On Wed, Sep 11, 2013 at 5:08 PM, Mark Cottrell <mark.cottr...@taitradio.com> wrote: > Hi Tom, > > I spent a while playing around with this, including adding a bunch of debug > output to tpb_thread_body::tpb_thread_body, and found that when a block is > done, the DONE state should propagate through the flow graph as > tpb_detail::notify_neighbours is called (as I'm sure you're aware). The > problem is, tpb_detail::notify_neighbours only notifies blocks that that > have input or output buffers (which as far as I can tell, blocks with only > message inputs or outputs don't), so blocks like message_debug will block on > tpb_detail::input_cond forever (on line 110 of tpb_thread_body.cc) and can > never be notified (as it has no input buffers, so notify downstream does > nothing). > > Johnathan contacted me r.e. this and I sent him a patch which fixed the > problem for me (attached to this message), but I don't think he has had time > to look at it yet. The gist of it is that it uses pmt::PMT_EOF to indicate > that message blocks should transition to done and notify neighbours. > > Please feel free to correct me on any of what I said above, this was my > first foray into the scheduler so I could have it completely wrong. > > Thanks, > Mark
Yeah, ok, I see the problem. I think I remember now someone else talking about this potential issue. I'll discuss your patch with Johnathan sometime soon. I see where you're going with it, but I'm hoping that there's a solution that's a bit simpler (or just fewer changes). Thanks, -- Tom Visit us at GRCon13 Oct. 1 - 4 http://www.trondeau.com/grcon13 > On Thu, Sep 12, 2013 at 3:56 AM, Tom Rondeau <t...@trondeau.com> wrote: >> >> On Thu, Aug 22, 2013 at 10:44 PM, Mark Cottrell >> <mark.cottr...@taitradio.com> wrote: >> > Hello all, >> > >> > I have written a sync block that takes in samples and outputs messages >> > (similar to tagged_stream_to_pdu), but when writing a test for the block >> > I >> > found that when I called top_block.run(), the test never finished, as it >> > appears to be hanging on the call to top_block.wait(). >> > >> > The flow graph for the test is as follows: >> > non-repeating file source -> my block -> message_debug >> > >> > is hanging the expected behaviour? I can work around it by counting the >> > number of items written by the file source, but it would be nice to have >> > it >> > terminate of its own accord. >> > >> > Thanks, >> > Mark >> >> >> Mark, >> >> No, that's not expected behavior. When the file sink finishes, it >> should set the DONE stage in the scheduler that should indicated to >> every down stream block that they are also done. >> >> Make sure that there isn't something happening where your block isn't >> getting stuck in 'work' at this point. >> >> -- >> Tom >> Visit us at GRCon13 Oct. 1 - 4 >> http://www.trondeau.com/grcon13 _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
