56 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			56 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Stack trace management functions
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|  *
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|  * Copyright (C) 2007 Atmel Corporation
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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|  */
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| #include <linux/sched.h>
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| #include <linux/stacktrace.h>
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| #include <linux/thread_info.h>
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| #include <linux/module.h>
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| 
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| register unsigned long current_frame_pointer asm("r7");
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| 
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| struct stackframe {
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| 	unsigned long lr;
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| 	unsigned long fp;
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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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| 	unsigned long low, high;
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| 	unsigned long fp;
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| 	struct stackframe *frame;
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| 	int skip = trace->skip;
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| 
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| 	low = (unsigned long)task_stack_page(current);
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| 	high = low + THREAD_SIZE;
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| 	fp = current_frame_pointer;
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| 
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| 	while (fp >= low && fp <= (high - 8)) {
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| 		frame = (struct stackframe *)fp;
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| 
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| 		if (skip) {
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| 			skip--;
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| 		} else {
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| 			trace->entries[trace->nr_entries++] = frame->lr;
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| 			if (trace->nr_entries >= trace->max_entries)
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| 				break;
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| 		}
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| 
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| 		/*
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| 		 * The next frame must be at a higher address than the
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| 		 * current frame.
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| 		 */
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| 		low = fp + 8;
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| 		fp = frame->fp;
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| 	}
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| }
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| EXPORT_SYMBOL_GPL(save_stack_trace);
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