1/* 2 * Copyright IBM Corp. 2008, 2009 3 * 4 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>, 5 * 6 */ 7 8#include <linux/linkage.h> 9#include <asm/asm-offsets.h> 10#include <asm/ftrace.h> 11#include <asm/ptrace.h> 12 13 .section .kprobes.text, "ax" 14 15ENTRY(ftrace_stub) 16 br %r14 17 18#define STACK_FRAME_SIZE (STACK_FRAME_OVERHEAD + __PT_SIZE) 19#define STACK_PTREGS (STACK_FRAME_OVERHEAD) 20#define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS) 21#define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW) 22 23ENTRY(_mcount) 24 br %r14 25 26ENTRY(ftrace_caller) 27 .globl ftrace_regs_caller 28 .set ftrace_regs_caller,ftrace_caller 29 lgr %r1,%r15 30#ifndef CC_USING_HOTPATCH 31 aghi %r0,MCOUNT_RETURN_FIXUP 32#endif 33 aghi %r15,-STACK_FRAME_SIZE 34 stg %r1,__SF_BACKCHAIN(%r15) 35 stg %r1,(STACK_PTREGS_GPRS+15*8)(%r15) 36 stg %r0,(STACK_PTREGS_PSW+8)(%r15) 37 stmg %r2,%r14,(STACK_PTREGS_GPRS+2*8)(%r15) 38#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES 39 aghik %r2,%r0,-MCOUNT_INSN_SIZE 40 lgrl %r4,function_trace_op 41 lgrl %r1,ftrace_trace_function 42#else 43 lgr %r2,%r0 44 aghi %r2,-MCOUNT_INSN_SIZE 45 larl %r4,function_trace_op 46 lg %r4,0(%r4) 47 larl %r1,ftrace_trace_function 48 lg %r1,0(%r1) 49#endif 50 lgr %r3,%r14 51 la %r5,STACK_PTREGS(%r15) 52 basr %r14,%r1 53#ifdef CONFIG_FUNCTION_GRAPH_TRACER 54# The j instruction gets runtime patched to a nop instruction. 55# See ftrace_enable_ftrace_graph_caller. 56ENTRY(ftrace_graph_caller) 57 j ftrace_graph_caller_end 58 lg %r2,(STACK_PTREGS_GPRS+14*8)(%r15) 59 lg %r3,(STACK_PTREGS_PSW+8)(%r15) 60 brasl %r14,prepare_ftrace_return 61 stg %r2,(STACK_PTREGS_GPRS+14*8)(%r15) 62ftrace_graph_caller_end: 63 .globl ftrace_graph_caller_end 64#endif 65 lg %r1,(STACK_PTREGS_PSW+8)(%r15) 66 lmg %r2,%r15,(STACK_PTREGS_GPRS+2*8)(%r15) 67 br %r1 68 69#ifdef CONFIG_FUNCTION_GRAPH_TRACER 70 71ENTRY(return_to_handler) 72 stmg %r2,%r5,32(%r15) 73 lgr %r1,%r15 74 aghi %r15,-STACK_FRAME_OVERHEAD 75 stg %r1,__SF_BACKCHAIN(%r15) 76 brasl %r14,ftrace_return_to_handler 77 aghi %r15,STACK_FRAME_OVERHEAD 78 lgr %r14,%r2 79 lmg %r2,%r5,32(%r15) 80 br %r14 81 82#endif 83