ftrace/x86: Move the mcount/fentry code out of entry_64.S
As the mcount code gets more complex, it really does not belong
in the entry.S file. By moving it into its own file "mcount.S"
keeps things a bit cleaner.
Link: http://lkml.kernel.org/p/20140508152152.2130e8cf@gandalf.local.home
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index f4d9600..db7f41d 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -26,6 +26,7 @@
obj-y += probe_roms.o
obj-$(CONFIG_X86_32) += i386_ksyms_32.o
obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o
+obj-$(CONFIG_X86_64) += mcount_64.o
obj-y += syscall_$(BITS).o vsyscall_gtod.o
obj-$(CONFIG_X86_64) += vsyscall_64.o
obj-$(CONFIG_X86_64) += vsyscall_emu_64.o
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 1e96c36..3db806d 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -53,7 +53,6 @@
#include <asm/page_types.h>
#include <asm/irqflags.h>
#include <asm/paravirt.h>
-#include <asm/ftrace.h>
#include <asm/percpu.h>
#include <asm/asm.h>
#include <asm/context_tracking.h>
@@ -69,209 +68,6 @@
.code64
.section .entry.text, "ax"
-#ifdef CONFIG_FUNCTION_TRACER
-
-#ifdef CC_USING_FENTRY
-# define function_hook __fentry__
-#else
-# define function_hook mcount
-#endif
-
-#ifdef CONFIG_DYNAMIC_FTRACE
-
-ENTRY(function_hook)
- retq
-END(function_hook)
-
-/* skip is set if stack has been adjusted */
-.macro ftrace_caller_setup skip=0
- MCOUNT_SAVE_FRAME \skip
-
- /* Load the ftrace_ops into the 3rd parameter */
- movq function_trace_op(%rip), %rdx
-
- /* Load ip into the first parameter */
- movq RIP(%rsp), %rdi
- subq $MCOUNT_INSN_SIZE, %rdi
- /* Load the parent_ip into the second parameter */
-#ifdef CC_USING_FENTRY
- movq SS+16(%rsp), %rsi
-#else
- movq 8(%rbp), %rsi
-#endif
-.endm
-
-ENTRY(ftrace_caller)
- /* Check if tracing was disabled (quick check) */
- cmpl $0, function_trace_stop
- jne ftrace_stub
-
- ftrace_caller_setup
- /* regs go into 4th parameter (but make it NULL) */
- movq $0, %rcx
-
-GLOBAL(ftrace_call)
- call ftrace_stub
-
- MCOUNT_RESTORE_FRAME
-ftrace_return:
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-GLOBAL(ftrace_graph_call)
- jmp ftrace_stub
-#endif
-
-GLOBAL(ftrace_stub)
- retq
-END(ftrace_caller)
-
-ENTRY(ftrace_regs_caller)
- /* Save the current flags before compare (in SS location)*/
- pushfq
-
- /* Check if tracing was disabled (quick check) */
- cmpl $0, function_trace_stop
- jne ftrace_restore_flags
-
- /* skip=8 to skip flags saved in SS */
- ftrace_caller_setup 8
-
- /* Save the rest of pt_regs */
- movq %r15, R15(%rsp)
- movq %r14, R14(%rsp)
- movq %r13, R13(%rsp)
- movq %r12, R12(%rsp)
- movq %r11, R11(%rsp)
- movq %r10, R10(%rsp)
- movq %rbp, RBP(%rsp)
- movq %rbx, RBX(%rsp)
- /* Copy saved flags */
- movq SS(%rsp), %rcx
- movq %rcx, EFLAGS(%rsp)
- /* Kernel segments */
- movq $__KERNEL_DS, %rcx
- movq %rcx, SS(%rsp)
- movq $__KERNEL_CS, %rcx
- movq %rcx, CS(%rsp)
- /* Stack - skipping return address */
- leaq SS+16(%rsp), %rcx
- movq %rcx, RSP(%rsp)
-
- /* regs go into 4th parameter */
- leaq (%rsp), %rcx
-
-GLOBAL(ftrace_regs_call)
- call ftrace_stub
-
- /* Copy flags back to SS, to restore them */
- movq EFLAGS(%rsp), %rax
- movq %rax, SS(%rsp)
