From owner-freebsd-arm@freebsd.org Sun Dec 27 22:00:52 2015 Return-Path: Delivered-To: freebsd-arm@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id A5EBAA529EE for ; Sun, 27 Dec 2015 22:00:52 +0000 (UTC) (envelope-from hps@selasky.org) Received: from mail.turbocat.net (heidi.turbocat.net [88.198.202.214]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 708C11A92 for ; Sun, 27 Dec 2015 22:00:51 +0000 (UTC) (envelope-from hps@selasky.org) Received: from laptop015.home.selasky.org (unknown [62.141.129.119]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.turbocat.net (Postfix) with ESMTPSA id 6768D1FE024; Sun, 27 Dec 2015 23:00:42 +0100 (CET) Subject: Re: fyi: 11.0-current rpi2 systat -vmstat shows around 24k interrupts for bcm283x_dw To: Mark Millard , freebsd-arm References: <0A781C7D-C5F5-4931-AE38-D2FEC0848DCA@dsl-only.net> From: Hans Petter Selasky Message-ID: <56806007.2000302@selasky.org> Date: Sun, 27 Dec 2015 23:02:47 +0100 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: <0A781C7D-C5F5-4931-AE38-D2FEC0848DCA@dsl-only.net> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 27 Dec 2015 22:00:52 -0000 On 12/26/15 21:51, Mark Millard wrote: > Context: > >> # freebsd-version -ku; uname -aKU >> 11.0-CURRENT >> 11.0-CURRENT >> FreeBSD rpi2 11.0-CURRENT FreeBSD 11.0-CURRENT #2 r292413M: Fri Dec 25 18:03:19 PST 2015 root@FreeBSDx64:/usr/obj/clang/arm.armv6/usr/src/sys/RPI2-NODBG arm 1100091 1100091 > > > For a basically near-idle context systat -vmstat lists "Int" and 23k to 25k normally (almost always 24k) and bcm283x_dw at the right shows figures like 24118. "generic_ti" is more like 232 and "ipi 76" is more like 111. The others at the right are normally blank (other than total). > > Lots of bcm283x_dw interrupts if around 24k is correct. As the numbers do not change scale when the systat refresh interval is explicitly scaled, I assume that the figures are per second (or per some other time unit, possibly just for the most recent unit instead of mean). > > I'm not sure it will be readable but the below is a capture of a systat -vmstat display. > Hi, The dwc_otg needs to be served frequently in PIO mode. Your number is expected. We're using fast interrupts for most of this work, so no task-switching is involved and so the CPU consumption remains low. You can disable USB like this: usbconfig -d 0.1 set_config 255 And the interrupts should go down to zero. Re-enable like this: usbconfig -d 0.1 set_config 0 --HPS