On Fri, Jan 26, 2018 at 6:24 AM, Alan Cox <[email protected]> wrote: >> NetBSD (and the other BSD?) defines a structure for the arguments to >> each syscall. > > Goes back to v7 or so but they put the syscall arguments into the uarea > so that no pointers were needed (uarea being a per process mapping at a > fixed address) in order to also reduce pointer dereferencing costs (not > that those matter much on modern processors) >
I gave the rearrangement like this a try yesterday and it's a bit of a mess. Part of the problem is that there are a bunch of pieces of code that expect sys_xyz() to be actual callable functions. The best way to deal with that is probably to switch to calling normal functions.