-
- /* Handlers can change the RIP */
- movq RIP(%rsp), %rax
- movq %rax, SS+8(%rsp)
-
- /* restore the rest of pt_regs */
- movq R15(%rsp), %r15
- movq R14(%rsp), %r14
- movq R13(%rsp), %r13
- movq R12(%rsp), %r12
- movq R10(%rsp), %r10
- movq RBP(%rsp), %rbp
- movq RBX(%rsp), %rbx
-
- /* skip=8 to skip flags saved in SS */
- MCOUNT_RESTORE_FRAME 8
-
- /* Restore flags */
- popfq
-
- jmp ftrace_return
-ftrace_restore_flags:
- popfq
- jmp ftrace_stub
-
-END(ftrace_regs_caller)
-
-
-#else /* ! CONFIG_DYNAMIC_FTRACE */
-
-ENTRY(function_hook)
- cmpl $0, function_trace_stop
- jne ftrace_stub
-
- cmpq $ftrace_stub, ftrace_trace_function
- jnz trace
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
- cmpq $ftrace_stub, ftrace_graph_return
- jnz ftrace_graph_caller
-
- cmpq $ftrace_graph_entry_stub, ftrace_graph_entry
- jnz ftrace_graph_caller
-#endif
-
-GLOBAL(ftrace_stub)
- retq
-
-trace:
- MCOUNT_SAVE_FRAME
-
- movq RIP(%rsp), %rdi
-#ifdef CC_USING_FENTRY
- movq SS+16(%rsp), %rsi
-#else
- movq 8(%rbp), %rsi
-#endif
- subq $MCOUNT_INSN_SIZE, %rdi
-
- call *ftrace_trace_function
-
- MCOUNT_RESTORE_FRAME
-
- jmp ftrace_stub
-END(function_hook)
-#endif /* CONFIG_DYNAMIC_FTRACE */
-#endif /* CONFIG_FUNCTION_TRACER */
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-ENTRY(ftrace_graph_caller)
- MCOUNT_SAVE_FRAME
-
-#ifdef CC_USING_FENTRY
- leaq SS+16(%rsp), %rdi
- movq $0, %rdx /* No framepointers needed */
-#else
- leaq 8(%rbp), %rdi
- movq (%rbp), %rdx
-#endif
- movq RIP(%rsp), %rsi
- subq $MCOUNT_INSN_SIZE, %rsi
-
- call prepare_ftrace_return
-
- MCOUNT_RESTORE_FRAME
-
- retq
-END(ftrace_graph_caller)
-
-GLOBAL(return_to_handler)
- subq $24, %rsp
-
- /* Save the return values */
- movq %rax, (%rsp)
- movq %rdx, 8(%rsp)
- movq %rbp, %rdi
-
- call ftrace_return_to_handler
-
- movq %rax, %rdi
- movq 8(%rsp), %rdx
- movq (%rsp), %rax
- addq $24, %rsp
- jmp *%rdi
-#endif
-
#ifndef CONFIG_PREEMPT
#define retint_kernel retint_restore_args
diff --git a/arch/x86/kernel/mcount_64.S b/arch/x86/kernel/mcount_64.S
new file mode 100644
index 0000000..c050a01
--- /dev/null
+++ b/arch/x86/kernel/mcount_64.S
@@ -0,0 +1,217 @@
+/*
+ * linux/arch/x86_64/mcount_64.S
+ *
+ * Copyright (C) 2014 Steven Rostedt, Red Hat Inc
+ */
+
+#include <linux/linkage.h>
+#include <asm/ptrace.h>
+#include <asm/ftrace.h>
+
+
+ .code64
+ .section .entry.text, "ax"
+
+
+#ifdef CONFIG_FUNCTION_TRACER
+
+#ifdef CC_USING_FENTRY
+# define function_hook __fentry__
+#else
+# define function_hook mcount
+#endif
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+ENTRY(function_hook)
+ retq
+END(function_hook)
+
+/* skip is set if stack has been adjusted */
+.macro ftrace_caller_setup skip=0
+ MCOUNT_SAVE_FRAME \skip
+
+ /* Load the ftrace_ops into the 3rd parameter */
+ movq function_trace_op(%rip), %rdx
+
+ /* Load ip into the first parameter */
+ movq RIP(%rsp), %rdi
+ subq $MCOUNT_INSN_SIZE, %rdi
+ /* Load the parent_ip into the second parameter */
+#ifdef CC_USING_FENTRY
+ movq SS+16(%rsp), %rsi
+#else
+ movq 8(%rbp), %rsi
+#endif
+.endm
+
+ENTRY(ftrace_caller)
+ /* Check if tracing was disabled (quick check) */
+ cmpl $0, function_trace_stop
