Em Fri, Feb 05, 2016 at 11:18:52AM +0000, Noam Camus escreveu: > Well here for EZchip I also see the: > undefined reference to `__sync_add_and_fetch_4' > undefined reference to `__sync_sub_and_fetch_4' Yeah, because there is no: tools/arch/arc/include/asm/atomic.h, can't you guys adapt arch/arc/include/asm/atomic.h to use in userspace? - Arnaldo > This is since at file tools/include/asm/atomic.h we use the generic implementation > If for ARC I could use just like x86 my own header file then functions like: > atomic_inc() > atomic_dec_and_test() > Are easy to implement and you may see an example for such atomic methods in my patch set for the new platform. > > You however wants to use some GCC flag -matomic which I assume somehow will implement the above __sync*. > I can't find the implementation but if it uses LLSC then it won't work for me since I am not supporting LLSC. > So seem that either I have my own header at kernel or that I need to > change the GCC implementation for __sync* to use my atomic > instructions. I am personally tend to the x86 solution and not the > generic one since changing GCC will require to have new compiler > dependency.
