Re: try_then_request_module

[Ingo Oeser]

Hi Rusty,
hi LKML,

On Mon, May 19, 2003 at 11:41:20AM +1000, Rusty Russell wrote:
> If someone is feeling eager, many callers could change to
> try_then_request_module(), eg:

[search || request_module]

Many implementation do this with a search and retry the search 
(if clever with a goto and a flag variable to save kernel size)
after module loading.

All that implemented in the search routine, which you have to
supply anyway.

So try_then_request_module() will consolidate the the
branch or in the worst case just duplicating that code
everywhere (depends on wether you implement it as a non-inline
function or define).

Usally this is all as simple as:

   int module_loaded_flag=0;
retry_with_module_loaded:
   
   /* search code */
   
   if (!module_loaded_flag && !found) {
      module_loaded_flag=1;
      if (!request_module(bla))
         goto retry_with_module_loaded;
   }
   return found;

which is very space effecient and also still readable.

Regards

Ingo Oeser