mirror_zfs/module/spl
Brian Behlendorf 3982d959c5 Linux 5.3 compat: retire rw_tryupgrade()
The Linux kernel's rwsem's have never provided an interface to
allow a reader to be upgraded to a writer.  Historically, this
functionality has been implemented by a SPL wrapper function.
However, this approach depends on internal knowledge of the
rw_semaphore and is therefore rather brittle.

Since the ZFS code must always be able to fallback to rw_exit()
and rw_enter() when an rw_tryupgrade() fails; this functionality
isn't critical.  Furthermore, the only potentially performance
sensitive consumer is dmu_zfetch() and no decrease in performance
was observed with this change applied.  See the PR comments for
additional testing details.

Therefore, it is being retired to make the build more robust and
to simplify the rwlock implementation.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9029
2019-09-25 11:27:49 -07:00
..
Makefile.in Fixes for procfs files backed by linked lists 2018-09-26 11:08:12 -07:00
README.md Update build system and packaging 2018-05-29 16:00:33 -07:00
spl-atomic.c Fix cstyle warnings 2018-02-07 11:49:38 -08:00
spl-condvar.c kernel timer API rework 2019-09-25 11:27:46 -07:00
spl-cred.c Fix cstyle warnings 2018-02-07 11:49:38 -08:00
spl-err.c Correct snprintf() size argument 2019-04-30 19:41:12 -07:00
spl-generic.c Add missing trailing '\n' in printk() messages 2019-05-08 16:43:55 -07:00
spl-kmem-cache.c Fix style of spl_kmem_cache_create() 2019-02-28 17:57:47 -08:00
spl-kmem.c Add missing __GFP_HIGHMEM flag to vmalloc 2019-09-25 11:27:49 -07:00
spl-kobj.c Fix cstyle warnings 2018-02-07 11:49:38 -08:00
spl-kstat.c Unbreak build on Linux kernel < 3.10 2019-04-08 14:59:24 -07:00
spl-mutex.c Fix cstyle warnings 2018-02-07 11:49:38 -08:00
spl-proc.c Create /proc/sys/kernel/spl/gitrev with git hash 2018-10-08 21:57:02 -07:00
spl-procfs-list.c Restrict kstats and print real pointers 2019-04-04 18:57:06 -07:00
spl-rwlock.c Linux 5.3 compat: retire rw_tryupgrade() 2019-09-25 11:27:49 -07:00
spl-taskq.c kernel timer API rework 2019-09-25 11:27:46 -07:00
spl-thread.c Minor style cleanup 2019-09-25 11:27:49 -07:00
spl-tsd.c Remove all spin_is_locked calls 2017-10-30 11:16:56 -07:00
spl-vmem.c Prepare SPL repo to merge with ZFS repo 2018-05-29 14:51:39 -07:00
spl-vnode.c Remove vn_set_fs_pwd()/vn_set_pwd() (no need to be at / during insmod) 2019-09-25 11:27:46 -07:00
spl-xdr.c Update build system and packaging 2018-05-29 16:00:33 -07:00
spl-zlib.c Prepare SPL repo to merge with ZFS repo 2018-05-29 14:51:39 -07:00
THIRDPARTYLICENSE.gplv2 Prepare SPL repo to merge with ZFS repo 2018-05-29 14:51:39 -07:00
THIRDPARTYLICENSE.gplv2.descrip Prepare SPL repo to merge with ZFS repo 2018-05-29 14:51:39 -07:00

The Solaris Porting Layer, SPL, is a Linux kernel module which provides a compatibility layer used by the ZFS on Linux project.

Installation

The latest version of the SPL is maintained as part of this repository. Only when building ZFS version 0.7.x or earlier must an external SPL release be used. These releases can be found at:

Release

The SPL is released under a GPLv2 license.
For more details see the NOTICE and THIRDPARTYLICENSE files; UCRL-CODE-235197