Add MG support to the C API

ci/gpu/build.sh

@@ -62,8 +62,13 @@ conda activate rapids
 export PATH=$(conda info --base)/envs/rapids/bin:$PATH
 
 gpuci_logger "Install dependencies"
+# Assume libcudf will be installed via cudf. This is done to prevent the
+# following:
+# libcudf = 22.04.00a220315, cudf = 22.04.00a220308
+# where cudf 220308 was chosen possibly because it has fewer/different
+# dependencies and the corresponding recipes think they're compatible when they
+# may not be.
 gpuci_mamba_retry install -y \
-      "libcudf=${MINOR_VERSION}" \
       "cudf=${MINOR_VERSION}" \
       "librmm=${MINOR_VERSION}" \
       "rmm=${MINOR_VERSION}" \

cpp/CMakeLists.txt

@@ -348,6 +348,7 @@ endif()
 
 add_library(cugraph_c SHARED
         src/c_api/cugraph_api.cpp
+        src/c_api/resource_handle.cpp
         src/c_api/array.cpp
         src/c_api/error.cpp
         src/c_api/graph_sg.cpp

cpp/cmake/thirdparty/get_raft.cmake

@@ -36,8 +36,9 @@ function(find_and_configure_raft)
             GIT_TAG        ${PKG_PINNED_TAG}
             SOURCE_SUBDIR  cpp
             OPTIONS
-                "BUILD_TESTS OFF"
                 "RAFT_COMPILE_LIBRARIES OFF"
+                "BUILD_TESTS OFF"
+                "BUILD_BENCH OFF"
     )
 
     if(raft_ADDED)

cpp/include/cugraph_c/algorithms.h

@@ -16,9 +16,9 @@
 
 #pragma once
 
-#include <cugraph_c/cugraph_api.h>
 #include <cugraph_c/error.h>
 #include <cugraph_c/graph.h>
+#include <cugraph_c/resource_handle.h>
 
 #ifdef __cplusplus
 extern "C" {

cpp/include/cugraph_c/array.h

@@ -16,26 +16,26 @@
 
 #pragma once
 
-#include <cugraph_c/cugraph_api.h>
+#include <cugraph_c/resource_handle.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 typedef struct {
-  int align_;
+  int32_t align_;
 } cugraph_type_erased_device_array_t;
 
 typedef struct {
-  int align_;
+  int32_t align_;
 } cugraph_type_erased_device_array_view_t;
 
 typedef struct {
-  int align_;
+  int32_t align_;
 } cugraph_type_erased_host_array_t;
 
 typedef struct {
-  int align_;
+  int32_t align_;
 } cugraph_type_erased_host_array_view_t;
 
 /**

cpp/include/cugraph_c/cugraph_api.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, NVIDIA CORPORATION.
+ * Copyright (c) 2021-2022, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,6 +17,7 @@
 #pragma once
 
 #include <cugraph_c/error.h>
+#include <cugraph_c/resource_handle.h>
 
 #include <cuda_runtime_api.h>
 #include <stddef.h>
@@ -26,21 +27,8 @@
 extern "C" {
 #endif
 
-typedef enum bool_ { FALSE = 0, TRUE = 1 } bool_t;
-
-typedef int8_t byte_t;
-
-typedef enum data_type_id_ { INT32 = 0, INT64, FLOAT32, FLOAT64, NTYPES } data_type_id_t;
-
-/* sizes in Bytes for data_type_id_t*/
-extern int data_type_sz[];
-
 /* C stub declarations */
 
-typedef struct cugraph_resource_handle_ {
-  int align_;
-} cugraph_resource_handle_t;
-
 typedef struct cugraph_graph_envelope_ {
   int align_;
 } cugraph_graph_envelope_t;
@@ -160,12 +148,6 @@ cugraph_error_code_t cugraph_update_host_buffer(const cugraph_resource_handle_t*
                                                 byte_t* ptr_h_dst,
                                                 const cugraph_device_buffer_t* ptr_src);
 
-/* raft::handle_t allocator (for now; possibly a more encompassing handle in the future)*/
-cugraph_resource_handle_t* cugraph_create_resource_handle(void);
-
-/* raft::handle_t deallocator*/
-void cugraph_free_resource_handle(cugraph_resource_handle_t* p_handle);
-
 #ifdef __cplusplus
 }
 #endif

cpp/include/cugraph_c/error.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, NVIDIA CORPORATION.
+ * Copyright (c) 2021-2022, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,8 @@
 
