operation as a write barrier. That description has never been correct,
and it has caused confusion. An acquire operation orders writes as well
as reads, and a release operation orders reads as well as writes.
Also, explicitly say that a thread doesn't see its own accesses being
reordered. The reordering of a thread's accesses is only (potentially)
visible to another thread. Thus, memory barriers need only be used to
control the ordering of accesses between threads, not within a thread.
Reviewed by: bde, kib
Discussed with: jhb
MFC after: 1 week
multiple processors. In particular, clearly state that the operations
are always atomic when they are applied to the default memory type
that is used by the kernel (and applications).
Reviewed by: kib, jhb (an earlier version)
MFC after: 1 week
release barriers, not read and write barriers. They fence all memory
accesses from the respective side, not limited by the kind of
operation.
Reviewed by: jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
This includes:
o All directories named *ia64*
o All files named *ia64*
o All ia64-specific code guarded by __ia64__
o All ia64-specific makefile logic
o Mention of ia64 in comments and documentation
This excludes:
o Everything under contrib/
o Everything under crypto/
o sys/xen/interface
o sys/sys/elf_common.h
Discussed at: BSDcan
Although groff_mdoc(7) gives another impression, this is the ordering
most widely used and also required by mdocml/mandoc.
Reviewed by: ru
Approved by: philip, ed (mentors)
- Add arm and ppc to the list of archs not supporting operations on 64-bit
integers.
- Update the sample code for acquiring a mutex to be more recent and to
take into account the recent atomic_foo_ptr() changes.
MFC after: 1 week
Nuke incorrect usage of .Ar; replace it with .Vt, .Va or .Fa appropriately.
The .Ar mdoc(7) specifier should only be used when displaying command line
arguments.
Approved by: des (mentor)
