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#include <asm/export.h> 13 14 .section .kprobes.text, "ax" 15 16ENTRY(ftrace_stub) 17 br %r14 18 19#define STACK_FRAME_SIZE (STACK_FRAME_OVERHEAD + __PT_SIZE) 20#define STACK_PTREGS (STACK_FRAME_OVERHEAD) 21#define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS) 22#define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW) 23 24ENTRY(_mcount) 25 br %r14 26 27EXPORT_SYMBOL(_mcount) 28 29ENTRY(ftrace_caller) 30 .globl ftrace_regs_caller 31 .set ftrace_regs_caller,ftrace_caller 32 lgr %r1,%r15 33#ifndef CC_USING_HOTPATCH 34 aghi %r0,MCOUNT_RETURN_FIXUP 35#endif 36 aghi %r15,-STACK_FRAME_SIZE 37 stg %r1,__SF_BACKCHAIN(%r15) 38 stg %r1,(STACK_PTREGS_GPRS+15*8)(%r15) 39 stg %r0,(STACK_PTREGS_PSW+8)(%r15) 40 stmg %r2,%r14,(STACK_PTREGS_GPRS+2*8)(%r15) 41#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES 42 aghik %r2,%r0,-MCOUNT_INSN_SIZE 43 lgrl %r4,function_trace_op 44 lgrl %r1,ftrace_trace_function 45#else 46 lgr %r2,%r0 47 aghi %r2,-MCOUNT_INSN_SIZE 48 larl %r4,function_trace_op 49 lg %r4,0(%r4) 50 larl %r1,ftrace_trace_function 51 lg %r1,0(%r1) 52#endif 53 lgr %r3,%r14 54 la %r5,STACK_PTREGS(%r15) 55 basr %r14,%r1 56#ifdef CONFIG_FUNCTION_GRAPH_TRACER 57# The j instruction gets runtime patched to a nop instruction. 58# See ftrace_enable_ftrace_graph_caller. 59ENTRY(ftrace_graph_caller) 60 j ftrace_graph_caller_end 61 lg %r2,(STACK_PTREGS_GPRS+14*8)(%r15) 62 lg %r3,(STACK_PTREGS_PSW+8)(%r15) 63 brasl %r14,prepare_ftrace_return 64 stg %r2,(STACK_PTREGS_GPRS+14*8)(%r15) 65ftrace_graph_caller_end: 66 .globl ftrace_graph_caller_end 67#endif 68 lg %r1,(STACK_PTREGS_PSW+8)(%r15) 69 lmg %r2,%r15,(STACK_PTREGS_GPRS+2*8)(%r15) 70 br %r1 71 72#ifdef CONFIG_FUNCTION_GRAPH_TRACER 73 74ENTRY(return_to_handler) 75 stmg %r2,%r5,32(%r15) 76 lgr %r1,%r15 77 aghi %r15,-STACK_FRAME_OVERHEAD 78 stg %r1,__SF_BACKCHAIN(%r15) 79 brasl %r14,ftrace_return_to_handler 80 aghi %r15,STACK_FRAME_OVERHEAD 81 lgr %r14,%r2 82 lmg %r2,%r5,32(%r15) 83 br %r14 84 85#endif 86