From owner-svn-src-head@freebsd.org Wed Jan 10 20:38:43 2018 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 91283E758CE for ; Wed, 10 Jan 2018 20:38:43 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: from mail-io0-x235.google.com (mail-io0-x235.google.com [IPv6:2607:f8b0:4001:c06::235]) (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 554A16B276 for ; Wed, 10 Jan 2018 20:38:43 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: by mail-io0-x235.google.com with SMTP id z130so821836ioe.13 for ; Wed, 10 Jan 2018 12:38:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsdimp-com.20150623.gappssmtp.com; s=20150623; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=o+GxQjTiTgITleNCtYMx1lifaM3dDR5D7DFusdwSoMk=; b=EGFP+AmcC/ED63DZlgVspheANBjUNaEZxNvakr9uYA3F7KqKfFpK4YeYJPtFB+8Et1 p1n0NDM2fOoXZUNVSFEyhtluWq5uLJloEbb8ze8mULl1Z7+4irt+SoquEW9+MXxyqqwY wBukZ3n+A82kraCrjlAuAxMCxs0hcyPPaP/oJfkRf7VGLKnv0JM/SL77pPFdnuRYkNmT O64Vj37a8fEu+5/jYPhnPAndF+frGGhkePW0bxJ2HQVKBbnbQao832qOkc6o+gjVLD0s Z9wa9O0cx2JoEbhdPpJKmX/VWKIvlLraOs0lazcJBKscdyV8Pkz6h0IytKOdGAbgNUJu tYxA== 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=o+GxQjTiTgITleNCtYMx1lifaM3dDR5D7DFusdwSoMk=; b=SQsNHsOpeXYjLrbXrwd6xh10W+cz3zkv3sg104Zy9CnFXV98O8Ze+IEPGB0f6RU/K7 l3ZjydcRLSQesPnegBlqRc71pSpMTvfpMwR7ti9HaW0qPDQJtl/ZGV3qYveE5fogczRj FFC4cn3FdOqGeoZWZTpPovymZFeopfevgtLrNQwOlTsBDS+5pwDH1UoKp1X1J2xySyc/ 8XkxVGKsX5xcZNc8mS3z9LnoFfqfyrYIxd+4NSxi5AC9z5tUaovZbJMztkGEOxybD0v0 /UiM5l3Ssdl1yV49qsTN6iwnaHjc/CO6Y30uEJ0kE5JCGkvi3jf0+bHsi3Ta3KZLOZ7y N3zA== X-Gm-Message-State: AKwxytfl0lP/Ym0HOTTqjZz7fyuwcONuDFYGf2bbh3QFy9pGyvWqYd9F /+8C1GW3sMiwaL8KFdPNiJ7ud/fhtX4sYy84Z0Hyyw== X-Google-Smtp-Source: ACJfBouoUN+nCz1vFsGuF16k6JneidFy5TaVvKa7bHPCFBnlWkyuGcwJnh8eGjS/RHj4DjHsSbuy04ClhbYpQ383e4Y= X-Received: by 10.107.78.12 with SMTP id c12mr18638544iob.63.1515616722417; Wed, 10 Jan 2018 12:38:42 -0800 (PST) MIME-Version: 1.0 Sender: wlosh@bsdimp.com Received: by 10.79.160.217 with HTTP; Wed, 10 Jan 2018 12:38:41 -0800 (PST) X-Originating-IP: [2603:300b:6:5100:1052:acc7:f9de:2b6d] In-Reply-To: <20180110203515.GD78524@raichu> References: <201712190413.vBJ4DMY9090982@repo.freebsd.org> <20180110202442.GC78524@raichu> <20180110203515.GD78524@raichu> From: Warner Losh Date: Wed, 10 Jan 2018 13:38:41 -0700 X-Google-Sender-Auth: OBqgHLB2JPLS9WkHQP1QHPnuj5M Message-ID: Subject: Re: svn commit: r326964 - head/sys/cam To: Mark Johnston Cc: Warner Losh , src-committers , svn-src-all@freebsd.org, svn-src-head@freebsd.org Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.25 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: Wed, 10 Jan 2018 20:38:43 -0000 On Wed, Jan 10, 2018 at 1:35 PM, Mark Johnston wrote: > On Wed, Jan 10, 2018 at 01:32:29PM -0700, Warner Losh wrote: > > On Wed, Jan 10, 2018 at 1:24 PM, Mark Johnston > wrote: > > > > > On Tue, Dec 19, 2017 at 04:13:22AM +0000, Warner Losh wrote: > > > > Author: imp > > > > Date: Tue Dec 19 04:13:22 2017 > > > > New Revision: 326964 > > > > URL: https://svnweb.freebsd.org/changeset/base/326964 > > > > > > > > Log: > > > > When doing a dump, the scheduler is normally not running, so this > > > > changed worked to capture dumps for me. However, the test for > > > > SCHEDULER_STOPPED() isn't right. We can also call the dump routine > > > > from ddb, in which case the scheduler is still running. This leads > to > > > > an assertion panic that we're sleeping when we shouldn't. Instead, > use > > > > the proper test for dumping or not. This brings us in line with > other > > > > places that do special things while we're doing polled I/O like > this. > > > > > > > > Noticed by: pho@ > > > > Differential Revision: https://reviews.freebsd.org/D13531 > > > > > > > > Modified: > > > > head/sys/cam/cam_periph.c > > > > > > > > Modified: head/sys/cam/cam_periph.c > > > > ============================================================ > > > ================== > > > > --- head/sys/cam/cam_periph.c Tue Dec 19 04:06:07 2017 > (r326963) > > > > +++ head/sys/cam/cam_periph.c Tue Dec 19 04:13:22 2017 > (r326964) > > > > @@ -38,6 +38,7 @@ __FBSDID("$FreeBSD$"); > > > > #include > > > > #include > > > > #include > > > > +#include > > > > #include > > > > #include > > > > #include > > > > @@ -1158,7 +1159,7 @@ cam_periph_runccb(union ccb *ccb, > > > > struct bintime *starttime; > > > > struct bintime ltime; > > > > int error; > > > > - bool sched_stopped; > > > > + bool must_poll; > > > > struct mtx *periph_mtx; > > > > struct cam_periph *periph; > > > > uint32_t timeout = 1; > > > > @@ -1182,7 +1183,13 @@ cam_periph_runccb(union ccb *ccb, > > > > devstat_start_transaction(ds, starttime); > > > > } > > > > > > > > - sched_stopped = SCHEDULER_STOPPED(); > > > > + /* > > > > + * We must poll the I/O while we're dumping. The scheduler is > > > normally > > > > + * stopped for dumping, except when we call doadump from ddb. > > > While the > > > > + * scheduler is running in this case, we still need to poll the > > > I/O to > > > > + * avoid sleeping waiting for the ccb to complete. > > > > + */ > > > > + must_poll = dumping; > > > > > > Hmm, unfortunately this introduces a new problem: after a panic we call > > > adashutdown() as part of the shutdown_post_sync event. This occurs > > > before we call doadump(), so dumping == 0 and we don't poll for the > > > spindown command's completion. But since we've panicked, the scheduler > > > is stopped, and so we just hang. > > > > > > > So "dumping || SCHEDULER_STOPPED()" then is needed? > > It seems so, unfortunately. > OK. Sounds good. I'll make the change today.