1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright IBM Corp. 2008, 2009
5 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
9 #include <linux/linkage.h>
10 #include <asm/asm-offsets.h>
11 #include <asm/ftrace.h>
12 #include <asm/nospec-insn.h>
13 #include <asm/ptrace.h>
14 #include <asm/export.h>
19 .section .kprobes.text, "ax"
24 #define STACK_FRAME_SIZE (STACK_FRAME_OVERHEAD + __PT_SIZE)
25 #define STACK_PTREGS (STACK_FRAME_OVERHEAD)
26 #define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS)
27 #define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW)
29 /* allocate just enough for r14, r15 and backchain */
30 #define TRACED_FUNC_FRAME_SIZE 24
32 #define TRACED_FUNC_FRAME_SIZE STACK_FRAME_OVERHEAD
38 EXPORT_SYMBOL(_mcount)
41 .globl ftrace_regs_caller
42 .set ftrace_regs_caller,ftrace_caller
43 stg %r14,(__SF_GPRS+8*8)(%r15) # save traced function caller
45 #if !(defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT))
46 aghi %r0,MCOUNT_RETURN_FIXUP
48 # allocate stack frame for ftrace_caller to contain traced function
49 aghi %r15,-TRACED_FUNC_FRAME_SIZE
50 stg %r1,__SF_BACKCHAIN(%r15)
51 stg %r0,(__SF_GPRS+8*8)(%r15)
52 stg %r15,(__SF_GPRS+9*8)(%r15)
53 # allocate pt_regs and stack frame for ftrace_trace_function
54 aghi %r15,-STACK_FRAME_SIZE
55 stg %r1,(STACK_PTREGS_GPRS+15*8)(%r15)
56 aghi %r1,-TRACED_FUNC_FRAME_SIZE
57 stg %r1,__SF_BACKCHAIN(%r15)
58 stg %r0,(STACK_PTREGS_PSW+8)(%r15)
59 stmg %r2,%r14,(STACK_PTREGS_GPRS+2*8)(%r15)
60 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
61 aghik %r2,%r0,-MCOUNT_INSN_SIZE
62 lgrl %r4,function_trace_op
66 aghi %r2,-MCOUNT_INSN_SIZE
67 larl %r4,function_trace_op
73 la %r5,STACK_PTREGS(%r15)
75 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
76 # The j instruction gets runtime patched to a nop instruction.
77 # See ftrace_enable_ftrace_graph_caller.
78 ENTRY(ftrace_graph_caller)
79 j ftrace_graph_caller_end
80 lg %r2,(STACK_PTREGS_GPRS+14*8)(%r15)
81 lg %r3,(STACK_PTREGS_PSW+8)(%r15)
82 brasl %r14,prepare_ftrace_return
83 stg %r2,(STACK_PTREGS_GPRS+14*8)(%r15)
84 ftrace_graph_caller_end:
85 .globl ftrace_graph_caller_end
87 lg %r1,(STACK_PTREGS_PSW+8)(%r15)
88 lmg %r2,%r15,(STACK_PTREGS_GPRS+2*8)(%r15)
91 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
93 ENTRY(return_to_handler)
96 aghi %r15,-STACK_FRAME_OVERHEAD
97 stg %r1,__SF_BACKCHAIN(%r15)
98 brasl %r14,ftrace_return_to_handler
99 aghi %r15,STACK_FRAME_OVERHEAD