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