Re: 4KSTACKS + DEBUG_STACKOVERFLOW harmful

Denys Vlasenko
2007-08-31T11:12:06Z

On Wednesday 29 August 2007 23:34, Eric Sandeen wrote:
> Noticed today that the combination of 4KSTACKS and DEBUG_STACKOVERFLOW
> config options is a bit deadly.
>
> DEBUG_STACKOVERFLOW warns in do_IRQ if we're within THREAD_SIZE/8 of the
> end of useable stack space, or 512 bytes on a 4k stack.
...
> The large stack usage in those 2 functions is due to big char arrays, of
> size KSYM_NAME_LEN (128 bytes) and KSYM_SYMBOL_LEN (223 bytes).
>
> IOW, the stack warning effectively reduces useful stack left in our itty
> bitty 4k stacks by over 10%.

KSYM_NAME_LEN = 128 sounds stupid. The name which is wider than 80 chars??
Kernel shouldn't have names that long.
Say, 50 chars ought to be enough.
--
vda