Andrew Haley wrote:
Phil Endecott writes:
> Andrew Haley wrote:
> > this stuff really should be done by the compiler.
>
> Yes. I've filed a bug asking for a __sync_lock_test_and_set builtin:
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33413
Surer, but the problem is that for most of the things we want to do
(lightweight locks, for example) __sync_lock_test_and_set() doesn't
really do what we need: we need compare_and_swap(). That's why the
kernel helper is so useful, because it's robust even if we are on
pre-ARMv6 hardware.
Probably the enhancement request should be expanded to include *all* the
__sync_* atomic memory primitives which includes compare_and_swap.
David Daney
