| /* | |
| * Copyright IBM Corp. 2008, 2009 | |
| * | |
| * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>, | |
| * | |
| */ | |
| #include <linux/linkage.h> | |
| #include <asm/asm-offsets.h> | |
| #include <asm/ftrace.h> | |
| .section .kprobes.text, "ax" | |
| ENTRY(ftrace_stub) | |
| br %r14 | |
| ENTRY(_mcount) | |
| #ifdef CONFIG_DYNAMIC_FTRACE | |
| br %r14 | |
| ENTRY(ftrace_caller) | |
| #endif | |
| stm %r2,%r5,16(%r15) | |
| bras %r1,2f | |
| 0: .long ftrace_trace_function | |
| 1: .long function_trace_stop | |
| 2: l %r2,1b-0b(%r1) | |
| icm %r2,0xf,0(%r2) | |
| jnz 3f | |
| st %r14,56(%r15) | |
| lr %r0,%r15 | |
| ahi %r15,-96 | |
| l %r3,100(%r15) | |
| la %r2,0(%r14) | |
| st %r0,__SF_BACKCHAIN(%r15) | |
| la %r3,0(%r3) | |
| ahi %r2,-MCOUNT_INSN_SIZE | |
| l %r14,0b-0b(%r1) | |
| l %r14,0(%r14) | |
| basr %r14,%r14 | |
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
| l %r2,100(%r15) | |
| l %r3,152(%r15) | |
| ENTRY(ftrace_graph_caller) | |
| # The bras instruction gets runtime patched to call prepare_ftrace_return. | |
| # See ftrace_enable_ftrace_graph_caller. The patched instruction is: | |
| # bras %r14,prepare_ftrace_return | |
| bras %r14,0f | |
| 0: st %r2,100(%r15) | |
| #endif | |
| ahi %r15,96 | |
| l %r14,56(%r15) | |
| 3: lm %r2,%r5,16(%r15) | |
| br %r14 | |
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
| ENTRY(return_to_handler) | |
| stm %r2,%r5,16(%r15) | |
| st %r14,56(%r15) | |
| lr %r0,%r15 | |
| ahi %r15,-96 | |
| st %r0,__SF_BACKCHAIN(%r15) | |
| bras %r1,0f | |
| .long ftrace_return_to_handler | |
| 0: l %r2,0b-0b(%r1) | |
| basr %r14,%r2 | |
| lr %r14,%r2 | |
| ahi %r15,96 | |
| lm %r2,%r5,16(%r15) | |
| br %r14 | |
| #endif |