Re: ocstat

["Simon 'corecode' Schubert" <corecode@xxxxxxxxxxxx>]

Aggelos Economopoulos wrote:
> Should be useful. A thing that afaict is lacking from objectcache at the
> moment is a debug mode; I've spend 1+ day chasing a bug that was caused by
> a very subtle double free for an mbuf and the way I did it (add kprintf()s
> for every mbuf malloc/free, also logging their call sites and write script
> to track alloc/frees) cannot be reused. If kmalloc/kfree can detect stuff
> like that we could add an option that makes objcache pass through all gets
> and puts. Ideas?

We could enable invariant functions on the objcache, i.e. checking for 
conformity on put and get (detects tampering while free and with a flag, 
detects double free).  In itself it would be quite hard to detect a double 
free, as we are storing typed objects and thus we can't change anything in 
the object to signal "has been freed".

cheers
  simon

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