Function gemm_batched_with 

pub fn gemm_batched_with<T: GemmScalar>(
    ws: &mut Workspace,
    batch: usize,
    alpha: T,
    a: MatRef<'_, T>,
    a_batch_stride: isize,
    b: MatRef<'_, T>,
    b_batch_stride: isize,
    beta: T,
    c: MatMut<'_, T>,
    c_batch_stride: isize,
    par: Parallelism,
)

Like gemm_batched but reuses a caller-owned Workspace across calls. The serial and few-but-large schedules pack through ws. The batch-parallel schedule instead has each worker pack through its own thread-local pool, since 1 Workspace cannot back concurrent packing from several threads

Panics

Same conditions as gemm_batched