1 files changed, 103 insertions, 54 deletions

diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h
index 68d362f8d6c1..185331e91f83 100644
--- a/arch/s390/include/asm/ftrace.h
+++ b/arch/s390/include/asm/ftrace.h
@@ -3,91 +3,108 @@
 #define _ASM_S390_FTRACE_H
 
 #define ARCH_SUPPORTS_FTRACE_OPS 1
-
-#if defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT)
 #define MCOUNT_INSN_SIZE	6
-#else
-#define MCOUNT_INSN_SIZE	24
-#define MCOUNT_RETURN_FIXUP	18
-#endif
-
-#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
 
 #ifndef __ASSEMBLY__
+#include <asm/stacktrace.h>
 
-#ifdef CONFIG_CC_IS_CLANG
-/* https://bugs.llvm.org/show_bug.cgi?id=41424 */
-#define ftrace_return_address(n) 0UL
-#else
-#define ftrace_return_address(n) __builtin_return_address(n)
-#endif
+static __always_inline unsigned long return_address(unsigned int n)
+{
+	struct stack_frame *sf;
+
+	if (!n)
+		return (unsigned long)__builtin_return_address(0);
+
+	sf = (struct stack_frame *)current_frame_address();
+	do {
+		sf = (struct stack_frame *)sf->back_chain;
+		if (!sf)
+			return 0;
+	} while (--n);
+	return sf->gprs[8];
+}
+#define ftrace_return_address(n) return_address(n)
 
-void _mcount(void);
 void ftrace_caller(void);
 
-extern char ftrace_graph_caller_end;
-extern unsigned long ftrace_plt;
+extern void *ftrace_func;
 
 struct dyn_arch_ftrace { };
 
-#define MCOUNT_ADDR ((unsigned long)_mcount)
+#define MCOUNT_ADDR 0
 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
 
 #define KPROBE_ON_FTRACE_NOP	0
 #define KPROBE_ON_FTRACE_CALL	1
 
+struct module;
+struct dyn_ftrace;
+struct ftrace_ops;
+
+bool ftrace_need_init_nop(void);
+#define ftrace_need_init_nop ftrace_need_init_nop
+
+int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec);
+#define ftrace_init_nop ftrace_init_nop
+
 static inline unsigned long ftrace_call_adjust(unsigned long addr)
 {
 	return addr;
 }
+#define ftrace_get_symaddr(fentry_ip) ((unsigned long)(fentry_ip))
 
-struct ftrace_insn {
-	u16 opc;
-	s32 disp;
-} __packed;
+#include <linux/ftrace_regs.h>
 
-static inline void ftrace_generate_nop_insn(struct ftrace_insn *insn)
+static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs)
 {
-#ifdef CONFIG_FUNCTION_TRACER
-#if defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT)
-	/* brcl 0,0 */
-	insn->opc = 0xc004;
-	insn->disp = 0;
-#else
-	/* jg .+24 */
-	insn->opc = 0xc0f4;
-	insn->disp = MCOUNT_INSN_SIZE / 2;
-#endif
-#endif
+	struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs;
+
+	if (test_pt_regs_flag(regs, PIF_FTRACE_FULL_REGS))
+		return regs;
+	return NULL;
 }
 
-static inline int is_ftrace_nop(struct ftrace_insn *insn)
+static __always_inline void
+ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs,
+				    unsigned long ip)
 {
-#ifdef CONFIG_FUNCTION_TRACER
-#if defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT)
-	if (insn->disp == 0)
-		return 1;
-#else
-	if (insn->disp == MCOUNT_INSN_SIZE / 2)
-		return 1;
-#endif
-#endif
-	return 0;
+	arch_ftrace_regs(fregs)->regs.psw.addr = ip;
 }
 
-static inline void ftrace_generate_call_insn(struct ftrace_insn *insn,
-					     unsigned long ip)
+#undef ftrace_regs_get_frame_pointer
+static __always_inline unsigned long
+ftrace_regs_get_frame_pointer(struct ftrace_regs *fregs)
 {
-#ifdef CONFIG_FUNCTION_TRACER
-	unsigned long target;
+	return ftrace_regs_get_stack_pointer(fregs);
+}
 
-	/* brasl r0,ftrace_caller */
-	target = is_module_addr((void *) ip) ? ftrace_plt : FTRACE_ADDR;
-	insn->opc = 0xc005;
-	insn->disp = (target - ip) / 2;
-#endif
+static __always_inline unsigned long
+ftrace_regs_get_return_address(const struct ftrace_regs *fregs)
+{
+	return arch_ftrace_regs(fregs)->regs.gprs[14];
 }
 
+#define arch_ftrace_fill_perf_regs(fregs, _regs)	 do {		\
+		(_regs)->psw.mask = 0;					\
+		(_regs)->psw.addr = arch_ftrace_regs(fregs)->regs.psw.addr;		\
+		(_regs)->gprs[15] = arch_ftrace_regs(fregs)->regs.gprs[15];		\
+	} while (0)
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+/*
+ * When an ftrace registered caller is tracing a function that is
+ * also set by a register_ftrace_direct() call, it needs to be
+ * differentiated in the ftrace_caller trampoline. To do this,
+ * place the direct caller in the ORIG_GPR2 part of pt_regs. This
+ * tells the ftrace_caller that there's a direct caller.
+ */
+static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs, unsigned long addr)
+{
+	struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs;
+	regs->orig_gpr2 = addr;
+}
+#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
+
 /*
  * Even though the system call numbers are identical for s390/s390x a
  * different system call table is used for compat tasks. This may lead
@@ -113,5 +130,37 @@ static inline bool arch_syscall_match_sym_name(const char *sym,
 	return !strcmp(sym + 7, name) || !strcmp(sym + 8, name);
 }
 
+void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
+		       struct ftrace_ops *op, struct ftrace_regs *fregs);
+#define ftrace_graph_func ftrace_graph_func
+
 #endif /* __ASSEMBLY__ */
+
+#ifdef CONFIG_FUNCTION_TRACER
+
+#define FTRACE_NOP_INSN .word 0xc004, 0x0000, 0x0000 /* brcl 0,0 */
+
+#ifndef CC_USING_HOTPATCH
+
+#define FTRACE_GEN_MCOUNT_RECORD(name)		\
+	.section __mcount_loc, "a", @progbits;	\
+	.quad name;				\
+	.previous;
+
+#else /* !CC_USING_HOTPATCH */
+
+#define FTRACE_GEN_MCOUNT_RECORD(name)
+
+#endif /* !CC_USING_HOTPATCH */
+
+#define FTRACE_GEN_NOP_ASM(name)		\
+	FTRACE_GEN_MCOUNT_RECORD(name)		\
+	FTRACE_NOP_INSN
+
+#else /* CONFIG_FUNCTION_TRACER */
+
+#define FTRACE_GEN_NOP_ASM(name)
+
+#endif /* CONFIG_FUNCTION_TRACER */
+
 #endif /* _ASM_S390_FTRACE_H */