void unwind_stack(void) {
struct sigcontext sc;
jmp_buf env;
/* get current context */
if (0 != setjmp(env)) {
perror("setjmp() failed");
exit(-1);
}
/* set up (partial) sigcontext */
sc.ebp = (unsigned long)env->__jmpbuf[EBP];
sc.esp = (unsigned long)env->__jmpbuf[ESP];
sc.eip = (unsigned long)env->__jmpbuf[EIP];
/* jump current frame */
unwind_frame(&sc);
/* stack back trace */
while (sc.eip != 0) {
fprintf(stdout,
"pc=0x%lx sp=0x%lx bp=0x%lx\n", sc.eip, sc.esp, sc.ebp);
unwind_frame(&sc);
}
}
static struct pt_regs * unwind_get_regs(struct task_struct *tsk)
{
struct stackframe frame;
register unsigned long current_sp asm ("sp");
int found = 0;
//unsigned long sc;
if (!tsk)
tsk = current;
printk("tsk = %p,comm=%s,pid=%d,pgd=0x%p\n", tsk , tsk->comm , tsk->pid , tsk->mm->pgd );
if (tsk == current) {
frame.fp = (unsigned long)__builtin_frame_address(0);
frame.sp = current_sp;
frame.lr = (unsigned long)__builtin_return_address(0);
frame.pc = (unsigned long)unwind_get_regs;
} else {
/* task blocked in __switch_to */
frame.fp = thread_saved_fp(tsk);
frame.sp = thread_saved_sp(tsk);
/*
* The function calling __switch_to cannot be a leaf function
* so LR is recovered from the stack.
*/
frame.lr = 0;
frame.pc = thread_saved_pc(tsk);
}
while (1) {
int urc;
//unsigned long where = frame.pc;
urc = unwind_frame(&frame);
if (urc < 0)
break;
//dump_backtrace_entry(where, frame.pc, frame.sp - 4);
if( frame.pc == (unsigned long)ret_fast_syscall ){
found = 1;
break;
}
}
if( !found )
return NULL;
#if 0
//printk("FRAME:sp=0x%lx,pc=0x%lx,lr=0x%lx,fp=0x%lx\n" , frame.sp,frame.pc,frame.lr,frame.fp );
//rk28_printk_mem((unsigned int*)(frame.sp-sizeof(struct pt_regs)),2*sizeof(struct pt_regs)/4+8, NULL );
sc =*( (unsigned long*)(frame.sp-4));
if( sc >= (unsigned long)&_text && sc < (unsigned long)&_end ){
print_symbol("sys call=%s\n",sc );
}
#endif
return (struct pt_regs *)(frame.sp+8); // 8 for reg r4,r5 as fifth and sixth args.
}
void notrace walk_stackframe(struct stackframe *frame,
int (*fn)(struct stackframe *, void *), void *data)
{
while (1) {
int ret;
if (fn(frame, data))
break;
ret = unwind_frame(frame);
if (ret < 0)
break;
}
}
void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
{
struct stackframe frame;
int skip;
pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
if (!tsk)
tsk = current;
if (!try_get_task_stack(tsk))
return;
if (tsk == current) {
frame.fp = (unsigned long)__builtin_frame_address(0);
frame.pc = (unsigned long)dump_backtrace;
} else {
/*
* task blocked in __switch_to
*/
frame.fp = thread_saved_fp(tsk);
frame.pc = thread_saved_pc(tsk);
}
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
frame.graph = 0;
#endif
skip = !!regs;
printk("Call trace:\n");
do {
/* skip until specified stack frame */
if (!skip) {
dump_backtrace_entry(frame.pc);
} else if (frame.fp == regs->regs[29]) {
skip = 0;
/*
* Mostly, this is the case where this function is
* called in panic/abort. As exception handler's
* stack frame does not contain the corresponding pc
* at which an exception has taken place, use regs->pc
* instead.
