1/* 2 * Copyright IBM Corp. 2008, 2009 3 * 4 * Author(s): Heiko Carstens <[email protected]>, 5 * 6 */ 7 8#include <linux/linkage.h> 9#include <asm/asm-offsets.h> 10#include <asm/ftrace.h> 11 12 .section .kprobes.text, "ax" 13 14ENTRY(ftrace_stub) 15 br %r14 16 17ENTRY(_mcount) 18#ifdef CONFIG_DYNAMIC_FTRACE 19 br %r14 20 21ENTRY(ftrace_caller) 22#endif 23 stm %r2,%r5,16(%r15) 24 bras %r1,2f 250: .long ftrace_trace_function 261: .long function_trace_stop 272: l %r2,1b-0b(%r1) 28 icm %r2,0xf,0(%r2) 29 jnz 3f 30 st %r14,56(%r15) 31 lr %r0,%r15 32 ahi %r15,-96 33 l %r3,100(%r15) 34 la %r2,0(%r14) 35 st %r0,__SF_BACKCHAIN(%r15) 36 la %r3,0(%r3) 37 ahi %r2,-MCOUNT_INSN_SIZE 38 l %r14,0b-0b(%r1) 39 l %r14,0(%r14) 40 basr %r14,%r14 41#ifdef CONFIG_FUNCTION_GRAPH_TRACER 42 l %r2,100(%r15) 43 l %r3,152(%r15) 44ENTRY(ftrace_graph_caller) 45# The bras instruction gets runtime patched to call prepare_ftrace_return. 46# See ftrace_enable_ftrace_graph_caller. The patched instruction is: 47# bras %r14,prepare_ftrace_return 48 bras %r14,0f 490: st %r2,100(%r15) 50#endif 51 ahi %r15,96 52 l %r14,56(%r15) 533: lm %r2,%r5,16(%r15) 54 br %r14 55 56#ifdef CONFIG_FUNCTION_GRAPH_TRACER 57 58ENTRY(return_to_handler) 59 stm %r2,%r5,16(%r15) 60 st %r14,56(%r15) 61 lr %r0,%r15 62 ahi %r15,-96 63 st %r0,__SF_BACKCHAIN(%r15) 64 bras %r1,0f 65 .long ftrace_return_to_handler 660: l %r2,0b-0b(%r1) 67 basr %r14,%r2 68 lr %r14,%r2 69 ahi %r15,96 70 lm %r2,%r5,16(%r15) 71 br %r14 72 73#endif 74