ftrace/x86_32: Simplify parameter setup for ftrace_regs_caller

The final position of the stack after saving regs and setting up
the parameters for ftrace_regs_call, is the position of the pt_regs
needed for the 4th parameter. Instead of saving it into a temporary
reg and pushing the reg, simply push the stack pointer.

Link: http://lkml.kernel.org/r/1342702344.12353.16.camel@gandalf.stny.rr.com
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index 46caa56..4dc3017 100644 (file)
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -1169,10 +1169,9 @@ ENTRY(ftrace_regs_caller)
        movl $__KERNEL_CS,13*4(%esp)
 
        movl 12*4(%esp), %eax   /* Load ip (1st parameter) */
-       movl 0x4(%ebp), %edx    /* Load parent ip (2cd parameter) */
-       lea  (%esp), %ecx
-       pushl %ecx              /* Save pt_regs as 4th parameter */
+       movl 0x4(%ebp), %edx    /* Load parent ip (2nd parameter) */
        leal function_trace_op, %ecx /* Save ftrace_pos in 3rd parameter */
+       pushl %esp              /* Save pt_regs as 4th parameter */
 
 GLOBAL(ftrace_regs_call)
        call ftrace_stub