Re: [RFC PATCH 4/5] csky: ftrace: Drop duplicate implementation of arch_check_ftrace_location()

From: Guo Ren
Date: Wed Jun 09 2021 - 08:33:37 EST


csky using -mcount not -fpatchable-function-entry, so
/* Given address is not on the instruction boundary */
if ((unsigned long)p->addr != ftrace_addr)
return -EILSEQ;
all right?

On Wed, Jun 9, 2021 at 6:51 PM Punit Agrawal <punitagrawal@xxxxxxxxx> wrote:
>
> The csky specific arch_check_ftrace_location() shadows a weak
> implementation of the function in core code that offers the same
> functionality but with additional error checking.
>
> Drop the architecture specific function as a step towards further
> cleanup in core code.
>
> Signed-off-by: Punit Agrawal <punitagrawal@xxxxxxxxx>
> Cc: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
> ---
> arch/csky/kernel/probes/ftrace.c | 7 -------
> 1 file changed, 7 deletions(-)
>
> diff --git a/arch/csky/kernel/probes/ftrace.c b/arch/csky/kernel/probes/ftrace.c
> index ef2bb9bd9605..b388228abbf2 100644
> --- a/arch/csky/kernel/probes/ftrace.c
> +++ b/arch/csky/kernel/probes/ftrace.c
> @@ -2,13 +2,6 @@
>
> #include <linux/kprobes.h>
>
> -int arch_check_ftrace_location(struct kprobe *p)
> -{
> - if (ftrace_location((unsigned long)p->addr))
> - p->flags |= KPROBE_FLAG_FTRACE;
> - return 0;
> -}
> -
> /* Ftrace callback handler for kprobes -- called under preepmt disabled */
> void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
> struct ftrace_ops *ops, struct ftrace_regs *fregs)
> --
> 2.30.2
>


--
Best Regards
Guo Ren

ML: https://lore.kernel.org/linux-csky/