Nicholas Piggin's on August 28, 2019 7:06 pm: > This is a work in progress that goes on top of the syscalls in C patch. > It's not quite complete, 64e low level exit is not taken care of, and > the new return is hacked into the existing interrupt handlers pretty > quickly (e.g., full gprs handling is still ugly and could be cleaned),
In performance testing on a POWER9, page fault latency is about 1.1% faster with interrupt returns in C which always saves NVGPRs. So I think the plan will be to rip out all the NVGPR save optimisation from the 64-bit code. Thanks, Nick
