> > 2) These mutexes are based on futexes which requires atomic > > operations in userspace. These are available on most architectures. Look at > > the glibc code in > > nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h for instance. > > Use that and your PPC manual to implement your atomic operations. > > No matter semaphore or futex, it uses system calls to kernel. And the > true atomic operation is in kernel not user space. Maybe > it's feasible > for other architectures to do atomic operations directly in > user space. > IMHO, not for powerpc.
Are you meaning that we didn't do atomic operations directly in user space on powerpc platform ? -DAve
