mirror_zfs/module
Brian Behlendorf bff2361aeb
Linux 5.2 compat: rw_tryupgrade()
Commit torvalds/linux@46ad0840b has removed the architecture specific
rwsem source and headers leaving only the generic version.  As part
of this change the RWSEM_ACTIVE_READ_BIAS and RWSEM_ACTIVE_WRITE_BIAS
macros were moved to the private kernel/locking/rwsem.h header.
This results in a build failure because these macros were required
to implement the rw_tryupgrade() compatibility function.

In practice, this isn't a major problem because there are only a
few consumers of rw_tryupgrade() and because consumers of rw_tryupgrade
should be written to retry using rw_enter(RW_WRITER).

After auditing all of the callers only dmu_zfetch() was determined
not to perform a retry.  It has been updated in this commit to
resolve this issue.

That said, the rw_tryupgrade() functionality should be considered
for possible removal in a future release due to the difficultly
in supporting the interface.

Reviewed-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8730
2019-05-23 13:46:33 -07:00
..
avl Update build system and packaging 2018-05-29 16:00:33 -07:00
icp Restructure vec_idx loops 2019-04-16 12:34:06 -07:00
lua Update build system and packaging 2018-05-29 16:00:33 -07:00
nvpair Use NV_ENCODE_NATIVE for nvlist encoding variable 2019-04-26 11:24:31 -07:00
spl Linux 5.2 compat: rw_tryupgrade() 2019-05-23 13:46:33 -07:00
unicode Update build system and packaging 2018-05-29 16:00:33 -07:00
zcommon Add TRIM support 2019-03-29 09:13:20 -07:00
zfs Linux 5.2 compat: rw_tryupgrade() 2019-05-23 13:46:33 -07:00
.gitignore Prepare SPL repo to merge with ZFS repo 2018-05-29 14:51:39 -07:00
Makefile.in Linux 5.0 compat: Fix SUBDIRs 2019-01-28 10:11:45 -08:00