64 lines
		
	
	
	
		
			1.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			64 lines
		
	
	
	
		
			1.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
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								/*
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								 * Stack trace management functions
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								 *
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								 *  Copyright (C) 2009 Helge Deller <deller@gmx.de>
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								 *  based on arch/x86/kernel/stacktrace.c by Ingo Molnar <mingo@redhat.com>
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								 *  and parisc unwind functions by Randolph Chung <tausq@debian.org>
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								 *
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								 *  TODO: Userspace stacktrace (CONFIG_USER_STACKTRACE_SUPPORT)
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								 */
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								#include <linux/module.h>
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								#include <linux/stacktrace.h>
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								#include <asm/unwind.h>
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								static void dump_trace(struct task_struct *task, struct stack_trace *trace)
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								{
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									struct unwind_frame_info info;
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									/* initialize unwind info */
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									if (task == current) {
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										unsigned long sp;
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										struct pt_regs r;
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								HERE:
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										asm volatile ("copy %%r30, %0" : "=r"(sp));
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										memset(&r, 0, sizeof(struct pt_regs));
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										r.iaoq[0] = (unsigned long)&&HERE;
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										r.gr[2] = (unsigned long)__builtin_return_address(0);
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										r.gr[30] = sp;
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										unwind_frame_init(&info, task, &r);
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									} else {
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										unwind_frame_init_from_blocked_task(&info, task);
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									}
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									/* unwind stack and save entries in stack_trace struct */
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									trace->nr_entries = 0;
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									while (trace->nr_entries < trace->max_entries) {
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										if (unwind_once(&info) < 0 || info.ip == 0)
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											break;
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										if (__kernel_text_address(info.ip))
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											trace->entries[trace->nr_entries++] = info.ip;
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									}
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								}
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								/*
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								 * Save stack-backtrace addresses into a stack_trace buffer.
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								 */
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								void save_stack_trace(struct stack_trace *trace)
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								{
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									dump_trace(current, trace);
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									if (trace->nr_entries < trace->max_entries)
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										trace->entries[trace->nr_entries++] = ULONG_MAX;
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								}
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								EXPORT_SYMBOL_GPL(save_stack_trace);
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								void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
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								{
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									dump_trace(tsk, trace);
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									if (trace->nr_entries < trace->max_entries)
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										trace->entries[trace->nr_entries++] = ULONG_MAX;
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								}
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								EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
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