From owner-freebsd-arch Tue Jul 18 21:22:12 2000 Delivered-To: freebsd-arch@freebsd.org Received: from wantadilla.lemis.com (wantadilla.lemis.com [192.109.197.80]) by hub.freebsd.org (Postfix) with ESMTP id 8194337B99B; Tue, 18 Jul 2000 21:22:06 -0700 (PDT) (envelope-from grog@wantadilla.lemis.com) Received: (from grog@localhost) by wantadilla.lemis.com (8.9.3/8.9.3) id NAA27189; Wed, 19 Jul 2000 13:51:50 +0930 (CST) (envelope-from grog) Date: Wed, 19 Jul 2000 13:51:49 +0930 From: Greg Lehey To: Chuck Paterson Cc: Warner Losh , arch@freebsd.org, smp@freebsd.org Subject: Re: Tidying up the interrupt registration process Message-ID: <20000719135149.I12072@wantadilla.lemis.com> References: <200007190358.VAA09445@berserker.bsdi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0pre2i In-Reply-To: <200007190358.VAA09445@berserker.bsdi.com> Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-418-838-708 WWW-Home-Page: http://www.lemis.com/~grog X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Tuesday, 18 July 2000 at 21:58:57 -0600, Chuck Paterson wrote: > > }That's what I thought. Does anybody else see a reason to convert fast > }interrupts into threads? > > The short answer is no, you absolutely don't want to > convert them to fully instantiated threads, especially when you > only have a heavy wait solution. There is another middle ground > that is less clear, and it depends partially on what you deem a > thread. If you just switch the stack pointer and curproc, but use > spin locks and don't allow for a context switch are you converting > it to a thread. At this point the statistical stuff will charge > time properly to interrupts rather than user processes, or other > kernel processes, you also don't have to worry about pathological > cases blowing out the stack. Does BSD/OS have fast interrupts? I haven't seen any evidence. In FreeBSD, a fast interrupt runs before EOI, so we can't convert it to a thread. Greg -- Finger grog@lemis.com for PGP public key See complete headers for address and phone numbers To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message