From owner-freebsd-hackers Tue Nov 21 17:46:18 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from chopper.Poohsticks.ORG (chopper.poohsticks.org [63.227.60.73]) by hub.freebsd.org (Postfix) with ESMTP id 6EA4937B479 for ; Tue, 21 Nov 2000 17:46:15 -0800 (PST) Received: from chopper.Poohsticks.ORG (drew@localhost.poohsticks.org [127.0.0.1]) by chopper.Poohsticks.ORG (8.10.1/8.10.1) with ESMTP id eAM1kFh09832 for ; Tue, 21 Nov 2000 18:46:16 -0700 Message-Id: <200011220146.eAM1kFh09832@chopper.Poohsticks.ORG> To: freebsd-hackers@freebsd.org Subject: Interrupt threads MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <9828.974857575.1@chopper.Poohsticks.ORG> Date: Tue, 21 Nov 2000 18:46:15 -0700 From: Drew Eckhardt Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG For reasons beyond my control, I'm stuck using FreeBSD in a real time system and am violating my timing constraints when too many SCSI commands complete in a short time frame and starve one of my userland real time processes. If the interrupt handler wokeup a kernel thread running at a lower real-time priority than my application which disabled the interrupt on the PIC/APIC, ran the handler, and re-enabled the line on the PIC/APIC my problems should go away. -CURRENT supposedly uses threads for interrupts. Is there a more specific description of what it does archived somewhere? Assuming familiarity with the interrupt code and a cursory but improving understanding of the scheduler, how messy would it be to retrofit that code to -stable or 3.1-stable ? -- Home Page For those who do, no explanation is necessary. For those who don't, no explanation is possible. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message