2.21.5-1

Add support for IB SHARP 1PPN operation with user buffers.
Improve support for MNNVL, add NVLS support and multi-clique support.
 * Detect the NVLS clique through NVML
 * Exchange XML between peers in the same NVLS clique and fuse XMLs
   before creating the topology graph.
 * Rework bootstrap allgather algorithms to allow for large allgather
   operations intra-node (XML exchange).
Net/IB: add support for dynamic GID detection.
 * Automatically select RoCEv2/IPv4 interface by default. Allow to
   select IPv6 or even the network/mask.
Reduce NVLS memory usage.
 * Add stepSize as property of a connection to allow for different
   sizes on different peers; set it to 128K for NVLink SHARP.
Improve tuner loading
 * Look for more paths, be more consistent with the network device
   plugin.
 * Also search for tuner support inside the net plugin.
Improve tuner API
 * Add context to support multi-device per process.
Add magic number around comm object to detect comm corruption.
 * Add some basic check around communicators so that we can report a
   problem when a communicator gets corrupted or a wrong comm pointer
   is passed to NCCL.
Fix net/IB error path. Github PR #1164
Fix collnet rail mapping with split comm.
Fix packet reordering issue causing bootstrap mismatch
 * Use a different tag in ncclTransportP2pSetup for the connectInfo
   exchange and the following barrier.
Fix hang when crossNic is inconsistent between ranks.
Fix minCompCap/maxCompCap computation. Github issue #1184

src/misc/argcheck.cc

@@ -33,6 +33,15 @@ ncclResult_t PtrCheck(void* ptr, const char* opname, const char* ptrname) {
   return ncclSuccess;
 }
 
+ncclResult_t CommCheck(struct ncclComm* comm, const char* opname, const char* ptrname) {
+  NCCLCHECK(PtrCheck(comm, opname, ptrname));
+  if (comm->startMagic != NCCL_MAGIC || comm->endMagic != NCCL_MAGIC) {
+    WARN("Error: corrupted comm object detected");
+    return ncclInvalidArgument;
+  }
+  return ncclSuccess;
+}
+
 ncclResult_t ArgsCheck(struct ncclInfo* info) {
   // First, the easy ones
   if (info->root < 0 || info->root >= info->comm->nRanks) {