+ jne ftrace_stub
+
+ ftrace_caller_setup
+ /* regs go into 4th parameter (but make it NULL) */
+ movq $0, %rcx
+
+GLOBAL(ftrace_call)
+ call ftrace_stub
+
+ MCOUNT_RESTORE_FRAME
+ftrace_return:
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+GLOBAL(ftrace_graph_call)
+ jmp ftrace_stub
+#endif
+
+GLOBAL(ftrace_stub)
+ retq
+END(ftrace_caller)
+
+ENTRY(ftrace_regs_caller)
+ /* Save the current flags before compare (in SS location)*/
+ pushfq
+
+ /* Check if tracing was disabled (quick check) */
+ cmpl $0, function_trace_stop
+ jne ftrace_restore_flags
+
+ /* skip=8 to skip flags saved in SS */
+ ftrace_caller_setup 8
+
+ /* Save the rest of pt_regs */
+ movq %r15, R15(%rsp)
+ movq %r14, R14(%rsp)
+ movq %r13, R13(%rsp)
+ movq %r12, R12(%rsp)
+ movq %r11, R11(%rsp)
+ movq %r10, R10(%rsp)
+ movq %rbp, RBP(%rsp)
+ movq %rbx, RBX(%rsp)
+ /* Copy saved flags */
+ movq SS(%rsp), %rcx
+ movq %rcx, EFLAGS(%rsp)
+ /* Kernel segments */
+ movq $__KERNEL_DS, %rcx
+ movq %rcx, SS(%rsp)
+ movq $__KERNEL_CS, %rcx
+ movq %rcx, CS(%rsp)
+ /* Stack - skipping return address */
+ leaq SS+16(%rsp), %rcx
+ movq %rcx, RSP(%rsp)
+
+ /* regs go into 4th parameter */
+ leaq (%rsp), %rcx
+
+GLOBAL(ftrace_regs_call)
+ call ftrace_stub
+
+ /* Copy flags back to SS, to restore them */
+ movq EFLAGS(%rsp), %rax
+ movq %rax, SS(%rsp)
+
+ /* Handlers can change the RIP */
+ movq RIP(%rsp), %rax
+ movq %rax, SS+8(%rsp)
+
+ /* restore the rest of pt_regs */
+ movq R15(%rsp), %r15
+ movq R14(%rsp), %r14
+ movq R13(%rsp), %r13
+ movq R12(%rsp), %r12
+ movq R10(%rsp), %r10
+ movq RBP(%rsp), %rbp
+ movq RBX(%rsp), %rbx
+
+ /* skip=8 to skip flags saved in SS */
+ MCOUNT_RESTORE_FRAME 8
+
+ /* Restore flags */
+ popfq
+
+ jmp ftrace_return
+ftrace_restore_flags:
+ popfq
+ jmp ftrace_stub
+
+END(ftrace_regs_caller)
+
+
+#else /* ! CONFIG_DYNAMIC_FTRACE */
+
+ENTRY(function_hook)
+ cmpl $0, function_trace_stop
+ jne ftrace_stub
+
+ cmpq $ftrace_stub, ftrace_trace_function
+ jnz trace
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ cmpq $ftrace_stub, ftrace_graph_return
+ jnz ftrace_graph_caller
+
+ cmpq $ftrace_graph_entry_stub, ftrace_graph_entry
+ jnz ftrace_graph_caller
+#endif
+
+GLOBAL(ftrace_stub)
+ retq
+
+trace:
+ MCOUNT_SAVE_FRAME
+
+ movq RIP(%rsp), %rdi
+#ifdef CC_USING_FENTRY
+ movq SS+16(%rsp), %rsi
+#else
+ movq 8(%rbp), %rsi
+#endif
+ subq $MCOUNT_INSN_SIZE, %rdi
+
+ call *ftrace_trace_function
+
+ MCOUNT_RESTORE_FRAME
+
+ jmp ftrace_stub
+END(function_hook)
+#endif /* CONFIG_DYNAMIC_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ENTRY(ftrace_graph_caller)
+ MCOUNT_SAVE_FRAME
+
+#ifdef CC_USING_FENTRY
+ leaq SS+16(%rsp), %rdi
+ movq $0, %rdx /* No framepointers needed */
+#else
+ leaq 8(%rbp), %rdi
+ movq (%rbp), %rdx
+#endif
+ movq RIP(%rsp), %rsi
+ subq $MCOUNT_INSN_SIZE, %rsi
+
+ call prepare_ftrace_return
+
+ MCOUNT_RESTORE_FRAME
+
+ retq
+END(ftrace_graph_caller)
+
+GLOBAL(return_to_handler)
+ subq $24, %rsp
+
+ /* Save the return values */
+ movq %rax, (%rsp)
+ movq %rdx, 8(%rsp)
+ movq %rbp, %rdi
+
+ call ftrace_return_to_handler
+
+ movq %rax, %rdi
+ movq 8(%rsp), %rdx
+ movq (%rsp), %rax
+ addq $24, %rsp
+ jmp *%rdi
+#endif
