/* * Stack trace utility for OpenRISC * * Copyright (C) 2017 Stafford Horne <shorne@gmail.com> * * This file is licensed under the terms of the GNU General Public License * version 2.  This program is licensed "as is" without any warranty of any * kind, whether express or implied. * * Losely based on work from sh and powerpc. */ #include <linux/export.h>#include <linux/sched.h>#include <linux/sched/debug.h>#include <linux/sched/task_stack.h>#include <linux/stacktrace.h> #include <asm/processor.h>#include <asm/unwinder.h> /* * Save stack-backtrace addresses into a stack_trace buffer. */static voidsave_stack_address(void *data, unsigned long addr, int reliable){	struct stack_trace *trace = data; 	if (!reliable)		return; 	if (trace->skip > 0) {		trace->skip--;		return;	} 	if (trace->nr_entries < trace->max_entries)		trace->entries[trace->nr_entries++] = addr;} void save_stack_trace(struct stack_trace *trace){	unwind_stack(trace, (unsigned long *) &trace, save_stack_address);}EXPORT_SYMBOL_GPL(save_stack_trace); static voidsave_stack_address_nosched(void *data, unsigned long addr, int reliable){	struct stack_trace *trace = (struct stack_trace *)data; 	if (!reliable)		return; 	if (in_sched_functions(addr))		return; 	if (trace->skip > 0) {		trace->skip--;		return;	} 	if (trace->nr_entries < trace->max_entries)		trace->entries[trace->nr_entries++] = addr;} void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace){	unsigned long *sp = NULL; 	if (!try_get_task_stack(tsk))		return; 	if (tsk == current)		sp = (unsigned long *) &sp;	else {		unsigned long ksp; 		/* Locate stack from kernel context */		ksp = task_thread_info(tsk)->ksp;		ksp += STACK_FRAME_OVERHEAD;	/* redzone */		ksp += sizeof(struct pt_regs); 		sp = (unsigned long *) ksp;	} 	unwind_stack(trace, sp, save_stack_address_nosched); 	put_task_stack(tsk);}EXPORT_SYMBOL_GPL(save_stack_trace_tsk); voidsave_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace){	unwind_stack(trace, (unsigned long *) regs->sp,		     save_stack_address_nosched);}EXPORT_SYMBOL_GPL(save_stack_trace_regs);