[Java][C] Expose GPUInfo

java/cuvs-java/src/main/java/com/nvidia/cuvs/CuVSResources.java

@@ -49,6 +49,13 @@ interface ScopedAccess extends AutoCloseable {
    */
   ScopedAccess access();
 
+  /**
+   * Get the logical id of the device associated with this resources object.
+   * Information about the device id is immutable, so it is safe to expose it without getting {@link ScopedAccess}
+   * to the enclosing resources.
+   */
+  int deviceId();
+
   /**
    * Closes this CuVSResources object and releases any resources associated with it.
    */

java/cuvs-java/src/main/java/com/nvidia/cuvs/SynchronizedCuVSResources.java

@@ -51,6 +51,11 @@ public void close() {
     };
   }
 
+  @Override
+  public int deviceId() {
+    return inner.deviceId();
+  }
+
   @Override
   public void close() {
     inner.close();

java/cuvs-java/src/main/java22/com/nvidia/cuvs/internal/CuVSResourcesImpl.java

@@ -16,9 +16,8 @@
 package com.nvidia.cuvs.internal;
 
 import static com.nvidia.cuvs.internal.common.Util.checkCuVSError;
-import static com.nvidia.cuvs.internal.panama.headers_h.cuvsResourcesCreate;
-import static com.nvidia.cuvs.internal.panama.headers_h.cuvsResourcesDestroy;
-import static com.nvidia.cuvs.internal.panama.headers_h.cuvsResources_t;
+import static com.nvidia.cuvs.internal.panama.headers_h.*;
+import static com.nvidia.cuvs.internal.panama.headers_h_1.C_INT;
 
 import com.nvidia.cuvs.CuVSResources;
 import java.lang.foreign.Arena;
@@ -34,6 +33,7 @@ public class CuVSResourcesImpl implements CuVSResources {
   private final Path tempDirectory;
   private final long resourceHandle;
   private final ScopedAccess access;
+  private final int deviceId;
 
   /**
    * Constructor that allocates the resources needed for cuVS
@@ -43,9 +43,11 @@ public CuVSResourcesImpl(Path tempDirectory) {
     this.tempDirectory = tempDirectory;
     try (var localArena = Arena.ofConfined()) {
       var resourcesMemorySegment = localArena.allocate(cuvsResources_t);
-      int returnValue = cuvsResourcesCreate(resourcesMemorySegment);
-      checkCuVSError(returnValue, "cuvsResourcesCreate");
+      checkCuVSError(cuvsResourcesCreate(resourcesMemorySegment), "cuvsResourcesCreate");
       this.resourceHandle = resourcesMemorySegment.get(cuvsResources_t, 0);
+      var deviceIdPtr = localArena.allocate(C_INT);
+      checkCuVSError(cuvsDeviceIdGet(resourceHandle, deviceIdPtr), "cuvsDeviceIdGet");
+      this.deviceId = deviceIdPtr.get(C_INT, 0);
       this.access =
           new ScopedAccess() {
             @Override
@@ -64,6 +66,11 @@ public ScopedAccess access() {
     return this.access;
   }
 
+  @Override
+  public int deviceId() {
+    return this.deviceId;
+  }
+
   @Override
   public void close() {
     synchronized (this) {

java/cuvs-java/src/main/java22/com/nvidia/cuvs/internal/GPUInfoProviderImpl.java

@@ -15,10 +15,8 @@
  */
 package com.nvidia.cuvs.internal;
 
-import static com.nvidia.cuvs.internal.common.Util.checkCuVSError;
 import static com.nvidia.cuvs.internal.common.Util.checkCudaError;
 import static com.nvidia.cuvs.internal.panama.headers_h.cudaMemGetInfo;
-import static com.nvidia.cuvs.internal.panama.headers_h.cuvsDeviceIdGet;
 import static com.nvidia.cuvs.internal.panama.headers_h_1.*;
 
 import com.nvidia.cuvs.CuVSResources;
@@ -45,29 +43,24 @@ public List<GPUInfo> compatibleGPUs() throws Throwable {
 
   @Override
   public CuVSResourcesInfo getCurrentInfo(CuVSResources resources) {
-    try (var resourcesAccess = resources.access()) {
-      try (var localArena = Arena.ofConfined()) {
-        var deviceIdPtr = localArena.allocate(C_INT);
-        checkCudaError(cudaGetDevice(deviceIdPtr), "cudaGetDevice");
-        var currentDeviceId = deviceIdPtr.get(C_INT, 0);
+    try (var localArena = Arena.ofConfined()) {
+      var deviceIdPtr = localArena.allocate(C_INT);
+      checkCudaError(cudaGetDevice(deviceIdPtr), "cudaGetDevice");
+      var currentDeviceId = deviceIdPtr.get(C_INT, 0);
 
-        checkCuVSError(cuvsDeviceIdGet(resourcesAccess.handle(), deviceIdPtr), "cuvsDeviceIdGet");
-        var resourcesDeviceId = deviceIdPtr.get(C_INT, 0);
-
-        if (resourcesDeviceId != currentDeviceId) {
-          checkCudaError(cudaSetDevice(resourcesDeviceId), "cudaSetDevice");
-        }
-
-        MemorySegment freeMemoryPtr = localArena.allocate(size_t);
-        MemorySegment totalMemoryPtr = localArena.allocate(size_t);
-        checkCudaError(cudaMemGetInfo(freeMemoryPtr, totalMemoryPtr), "cudaMemGetInfo");
+      if (resources.deviceId() != currentDeviceId) {
+        checkCudaError(cudaSetDevice(resources.deviceId()), "cudaSetDevice");
+      }
 
-        if (resourcesDeviceId != currentDeviceId) {
-          checkCudaError(cudaSetDevice(currentDeviceId), "cudaSetDevice");
-        }
+      MemorySegment freeMemoryPtr = localArena.allocate(size_t);
+      MemorySegment totalMemoryPtr = localArena.allocate(size_t);
+      checkCudaError(cudaMemGetInfo(freeMemoryPtr, totalMemoryPtr), "cudaMemGetInfo");
 
-        return new CuVSResourcesInfo(freeMemoryPtr.get(size_t, 0), totalMemoryPtr.get(size_t, 0));
+      if (resources.deviceId() != currentDeviceId) {
+        checkCudaError(cudaSetDevice(currentDeviceId), "cudaSetDevice");
       }
+
+      return new CuVSResourcesInfo(freeMemoryPtr.get(size_t, 0), totalMemoryPtr.get(size_t, 0));
     }
   }
 }

java/cuvs-java/src/test/java/com/nvidia/cuvs/CheckedCuVSResources.java

@@ -61,6 +61,11 @@ public void close() {
     };
   }
 
+  @Override
+  public int deviceId() {
+    return inner.deviceId();
+  }
+
   @Override
   public void close() {
     destroyed = true;