Function model_close

ds4.c:1823–1831

        pthread_mutex_unlock(&g_pool.mutex);

        const uint64_t rows_per_thread = (n_rows + n_threads - 1) / n_threads;
        const uint64_t row0 = (uint64_t)tid * rows_per_thread;
        uint64_t row1 = row0 + rows_per_thread;
        if (row1 > n_rows) row1 = n_rows;
        if (row0 < row1) {
            g_parallel_depth++;
            fn(ctx, row0, row1);
            g_parallel_depth--;
        }

        pthread_mutex_lock(&g_pool.mutex);
        g_pool.done++;