From owner-freebsd-current@FreeBSD.ORG Fri Jun 26 12:46:41 2009 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id AC6771065672 for ; Fri, 26 Jun 2009 12:46:41 +0000 (UTC) (envelope-from stas@FreeBSD.org) Received: from mx0.deglitch.com (backbone.deglitch.com [IPv6:2001:16d8:fffb:4::abba]) by mx1.freebsd.org (Postfix) with ESMTP id 36EE68FC18 for ; Fri, 26 Jun 2009 12:46:41 +0000 (UTC) (envelope-from stas@FreeBSD.org) Received: from stasss.yandex.ru (dhcp170-227-red.yandex.net [95.108.170.227]) by mx0.deglitch.com (Postfix) with ESMTPSA id 3E5EC8FC45; Fri, 26 Jun 2009 16:46:39 +0400 (MSD) Date: Fri, 26 Jun 2009 16:46:39 +0400 From: Stanislav Sedov To: Thomas Backman Message-Id: <20090626164639.71a34f62.stas@FreeBSD.org> In-Reply-To: <993B7B5B-1B6B-48A5-8425-6A1D071335A9@exscape.org> References: <993B7B5B-1B6B-48A5-8425-6A1D071335A9@exscape.org> Organization: The FreeBSD Project X-Mailer: carrier-pigeon Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: freebsd-current@freebsd.org, Artem Belevich Subject: Re: ZFS : panic("sleeping thread") X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 Jun 2009 12:46:41 -0000 On Thu, 18 Jun 2009 13:49:46 +0200 Thomas Backman mentioned: > Anyone have any updates on this? I just got a "sleeping thread" panic > in ZFS after doing a zfs rollback. Unfortunately, "panic" in the > debugger resulted in "dump device too small" (despite being RAM-sized) > so I don't have a BT... However the BT I got in the debugger was *not* > the same as yours. There was no _sx_xlock in it, but that's pretty > much all I know about it. :( > Hi, Thomas! Can you, please, try with the following patch? Thanks! --------------------------------------------------------------------------- diff -r a707b4dd87cf src/sys/kern/kern_event.c --- a/src/sys/kern/kern_event.c Fri Jun 26 13:49:09 2009 +0400 +++ b/src/sys/kern/kern_event.c Fri Jun 26 16:45:15 2009 +0400 @@ -1608,7 +1608,7 @@ * first. */ void -knote(struct knlist *list, long hint, int islocked) +knote(struct knlist *list, long hint, int lockflags) { struct kqueue *kq; struct knote *kn; @@ -1617,9 +1617,9 @@ if (list == NULL) return; - KNL_ASSERT_LOCK(list, islocked); + KNL_ASSERT_LOCK(list, lockflags & KNF_LISTLOCKED); - if (!islocked) + if ((lockflags & KNF_LISTLOCKED) == 0) list->kl_lock(list->kl_lockarg); /* @@ -1636,7 +1636,7 @@ KQ_LOCK(kq); if ((kn->kn_status & KN_INFLUX) == KN_INFLUX) { KQ_UNLOCK(kq); - } else { + } else if ((lockflags & KNF_NOKQLOCK) != 0) { kn->kn_status |= KN_INFLUX; KQ_UNLOCK(kq); error = kn->kn_fop->f_event(kn, hint); @@ -1645,11 +1645,17 @@ if (error) KNOTE_ACTIVATE(kn, 1); KQ_UNLOCK_FLUX(kq); + } else { + kn->kn_status |= KN_HASKQLOCK; + if (kn->kn_fop->f_event(kn, hint)) + KNOTE_ACTIVATE(kn, 1); + kn->kn_status &= ~KN_HASKQLOCK; + KQ_UNLOCK(kq); } } kq = NULL; } - if (!islocked) + if ((lockflags & KNF_LISTLOCKED) == 0) list->kl_unlock(list->kl_lockarg); } diff -r a707b4dd87cf src/sys/sys/event.h --- a/src/sys/sys/event.h Fri Jun 26 13:49:09 2009 +0400 +++ b/src/sys/sys/event.h Fri Jun 26 16:45:15 2009 +0400 @@ -135,8 +135,14 @@ MALLOC_DECLARE(M_KQUEUE); #endif -#define KNOTE(list, hist, lock) knote(list, hist, lock) -#define KNOTE_LOCKED(list, hint) knote(list, hint, 1) +/* + * Flags for knote call + */ +#define KNF_LISTLOCKED 0x0001 /* knlist is locked */ +#define KNF_NOKQLOCK 0x0002 /* do not keep KQ_LOCK */ + +#define KNOTE(list, hist, flags) knote(list, hist, flags) +#define KNOTE_LOCKED(list, hint) knote(list, hint, KNF_LISTLOCKED) #define KNOTE_UNLOCKED(list, hint) knote(list, hint, 0) #define KNLIST_EMPTY(list) SLIST_EMPTY(&(list)->kl_list) @@ -204,7 +210,7 @@ struct proc; struct knlist; -extern void knote(struct knlist *list, long hint, int islocked); +extern void knote(struct knlist *list, long hint, int lockflags); extern void knote_fork(struct knlist *list, int pid); extern void knlist_add(struct knlist *knl, struct knote *kn, int islocked); extern void knlist_remove(struct knlist *knl, struct knote *kn, int islocked); diff -r a707b4dd87cf src/sys/sys/mount.h --- a/src/sys/sys/mount.h Fri Jun 26 13:49:09 2009 +0400 +++ b/src/sys/sys/mount.h Fri Jun 26 16:45:15 2009 +0400 @@ -633,7 +633,7 @@ #define VFS_KNOTE_LOCKED(vp, hint) do \ { \ if (((vp)->v_vflag & VV_NOKNOTE) == 0) \ - VN_KNOTE((vp), (hint), 1); \ + VN_KNOTE((vp), (hint), KNF_LISTLOCKED); \ } while (0) #define VFS_KNOTE_UNLOCKED(vp, hint) do \ diff -r a707b4dd87cf src/sys/sys/vnode.h --- a/src/sys/sys/vnode.h Fri Jun 26 13:49:09 2009 +0400 +++ b/src/sys/sys/vnode.h Fri Jun 26 16:45:15 2009 +0400 @@ -222,9 +222,10 @@ #define VN_KNOTE(vp, b, a) \ do { \ if (!VN_KNLIST_EMPTY(vp)) \ - KNOTE(&vp->v_pollinfo->vpi_selinfo.si_note, (b), (a)); \ + KNOTE(&vp->v_pollinfo->vpi_selinfo.si_note, (b), \ + (a) | KNF_NOKQLOCK); \ } while (0) -#define VN_KNOTE_LOCKED(vp, b) VN_KNOTE(vp, b, 1) +#define VN_KNOTE_LOCKED(vp, b) VN_KNOTE(vp, b, KNF_LISTLOCKED) #define VN_KNOTE_UNLOCKED(vp, b) VN_KNOTE(vp, b, 0) /* --------------------------------------------------------------------------------- -- Stanislav Sedov ST4096-RIPE