On Wed, Jul 04, 2018 at 06:41:34PM +0100, Will Deacon wrote: > On Wed, Jul 04, 2018 at 05:37:23PM +0100, Mark Rutland wrote: > > On Wed, Jul 04, 2018 at 04:24:22PM +0100, Will Deacon wrote: > > > This is mostly straightforward, but the cmpxchg/cmpxchg_double cases grow > > > an 'arch' prefix which suggests that they're part of the API with the core > > > atomics and also makes them horribly ugly. > > > > I agree this isn't nice. > > > > > This just looks to be an artifact of __LL_SC_CALL pasting that in. Can > > > you drop that auto pasting of 'arch', and instead change the > > > non-cmpxchg-case callers of the macro to include the arch prefix > > > instead, please? > > > > That leads to having an arch___llsc_ prefix in some cases, which is > > equally hideous. > > Yuck, how does that come about? > > > How about I remove the prefix mangling entirely, and always give > > functions an __llsc_ or __lse_ prefix. Then, unify the two in our > > atomic.h with: > > > > #ifdef CONFIG_ARM64_LSE > > #define ATOMIC_PFX __lse_ > > #else > > #define ATOMIC_PFX __ll_sc_ > > #endif > > > > #define arch_atomic_foo ATOMIC_PFX##atomic_foo > > #define arch_atomic_bar ATOMIC_PFX##atomic_bar > > > > ... which clearly delineates the implementation from core API. > > > > Does that sound ok to you? > > Why do we need two prefixes? The only reason we throw out __ll_sc_ at the > moment is so the out-of-line atomics have a different name from the inlined > ones. What I'd like is: > > atomic_foo > -> arch_atomic_foo > -> optionally calls __ll_sc_arch_atomic_foo > > which I think is very similar to what we already do (i.e. the inlined macro > is always called arch_atomic_foo, regardless of lse or ll/sc).
Sure; so long as you're happy with __ll_sc_arch_atomic_foo, that works. I'll rework things to that effect for v3. Thanks, Mark.
