Commit 92550405 authored by Steven Rostedt (Red Hat)'s avatar Steven Rostedt (Red Hat) Committed by Steven Rostedt
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ftrace/x86: Have ftrace_write() return -EPERM and clean up callers 



Having ftrace_write() return -EPERM on failure, as that's what the callers
return, then we can clean up the code a bit. That is, instead of:

  if (ftrace_write(...))
     return -EPERM;
  return 0;

or

  if (ftrace_write(...)) {
     ret = -EPERM;
     goto_out;
  }

We can instead have:

  return ftrace_write(...);

or

  ret = ftrace_write(...);
  if (ret)
    goto out;

Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 7dec935a

arch/x86/kernel/ftrace.c

+8 −19
Original line number Diff line number Diff line
@@ -308,7 +308,10 @@ static int ftrace_write(unsigned long ip, const char *val, int size) 
	if (within(ip, (unsigned long)_text, (unsigned long)_etext))

		ip = (unsigned long)__va(__pa_symbol(ip));



	return probe_kernel_write((void *)ip, val, size);

	if (probe_kernel_write((void *)ip, val, size))

		return -EPERM;



	return 0;

}



static int add_break(unsigned long ip, const char *old)
@@ -323,10 +326,7 @@ static int add_break(unsigned long ip, const char *old) 
	if (memcmp(replaced, old, MCOUNT_INSN_SIZE) != 0)

		return -EINVAL;



	if (ftrace_write(ip, &brk, 1))

		return -EPERM;



	return 0;

	return ftrace_write(ip, &brk, 1);

}



static int add_brk_on_call(struct dyn_ftrace *rec, unsigned long addr)
@@ -463,9 +463,7 @@ static int add_update_code(unsigned long ip, unsigned const char *new) 
	/* skip breakpoint */

	ip++;

	new++;

	if (ftrace_write(ip, new, MCOUNT_INSN_SIZE - 1))

		return -EPERM;

	return 0;

	return ftrace_write(ip, new, MCOUNT_INSN_SIZE - 1);

}



static int add_update_call(struct dyn_ftrace *rec, unsigned long addr)
@@ -520,10 +518,7 @@ static int finish_update_call(struct dyn_ftrace *rec, unsigned long addr) 


	new = ftrace_call_replace(ip, addr);



	if (ftrace_write(ip, new, 1))

		return -EPERM;



	return 0;

	return ftrace_write(ip, new, 1);

}



static int finish_update_nop(struct dyn_ftrace *rec)
@@ -533,9 +528,7 @@ static int finish_update_nop(struct dyn_ftrace *rec) 


	new = ftrace_nop_replace();



	if (ftrace_write(ip, new, 1))

		return -EPERM;

	return 0;

	return ftrace_write(ip, new, 1);

}



static int finish_update(struct dyn_ftrace *rec, int enable)
@@ -656,10 +649,6 @@ ftrace_modify_code(unsigned long ip, unsigned const char *old_code, 
	run_sync();



	ret = ftrace_write(ip, new_code, 1);

	if (ret) {

		ret = -EPERM;

		goto out;

	}

 out:

	run_sync();

	return ret;

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