103 lines
		
	
	
	
		
			2.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			103 lines
		
	
	
	
		
			2.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | #include <linux/kernel.h>
 | ||
|  | 
 | ||
|  | typedef unsigned int instr; | ||
|  | 
 | ||
|  | #define MAJOR_OP	0xfc000000
 | ||
|  | #define LDA_OP		0x20000000
 | ||
|  | #define STQ_OP		0xb4000000
 | ||
|  | #define BR_OP		0xc0000000
 | ||
|  | 
 | ||
|  | #define STK_ALLOC_1	0x23de8000 /* lda $30,-X($30) */
 | ||
|  | #define STK_ALLOC_1M	0xffff8000
 | ||
|  | #define STK_ALLOC_2	0x43c0153e /* subq $30,X,$30 */
 | ||
|  | #define STK_ALLOC_2M	0xffe01fff
 | ||
|  | 
 | ||
|  | #define MEM_REG		0x03e00000
 | ||
|  | #define MEM_BASE	0x001f0000
 | ||
|  | #define MEM_OFF		0x0000ffff
 | ||
|  | #define MEM_OFF_SIGN	0x00008000
 | ||
|  | #define	BASE_SP		0x001e0000
 | ||
|  | 
 | ||
|  | #define STK_ALLOC_MATCH(INSTR)			\
 | ||
|  |   (((INSTR) & STK_ALLOC_1M) == STK_ALLOC_1	\ | ||
|  |    || ((INSTR) & STK_ALLOC_2M) == STK_ALLOC_2) | ||
|  | #define STK_PUSH_MATCH(INSTR) \
 | ||
|  |   (((INSTR) & (MAJOR_OP | MEM_BASE | MEM_OFF_SIGN)) == (STQ_OP | BASE_SP)) | ||
|  | #define MEM_OP_OFFSET(INSTR) \
 | ||
|  |   (((long)((INSTR) & MEM_OFF) << 48) >> 48) | ||
|  | #define MEM_OP_REG(INSTR) \
 | ||
|  |   (((INSTR) & MEM_REG) >> 22) | ||
|  | 
 | ||
|  | /* Branches, jumps, PAL calls, and illegal opcodes end a basic block. */ | ||
|  | #define BB_END(INSTR)						\
 | ||
|  |   (((instr)(INSTR) >= BR_OP) | ((instr)(INSTR) < LDA_OP) |	\ | ||
|  |    ((((instr)(INSTR) ^ 0x60000000) < 0x20000000) &		\ | ||
|  |     (((instr)(INSTR) & 0x0c000000) != 0))) | ||
|  | 
 | ||
|  | #define IS_KERNEL_TEXT(PC) ((unsigned long)(PC) > START_ADDR)
 | ||
|  | 
 | ||
|  | static char reg_name[][4] = { | ||
|  | 	"v0 ", "t0 ", "t1 ", "t2 ", "t3 ", "t4 ", "t5 ", "t6 ", "t7 ", | ||
|  | 	"s0 ", "s1 ", "s2 ", "s3 ", "s4 ", "s5 ", "s6 ", "a0 ", "a1 ", | ||
|  | 	"a2 ", "a3 ", "a4 ", "a5 ", "t8 ", "t9 ", "t10", "t11", "ra ", | ||
|  | 	"pv ", "at ", "gp ", "sp ", "0" | ||
|  | }; | ||
|  | 
 | ||
|  | 
 | ||
|  | static instr * | ||
|  | display_stored_regs(instr * pro_pc, unsigned char * sp) | ||
|  | { | ||
|  | 	instr * ret_pc = 0; | ||
|  | 	int reg; | ||
|  | 	unsigned long value; | ||
|  | 
 | ||
|  | 	printk("Prologue [<%p>], Frame %p:\n", pro_pc, sp); | ||
|  | 	while (!BB_END(*pro_pc)) | ||
|  | 		if (STK_PUSH_MATCH(*pro_pc)) { | ||
|  | 			reg = (*pro_pc & MEM_REG) >> 21; | ||
|  | 			value = *(unsigned long *)(sp + (*pro_pc & MEM_OFF)); | ||
|  | 			if (reg == 26) | ||
|  | 				ret_pc = (instr *)value; | ||
|  | 			printk("\t\t%s / 0x%016lx\n", reg_name[reg], value); | ||
|  | 		} | ||
|  | 	return ret_pc; | ||
|  | } | ||
|  | 
 | ||
|  | static instr * | ||
|  | seek_prologue(instr * pc) | ||
|  | { | ||
|  | 	while (!STK_ALLOC_MATCH(*pc)) | ||
|  | 		--pc; | ||
|  | 	while (!BB_END(*(pc - 1))) | ||
|  | 		--pc; | ||
|  | 	return pc; | ||
|  | } | ||
|  | 
 | ||
|  | static long | ||
|  | stack_increment(instr * prologue_pc) | ||
|  | { | ||
|  | 	while (!STK_ALLOC_MATCH(*prologue_pc)) | ||
|  | 		++prologue_pc; | ||
|  | 
 | ||
|  | 	/* Count the bytes allocated. */ | ||
|  | 	if ((*prologue_pc & STK_ALLOC_1M) == STK_ALLOC_1M) | ||
|  | 		return -(((long)(*prologue_pc) << 48) >> 48); | ||
|  | 	else | ||
|  | 		return (*prologue_pc >> 13) & 0xff; | ||
|  | } | ||
|  | 
 | ||
|  | void | ||
|  | stacktrace(void) | ||
|  | { | ||
|  | 	instr * ret_pc; | ||
|  | 	instr * prologue = (instr *)stacktrace; | ||
|  | 	register unsigned char * sp __asm__ ("$30"); | ||
|  | 
 | ||
|  | 	printk("\tstack trace:\n"); | ||
|  | 	do { | ||
|  | 		ret_pc = display_stored_regs(prologue, sp); | ||
|  | 		sp += stack_increment(prologue); | ||
|  | 		prologue = seek_prologue(ret_pc); | ||
|  | 	} while (IS_KERNEL_TEXT(ret_pc)); | ||
|  | } |