On Wed, Oct 16, 2024 at 09:59:00AM +0900, Masami Hiramatsu (Google) wrote: > From: Masami Hiramatsu (Google) <[email protected]> > > Add ftrace_partial_regs() which converts the ftrace_regs to pt_regs. > This is for the eBPF which needs this to keep the same pt_regs interface > to access registers. > Thus when replacing the pt_regs with ftrace_regs in fprobes (which is > used by kprobe_multi eBPF event), this will be used. > > If the architecture defines its own ftrace_regs, this copies partial > registers to pt_regs and returns it. If not, ftrace_regs is the same as > pt_regs and ftrace_partial_regs() will return ftrace_regs::regs. > > Signed-off-by: Masami Hiramatsu (Google) <[email protected]> > Acked-by: Florent Revest <[email protected]> > Cc: Steven Rostedt <[email protected]> > Cc: Mark Rutland <[email protected]> > Cc: Catalin Marinas <[email protected]> > Cc: Will Deacon <[email protected]> > Cc: Paul Walmsley <[email protected]> > Cc: Palmer Dabbelt <[email protected]> > Cc: Albert Ou <[email protected]> > > --- > Changes in v14: > - Add riscv change. > Changes in v8: > - Add the reason why this required in changelog. > Changes from previous series: NOTHING, just forward ported. > --- > arch/arm64/include/asm/ftrace.h | 11 +++++++++++ > arch/riscv/include/asm/ftrace.h | 14 ++++++++++++++ > include/linux/ftrace.h | 17 +++++++++++++++++ > 3 files changed, 42 insertions(+) > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > index b5fa57b61378..d344c69eb01e 100644 > --- a/arch/arm64/include/asm/ftrace.h > +++ b/arch/arm64/include/asm/ftrace.h > @@ -135,6 +135,17 @@ ftrace_regs_get_frame_pointer(const struct ftrace_regs > *fregs) > return arch_ftrace_regs(fregs)->fp; > } > > +static __always_inline struct pt_regs * > +ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) > +{ > + memcpy(regs->regs, arch_ftrace_regs(fregs)->regs, sizeof(u64) * 9);
Since ftrace_regs::regs is an 'unsigned long regs[9]' can we just use sizeof() on that instead of hard-coding the length of the array here? Will
