On Mon, 21 Oct 2024 17:46:19 +0100 Will Deacon <[email protected]> wrote:
> 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? Good catch! I will update it. Thank you! > > Will -- Masami Hiramatsu (Google) <[email protected]>
