[gcc r15-8867] libgomp/plugin/plugin-nvptx.c: Fix device used for stream creation

[Tobias Burnus via Gcc-cvs]

https://gcc.gnu.org/g:1c5a375c21a262eb636449f88e671a09e140404e

commit r15-8867-g1c5a375c21a262eb636449f88e671a09e140404e
Author: Tobias Burnus <tbur...@baylibre.com>
Date:   Mon Mar 24 16:08:20 2025 +0100

    libgomp/plugin/plugin-nvptx.c: Fix device used for stream creation
    
    libgomp/ChangeLog:
    
            * plugin/plugin-nvptx.c (GOMP_OFFLOAD_interop): Set context for
            stream creation to use the specified device.

Diff:
---
 libgomp/plugin/plugin-nvptx.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/libgomp/plugin/plugin-nvptx.c b/libgomp/plugin/plugin-nvptx.c
index 822c6a410e28..a5cf859db197 100644
--- a/libgomp/plugin/plugin-nvptx.c
+++ b/libgomp/plugin/plugin-nvptx.c
@@ -2483,12 +2483,26 @@ GOMP_OFFLOAD_interop (struct interop_obj_t *obj, int 
ord,
          break;
       }
 
-  obj->device_data = ptx_devices[ord];
+  struct ptx_device *ptx_dev = obj->device_data = ptx_devices[ord];
 
   if (targetsync)
     {
       CUstream stream = NULL;
-      CUDA_CALL_ASSERT (cuStreamCreate, &stream, CU_STREAM_DEFAULT);
+      CUdevice cur_ctx_dev;
+      CUresult res = CUDA_CALL_NOCHECK (cuCtxGetDevice, &cur_ctx_dev);
+      if (res != CUDA_SUCCESS && res != CUDA_ERROR_INVALID_CONTEXT)
+       GOMP_PLUGIN_fatal ("cuCtxGetDevice error: %s", cuda_error (res));
+      if (res != CUDA_ERROR_INVALID_CONTEXT && ptx_dev->dev == cur_ctx_dev)
+       CUDA_CALL_ASSERT (cuStreamCreate, &stream, CU_STREAM_DEFAULT);
+      else
+       {
+         CUcontext old_ctx;
+         assert (ptx_dev->ctx);
+         CUDA_CALL_ASSERT (cuCtxPushCurrent, ptx_dev->ctx);
+         CUDA_CALL_ASSERT (cuStreamCreate, &stream, CU_STREAM_DEFAULT);
+         if (res != CUDA_ERROR_INVALID_CONTEXT)
+           CUDA_CALL_ASSERT (cuCtxPopCurrent, &old_ctx);
+       }
       obj->stream = stream;
     }
 }