*/
dump_backtrace_entry(regs->pc);
}
} while (!unwind_frame(tsk, &frame));
put_task_stack(tsk);
}
unsigned long profile_pc(struct pt_regs *regs)
{
struct stackframe frame;
if (!in_lock_functions(regs->ARM_pc))
return regs->ARM_pc;
arm_get_current_stackframe(regs, &frame);
do {
int ret = unwind_frame(&frame);
if (ret < 0)
return 0;
} while (in_lock_functions(frame.pc));
return frame.pc;
}
void notrace walk_stackframe(struct stackframe *frame,
int (*fn)(struct stackframe *, void *), void *data)
{
while (1) {
int ret;
if (fn(frame, data))
break;
#if defined(CONFIG_ARM_UNWIND)
ret = unwind_frame(frame);
#else
ret = -1;
#endif
if (ret < 0)
break;
}
}
unsigned long profile_pc(struct pt_regs *regs)
{
struct stackframe frame;
if (!in_lock_functions(regs->pc))
return regs->pc;
frame.fp = regs->regs[29];
frame.sp = regs->sp;
frame.pc = regs->pc;
do {
int ret = unwind_frame(&frame);
if (ret < 0)
return 0;
} while (in_lock_functions(frame.pc));
return frame.pc;
}
void aee_dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
{
struct stackframe frame;
const register unsigned long current_sp asm("sp");
pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
if (!tsk)
tsk = current;
if (regs) {
frame.fp = regs->regs[29];
frame.sp = regs->sp;
frame.pc = regs->pc;
} else if (tsk == current) {
frame.fp = (unsigned long)__builtin_frame_address(0);
frame.sp = current_sp;
frame.pc = (unsigned long)aee_dump_backtrace;
} else {
/*
* task blocked in __switch_to
*/
frame.fp = thread_saved_fp(tsk);
frame.sp = thread_saved_sp(tsk);
frame.pc = thread_saved_pc(tsk);
}
aee_sram_fiq_log("Call trace:\n");
while (1) {
unsigned long where = frame.pc;
int ret;
ret = unwind_frame(&frame);
if (ret < 0)
break;
dump_backtrace_entry(where, frame.sp);
}
}
void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
{
struct stackframe frame;
unsigned long irq_stack_ptr;
int skip;
pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
if (!tsk)
tsk = current;
if (!try_get_task_stack(tsk))
return;
/*
* Switching between stacks is valid when tracing current and in
* non-preemptible context.
*/
if (tsk == current && !preemptible())
irq_stack_ptr = IRQ_STACK_PTR(smp_processor_id());
else
irq_stack_ptr = 0;
if (tsk == current) {
frame.fp = (unsigned long)__builtin_frame_address(0);
frame.sp = current_stack_pointer;
frame.pc = (unsigned long)dump_backtrace;
} else {
/*
* task blocked in __switch_to
*/
frame.fp = thread_saved_fp(tsk);
frame.sp = thread_saved_sp(tsk);
frame.pc = thread_saved_pc(tsk);
}
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
frame.graph = tsk->curr_ret_stack;
#endif
skip = !!regs;
printk("Call trace:\n");
while (1) {
unsigned long where = frame.pc;
unsigned long stack;
int ret;
/* skip until specified stack frame */
if (!skip) {
dump_backtrace_entry(where);
} else if (frame.fp == regs->regs[29]) {
skip = 0;
/*
* Mostly, this is the case where this function is
* called in panic/abort. As exception handler's
* stack frame does not contain the corresponding pc
* at which an exception has taken place, use regs->pc
* instead.
*/
dump_backtrace_entry(regs->pc);
}
ret = unwind_frame(tsk, &frame);
if (ret < 0)
break;
stack = frame.sp;
if (in_exception_text(where)) {
/*
* If we switched to the irq_stack before calling this
* exception handler, then the pt_regs will be on the
* task stack. The easiest way to tell is if the large
* pt_regs would overlap with the end of the irq_stack.
