The following scenario might occur when nvmf_tgt is stopped:
1. nvmf_tgt receives SIGINT, changes state to NVMF_TGT_FINI_STOP_SUBSYSTEMS
2. In this state nvmf_tgt stops all subsystems and disconnects associated qpairs
3. In the case of RDMA qpair, its state will be changed to IBV_QPS_ERR.
Once qpair changes the state to IBV_QPS_ERR, RDMA device generates
LAST_WQE_REACHED event when there are no more WQE that can be sonsumed
from the SRQ by this qpair.
4. When all subsystems are stopped, some of qpair may still be alive since they
haven't received LAST_WQE_REACHED event yet.
5. nvmf_tgt stops all poll groups and forcefully destroyes any qpairs linked to them.
6. At this moment LAST_WQE_REACHED event might be generated and received in another thread.
Handler of this event sends a message with a pointer to qpair. The qpair itself may already
be destroyed.
7. Thread that owned qpair receives a message (LAST_WQE_REACHED) with a pointer to alredy destroyed qpair and
destroyes it for the second time when all pointer are invalid.
ibv events related to qpair should be handled by the thread that
owns this qpair. This commit adds a new structure that describes
ibv event, helper functions for sending the event and a list
of events per rdma qpair; add syncronization for LAST_WQE_REACHED event
Fixes#1075
Signed-off-by: Alexey Marchuk <alexeymar@mellanox.com>
Signed-off-by: Sasha Kotchubievsky <sashakot@mellanox.com>
Signed-off-by: Evgeniy Kochetov <evgeniik@mellanox.com>
Change-Id: I22bff89741708df2518760934ecb4e33fad49473
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/476712
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Broadcom SPDK FC-NVMe CI <spdk-ci.pdl@broadcom.com>
Community-CI: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Seth Howell <seth.howell@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
dc84fbaaa1