[Pvfs2-developers] a little help?

[Walter B. Ligon III]

Where is this usually done for isys calls that do not complete immediately?

Maybe that doesn't matter, if all we need is what you have below, except 
the part where you put the "XX".  Surely this isn't the return value of 
the isys call, since that is most likely not what you want (and in fact 
will always be SM_ACTION_TERMINATE in this case).

Walt

Murali Vilayannur wrote:
> hi Walt,
> Sorry for not explaining clearly. After the PVFS_isys_*() call completes
> immediately, we need to copy the results from the system
> responses to the kernel by writing it to the device file.
> The ->was_handled_inline member variable is actually set in
> write_inlined_device_response() which also does the kernel copy internally.
> So what I meant to say was..
> 
> Uh, what?  what do you mean by "copy the results to the downcall"?
> 
>> Your post indicated that if the was_handled_inline member was set that
>> was all that was needed.  Is something else needed?  I don't know what a
>> downcall is or how to copy results there.
> 
> 
> 
> switch(ret) {
> case SM_ACTION_TERMINATE:
>    vfs_request->out_downcall.type = vfs_request->in_upcall.type;
>    vfs_request->out_downcall.status = XX; /* This should be set to the
> return value of the isys_* call */
>    write_inlined_device_response(vfs_request);
>   /* Fall through */
> case 0:
>    if (vfs_request->was_handled_inline) {
>       ret = repost_unexp_vfs_request(vfs_request, "..");
>    }
> ....
> 
> perhaps that explained it a little better I hope,
> thanks,
> Murali
> 
> Walt
> 
>>
>> Murali Vilayannur wrote:
>> > Hi Walt,
>> >
>> >> Maybe it would be simpler to modify the code as shown:
>> >>
>> >> >>     /*
>> >> >>       check if we need to repost the operation (in case of failure
>> or
>> >> >>       inlined handling/completion)
>> >> >>     */
>> >> >>     switch(ret)
>> >> >>     {
>> >>             case SM_ACTION_TERMINATE:
>> >>                 vfs->request->was_handled_inline = 1;
>> >
>> >
>> >
>> >
>> > Ok, that works too :)
>> > Just remember to copy the results to the downcall (calling the
>> > write_inlined_device_response should do the trick)
>> > before reposting the op.
>> > thanks,
>> > Murali
>> >
>> >>                 /* this code falls through to the next case */
>> >> >>         case 0:
>> >> >>         {
>> >> >>             /*
>> >> >>               if we've already completed the operation, just repost
>> >> >>               the unexp request
>> >> >>             */
>> >> >>             if (vfs_request->was_handled_inline)
>> >> >>             {
>> >> >>                 ret = repost_unexp_vfs_request(
>> >> >>                     vfs_request, "inlined completion");
>> >> >>             }
>> >> >>             else
>> >> >>             {
>> >> >
>> >> >
>> >> > What we could do to retain this part of the code is to set the
>> >> > ->was_handled_inline member variable in all the post_*_request()
>> >> functions
>> >> > if the PVFS_isys_*() function indicated that the posted operation
>> >> finished
>> >> > immediately.
>> >> > If we do that, then we could retain this code as is without adding
>> any
>> >> > more cases. Great catch!
>> >> > thanks,
>> >> > Murali
>> >> >
>> >> >
>> >> >>                 /*
>> >> >>                   otherwise, we've just properly posted a
>> non-blocking
>> >> >>                   op; mark it as no longer a dev unexp msg and add
>> it
>> >> >>                   to the ops in progress table
>> >> >>                 */
>> >> >>                 vfs_request->is_dev_unexp = 0;
>> >> >>                 ret = add_op_to_op_in_progress_table(vfs_request);
>> >> >>#if 0
>> >> >>                 assert(is_op_in_progress(vfs_request));
>> >> >>#endif
>> >> >>             }
>> >> >>         }
>> >> >>         break;
>> >> >>         case REMOUNT_PENDING:
>> >> >>             ret = repost_unexp_vfs_request(
>> >> >>                 vfs_request, "mount pending");
>> >> >>             break;
>> >> >>         case OP_IN_PROGRESS:
>> >> >>             ret = repost_unexp_vfs_request(
>> >> >>                 vfs_request, "op already in progress");
>> >> >>             break;
>> >> >>         default:
>> >> >>             PVFS_perror_gossip("Operation failed", ret);
>> >> >>             ret = repost_unexp_vfs_request(
>> >> >>                 vfs_request, "failure");
>> >> >>             break;
>> >> >>     }
>> >> >>     return ret;
>> >> >>}
>>
>> -- 
>> Dr. Walter B. Ligon III
>> Associate Professor
>> ECE Department
>> Clemson University
>>
> 

-- 
Dr. Walter B. Ligon III
Associate Professor
ECE Department
Clemson University