Re: [PATCH v4 6/9] nvmet: pci-epf: Remove unnecessary dmaengine_terminate_sync() on each DMA transfer

On Wed, May 06, 2026 at 04:44:18PM -0400, Frank Li wrote:
> dmaengine_terminate_sync() cancels all pending requests. Calling it for
> every DMA transfer is unnecessary and counterproductive. This function is
> generally intended for cleanup paths such as module removal, device close,
> or unbind operations.
> 
> Remove the redundant calls for success path and keep it only at error path.
> 
> Tested-by: Niklas Cassel <[email protected]>
> Reviewed-by: Damien Le Moal <[email protected]>
> Signed-off-by: Frank Li <[email protected]>

Acked-by: Manivannan Sadhasivam <[email protected]>

- Mani

> ---
> This one also fix stress test failure after remove mutex and use new API
> dmaengine_prep_slave_sg_config().
> ---
>  drivers/nvme/target/pci-epf.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/nvme/target/pci-epf.c b/drivers/nvme/target/pci-epf.c
> index 4e9db96ebfecd796244e5dc67c23e1abb1a14974..2afe8f4d0e46104a1b3c98db3905cf33e8c9e011 100644
> --- a/drivers/nvme/target/pci-epf.c
> +++ b/drivers/nvme/target/pci-epf.c
> @@ -420,10 +420,9 @@ static int nvmet_pci_epf_dma_transfer(struct nvmet_pci_epf *nvme_epf,
>  	if (dma_sync_wait(chan, cookie) != DMA_COMPLETE) {
>  		dev_err(dev, "DMA transfer failed\n");
>  		ret = -EIO;
> +		dmaengine_terminate_sync(chan);
>  	}
>  
> -	dmaengine_terminate_sync(chan);
> -
>  unmap:
>  	dma_unmap_single(dma_dev, dma_addr, seg->length, dir);
>  
> 
> -- 
> 2.43.0
> 

-- 
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