diff options
Diffstat (limited to 'arch/s390/kernel/mcount.S')
| -rw-r--r-- | arch/s390/kernel/mcount.S | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S new file mode 100644 index 000000000..4786bfe02 --- /dev/null +++ b/arch/s390/kernel/mcount.S @@ -0,0 +1,167 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright IBM Corp. 2008, 2009 + * + */ + +#include <linux/linkage.h> +#include <asm/asm-offsets.h> +#include <asm/ftrace.h> +#include <asm/nospec-insn.h> +#include <asm/ptrace.h> +#include <asm/export.h> + + +#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) +#define STACK_PTREGS_ORIG_GPR2 (STACK_PTREGS + __PT_ORIG_GPR2) +#define STACK_PTREGS_FLAGS (STACK_PTREGS + __PT_FLAGS) +/* packed stack: allocate just enough for r14, r15 and backchain */ +#define TRACED_FUNC_FRAME_SIZE 24 + +#ifdef CONFIG_FUNCTION_TRACER + + GEN_BR_THUNK %r1 + GEN_BR_THUNK %r14 + + .section .kprobes.text, "ax" + +ENTRY(ftrace_stub) + BR_EX %r14 +ENDPROC(ftrace_stub) + + .macro ftrace_regs_entry, allregs=0 + stg %r14,(__SF_GPRS+8*8)(%r15) # save traced function caller + + .if \allregs == 1 + # save psw mask + # don't put any instructions clobbering CC before this point + epsw %r1,%r14 + risbg %r14,%r1,0,31,32 + .endif + + lgr %r1,%r15 + # 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) + xc STACK_PTREGS_ORIG_GPR2(8,%r15),STACK_PTREGS_ORIG_GPR2(%r15) + + .if \allregs == 1 + stg %r14,(STACK_PTREGS_PSW)(%r15) + mvghi STACK_PTREGS_FLAGS(%r15),_PIF_FTRACE_FULL_REGS + .else + xc STACK_PTREGS_FLAGS(8,%r15),STACK_PTREGS_FLAGS(%r15) + .endif + + lg %r14,(__SF_GPRS+8*8)(%r1) # restore original return address + 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) + .endm + +SYM_CODE_START(ftrace_regs_caller) + ftrace_regs_entry 1 + j ftrace_common +SYM_CODE_END(ftrace_regs_caller) + +SYM_CODE_START(ftrace_caller) + ftrace_regs_entry 0 + j ftrace_common +SYM_CODE_END(ftrace_caller) + +SYM_CODE_START(ftrace_common) +#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES + aghik %r2,%r0,-MCOUNT_INSN_SIZE + lgrl %r4,function_trace_op + lgrl %r1,ftrace_func +#else + lgr %r2,%r0 + aghi %r2,-MCOUNT_INSN_SIZE + larl %r4,function_trace_op + lg %r4,0(%r4) + larl %r1,ftrace_func + 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. +SYM_INNER_LABEL(ftrace_graph_caller, SYM_L_GLOBAL) + j .Lftrace_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) +.Lftrace_graph_caller_end: +#endif + lg %r0,(STACK_PTREGS_PSW+8)(%r15) +#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES + ltg %r1,STACK_PTREGS_ORIG_GPR2(%r15) + locgrz %r1,%r0 +#else + lg %r1,STACK_PTREGS_ORIG_GPR2(%r15) + ltgr %r1,%r1 + jnz 0f + lgr %r1,%r0 +#endif +0: lmg %r2,%r15,(STACK_PTREGS_GPRS+2*8)(%r15) + BR_EX %r1 +SYM_CODE_END(ftrace_common) + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + +SYM_FUNC_START(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 +SYM_FUNC_END(return_to_handler) + +#endif +#endif /* CONFIG_FUNCTION_TRACER */ + +#ifdef CONFIG_KPROBES + +SYM_FUNC_START(__kretprobe_trampoline) + + stg %r14,(__SF_GPRS+8*8)(%r15) + lay %r15,-STACK_FRAME_SIZE(%r15) + stmg %r0,%r14,STACK_PTREGS_GPRS(%r15) + + # store original stack pointer in backchain and pt_regs + lay %r7,STACK_FRAME_SIZE(%r15) + stg %r7,__SF_BACKCHAIN(%r15) + stg %r7,STACK_PTREGS_GPRS+(15*8)(%r15) + + # store full psw + epsw %r2,%r3 + risbg %r3,%r2,0,31,32 + stg %r3,STACK_PTREGS_PSW(%r15) + larl %r1,__kretprobe_trampoline + stg %r1,STACK_PTREGS_PSW+8(%r15) + + lay %r2,STACK_PTREGS(%r15) + brasl %r14,trampoline_probe_handler + + mvc __SF_EMPTY(16,%r7),STACK_PTREGS_PSW(%r15) + lmg %r0,%r15,STACK_PTREGS_GPRS(%r15) + lpswe __SF_EMPTY(%r15) + +SYM_FUNC_END(__kretprobe_trampoline) + +#endif /* CONFIG_KPROBES */ |