send NS_POUT_UNBLOCK_ACK before signalling S_NS_UNBLOCK

In gprs_ns_process_msg(), we were dispatching the S_NS_UNBLOCK
signal before sending out the NS_POUT_UNBLOCK_ACK message.

Signal handlers might send messages to the other side, assuming
that NS is now unblocked. However, since such messages will arrive
before the UNBLOCK_ACK message the receiver might discard them.
This problem has been observed with our TTCN3 BSSGP_Emulation
as a peer to osmo-pcu.

This patch makes TTCN3 PCU TC_paging() test pass regardless of
whether the test or osmo-pcu is started first. Before this patch,
this test would only pass if the test was started before osmo-pcu.
A remaining problem is that the test does not yet keep passing
reliably unless osmo-pcu is restarted between test runs.

Change-Id: I3af54a14bb6bcfa167c9a9d9f67835e7f5b9f1bb
Related: OS#2890
Related: OS#2388

0 files changed, 0 insertions, 0 deletions