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SubjectRe: [PATCH] x86/ftrace: usr ftrace_write to simplify code
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I am sorry.

usr => use in subject.

I will resend this patch.

 --Cheng Jian

On 2020/1/13 15:33, Cheng Jian wrote:
> ftrace_write() can be used directly in ftrace_modify_code_direct(),
> that make the code more brief.
>
> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com>
> ---
> arch/x86/kernel/ftrace.c | 24 +++++++++++-------------
> 1 file changed, 11 insertions(+), 13 deletions(-)
>
> diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
> index 024c3053dbba..6b36ed2fd04d 100644
> --- a/arch/x86/kernel/ftrace.c
> +++ b/arch/x86/kernel/ftrace.c
> @@ -114,6 +114,16 @@ static const unsigned char *ftrace_nop_replace(void)
> return ideal_nops[NOP_ATOMIC5];
> }
>
> +static int ftrace_write(unsigned long ip, const char *val, int size)
> +{
> + ip = text_ip_addr(ip);
> +
> + if (probe_kernel_write((void *)ip, val, size))
> + return -EPERM;
> +
> + return 0;
> +}
> +
> static int
> ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code,
> unsigned const char *new_code)
> @@ -138,10 +148,8 @@ ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code,
> if (memcmp(replaced, old_code, MCOUNT_INSN_SIZE) != 0)
> return -EINVAL;
>
> - ip = text_ip_addr(ip);
> -
> /* replace the text with the new text */
> - if (probe_kernel_write((void *)ip, new_code, MCOUNT_INSN_SIZE))
> + if (ftrace_write(ip, new_code, MCOUNT_INSN_SIZE))
> return -EPERM;
>
> sync_core();
> @@ -326,16 +334,6 @@ int ftrace_int3_handler(struct pt_regs *regs)
> }
> NOKPROBE_SYMBOL(ftrace_int3_handler);
>
> -static int ftrace_write(unsigned long ip, const char *val, int size)
> -{
> - ip = text_ip_addr(ip);
> -
> - if (probe_kernel_write((void *)ip, val, size))
> - return -EPERM;
> -
> - return 0;
> -}
> -
> static int add_break(unsigned long ip, const char *old)
> {
> unsigned char replaced[MCOUNT_INSN_SIZE];

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