Re: [PATCH] xtensa: improve stack dumping

From: Max Filippov
Date: Wed Nov 06 2019 - 19:22:05 EST


On Wed, Nov 6, 2019 at 2:34 PM Joe Perches <joe@xxxxxxxxxxx> wrote:
> > @@ -512,10 +510,12 @@ void show_stack(struct task_struct *task, unsigned long *sp)
> > for (i = 0; i < kstack_depth_to_print; i++) {
> > if (kstack_end(sp))
> > break;
> > - pr_cont(" %08lx", *sp++);
> > + sprintf(buf + (i % 8) * 9, " %08lx", *sp++);
> > if (i % 8 == 7)
> > - pr_cont("\n");
> > + pr_info("%s\n", buf);
> > }
> > + if (i % 8)
> > + pr_info("%s\n", buf);
>
> Could this be done using hex_dump_to_buffer
> by precalculating kstack_end ?

I've got this, but it doesn't look very attractive to me:

void show_stack(struct task_struct *task, unsigned long *sp)
{
unsigned long *stack;
int len;

if (!sp)
sp = stack_pointer(task);
stack = sp;

len = min((-(unsigned long)stack) & (THREAD_SIZE - 4),
kstack_depth_to_print * 4ul);

pr_info("Stack:\n");

for (; len > 0; len -= 32) {
char buf[9 * 8 + 1];

hex_dump_to_buffer(sp, min(len, 32), 32, 4,
buf, sizeof(buf), false);
pr_info(" %08lx: %s\n", (unsigned long)sp, buf);
sp += 8;
}
show_trace(task, stack);
}

--
Thanks.
-- Max