 #pragma once
 
+#include <stdint.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -31,7 +33,7 @@ typedef enum cugraph_error_code_ {
 } cugraph_error_code_t;
 
 typedef struct cugraph_error_ {
-  int align_;
+  int32_t align_;
 } cugraph_error_t;
 
 /**

cpp/include/cugraph_c/graph.h

@@ -24,14 +24,15 @@ extern "C" {
 #endif
 
 typedef struct {
-  int align_;
+  int32_t align_;
 } cugraph_graph_t;
 
 typedef struct {
   bool_t is_symmetric;
   bool_t is_multigraph;
 } cugraph_graph_properties_t;
 
+// FIXME: Add support for specifying isloated vertices
 /**
  * @brief     Construct an SG graph
  *
@@ -73,6 +74,7 @@ cugraph_error_code_t cugraph_sg_graph_create(const cugraph_resource_handle_t* ha
 //         but didn't want to confuse with original cugraph_free_graph
 void cugraph_sg_graph_free(cugraph_graph_t* graph);
 
+// FIXME: Add support for specifying isloated vertices
 /**
  * @brief     Construct an MG graph
  *
@@ -94,20 +96,16 @@ void cugraph_sg_graph_free(cugraph_graph_t* graph);
  *                          be populated if error code is not CUGRAPH_SUCCESS
  * @return error code
  */
-cugraph_error_code_t cugraph_mg_graph_create(
-  const cugraph_resource_handle_t* handle,
-  const cugraph_graph_properties_t* properties,
-  const cugraph_type_erased_device_array_view_t* src,
-  const cugraph_type_erased_device_array_view_t* dst,
-  const cugraph_type_erased_device_array_view_t* weights,
-  const cugraph_type_erased_host_array_view_t* vertex_partition_offsets,
-  const cugraph_type_erased_host_array_view_t* segment_offsets,
-  bool_t store_transposed,
-  size_t num_vertices,
-  size_t num_edges,
-  bool_t check,
-  cugraph_graph_t** graph,
-  cugraph_error_t** error);
+cugraph_error_code_t cugraph_mg_graph_create(const cugraph_resource_handle_t* handle,
+                                             const cugraph_graph_properties_t* properties,
+                                             const cugraph_type_erased_device_array_view_t* src,
+                                             const cugraph_type_erased_device_array_view_t* dst,
+                                             const cugraph_type_erased_device_array_view_t* weights,
+                                             bool_t store_transposed,
+                                             size_t num_edges,
+                                             bool_t check,
+                                             cugraph_graph_t** graph,
+                                             cugraph_error_t** error);
 
 /**
  * @brief     Destroy an MG graph

cpp/include/cugraph_c/resource_handle.h

@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2022, NVIDIA CORPORATION.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <cugraph_c/error.h>
+
+#include <stddef.h>
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef enum bool_ { FALSE = 0, TRUE = 1 } bool_t;
+
+typedef int8_t byte_t;
+
+typedef enum data_type_id_ { INT32 = 0, INT64, FLOAT32, FLOAT64, NTYPES } data_type_id_t;
+
+/* sizes in Bytes for data_type_id_t*/
+extern size_t data_type_sz[];
+
+typedef struct cugraph_resource_handle_ {
+  int32_t align_;
+} cugraph_resource_handle_t;
+
+// FIXME: Don't really want a raft handle here.  We really want to be able to
+//        configure the resource handle ourselves.  But that requires a bunch
+//        of logic that's currently only available in python.
+/**
+ * @brief     Construct a resource handle
+ *
+ * @param [in]  raft_handle   Handle for accessing resources
+ *                            If NULL, we will create a raft handle
+ *                            internally
+ *
+ * @return A graph resource handle
+ */
+cugraph_resource_handle_t* cugraph_create_resource_handle(void* raft_handle);
+
+/**
+ * @brief get rank from resource handle
+ *
+ * If the resource handle has been configured for multi-gpu, this will return
+ * the rank for this worker.  If the resource handle has not been configured for
+ * multi-gpu this will always return 0.
+ *
+ * @param [in]  handle          Handle for accessing resources
+ * @return rank
+ */
+int cugraph_resource_handle_get_rank(const cugraph_resource_handle_t* handle);
+
+/**
+ * @brief     Free resources in the resource handle
+ *
+ * @param [in]  handle          Handle for accessing resources
+ */
+void cugraph_free_resource_handle(cugraph_resource_handle_t* handle);
+
+#ifdef __cplusplus
+}
+#endif