> To improve responsiveness, disable preemption for each step of the > walk (which is at most PAGE_SIZE) rather than for the entire > encryption/decryption operation. It seems that it is not that uncommon for IPsec to get small inputs scattered over multiple blocks. Doing FPU context saving for each walk step then can slow down things. An alternative approach could be to re-enable preemption not based on the walk steps, but on the amount of bytes processed. This would satisfy both users, I guess. In the long run we probably need a better approach for FPU context saving, as this really hurts performance-wise. For IPsec we should find a way to avoid the (multiple) per-packet FPU save/restores in softirq context, but I guess this requires support from process context switching. Best regards Martin
