Merge pull request #210 from wenkaidu/unroll

Revert "Tuning the inline and unroll to reduce the scratch usage"

src/collectives/device/all_reduce.h

@@ -102,7 +102,7 @@ __device__ void ncclAllReduceRingKernel(struct CollectiveArgs* args) {
 #endif
 }
 
-template<int UNUSED, class FUNC, typename T>
+template<int UNROLL, class FUNC, typename T>
 __attribute__((noinline))
 __device__ void ncclAllReduceTreeKernel(struct CollectiveArgs* args) {
   const int tid = threadIdx.x;
@@ -128,7 +128,7 @@ __device__ void ncclAllReduceTreeKernel(struct CollectiveArgs* args) {
     struct ncclTree* tree = &channel->treeUp;
     // Reduce : max number of recv is 3, max number of send is 1 (binary tree + local)
     ncclPrimitivesRecvData<T, NCCL_MAX_TREE_ARITY> recvData;
-    ncclPrimitives<1, 1, 1, T, NCCL_MAX_TREE_ARITY, 1, FUNC> prims(tid, args->nThreads, tree->down, &tree->up, NULL, stepSize, channel, comm, args->opCount, recvData);
+    ncclPrimitives<UNROLL, 1, 1, T, NCCL_MAX_TREE_ARITY, 1, FUNC> prims(tid, args->nThreads, tree->down, &tree->up, NULL, stepSize, channel, comm, args->opCount, recvData);
     for (ssize_t gridOffset = 0; gridOffset < size; gridOffset += loopSize) {
       // Up
       ssize_t offset = gridOffset + bid*chunkSize;
@@ -147,7 +147,7 @@ __device__ void ncclAllReduceTreeKernel(struct CollectiveArgs* args) {
     struct ncclTree* tree = &channel->treeDn;
     // Broadcast : max number of recv is 1, max number of send is 3 (binary tree + local)
     ncclPrimitivesSendData<T, NCCL_MAX_TREE_ARITY> sendData;
-    ncclPrimitives<1, 1, 1, T, 1, NCCL_MAX_TREE_ARITY, FUNC> prims(tid, args->nThreads, &tree->up, tree->down, NULL, stepSize, channel, comm, args->opCount, sendData);
+    ncclPrimitives<UNROLL, 1, 1, T, 1, NCCL_MAX_TREE_ARITY, FUNC> prims(tid, args->nThreads, &tree->up, tree->down, NULL, stepSize, channel, comm, args->opCount, sendData);
     for (ssize_t gridOffset = 0; gridOffset < size; gridOffset += loopSize) {
       // Down
       ssize_t offset = gridOffset + bid*chunkSize;