/* SPDX-License-Identifier: GPL-2.0 */ /* * Copyright IBM Corp. 2008, 2009 * * Author(s): Heiko Carstens , * */ #include #include #include #include #include #include GEN_BR_THUNK %r1 GEN_BR_THUNK %r14 .section .kprobes.text, "ax" ENTRY(ftrace_stub) BR_EX %r14 ENDPROC(ftrace_stub) #define STACK_FRAME_SIZE (STACK_FRAME_OVERHEAD + __PT_SIZE) #define STACK_PTREGS (STACK_FRAME_OVERHEAD) #define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS) #define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW) #ifdef __PACK_STACK /* allocate just enough for r14, r15 and backchain */ #define TRACED_FUNC_FRAME_SIZE 24 #else #define TRACED_FUNC_FRAME_SIZE STACK_FRAME_OVERHEAD #endif ENTRY(_mcount) BR_EX %r14 ENDPROC(_mcount) EXPORT_SYMBOL(_mcount) ENTRY(ftrace_caller) .globl ftrace_regs_caller .set ftrace_regs_caller,ftrace_caller stg %r14,(__SF_GPRS+8*8)(%r15) # save traced function caller lghi %r14,0 # save condition code ipm %r14 # don't put any instructions sllg %r14,%r14,16 # clobbering CC before this point lgr %r1,%r15 #if !(defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT)) aghi %r0,MCOUNT_RETURN_FIXUP #endif # allocate stack frame for ftrace_caller to contain traced function aghi %r15,-TRACED_FUNC_FRAME_SIZE stg %r1,__SF_BACKCHAIN(%r15) stg %r0,(__SF_GPRS+8*8)(%r15) stg %r15,(__SF_GPRS+9*8)(%r15) # allocate pt_regs and stack frame for ftrace_trace_function aghi %r15,-STACK_FRAME_SIZE stg %r1,(STACK_PTREGS_GPRS+15*8)(%r15) stg %r14,(STACK_PTREGS_PSW)(%r15) lg %r14,(__SF_GPRS+8*8)(%r1) # restore original return address stosm (STACK_PTREGS_PSW)(%r15),0 aghi %r1,-TRACED_FUNC_FRAME_SIZE stg %r1,__SF_BACKCHAIN(%r15) stg %r0,(STACK_PTREGS_PSW+8)(%r15) stmg %r2,%r14,(STACK_PTREGS_GPRS+2*8)(%r15) #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES aghik %r2,%r0,-MCOUNT_INSN_SIZE lgrl %r4,function_trace_op lgrl %r1,ftrace_trace_function #else lgr %r2,%r0 aghi %r2,-MCOUNT_INSN_SIZE larl %r4,function_trace_op lg %r4,0(%r4) larl %r1,ftrace_trace_function lg %r1,0(%r1) #endif lgr %r3,%r14 la %r5,STACK_PTREGS(%r15) BASR_EX %r14,%r1 #ifdef CONFIG_FUNCTION_GRAPH_TRACER # The j instruction gets runtime patched to a nop instruction. # See ftrace_enable_ftrace_graph_caller. .globl ftrace_graph_caller ftrace_graph_caller: j ftrace_graph_caller_end lmg %r2,%r3,(STACK_PTREGS_GPRS+14*8)(%r15) lg %r4,(STACK_PTREGS_PSW+8)(%r15) brasl %r14,prepare_ftrace_return stg %r2,(STACK_PTREGS_GPRS+14*8)(%r15) ftrace_graph_caller_end: .globl ftrace_graph_caller_end #endif lg %r1,(STACK_PTREGS_PSW+8)(%r15) lmg %r2,%r15,(STACK_PTREGS_GPRS+2*8)(%r15) BR_EX %r1 ENDPROC(ftrace_caller) #ifdef CONFIG_FUNCTION_GRAPH_TRACER ENTRY(return_to_handler) stmg %r2,%r5,32(%r15) lgr %r1,%r15 aghi %r15,-STACK_FRAME_OVERHEAD stg %r1,__SF_BACKCHAIN(%r15) brasl %r14,ftrace_return_to_handler aghi %r15,STACK_FRAME_OVERHEAD lgr %r14,%r2 lmg %r2,%r5,32(%r15) BR_EX %r14 ENDPROC(return_to_handler) #endif