On Wed, May 18, 2022 at 3:53 PM Xu Kuohai <xukuohai@xxxxxxxxxx> wrote: > > Add ftrace direct support for arm64. > > 1. When there is custom trampoline only, replace the fentry nop to a > jump instruction that jumps directly to the custom trampoline. > > 2. When ftrace trampoline and custom trampoline coexist, jump from > fentry to ftrace trampoline first, then jump to custom trampoline > when ftrace trampoline exits. The current unused register > pt_regs->orig_x0 is used as an intermediary for jumping from ftrace > trampoline to custom trampoline. > > Signed-off-by: Xu Kuohai <xukuohai@xxxxxxxxxx> > Acked-by: Song Liu <songliubraving@xxxxxx> Acked-by: KP Singh <kpsingh@xxxxxxxxxx>
