From owner-freebsd-smp Thu Sep 7 17:23:32 2000 Delivered-To: freebsd-smp@freebsd.org Received: from wantadilla.lemis.com (wantadilla.lemis.com [192.109.197.80]) by hub.freebsd.org (Postfix) with ESMTP id 602E937B422; Thu, 7 Sep 2000 17:23:25 -0700 (PDT) Received: (from grog@localhost) by wantadilla.lemis.com (8.11.0/8.9.3) id e880MsN95987; Fri, 8 Sep 2000 09:52:54 +0930 (CST) (envelope-from grog) Date: Fri, 8 Sep 2000 09:52:54 +0930 From: Greg Lehey To: Chuck Paterson Cc: Warner Losh , The Hermit Hacker , freebsd-current@FreeBSD.ORG, freebsd-smp@FreeBSD.ORG Subject: Re: 'interrupt-level buffer overflows' for sio device? Message-ID: <20000908095254.E83632@wantadilla.lemis.com> References: <200009072300.RAA24702@berserker.bsdi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: <200009072300.RAA24702@berserker.bsdi.com>; from cp@bsdi.com on Thu, Sep 07, 2000 at 05:00:15PM -0600 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-smp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Thursday, 7 September 2000 at 17:00:15 -0600, Chuck Paterson wrote: > FYI, this is very likely not caused by the heavy weight > interrupt threads, but rather because the interrupt threads can't > be run because the giant lock is held by a process running in the > kernel. Once we get drivers to have their own locking and pulled out > from under the giant lock this problem should deminish greatly. Before > we can do this there are various infrastructure pieces which must > be made mp safe, such as the lockmanger. We're running sio as a fast interrupt, so it's definitely not because of a heavyweight thread :-) I think fast interrupts also completely bypass mutexes, though something might have changed since I last looked. 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-smp" in the body of the message