On Tue, 11 Dec 2018 04:59:26 PST (-0800), yamada.masahiro@xxxxxxxxxxxxx wrote: > Hi Christoph, > > > On Fri, Dec 7, 2018 at 12:04 AM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: >> >> On Wed, Dec 05, 2018 at 08:28:05PM +0900, Masahiro Yamada wrote: >> > Some time ago, Sam pointed out a certain degree of overwrap between >> > generic-y and mandatory-y. (https://lkml.org/lkml/2017/7/10/121) >> > >> > I a bit tweaked the meaning of mandatory-y; now it defines the minimum >> > set of ASM headers that all architectures must have. >> > >> > If arch does not have specific implementation of a mandatory header, >> > Kbuild will let it fallback to the asm-generic one by automatically >> > generating a wrapper. This will allow to drop lots of redundant >> > generic-y defines. >> > >> > Previously, "mandatory" was used in the context of UAPI, but I guess >> > this can be extended to kernel space ASM headers. >> >> How useful is it to keep the generic-y behavior around at all vs making >> everything useful mandatory? > > > What I can tell is not all architectures > support kvm_para.h, ucontext.h > > I guess they will stay as arch-specific generic-y, > but I am not an expert in this area. > > > kvm_para.h is missing csky, nds32, riscv. It looks like RISC-V missed it and everyone else copied us. I don't see any reason why the generic version wouldn't work on RISC-V, as it just has failures for all the calls. > ucontext.h is missing in alpha, arm, m68k, parisc, sparc, xtensa > > > > bpf_perf_event.h could be promoted to mandatory-y ? > All architectures have it.
