From: jszhang@marvell.com (Jisheng Zhang)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] net: mvneta: remove useless RX descriptor prefetch
Date: Thu, 31 Mar 2016 14:45:37 +0800 [thread overview]
Message-ID: <20160331144537.20f04a8c@xhacker> (raw)
In-Reply-To: <1459406190-2334-1-git-send-email-jszhang@marvell.com>
Hi,
+ linux arm kernel
On Thu, 31 Mar 2016 14:36:30 +0800 Jisheng Zhang wrote:
> The rx descriptors are allocated using dma_alloc_coherent, so prefetch
> doesn't really happen at all.
This is for RFC, I'm sorry to send it without changing its title -- s/PATCH/RFC.
I'm not sure whether there's any benefit to prefetch on space allocated from
dma_alloc_coherent.
Thanks
>
> Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> ---
> drivers/net/ethernet/marvell/mvneta.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
> index 5880871..6c09a27 100644
> --- a/drivers/net/ethernet/marvell/mvneta.c
> +++ b/drivers/net/ethernet/marvell/mvneta.c
> @@ -757,7 +757,6 @@ mvneta_rxq_next_desc_get(struct mvneta_rx_queue *rxq)
> int rx_desc = rxq->next_desc_to_proc;
>
> rxq->next_desc_to_proc = MVNETA_QUEUE_NEXT_DESC(rxq, rx_desc);
> - prefetch(rxq->descs + rxq->next_desc_to_proc);
> return rxq->descs + rx_desc;
> }
>
WARNING: multiple messages have this Message-ID (diff)
From: Jisheng Zhang <jszhang@marvell.com>
To: <thomas.petazzoni@free-electrons.com>,
<gregory.clement@free-electrons.com>, <davem@davemloft.net>
Cc: <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH] net: mvneta: remove useless RX descriptor prefetch
Date: Thu, 31 Mar 2016 14:45:37 +0800 [thread overview]
Message-ID: <20160331144537.20f04a8c@xhacker> (raw)
In-Reply-To: <1459406190-2334-1-git-send-email-jszhang@marvell.com>
Hi,
+ linux arm kernel
On Thu, 31 Mar 2016 14:36:30 +0800 Jisheng Zhang wrote:
> The rx descriptors are allocated using dma_alloc_coherent, so prefetch
> doesn't really happen at all.
This is for RFC, I'm sorry to send it without changing its title -- s/PATCH/RFC.
I'm not sure whether there's any benefit to prefetch on space allocated from
dma_alloc_coherent.
Thanks
>
> Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> ---
> drivers/net/ethernet/marvell/mvneta.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
> index 5880871..6c09a27 100644
> --- a/drivers/net/ethernet/marvell/mvneta.c
> +++ b/drivers/net/ethernet/marvell/mvneta.c
> @@ -757,7 +757,6 @@ mvneta_rxq_next_desc_get(struct mvneta_rx_queue *rxq)
> int rx_desc = rxq->next_desc_to_proc;
>
> rxq->next_desc_to_proc = MVNETA_QUEUE_NEXT_DESC(rxq, rx_desc);
> - prefetch(rxq->descs + rxq->next_desc_to_proc);
> return rxq->descs + rx_desc;
> }
>
next prev parent reply other threads:[~2016-03-31 6:45 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-31 6:36 [PATCH] net: mvneta: remove useless RX descriptor prefetch Jisheng Zhang
2016-03-31 6:45 ` Jisheng Zhang [this message]
2016-03-31 6:45 ` Jisheng Zhang
2016-03-31 7:15 ` Jisheng Zhang
2016-03-31 7:15 ` Jisheng Zhang
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