1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * arch/sh/kernel/stacktrace.c 4 * 5 * Stack trace management functions 6 * 7 * Copyright (C) 2006 - 2008 Paul Mundt 8 */ 9 #include <linux/sched.h> 10 #include <linux/sched/debug.h> 11 #include <linux/stacktrace.h> 12 #include <linux/thread_info.h> 13 #include <linux/module.h> 14 #include <asm/unwinder.h> 15 #include <asm/ptrace.h> 16 #include <asm/stacktrace.h> 17 18 /* 19 * Save stack-backtrace addresses into a stack_trace buffer. 20 */ 21 static void save_stack_address(void *data, unsigned long addr, int reliable) 22 { 23 struct stack_trace *trace = data; 24 25 if (!reliable) 26 return; 27 28 if (trace->skip > 0) { 29 trace->skip--; 30 return; 31 } 32 33 if (trace->nr_entries < trace->max_entries) 34 trace->entries[trace->nr_entries++] = addr; 35 } 36 37 static const struct stacktrace_ops save_stack_ops = { 38 .address = save_stack_address, 39 }; 40 41 void save_stack_trace(struct stack_trace *trace) 42 { 43 unsigned long *sp = (unsigned long *)current_stack_pointer; 44 45 unwind_stack(current, NULL, sp, &save_stack_ops, trace); 46 } 47 EXPORT_SYMBOL_GPL(save_stack_trace); 48 49 static void 50 save_stack_address_nosched(void *data, unsigned long addr, int reliable) 51 { 52 struct stack_trace *trace = (struct stack_trace *)data; 53 54 if (!reliable) 55 return; 56 57 if (in_sched_functions(addr)) 58 return; 59 60 if (trace->skip > 0) { 61 trace->skip--; 62 return; 63 } 64 65 if (trace->nr_entries < trace->max_entries) 66 trace->entries[trace->nr_entries++] = addr; 67 } 68 69 static const struct stacktrace_ops save_stack_ops_nosched = { 70 .address = save_stack_address_nosched, 71 }; 72 73 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) 74 { 75 unsigned long *sp = (unsigned long *)tsk->thread.sp; 76 77 unwind_stack(current, NULL, sp, &save_stack_ops_nosched, trace); 78 } 79 EXPORT_SYMBOL_GPL(save_stack_trace_tsk); 80