Date: Thu, 11 Aug 2016 22:57:23 +0000 From: Glen Barber <gjb@FreeBSD.org> To: Slawa Olhovchenkov <slw@zxy.spb.ru> Cc: Andriy Gapon <avg@FreeBSD.org>, src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: Re: svn commit: r303970 - in stable/11/sys/cddl: compat/opensolaris/sys contrib/opensolaris/uts/common/fs/zfs contrib/opensolaris/uts/common/fs/zfs/sys Message-ID: <20160811225723.GG51184@FreeBSD.org> In-Reply-To: <20160811225202.GI8192@zxy.spb.ru> References: <201608112048.u7BKm4OH076291@repo.freebsd.org> <20160811223331.GF22212@zxy.spb.ru> <20160811223637.GE51184@FreeBSD.org> <20160811225202.GI8192@zxy.spb.ru>
next in thread | previous in thread | raw e-mail | index | archive | help
--8bBEDOJVaa9YlTAt Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Aug 12, 2016 at 01:52:02AM +0300, Slawa Olhovchenkov wrote: > On Thu, Aug 11, 2016 at 10:36:37PM +0000, Glen Barber wrote: >=20 > > On Fri, Aug 12, 2016 at 01:33:31AM +0300, Slawa Olhovchenkov wrote: > > > On Thu, Aug 11, 2016 at 08:48:04PM +0000, Andriy Gapon wrote: > > >=20 > > > > Author: avg > > > > Date: Thu Aug 11 20:48:03 2016 > > > > New Revision: 303970 > > > > URL: https://svnweb.freebsd.org/changeset/base/303970 > > > >=20 > > > > Log: > > > > MFC r303763,303791,303869: zfs: honour and make use of vfs vnode = locking protocol > > > > =20 > > > > ZFS POSIX Layer is originally written for Solaris VFS which is ve= ry > > > > different from FreeBSD VFS. Most importantly many things that Fr= eeBSD VFS > > > > manages on behalf of all filesystems are implemented in ZPL in a = different > > > > way. > > > > Thus, ZPL contains code that is redundant on FreeBSD or duplicate= s VFS > > > > functionality or, in the worst cases, badly interacts / interferes > > > > with VFS. > > > > =20 > > > > The most prominent problem is a deadlock caused by the lock order= reversal > > > > of vnode locks that may happen with concurrent zfs_rename() and l= ookup(). > > > > The deadlock is a result of zfs_rename() not observing the vnode = locking > > > > contract expected by VFS. > > > > =20 > > > > This commit removes all ZPL internal locking that protects parent= -child > > > > relationships of filesystem nodes. These relationships are prote= cted > > > > by vnode locks and the code is changed to take advantage of that = fact > > > > and to properly interact with VFS. > > > > =20 > > > > Removal of the internal locking allowed all ZPL dmu_tx_assign cal= ls to > > > > use TXG_WAIT mode. > > > > =20 > > > > Another victim, disputable perhaps, is ZFS support for filesystem= s with > > > > mixed case sensitivity. That support is not provided by the OS a= nyway, > > > > so in ZFS it was a buch of dead code. > > > > =20 > > > > To do: > > > > - replace ZFS_ENTER mechanism with VFS managed / visible mechanism > > > > - replace zfs_zget with zfs_vget[f] as much as possible > > > > - get rid of not really useful now zfs_freebsd_* adapters > > > > - more cleanups of unneeded / unused code > > > > - fix / replace .zfs support > > >=20 > > > MFC to 10.x/9.x planed? > > >=20 > >=20 > > As I understand it, this does not affect stable/10. >=20 > Sure? > I think ZFS/VFS layers don't change between 9.x and 11.x >=20 No, but as I understand it, a commit to head tickled this bug. avg@ can correct me if I am wrong. Glen --8bBEDOJVaa9YlTAt Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJXrQLTAAoJEAMUWKVHj+KTIsUQAKMYQiFqVb3uT69rqtMBrs1F 4gbuUKWI/fovVirZ/tKjftQITj4WChZtabC7sW34wtS6Q5ja83B+4LUX++gf7Szi ivBD/Vo+FdBWpwxubJdxkK5jHoqreroyfXPGp5kITrGn5SiPaa5bARh9RaGFzA2g 7v/RAYobYHsYZcm11BsSHCg5H8aB5bqCgHXdX+YZ7ZvoE3H4hGzHfXzNVJsRKlaW DrcM0NMAVdfciAfe5cCRue3V6ODHXusjh3RWOaYmGAT+15fqz14JQAdyPwRpPdh0 pE1I7QLHqWL/64rc1cxLArag76f2RoeC+yQkk6w01S/tK81BZfZ/mxGQiK8ULe3R jkDUHGdTXUx00qKA/uRCVMZRda5VBBZs5GbqvtRiYOiWYrzkcVZkfwfFq77SQjTi ZmQwsPTK4HHG1FlGghnsAzrIrxbf7kEvFdoKiTOh+fS7IQiKPShSSbY/G1m+qQCv mwzVHhs18Cv3a+a3iulWO8iLH6ORrO2ETW8c63S2Q6IM+ausi9SLEBhwoBQm+hn0 1lu7zd4MggsqoaqCR5tYSqAJ+mWrjinr4c+y4RbzPSryXI4XFBTzuRL65hk+YsCL JEsu6U14wY6xCF10PjXK5g5kqZ4Q0YKOyjSLPEvMplsLWZMPFCZFSL/4cKc1AqkI UTrETCW2bWlHQ2t/tH3a =hlOr -----END PGP SIGNATURE----- --8bBEDOJVaa9YlTAt--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20160811225723.GG51184>