On Fri, Feb 19, 2016 at 10:30:09AM +0800, Zhi-zhou wrote: > On Thu, Feb 18, 2016 at 7:58 PM, Catalin Marinas > <[email protected]> wrote: > > > > On Thu, Feb 18, 2016 at 07:48:35PM +0800, Zhi-zhou Zhang wrote: > > > From: zhizhou <[email protected]> > > > > > > This patch is based on the implementation of arm. The generic > > > current_pt_regs is implemented with current->stack. It need to access > > > memory that would be too expensive. > > > > Do you have any performance numbers? > > I'm using QEMU, so no. Actually this macro isn't heavily used. I just > think using the generic > implementation is not very nice. It get task_struct from sp_el0, then > get stack(which is > equal to sp_el0) from task_struct. There are two unnecessary memory accesses.
I'd much rather use the generic implementation unless there's a compelling reason not to. "I think it's not very nice" doesn't really cut it for me! Will
