Re: [Lksctp-developers] Re: Just Dispositions

[La M. H.P. Y. <pi...@em...>]

Comments below inline.

Jon Grimm writes:
 > 
 > La Monte Henry Piggy Yarroll wrote:
 > 
 > > Jon Grimm <jg...@au...> writes:
 > > 
 > >>La Monte H.P. Yarroll wrote:
 > >>
 > >>>Yeah, new state.  The EMPTY state is there for an association cache.
 > >>>If we decide that kalloc()ing them all the time is too expensive, we
 > >>>can keep a few around pre-allocated.
 > >>>
 > > 
 > > I might add that EMPTY has the value 0 so that it gets set
 > > automagically with the appropriate memset().
 > > 
 > > 
 > >>Hi La Monte,
 > >>
 > >>The fixed size object cache is a good idea and we could create our own 
 > >>slab cache around for association structs.   How did you think of 
 > >>hooking this in?
 > >>
 > > 
 > > It is just a matter of altering association_new() and association_free(),
 > > no?  I can't claim credit for this, as I stole it from Randy, but the
 > > Linux kernel is full of similar examples.  I would point out that this
 > > is an optimization issue and thus not of immediate interest.
 >
 > I think my question was _much_ too ambiguous.  I know where we would 
 > hook it in for allocation, I'm trying to figure the correlation to the 
 > STATE_EMPTY and why you need the STATE_EMPTY to do this?   I think I'm 
 > missing the big picture on how you expected to use this.

Oh, sorry.  SCTP_STATE_EMPTY is for unused association objects which
are in the cache.  Mostly it is a bug catcher.  You COULD implement
the cache by creating a simple array of association structures, in
which case you need to be able to mark available cache entries.

Now that I think about it, association_free() should mark the
association as SCTP_STATE_EMPTY before calling kfree().  This should
catch cases of premature frees.

 > Its no big deal, as its not an immediate concern, but when you get the 
 > chance clue me in on this.
 > 
 > Thanks,
 > jon
 > 
 > 
 > > 
 > >>Color me intrigued,
 > >>Jon