http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50065
--- Comment #9 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2011-08-15
08:47:08 UTC ---
> Regarding the spinlock_unlock in linux, the regular arch_spin_unlock is
> implemented with a single inline assembly. That will prevent the memory
> reordering in C. However, for the 32-bit port the arch_write_unlock is still
> defined as the following without a memory barrier in
> arch/sparc/include/asm/spinlock_32.h
>
> #define arch_write_unlock(rw) do { (rw)->lock = 0; } while(0)
>
> OTH, the 64-bit implemention is ok. Or did I miss something here.
> Anyway, I think this is a separated issue from this thread.
The discrepancy is a little surprising, indeed.
