Hi, Arnd, On Tue, Jul 6, 2021 at 6:17 PM Arnd Bergmann <arnd@xxxxxxxx> wrote: > > On Tue, Jul 6, 2021 at 6:18 AM Huacai Chen <chenhuacai@xxxxxxxxxxx> wrote: > > > > +/* > > + * long __strncpy_from_user(char *to, const char *from, long len) > > + * > > + * a0: to > > + * a1: from > > + * a2: len > > + */ > > +SYM_FUNC_START(__strncpy_from_user) > > + move a3, zero > > + > > I doubt this is better than the C version in lib/strncpy_from_user.c OK, they will be replaced with the C version. Huacai > > > diff --git a/arch/loongarch/lib/strnlen_user.S b/arch/loongarch/lib/strnlen_user.S > > new file mode 100644 > > index 000000000000..9288a5ad294e > > --- /dev/null > > +++ b/arch/loongarch/lib/strnlen_user.S > > @@ -0,0 +1,47 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +/* > > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited > > + */ > > Same here. > > Have you done any measurement to show that the asm version actually helps > here? If not, just use the generic version. > > > Arnd
