x86: entry_64 - introduce FTRACE_ frame macro v2

Impact: clean up

Itroduce MCOUNT_SAVE/RESTORE_FRAME which allow us to
save a number of lines on source level.

Also fix a comment in ftrace.h.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 35 insertions, 51 deletions

diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h
index 7e61b4ceb9a4..b55b4a7fbefd 100644
--- a/arch/x86/include/asm/ftrace.h
+++ b/arch/x86/include/asm/ftrace.h
@@ -1,6 +1,33 @@
 #ifndef _ASM_X86_FTRACE_H
 #define _ASM_X86_FTRACE_H
 
+#ifdef __ASSEMBLY__
+
+        .macro MCOUNT_SAVE_FRAME
+        /* taken from glibc */
+        subq $0x38, %rsp
+        movq %rax, (%rsp)
+        movq %rcx, 8(%rsp)
+        movq %rdx, 16(%rsp)
+        movq %rsi, 24(%rsp)
+        movq %rdi, 32(%rsp)
+        movq %r8, 40(%rsp)
+        movq %r9, 48(%rsp)
+        .endm
+
+        .macro MCOUNT_RESTORE_FRAME
+        movq 48(%rsp), %r9
+        movq 40(%rsp), %r8
+        movq 32(%rsp), %rdi
+        movq 24(%rsp), %rsi
+        movq 16(%rsp), %rdx
+        movq 8(%rsp), %rcx
+        movq (%rsp), %rax
+        addq $0x38, %rsp
+        .endm
+
+#endif
+
 #ifdef CONFIG_FUNCTION_TRACER
 #define MCOUNT_ADDR             ((long)(mcount))
 #define MCOUNT_INSN_SIZE        5 /* sizeof mcount call */
@@ -46,7 +73,7 @@ struct ftrace_ret_stack {
 /*
  * Primary handler of a function return.
  * It relays on ftrace_return_to_handler.
- * Defined in entry32.S
+ * Defined in entry_32/64.S
  */
 extern void return_to_handler(void);
 
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 54e0bbdccb99..303dd84d2a98 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -71,15 +71,7 @@ ENTRY(ftrace_caller)
         cmpl $0, function_trace_stop
         jne  ftrace_stub
 
-        /* taken from glibc */
-        subq $0x38, %rsp
-        movq %rax, (%rsp)
-        movq %rcx, 8(%rsp)
-        movq %rdx, 16(%rsp)
-        movq %rsi, 24(%rsp)
-        movq %rdi, 32(%rsp)
-        movq %r8, 40(%rsp)
-        movq %r9, 48(%rsp)
+        MCOUNT_SAVE_FRAME
 
         movq 0x38(%rsp), %rdi
         movq 8(%rbp), %rsi
@@ -89,14 +81,7 @@ ENTRY(ftrace_caller)
 ftrace_call:
         call ftrace_stub
 
-        movq 48(%rsp), %r9
-        movq 40(%rsp), %r8
-        movq 32(%rsp), %rdi
-        movq 24(%rsp), %rsi
-        movq 16(%rsp), %rdx
-        movq 8(%rsp), %rcx
-        movq (%rsp), %rax
-        addq $0x38, %rsp
+        MCOUNT_RESTORE_FRAME
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 .globl ftrace_graph_call
@@ -130,15 +115,7 @@ ftrace_stub:
         retq
 
 trace:
-        /* taken from glibc */
-        subq $0x38, %rsp
-        movq %rax, (%rsp)
-        movq %rcx, 8(%rsp)
-        movq %rdx, 16(%rsp)
-        movq %rsi, 24(%rsp)
-        movq %rdi, 32(%rsp)
-        movq %r8, 40(%rsp)
-        movq %r9, 48(%rsp)
+        MCOUNT_SAVE_FRAME
 
         movq 0x38(%rsp), %rdi
         movq 8(%rbp), %rsi
@@ -146,14 +123,7 @@ trace:
 
         call   *ftrace_trace_function
 
-        movq 48(%rsp), %r9
-        movq 40(%rsp), %r8
-        movq 32(%rsp), %rdi
-        movq 24(%rsp), %rsi
-        movq 16(%rsp), %rdx
-        movq 8(%rsp), %rcx
-        movq (%rsp), %rax
-        addq $0x38, %rsp
+        MCOUNT_RESTORE_FRAME
 
         jmp ftrace_stub
 END(mcount)
@@ -165,14 +135,7 @@ ENTRY(ftrace_graph_caller)
         cmpl $0, function_trace_stop
         jne ftrace_stub
 
-        subq $0x38, %rsp
-        movq %rax, (%rsp)
-        movq %rcx, 8(%rsp)
-        movq %rdx, 16(%rsp)
-        movq %rsi, 24(%rsp)
-        movq %rdi, 32(%rsp)
-        movq %r8, 40(%rsp)
-        movq %r9, 48(%rsp)
+        MCOUNT_SAVE_FRAME
 
         leaq 8(%rbp), %rdi
         movq 0x38(%rsp), %rsi
@@ -180,14 +143,8 @@ ENTRY(ftrace_graph_caller)
 
         call    prepare_ftrace_return
 
-        movq 48(%rsp), %r9
-        movq 40(%rsp), %r8
-        movq 32(%rsp), %rdi
-        movq 24(%rsp), %rsi
-        movq 16(%rsp), %rdx
-        movq 8(%rsp), %rcx
-        movq (%rsp), %rax
-        addq $0x38, %rsp
+        MCOUNT_RESTORE_FRAME
+
         retq
 END(ftrace_graph_caller)