dma: assertion failure in multiple_partitions example

[dotnwat]

nwatkins@node0:~/src/legion/examples/08_multiple_partitions$ GASNET_BACKTRACE=1 SSH_SERVERS="node0" amudprun -np 1 ./multiple_partitions
Pinned Memory Usage: GASNET=256, RMEM=0, LMB=2, SDP=64, total=322
multiple_partitions: /users/nwatkins/src/legion/runtime/channel.h:1085: void LegionRuntime::LowLevel::XferDesQueue::enqueue_xferDes(LegionRuntime::LowLevel::XferDes*): Assertion `it != channel_to_dma_thread.end()' failed.
Running stencil computation for 1024 elements...
Partitioning data into 4 sub-regions...
Initializing field 0 for block 0...
Initializing field 0 for block 1...
Initializing field 0 for block 2...
Initializing field 0 for block 3...
*** Caught a fatal signal: SIGABRT(6) on node 0/1

[dotnwat]

ping @jiazhihao

[dotnwat]

Same issue for the partitioning example

nwatkins@node0:/mnt/legion/legion/examples/07_partitioning$ GASNET_BACKTRACE=1 SSH_SERVERS="node0 node1 node-2" amudprun -np 3 ./partitioning
Pinned Memory Usage: GASNET=256, RMEM=0, LMB=6, SDP=64, total=326
Running daxpy for 1024 elements...
Partitioning data into 4 sub-regions...
Initializing field 0 for block 0...
Initializing field 0 for block 3...
Initializing field 1 for block 0...
Initializing field 1 for block 3...
Running daxpy computation with alpha 3.907985e-14 for point 0...
Running daxpy computation with alpha 3.907985e-14 for point 3...
partitioning: /users/nwatkins/src/legion/runtime/channel.h:1085: void LegionRuntime::LowLevel::XferDesQueue::enqueue_xferDes(LegionRuntime::LowLevel::XferDes*): Assertion `it != channel_to_dma_thread.end()' failed.

[jiazhihao]

This assertion failure happens because we have enqueued GASNet xfer descriptors, but didn't initialize GASNet channels. I have fixed this problem in a upcoming commit. I am still testing the commit, and will push it in next couple hours.