|  | /* | 
|  | * Copyright (C) 2000 Anton Blanchard (anton@linuxcare.com) | 
|  | * | 
|  | * This file implements mcount(), which is used to collect profiling data. | 
|  | * This can also be tweaked for kernel stack overflow detection. | 
|  | */ | 
|  |  | 
|  | #include <linux/linkage.h> | 
|  |  | 
|  | #include <asm/ptrace.h> | 
|  | #include <asm/thread_info.h> | 
|  |  | 
|  | /* | 
|  | * This is the main variant and is called by C code.  GCC's -pg option | 
|  | * automatically instruments every C function with a call to this. | 
|  | */ | 
|  |  | 
|  | #ifdef CONFIG_STACK_DEBUG | 
|  |  | 
|  | #define OVSTACKSIZE	4096		/* lets hope this is enough */ | 
|  |  | 
|  | .data | 
|  | .align		8 | 
|  | panicstring: | 
|  | .asciz		"Stack overflow\n" | 
|  | .align		8 | 
|  | ovstack: | 
|  | .skip		OVSTACKSIZE | 
|  | #endif | 
|  | .text | 
|  | .align		32 | 
|  | .globl		_mcount | 
|  | .type		_mcount,#function | 
|  | .globl		mcount | 
|  | .type		mcount,#function | 
|  | _mcount: | 
|  | mcount: | 
|  | #ifdef CONFIG_STACK_DEBUG | 
|  | /* | 
|  | * Check whether %sp is dangerously low. | 
|  | */ | 
|  | ldub		[%g6 + TI_FPDEPTH], %g1 | 
|  | srl		%g1, 1, %g3 | 
|  | add		%g3, 1, %g3 | 
|  | sllx		%g3, 8, %g3			! each fpregs frame is 256b | 
|  | add		%g3, 192, %g3 | 
|  | add		%g6, %g3, %g3			! where does task_struct+frame end? | 
|  | sub		%g3, STACK_BIAS, %g3 | 
|  | cmp		%sp, %g3 | 
|  | bg,pt		%xcc, 1f | 
|  | nop | 
|  | lduh		[%g6 + TI_CPU], %g1 | 
|  | sethi		%hi(hardirq_stack), %g3 | 
|  | or		%g3, %lo(hardirq_stack), %g3 | 
|  | sllx		%g1, 3, %g1 | 
|  | ldx		[%g3 + %g1], %g7 | 
|  | sub		%g7, STACK_BIAS, %g7 | 
|  | cmp		%sp, %g7 | 
|  | bleu,pt		%xcc, 2f | 
|  | sethi		%hi(THREAD_SIZE), %g3 | 
|  | add		%g7, %g3, %g7 | 
|  | cmp		%sp, %g7 | 
|  | blu,pn		%xcc, 1f | 
|  | 2:	 sethi		%hi(softirq_stack), %g3 | 
|  | or		%g3, %lo(softirq_stack), %g3 | 
|  | ldx		[%g3 + %g1], %g7 | 
|  | cmp		%sp, %g7 | 
|  | bleu,pt		%xcc, 2f | 
|  | sethi		%hi(THREAD_SIZE), %g3 | 
|  | add		%g7, %g3, %g7 | 
|  | cmp		%sp, %g7 | 
|  | blu,pn		%xcc, 1f | 
|  | nop | 
|  | /* If we are already on ovstack, don't hop onto it | 
|  | * again, we are already trying to output the stack overflow | 
|  | * message. | 
|  | */ | 
|  | sethi		%hi(ovstack), %g7		! cant move to panic stack fast enough | 
|  | or		%g7, %lo(ovstack), %g7 | 
|  | add		%g7, OVSTACKSIZE, %g3 | 
|  | sub		%g3, STACK_BIAS + 192, %g3 | 
|  | sub		%g7, STACK_BIAS, %g7 | 
|  | cmp		%sp, %g7 | 
|  | blu,pn		%xcc, 2f | 
|  | cmp		%sp, %g3 | 
|  | bleu,pn		%xcc, 1f | 
|  | nop | 
|  | 2:	mov		%g3, %sp | 
|  | sethi		%hi(panicstring), %g3 | 
|  | call		prom_printf | 
|  | or		%g3, %lo(panicstring), %o0 | 
|  | call		prom_halt | 
|  | nop | 
|  | 1: | 
|  | #endif | 
|  | #ifdef CONFIG_FUNCTION_TRACER | 
|  | #ifdef CONFIG_DYNAMIC_FTRACE | 
|  | mov		%o7, %o0 | 
|  | .globl		mcount_call | 
|  | mcount_call: | 
|  | call		ftrace_stub | 
|  | mov		%o0, %o7 | 
|  | #else | 
|  | sethi		%hi(ftrace_trace_function), %g1 | 
|  | sethi		%hi(ftrace_stub), %g2 | 
|  | ldx		[%g1 + %lo(ftrace_trace_function)], %g1 | 
|  | or		%g2, %lo(ftrace_stub), %g2 | 
|  | cmp		%g1, %g2 | 
|  | be,pn		%icc, 1f | 
|  | mov		%i7, %o1 | 
|  | jmpl		%g1, %g0 | 
|  | mov		%o7, %o0 | 
|  | /* not reached */ | 
|  | 1: | 
|  | #endif | 
|  | #endif | 
|  | retl | 
|  | nop | 
|  | .size		_mcount,.-_mcount | 
|  | .size		mcount,.-mcount | 
|  |  | 
|  | #ifdef CONFIG_FUNCTION_TRACER | 
|  | .globl		ftrace_stub | 
|  | .type		ftrace_stub,#function | 
|  | ftrace_stub: | 
|  | retl | 
|  | nop | 
|  | .size		ftrace_stub,.-ftrace_stub | 
|  | #ifdef CONFIG_DYNAMIC_FTRACE | 
|  | .globl		ftrace_caller | 
|  | .type		ftrace_caller,#function | 
|  | ftrace_caller: | 
|  | mov		%i7, %o1 | 
|  | mov		%o7, %o0 | 
|  | .globl		ftrace_call | 
|  | ftrace_call: | 
|  | call		ftrace_stub | 
|  | mov		%o0, %o7 | 
|  | retl | 
|  | nop | 
|  | .size		ftrace_caller,.-ftrace_caller | 
|  | #endif | 
|  | #endif |