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Subject[PATCH] x86/ftrace: use ftrace_write to simplify code
Date
ftrace_write() can be used 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];
--
2.17.1
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