opal/mca/common/ucx : assert fix - change thread mode sent to UCX api #13590
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Signed-off-by: Nathan Bellalou <nbellalou@nvidia.com>
bosilca
approved these changes
Dec 23, 2025
| memset(&worker_params, 0, sizeof(worker_params)); | ||
| worker_params.field_mask = UCP_WORKER_PARAM_FIELD_THREAD_MODE; | ||
| worker_params.thread_mode = UCS_THREAD_MODE_SINGLE; | ||
| worker_params.thread_mode = ompi_mpi_thread_provided == MPI_THREAD_SINGLE ? UCS_THREAD_MODE_SINGLE : UCS_THREAD_MODE_SERIALIZED; |
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if the user initialized MPI with MPI_THREAD_MULTIPLE, will this be passed correctly to the initialization of the UCX worker when creating a window? I am not sure this fix here correctly captures this (or fixes it), see #13347
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UCP Worker Thread Modes in OpenUCX define how multiple threads interact with a UCP worker.
UCS_THREAD_MODE_SINGLEindicates that only one unique thread can use this worker throughout the whole application.In a multithreaded application, OMPI may reuse
winfoobjects among different threads, conflicting with hard-codedUCS_THREAD_MODE_SINGLE, and resulting in an assert failureIf an application use multiple threads, we want to use parameter
UCS_THREAD_MODE_SERIALIZEDthat allows different threads to use the same worker successively