From owner-freebsd-hackers Mon Jan 22 12:50:27 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from rjlhome.sco.com (unknown [207.65.180.181]) by hub.freebsd.org (Postfix) with ESMTP id B2A5A37B698 for ; Mon, 22 Jan 2001 12:50:08 -0800 (PST) Received: by rjlhome.sco.com (8.9.3/SCO5) id OAA12347; Mon, 22 Jan 2001 14:55:50 -0600 (CST) Date: Mon, 22 Jan 2001 14:55:50 -0600 From: Robert Lipe To: Alfred Perlstein Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: contigmalloc, M_WAITOK, & leaks. Message-ID: <20010122145550.O10504@rjlhome.sco.com> References: <20010122110642.B10504@rjlhome.sco.com> <20010122100524.D7240@fw.wintelcom.net> <20010122124539.F10504@rjlhome.sco.com> <20010122105227.E7240@fw.wintelcom.net> <20010122132647.I10504@rjlhome.sco.com> <20010122121033.A26076@fw.wintelcom.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.4i In-Reply-To: <20010122121033.A26076@fw.wintelcom.net>; from bright@wintelcom.net on Mon, Jan 22, 2001 at 12:10:33PM -0800 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Alfred Perlstein wrote: > > So if I sandbagged the allocs to be *larger* the KMA would behave more > > consistently with what I'd expect becuase it would then reclaim? I > > didn't see that one coming. :-) > > but... this is a terrible workaround, I'm not sure it would work > and you shouldn't do it. :) Good. I didn't actully *want* to do that. I still have to respect myself in the morning. :-) > > Is there an s/g memory interface in FreeBSD? This was my first choice, > > See the busdma stuff, Yes, this looks to be much closer to the interface I really wanted anyway. I see no man pages for them. Is there any doc anywhere? "Read the source and look at existing examples" will do if it must but any pointers to better doc are appreciated. > there's a problem because there's no busdma > for mbufs (well actually there is but it fails on really small > unaligned blocks which basically breaks it for mbufs). Can you tell me more about this hazard? I can't control the alignment that's asked for by the driver, but I can certainly fudge the size and alignment of the request by the time it gets to this interface. Just tell me the rules. :-) > ack, I'd review patches if you wanted to write/port busdma for mbufs.. Thanx for the offer, but I'm hoping to avoid that right now. It's very much a goal of mine (esp. now that we're in the final days of the NDA requirement) to stamp out something that works on shipping FreeBSD well enough for this crowd to see what remains to be done and see where we are. Then we can figure out how to improve interfaces or otherwise enhance the base OS if we want to. So given a choice between, say, incurring an extra copy in a data path and porting busdma for mbufs I'll take the former for now. RJL To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message