ftrace, ia64: IA64 static ftrace support

IA64 ftrace suppport. In IA64, below code will be added in each function
if -pg is enabled.

alloc r40=ar.pfs,12,8,0
mov r43=r0;;
mov r42=b0
mov r41=r1
nop.i 0x0
br.call.sptk.many b0 = _mcount;;

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 3d31636cbafb584d25995e6ae6ff9d253a95901d..b992ba447c41d2d3e8321af08daad72e42bb18b4 100644 (file)
--- 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 (file)
index 0000000..48694b3
--- /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 d435f4a7a96c0f83203a3e4be44b099694b26311..c2f7d798e2a5bccce3a4f464ff61759c03945966 100644 (file)
--- 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 6da1f20d737239e2fced3c48c1cd89e6442621ee..2d311864e359d93036ae8e4b31d0e39f5ee56c4d 100644 (file)
--- 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