[openib-general] Re: [PATCH] kDAPL: convert the ep list to linux native

[James Lentini]

On Mon, 13 Jun 2005, Tom Duffy wrote:

> On Mon, 2005-06-13 at 17:10 -0400, James Lentini wrote:
>> This looks good. I've checked it in as revision 2595.
>
> Thanks.
>
>> Eventually, we could move the list up into the dapl_common structure.
>
> Gross.  I agree with Christoph.

You find the dapl_common structure gross from a style point of view, 
right? I agree that some of the fields currently in dapl_common are 
not actually necessary for every DAPL object (e.g. a dapl_ia does not 
need an owner_ia pointer). I see these as implementation errors, but I 
still see value in using a common structure in principal. Is there a 
performance problem that I am missing?

>> The one oddity is that all the objects are put on the IA list except
>> CRs which are placed on an SP. I think it would be worth reflecting
>> this in the list's member name. Instead of calling it a ia_list_entry
>> as it is now, a name like parent_list or owner_list would be more
>> appropriate.
>
> Eventually, wouldn't we get rid of ia_list_entry?  Cause each struct has
> its own list entry (name "list", which seems to be the convention), and
> the IA has the heads of each list.

That would be the other alternative.

Right now, dapl_common has an ia_list_entry member. For each DAPL 
object, this list entry that gets linked on a list head stored in the 
parent IA. There are two exceptions to this rule:

  - a CR's ia_list_entry is linked onto its parent SP's cr list.
  - an IA's ia_list_entry is unused. It has a separate
    hca_ia_list_entry that it links onto its parent HCA's ia list

Obviously this is confusing; when I looked at it yesterday I didn't 
realize that an IA's ia_list_entry was unused.

My suggestion yesterday was to replace dapl_common's ia_list_entry 
member with a list_head (and remove the list_head's in the individual 
dapl object).

The above option is moot if we remove dapl_common all together.

> Your wording is a bit confusing cause you say, "all the objects are put
> on the IA list".  Shouldn't that read, "each of the objects is put on
> its respective list owned by the IA" or some such?

Your right, my wording was poor. You description is correct.

>
> -tduffy
>