From owner-svn-src-head@freebsd.org Wed Feb 21 15:18:24 2018 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 0AFDAF0B4BD; Wed, 21 Feb 2018 15:18:24 +0000 (UTC) (envelope-from andrew@fubar.geek.nz) Received: from fry.fubar.geek.nz (fry.fubar.geek.nz [139.59.165.16]) by mx1.freebsd.org (Postfix) with ESMTP id A23448105D; Wed, 21 Feb 2018 15:18:23 +0000 (UTC) (envelope-from andrew@fubar.geek.nz) Received: from [IPv6:2001:630:212:2a8:5c38:d7dc:2091:57b5] (unknown [IPv6:2001:630:212:2a8:5c38:d7dc:2091:57b5]) by fry.fubar.geek.nz (Postfix) with ESMTPSA id 9582B4EBEA; Wed, 21 Feb 2018 15:11:14 +0000 (UTC) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 11.2 \(3445.5.20\)) Subject: Re: svn commit: r329612 - in head/sys: kern sys From: Andrew Turner In-Reply-To: <201802200006.w1K067ZL032311@repo.freebsd.org> Date: Wed, 21 Feb 2018 15:11:13 +0000 Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Content-Transfer-Encoding: quoted-printable Message-Id: References: <201802200006.w1K067ZL032311@repo.freebsd.org> To: Jeff Roberson X-Mailer: Apple Mail (2.3445.5.20) 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, 21 Feb 2018 15:18:24 -0000 > On 20 Feb 2018, at 00:06, Jeff Roberson wrote: >=20 > Author: jeff > Date: Tue Feb 20 00:06:07 2018 > New Revision: 329612 > URL: https://svnweb.freebsd.org/changeset/base/329612 >=20 > Log: > Further parallelize the buffer cache. >=20 > Provide multiple clean queues partitioned into 'domains'. Each = domain manages > its own bufspace and has its own bufspace daemon. Each domain has a = set of > subqueues indexed by the current cpuid to reduce lock contention on = the cleanq. >=20 > Refine the sleep/wakeup around the bufspace daemon to use atomics as = much as > possible. >=20 > Add a B_REUSE flag that is used to requeue bufs during the scan to = approximate > LRU rather than locking the queue on every use of a frequently = accessed buf. >=20 > Implement bufspace_reserve with only atomic_fetchadd to avoid loop = restarts. >=20 > Reviewed by: markj > Tested by: pho > Sponsored by: Netflix, Dell/EMC Isilon > Differential Revision: https://reviews.freebsd.org/D14274 I=E2=80=99m seeing the following panic on FreeBSD/arm64 after this = change. Andrew panic: bq_remove: Remove buffer 0xffff00004082f260 from wrong queue. cpuid =3D 4 time =3D 1519088201 KDB: stack backtrace: db_trace_self() at db_trace_self_wrapper+0x28 pc =3D 0xffff00000062fee4 lr =3D 0xffff0000000c0450 sp =3D 0xffff000040364480 fp =3D 0xffff000040364690 db_trace_self_wrapper() at vpanic+0x184 pc =3D 0xffff0000000c0450 lr =3D 0xffff000000354ce8 sp =3D 0xffff0000403646a0 fp =3D 0xffff000040364720 vpanic() at kassert_panic+0x158 pc =3D 0xffff000000354ce8 lr =3D 0xffff000000354b60 sp =3D 0xffff000040364730 fp =3D 0xffff0000403647f0 kassert_panic() at bq_remove+0x178 pc =3D 0xffff000000354b60 lr =3D 0xffff0000003f7014 sp =3D 0xffff000040364800 fp =3D 0xffff000040364810 bq_remove() at buf_recycle+0x100 pc =3D 0xffff0000003f7014 lr =3D 0xffff0000003fca80 sp =3D 0xffff000040364820 fp =3D 0xffff000040364880 buf_recycle() at bufspace_daemon+0xb4 pc =3D 0xffff0000003fca80 lr =3D 0xffff0000003fd31c sp =3D 0xffff000040364890 fp =3D 0xffff000040364910 bufspace_daemon() at fork_exit+0x7c pc =3D 0xffff0000003fd31c lr =3D 0xffff000000318388 sp =3D 0xffff000040364920 fp =3D 0xffff000040364950 fork_exit() at fork_trampoline+0x10 pc =3D 0xffff000000318388 lr =3D 0xffff000000649ec4 sp =3D 0xffff000040364960 fp =3D 0x0000000000000000 KDB: enter: panic=