4 files changed, 71 insertions, 0 deletions

diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 3d31636cbafb..b992ba447c41 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -21,6 +21,7 @@ config IA64
         select HAVE_OPROFILE
         select HAVE_KPROBES
         select HAVE_KRETPROBES
+        select HAVE_FUNCTION_TRACER
         select HAVE_DMA_ATTRS
         select HAVE_KVM
         select HAVE_ARCH_TRACEHOOK
diff --git a/arch/ia64/include/asm/ftrace.h b/arch/ia64/include/asm/ftrace.h
new file mode 100644
index 000000000000..48694b3ba5a8
--- /dev/null
+++ b/arch/ia64/include/asm/ftrace.h
@@ -0,0 +1,15 @@
+#ifndef _ASM_IA64_FTRACE_H
+#define _ASM_IA64_FTRACE_H
+
+#ifdef CONFIG_FUNCTION_TRACER
+#define MCOUNT_INSN_SIZE        32 /* sizeof mcount call */
+
+#ifndef __ASSEMBLY__
+extern void _mcount(unsigned long pfs, unsigned long r1, unsigned long b0, unsigned long r0);
+#define mcount _mcount
+
+#endif
+
+#endif /* CONFIG_FUNCTION_TRACER */
+
+#endif /* _ASM_IA64_FTRACE_H */
diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index d435f4a7a96c..c2f7d798e2a5 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -47,6 +47,7 @@
 #include <asm/processor.h>
 #include <asm/thread_info.h>
 #include <asm/unistd.h>
+#include <asm/ftrace.h>
 
 #include "minstate.h"
 
@@ -1404,6 +1405,54 @@ GLOBAL_ENTRY(unw_init_running)
         br.ret.sptk.many rp
 END(unw_init_running)
 
+#ifdef CONFIG_FUNCTION_TRACER
+GLOBAL_ENTRY(_mcount)
+        movl r2 = ftrace_stub
+        movl r3 = ftrace_trace_function;;
+        ld8 r3 = [r3];;
+        ld8 r3 = [r3];;
+        cmp.eq p7,p0 = r2, r3
+(p7)    br.sptk.many ftrace_stub
+        ;;
+
+        alloc loc0 = ar.pfs, 4, 4, 2, 0
+        ;;
+        mov loc1 = b0
+        mov out0 = b0
+        mov loc2 = r8
+        mov loc3 = r15
+        ;;
+        adds out0 = -MCOUNT_INSN_SIZE, out0
+        mov out1 = in2
+        mov b6 = r3
+
+        br.call.sptk.many b0 = b6
+        ;;
+        mov ar.pfs = loc0
+        mov b0 = loc1
+        mov r8 = loc2
+        mov r15 = loc3
+        br ftrace_stub
+        ;;
+END(_mcount)
+
+GLOBAL_ENTRY(ftrace_stub)
+        mov r3 = b0
+        movl r2 = _mcount_ret_helper
+        ;;
+        mov b6 = r2
+        mov b7 = r3
+        br.ret.sptk.many b6
+
+_mcount_ret_helper:
+        mov b0 = r42
+        mov r1 = r41
+        mov ar.pfs = r40
+        br b7
+END(ftrace_stub)
+
+#endif /* CONFIG_FUNCTION_TRACER */
+
         .rodata
         .align 8
         .globl sys_call_table
diff --git a/arch/ia64/kernel/ia64_ksyms.c b/arch/ia64/kernel/ia64_ksyms.c
index 6da1f20d7372..2d311864e359 100644
--- a/arch/ia64/kernel/ia64_ksyms.c
+++ b/arch/ia64/kernel/ia64_ksyms.c
@@ -112,3 +112,9 @@ EXPORT_SYMBOL_GPL(esi_call_phys);
 #endif
 extern char ia64_ivt[];
 EXPORT_SYMBOL(ia64_ivt);
+
+#include <asm/ftrace.h>
+#ifdef CONFIG_FUNCTION_TRACER
+/* mcount is defined in assembly */
+EXPORT_SYMBOL(_mcount);
+#endif