diff options
| author | Oleg Nesterov | 2008-02-24 00:03:29 +0300 |
|---|---|---|
| committer | Linus Torvalds | 2008-02-23 17:52:36 -0800 |
| commit | 02c608c1fefe821a4c6fc34c45a0dea3cebf4764 (patch) | |
| tree | 8fd360da8bc83dd45ecec5621791baa73ddfac70 /Documentation/robust-futex-ABI.txt | |
| parent | 2dda81ca31dc73e695ff8b83351f7aaefbef192a (diff) | |
documentation: atomic_add_unless() doesn't imply mb() on failure
(sorry for being offtpoic, but while experts are here...)
A "typical" implementation of atomic_add_unless() can return 0 immediately
after the first atomic_read() (before doing cmpxchg). In that case it doesn't
provide any barrier semantics. See include/asm-ia64/atomic.h as an example.
We should either change the implementation, or fix the docs.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/robust-futex-ABI.txt')
0 files changed, 0 insertions, 0 deletions