________________________________________ >From: Vineet Gupta <Vineet.Gupta1 at synopsys.com> >Sent: Thursday, February 4, 2016 6:13 AM >Noam, what's the atomic story for EZChip. Do you support such things for user space in GNU tools. If -atomic is added to perf user space builds are you guys OK! Well here for EZchip I also see the: undefined reference to `__sync_add_and_fetch_4' undefined reference to `__sync_sub_and_fetch_4' 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. -Noam
