Christophe Leroy's on August 28, 2019 7:06 pm:

Le 27/08/2019 à 15:55, Nicholas Piggin a écrit :

quoted

Accounted for some feedback.

Nicholas Piggin (4):
   powerpc: convert to copy_thread_tls
   powerpc/64: remove support for kernel-mode syscalls
   powerpc/64: system call remove non-volatile GPR save optimisation
   powerpc/64: system call implement the bulk of the logic in C

Would it be possible to split in the following parts:

1/ Implement in C whatever can be implemented without removing 
non-volatile GPR save optimisation
2/ Remove non-volatile GPR save optimisation
3/ Implement in C everything else

Hmm. I'll have a look but I would rather not go back and add the
intermediate state I was hoping to avoid. I'll think about it and
if it's not too difficult I will try to add something. I have an
idea.

With your nvregs performance test on ppc32, are you doing the
nvgpr restore? The fast path should be able to avoid that.

Thanks,
Nick