*/
if (stack < irq_stack_ptr &&
(stack + sizeof(struct pt_regs)) > irq_stack_ptr)
stack = IRQ_STACK_TO_TASK_STACK(irq_stack_ptr);
dump_mem("", "Exception stack", stack,
stack + sizeof(struct pt_regs));
}
}
put_task_stack(tsk);
}
bool JavaThread::pd_get_top_frame(frame* fr_addr,
void* ucontext, bool isInJava, bool makeWalkable) {
assert(this->is_Java_thread(), "must be JavaThread");
JavaThread* jt = (JavaThread *)this;
if (!isInJava && makeWalkable) {
// make_walkable flushes register windows and grabs last_Java_pc
// which can not be done if the ucontext sp matches last_Java_sp
// stack walking utilities assume last_Java_pc set if marked flushed
jt->frame_anchor()->make_walkable(jt);
}
// If we have a walkable last_Java_frame, then we should use it
// even if isInJava == true. It should be more reliable than
// ucontext info.
if (jt->has_last_Java_frame() && jt->frame_anchor()->walkable()) {
*fr_addr = jt->pd_last_frame();
return true;
}
ucontext_t* uc = (ucontext_t*) ucontext;
// At this point, we don't have a walkable last_Java_frame, so
// we try to glean some information out of the ucontext.
intptr_t* ret_sp;
ExtendedPC addr = os::Solaris::fetch_frame_from_ucontext(this, uc,
&ret_sp, NULL /* ret_fp only used on Solaris X86 */);
if (addr.pc() == NULL || ret_sp == NULL) {
// ucontext wasn't useful
return false;
}
#if INCLUDE_CDS
if (UseSharedSpaces && MetaspaceShared::is_in_shared_region(addr.pc(), MetaspaceShared::md)) {
// In the middle of a trampoline call. Bail out for safety.
// This happens rarely so shouldn't affect profiling.
return false;
}
#endif
frame ret_frame(ret_sp, frame::unpatchable, addr.pc());
// we were running Java code when SIGPROF came in
if (isInJava) {
// If the frame we got is safe then it is most certainly valid
if (ret_frame.safe_for_sender(jt)) {
*fr_addr = ret_frame;
return true;
}
// If it isn't safe then we can try several things to try and get
// a good starting point.
//
// On sparc the frames are almost certainly walkable in the sense
// of sp/fp linkages. However because of recycling of windows if
// a piece of code does multiple save's where the initial save creates
// a real frame with a return pc and the succeeding save's are used to
// simply get free registers and have no real pc then the pc linkage on these
// "inner" temporary frames will be bogus.
// Since there is in general only a nesting level like
// this one deep in general we'll try and unwind such an "inner" frame
// here ourselves and see if it makes sense
frame unwind_frame(ret_frame.fp(), frame::unpatchable, addr.pc());
if (unwind_frame.safe_for_sender(jt)) {
*fr_addr = unwind_frame;
return true;
}
// Well that didn't work. Most likely we're toast on this tick
// The previous code would try this. I think it is dubious in light
// of changes to safe_for_sender and the unwind trick above but
// if it gets us a safe frame who wants to argue.
// If we have a last_Java_sp, then the SIGPROF signal caught us
// right when we were transitioning from _thread_in_Java to a new
// JavaThreadState. We use last_Java_sp instead of the sp from
// the ucontext since it should be more reliable.
if (jt->has_last_Java_frame()) {
ret_sp = jt->last_Java_sp();
frame ret_frame2(ret_sp, frame::unpatchable, addr.pc());
if (ret_frame2.safe_for_sender(jt)) {
*fr_addr = ret_frame2;
return true;
}
}
// This is the best we can do. We will only be able to decode the top frame
*fr_addr = ret_frame;
return true;
}
// At this point, we know we weren't running Java code. We might
// have a last_Java_sp, but we don't have a walkable frame.
// However, we might still be able to construct something useful
// if the thread was running native code.
if (jt->has_last_Java_frame()) {
assert(!jt->frame_anchor()->walkable(), "case covered above");
frame ret_frame(jt->last_Java_sp(), frame::unpatchable, addr.pc());
*fr_addr = ret_frame;
return true;
}
// nothing else to try but what we found initially
*fr_addr = ret_frame;
return true;
}
