From owner-freebsd-stable@freebsd.org Tue Feb 16 20:46:53 2016 Return-Path: Delivered-To: freebsd-stable@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 126AFAAB0C0 for ; Tue, 16 Feb 2016 20:46:53 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id E550D15DD for ; Tue, 16 Feb 2016 20:46:52 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: by mailman.ysv.freebsd.org (Postfix) id E15CBAAB0B3; Tue, 16 Feb 2016 20:46:52 +0000 (UTC) Delivered-To: stable@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 C71ECAAB0B0 for ; Tue, 16 Feb 2016 20:46:52 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from mail-io0-x230.google.com (mail-io0-x230.google.com [IPv6:2607:f8b0:4001:c06::230]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 78EA115DC for ; Tue, 16 Feb 2016 20:46:52 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: by mail-io0-x230.google.com with SMTP id z135so138517927iof.0 for ; Tue, 16 Feb 2016 12:46:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=4kCwtcVXdj5sKEiQH4gRgWsaOXva8z9ce5HNWwPlibo=; b=KMWqZxj1mLdf4rq2Ut49irBrBpn5QpF3WzHz1p58zUTQ4oAxNLp+O7bZVSD4OukWAb 2yWNLGSkv2uFbqSP0ZkLGsAvUtqAZSpTqoERjFX4csnJCK/pLOcFWpXH9kCg1fnit1SG ELE55Uw5beAohrbOnK5fiUI+pRZsZ9BhLL8AuiwA6FxukVIx6ONDp2SLuYIWysYgwDhp x6grMyX1EAt76C4clWUYtA3gJMHGmsMvQrTLRaESGaZPtImyBxel7olg5Mq7DPFZMDM5 3UmHjf3WS0N8cZje4ENpQwIsub7EwXO5VKRndsr4RQoyRhdh32mxcKBKRBeewB2EAxs1 wm+g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=4kCwtcVXdj5sKEiQH4gRgWsaOXva8z9ce5HNWwPlibo=; b=OFfC5NS23YsqsF9Yr4jEg+MD/sLgIGfsmIpDllSbPIaASkcKLj411kvQPp+ScMpkrd ODewcx595Nv4wyPcIO8wAd9bfIpjk4FQ81RveoYEKmsfX/AqA9OIMeuzXXwLFitC/pjN TZrxWy+yATb7wWeMRLaDbqkTuPwfbax/8OXTfqMv0C56InYDtkUubkR3GATTA+Zgi0Zs 2Aer3Kl7tLjIwIYK4/Ob5BhMo670A0mcmJ9qrIwrslCfkVXKoaWNNsesPzAIocKkIHfz u25GaA4S28hWGcX608k37N+MGbd82OBdLmyIH+fG1dVra+1tDR+asdv3yV85SvEFTcZU Tt0g== X-Gm-Message-State: AG10YOT+Eg2ISwjBBhXGMSj07LlrAcIheWXHbNfrcnHH4Y0BV0eUA6wZYa8mF9CqyvmFhGAZvf28PkqVSXxONw== MIME-Version: 1.0 X-Received: by 10.107.162.144 with SMTP id l138mr12396336ioe.123.1455655611880; Tue, 16 Feb 2016 12:46:51 -0800 (PST) Received: by 10.36.14.19 with HTTP; Tue, 16 Feb 2016 12:46:51 -0800 (PST) In-Reply-To: <20160216103028.GG68298@zxy.spb.ru> References: <20160210115937.GA37895@zxy.spb.ru> <56BB3C20.600@iet.unipi.it> <20160210135318.GL68298@zxy.spb.ru> <56BC505F.7080309@iet.unipi.it> <20160211133428.GM68298@zxy.spb.ru> <56C1EA66.807@iet.unipi.it> <20160215151318.GQ68298@zxy.spb.ru> <56C1F69C.5010004@iet.unipi.it> <20160215214446.GE68298@zxy.spb.ru> <56C2F898.2010203@iet.unipi.it> <20160216103028.GG68298@zxy.spb.ru> Date: Tue, 16 Feb 2016 12:46:51 -0800 Message-ID: Subject: Re: 82576 + NETMAP + VLAN From: Adrian Chadd To: Slawa Olhovchenkov Cc: Giuseppe Lettieri , Luigi Rizzo , "stable@freebsd.org" Content-Type: text/plain; charset=UTF-8 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 16 Feb 2016 20:46:53 -0000 hi, please bug me in a couple weeks. still moving house, etc. -a On 16 February 2016 at 02:30, Slawa Olhovchenkov wrote: > On Tue, Feb 16, 2016 at 11:23:20AM +0100, Giuseppe Lettieri wrote: > >> I am sorry, I did not participate to the implementation of kqueue >> support and I am not able to comment. Luigi and Adrian should know, however. > > Thanks! > >> Cheers, >> Giuseppe >> >> Il 15/02/2016 22:44, Slawa Olhovchenkov ha scritto: >> > On Mon, Feb 15, 2016 at 05:02:36PM +0100, Giuseppe Lettieri wrote: >> > >> >> Il 15/02/2016 16:13, Slawa Olhovchenkov ha scritto: >> >>> On Mon, Feb 15, 2016 at 04:10:30PM +0100, Giuseppe Lettieri wrote: >> >>> >> >>>> Hi Slawa, >> >>>> >> >>>> I think WITNESS is seeing a false positive, since those two are always >> >>>> different mutexes. >> >>>> >> >>>> The actual deadlock you experience should be caused by something else. I >> >>> >> >>> Are you sure? When deadlock occur I am see threads waiting on nm_kn_lock. >> >> >> >> The deadlock I mentioned still involves nm_kn_locks, sorry if I was not >> >> clear about that. I am just saying that we never try to take the same >> >> lock that we already holding. >> >> >> >> Nonetheless, there are indeed problems in the path that WITNESS has >> >> seen. The problem is that pipes have to notify the other end while >> >> called by kevent. kevent holds the nm_kn_lock on the TX src ring and the >> >> notification takes the nm_kn_lock on the RX dst ring. >> > >> > Can you comment other issuses? Is this by design or is this bug? >> > >> > - with kevent sync for transmiting need first register >> > EVFILT_WRITE/EV_DISABLE and after every write >> > EVFILT_WRITE/EV_DISPATCH >> > >> > - with kevent sync all opening /dev/netmap and registering need do >> > from same thread as kevent using for sinc (unless no RX/TX). >> > >> > >> >> >> -- >> Dr. Ing. Giuseppe Lettieri >> Dipartimento di Ingegneria della Informazione >> Universita' di Pisa >> Largo Lucio Lazzarino 1, 56122 Pisa - Italy >> Ph. : (+39) 050-2217.649 (direct) .599 (switch) >> Fax : (+39) 050-2217.600 >> e-mail: g.lettieri@iet.unipi.it