> Hi all > > I have been playing with the copy_page() function in arch/ppc/kernel/misc.S > and gained about 30% speed up for my mpc860, rev D4 MHz. > > This is what i did: > - Use dcbz on 8xx but clear ahead one cache line(performance is really crappy > if I don't clear ahead). This is the biggest improvement. > - Use prefetch for 8xx as well. > > I know that dcbz is buggy for some 8xx CPUs but I don't know which ones. > For me works just fine, except in copy_tofrom_user(don't know why).
hmm, I made two versions of copy_tofrom_user(), copy_from_user() and copy_to_user() and modified asm/uaccess.h to reflect this. Then I modified copy_from_user() to use dcbz on the destination area. Booted and started our app and it works just fine! Jocke ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
