610030437.OAA32243@godzilla.zeta.org.au> X-Mailer: Mew version 1.03 on Emacs 19.31.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Date: Thu, 03 Oct 1996 15:14:31 +0200 From: Tor Egge Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > >But something was causing an RTC interrupt to be lost. I've only > >experienced it while profiling a program (while the RTC interrupt rate > >is 1024 Hz), thus I can only assume that the RTC does not like a > >latency longer than the interval between two RTC interrupts. > > Please check this. Disable interrupts for a second or two and see if > the RTC stops. Inserting an INTRDIS(IRQ8) in the load part of an lkm, and an INTREN(IRQ8) in the unload part showed that RTC interrupts stopped while the device was loaded, but resumed as soon as the device was unloaded. Inserting a loop taking 4 seconds while interrupts were disabled in the load part of the lkm just froze the system for 4 seconds, but RTC interrupts resumed afterwards. I no longer see this as a latency issue with regard to the RTC. Something else was causing one RTC interrupt to be lost. - Tor Egge