Merge pull request open-mpi#12241 from edgargabriel/pr/accelerator-size-0-fix-v5.0.x

opal/accelerator: allow 0 size copies - v5.0.x

Author: janjust

opal/mca/accelerator/cuda/accelerator_cuda.c

@@ -364,9 +364,12 @@ static int accelerator_cuda_memcpy_async(int dest_dev_id, int src_dev_id, void *
         return delayed_init;
     }
 
-    if (NULL == stream || NULL == dest || NULL == src || size <= 0) {
+    if (NULL == stream || NULL == dest || NULL == src || size < 0) {
         return OPAL_ERR_BAD_PARAM;
     }
+    if (0 == size) {
+        return OPAL_SUCCESS;
+    }
 
     result = cuMemcpyAsync((CUdeviceptr) dest, (CUdeviceptr) src, size, *(CUstream *)stream->stream);
     if (OPAL_UNLIKELY(CUDA_SUCCESS != result)) {
@@ -387,9 +390,12 @@ static int accelerator_cuda_memcpy(int dest_dev_id, int src_dev_id, void *dest,
         return delayed_init;
     }
 
-    if (NULL == dest || NULL == src || size <= 0) {
+    if (NULL == dest || NULL == src || size < 0) {
         return OPAL_ERR_BAD_PARAM;
     }
+    if (0 == size) {
+        return OPAL_SUCCESS;
+    }
 
     /* Async copy then synchronize is the default behavior as some applications
      * cannot utilize synchronous copies. In addition, host memory does not need

opal/mca/accelerator/rocm/accelerator_rocm_module.c

@@ -254,9 +254,12 @@ static int mca_accelerator_rocm_memcpy_async(int dest_dev_id, int src_dev_id, vo
                                              opal_accelerator_transfer_type_t type)
 {
     if (NULL == stream || NULL == src ||
-        NULL == dest   || size <= 0) {
+        NULL == dest   || size < 0) {
         return OPAL_ERR_BAD_PARAM;
     }
+    if (0 == size) {
+        return OPAL_SUCCESS;
+    }
 
     hipError_t err = hipMemcpyAsync(dest, src, size, hipMemcpyDefault,
                                               *((hipStream_t *)stream->stream));
@@ -275,9 +278,12 @@ static int mca_accelerator_rocm_memcpy(int dest_dev_id, int src_dev_id, void *de
 {
     hipError_t err;
 
-    if (NULL == src || NULL == dest || size <=0) {
+    if (NULL == src || NULL == dest || size < 0) {
         return OPAL_ERR_BAD_PARAM;
     }
+    if (0 == size) {
+        return OPAL_SUCCESS;
+    }
 
     if (type == MCA_ACCELERATOR_TRANSFER_DTOH && size <= opal_accelerator_rocm_memcpyD2H_limit) {
         memcpy(dest, src, size);