2.4.2-1

Add tree algorithms for allreduce to improve performance at scale.
Add ncclCommAbort() and ncclCommGetAsyncError() to properly handle
network errors and be permit recover.
Detect initial CPU affinity and no longer escape it.

src/misc/group.cu

@@ -179,13 +179,13 @@ group_cleanup:
   // an atomic operation, we need to cancel all operations.
   for (int i=0; i<ncclGroupIndex; i++) {
     struct ncclComm* comm = ncclGroupArgs[i].coll.comm;
-    for (int r=0; r<comm->nRings; r++) {
-      struct ncclRing* ring = comm->rings+r;
-      for (int i=0; i<ring->collCount; i++) {
-        ring->collectives[(ring->collStart + i)%NCCL_MAX_OPS].active = 0;
+    for (int c=0; c<comm->nChannels; c++) {
+      struct ncclChannel* channel = comm->channels+c;
+      for (int i=0; i<channel->collCount; i++) {
+        channel->collectives[(channel->collStart + i)%NCCL_MAX_OPS].active = 0;
       }
-      ring->collFifoTail = ring->collStart;
-      ring->collCount = 0;
+      channel->collFifoTail = channel->collStart;
+      channel->collCount = 0;
     }
     comm->myParams->gridDim.x = comm->myParams->blockDim.x = 0;
     comm->userStreamSet = false;