static void perf_callchain_kernel(struct pt_regs *regs,
struct perf_callchain_entry *entry)
{
unsigned long sp, next_sp;
unsigned long next_ip;
unsigned long lr;
long level = 0;
unsigned long *fp;
lr = regs->link;
sp = regs->gpr[1];
callchain_store(entry, PERF_CONTEXT_KERNEL);
callchain_store(entry, regs->nip);
if (!validate_sp(sp, current, STACK_FRAME_OVERHEAD))
return;
for (;;) {
fp = (unsigned long *) sp;
next_sp = fp[0];
if (next_sp == sp + STACK_INT_FRAME_SIZE &&
fp[STACK_FRAME_MARKER] == STACK_FRAME_REGS_MARKER) {
/*
* This looks like an interrupt frame for an
* interrupt that occurred in the kernel
*/
regs = (struct pt_regs *)(sp + STACK_FRAME_OVERHEAD);
next_ip = regs->nip;
lr = regs->link;
level = 0;
callchain_store(entry, PERF_CONTEXT_KERNEL);
} else {
if (level == 0)
next_ip = lr;
else
next_ip = fp[STACK_FRAME_LR_SAVE];
/*
* We can't tell which of the first two addresses
* we get are valid, but we can filter out the
* obviously bogus ones here. We replace them
* with 0 rather than removing them entirely so
* that userspace can tell which is which.
*/
if ((level == 1 && next_ip == lr) ||
(level <= 1 && !kernel_text_address(next_ip)))
next_ip = 0;
++level;
}
callchain_store(entry, next_ip);
if (!valid_next_sp(next_sp, sp))
return;
sp = next_sp;
}
}
static void
perf_callchain_kernel(struct pt_regs *regs, struct perf_callchain_entry *entry)
{
callchain_store(entry, PERF_CONTEXT_KERNEL);
callchain_store(entry, regs->pc);
unwind_stack(NULL, regs, NULL, &callchain_ops, entry);
}
static void callchain_address(void *data, unsigned long addr, int reliable)
{
struct perf_callchain_entry *entry = data;
if (reliable)
callchain_store(entry, addr);
}
