1 files changed, 27 insertions, 0 deletions

diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index 2a609dc3271c..f47b9b5440d2 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -1109,6 +1109,33 @@ ENDPROC(xen_failsafe_callback)
 
 #endif  /* CONFIG_XEN */
 
+#ifdef CONFIG_FTRACE
+ENTRY(mcount)
+        cmpl $ftrace_stub, ftrace_trace_function
+        jnz trace
+
+.globl ftrace_stub
+ftrace_stub:
+        ret
+
+        /* taken from glibc */
+trace:
+        pushl %eax
+        pushl %ecx
+        pushl %edx
+        movl 0xc(%esp), %eax
+        movl 0x4(%ebp), %edx
+
+        call   *ftrace_trace_function
+
+        popl %edx
+        popl %ecx
+        popl %eax
+
+        jmp ftrace_stub
+END(mcount)
+#endif
+
 .section .rodata,"a"
 #include "syscall_table_32.S"