From owner-svn-src-head@freebsd.org Fri Apr 14 21:21:06 2017 Return-Path: Delivered-To: svn-src-head@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 C22ACD3EBC3 for ; Fri, 14 Apr 2017 21:21:06 +0000 (UTC) (envelope-from sobomax@sippysoft.com) Received: from mail-it0-x230.google.com (mail-it0-x230.google.com [IPv6:2607:f8b0:4001:c0b::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 90D39E1A for ; Fri, 14 Apr 2017 21:21:06 +0000 (UTC) (envelope-from sobomax@sippysoft.com) Received: by mail-it0-x230.google.com with SMTP id b15so1235249iti.1 for ; Fri, 14 Apr 2017 14:21:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sippysoft-com.20150623.gappssmtp.com; s=20150623; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=Lt6woQbb8f2svgqmCXk3kRKPVnCzTbs8xRXehv558k4=; b=t8zzk+y3HvFTfLvluYbi++ati550vbrgc6oxxVVvUKcn7+83f1/aYBuZ3uWDUYRcQa IlqJJL0i/DuxPdipAMHGzHYhxp91J+8x9BU54z3JqckbOYC91RJ7k6rd7P3MM9n7X8rU 9GVIxGq/3BBVomSAk56SgHcpN59gyHwIPTCgXsmVtmuaEq1Kd6tddY9c4n6LbOmEJI2Z kraVhcLIL43ylIvTY7HmKd79US60ilbLBIaqlWCzHYL7iDvTLeUqDeoh5hwNUORxXXR6 pAVq2g8O4vIR3VW5MUJGa88NY/dYrYEA0DPxsmvvoF92b2qch4JBTfHiLu7nLGGa4Mo+ 8mCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc; bh=Lt6woQbb8f2svgqmCXk3kRKPVnCzTbs8xRXehv558k4=; b=qrGmUwT9zW8CMsbiaL6Yq1rTL11TJNlPm13xyu4jOvJpOHZC0i0/pZgf/DbRSPDnul nX619DIjKijQQzVYccg5XVX0K5oQhQyW2+HM1w9VVo5jME+mTgNIhnQ4k2fg6ymGP5w0 Eh8qYJWFsTt4meYarq3JvgVpFeAlf54j+ZhsvuLC59V5rP2BS0dHdMc528X4k5suJGo1 uP6iVm+e4ewxwrfdCCmP/cm4qnUqWmeScqbVE7NfJIy9uvzV+Y/L3Bp1+3gBmJ0MJfhB +aow0Gr6JPK2SMVzayIQ071X3voNe5A79vSWNw+PLq+FYNqeRRpGL+j3iGtAG7h2Azzu VyGA== X-Gm-Message-State: AN3rC/6n+oniOdzkygiKtaxwCj3BavESxlFXrB6+VK9wv0llYu6O/AGd TBos1U+IQfIShEX7YvjklemoLeS5vngyZmk= X-Received: by 10.36.10.129 with SMTP id 123mr632176itw.80.1492204865866; Fri, 14 Apr 2017 14:21:05 -0700 (PDT) MIME-Version: 1.0 Sender: sobomax@sippysoft.com Received: by 10.36.104.135 with HTTP; Fri, 14 Apr 2017 14:21:05 -0700 (PDT) In-Reply-To: <6942092.OsECkgAp13@overcee.wemm.org> References: <201704141723.v3EHNS3B043902@repo.freebsd.org> <12133324.zHp9vo75vZ@overcee.wemm.org> <6942092.OsECkgAp13@overcee.wemm.org> From: Maxim Sobolev Date: Fri, 14 Apr 2017 14:21:05 -0700 X-Google-Sender-Auth: kV0jSDJWo39zLMRQyxdbuopta60 Message-ID: Subject: Re: svn commit: r316874 - head/sys/kern To: Peter Wemm Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers , Hiren Panchasara Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.23 X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Apr 2017 21:21:06 -0000 Peter, It is actually the other way around. If you take syslogd code out of 11-stable and earlier that would work just fine with or without r316874. But since r285910 syslogd in head had been refactored a lot and I think that particular bug has introduced that has been masked by the shutdown() on datagram sockets becoming a NOP after r285910. Then r316874 restored our historical behavior for the shutdown(2) and bingo, bug in the new syslogd code is now causing it to spin when shutdown() != NOP. -Max On Fri, Apr 14, 2017 at 12:46 PM, Peter Wemm wrote: > On Friday, April 14, 2017 12:41:52 PM Maxim Sobolev wrote: > > Thanks, Peter. I will try to look into this asap. > > I don't understand what is going on yet. Presumably there must be other > changes in play that affect udp/select sometime between the original 2015 > change and this. The syslogd -s code is Old(TM). I'm also wondering > whether > the -s code even works at all since the 2015 / r285910 change... > > > -Max > > > > On Apr 14, 2017 12:32 PM, "Peter Wemm" wrote: > > > On Friday, April 14, 2017 11:49:26 AM Peter Wemm wrote: > > > > On Friday, April 14, 2017 05:23:28 PM Maxim Sobolev wrote: > > > > > Author: sobomax > > > > > Date: Fri Apr 14 17:23:28 2017 > > > > > New Revision: 316874 > > > > > URL: https://svnweb.freebsd.org/changeset/base/316874 > > > > > > > > > > Log: > > > > > Restore ability to shutdown DGRAM sockets, still forcing > ENOTCONN to > > > > > > be > > > > > > > > returned by the shutdown(2) system call. This ability has been > lost as > > > > > part > > > > > of the svn revision 285910. > > > > > > > > > > Reviewed by: ed, rwatson, glebius, hiren > > > > > MFC after: 2 weeks > > > > > Differential Revision: https://reviews.freebsd.org/D10351 > > > > > > > > This appears to have broken syslogd and had a major change in > behavior > > > > > > with > > > > > > > regards to select(2). > > > > > > > > If you run syslogd with the -s flag (which is default), it now spins > at > > > > > > 100% > > > > > > > cpu as all the shutdown sockets now return readable from select. > > > > > > > > Old releases / jails also manifest this behavor. If it wasn't for > > > > losing > > > > the ability to run old branch binaries I'd suggest changing syslogd > > > > instead, but we depend on this in the cluster and I expect others do > > > > too. > > > > > > > > I'm not 100% certain that this change is the culprit but a heads-up > > > > can't > > > > hurt. I'll try reverting it on the freebsd cluster next, after fixing > > > > the > > > > broken auditing changes. > > > > > > > > -Peter > > > > > > I can confirm that reverting r316874 fixes syslogd and backwards > > > compatability > > > with old branches. > > > > > > -- > > > Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com; > > > KI6FJV > > > UTF-8: for when a ' or ... just won\342\200\231t do\342\200\246 > > -- > Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com; > KI6FJV > UTF-8: for when a ' or ... just won\342\200\231t do\342\200\246 >