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From: Jussi Kivilinna <jussi.kivilinna@iki.fi>
To: "John W. Linville" <linville@tuxdriver.com>
Cc: linux-wireless@vger.kernel.org,
	Chaoming Li <chaoming_li@realsil.com.cn>,
	Larry Finger <Larry.Finger@lwfinger.net>
Subject: Re: [PATCH 0/4] rtlwifi: usb: improve RX performance and lower CPU usage
Date: Wed, 03 Apr 2013 22:19:06 +0300	[thread overview]
Message-ID: <515C80AA.6090409@iki.fi> (raw)
In-Reply-To: <20130403173248.GA14611@tuxdriver.com>

On 03.04.2013 20:32, John W. Linville wrote:
> They are in wireless-next...

Ah, thanks!

-Jussi

> 
> commit 657e27656dfb3a99e81c99df6e78e770d7fe0d48
> Author: Jussi Kivilinna <jussi.kivilinna@iki.fi>
> Date:   Sun Mar 17 11:59:29 2013 +0200
> 
>     rtlwifi: usb: add NET_IP_ALIGN padding to RX skb when needed
>     
>     Add proper alignment at first packet copy, to avoid extra copies made later
>     in networking stack.
>     
>     Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
>     Signed-off-by: John W. Linville <linville@tuxdriver.com>
> 
> commit 29bb7013a53d8fc43f79f39d22a15ba8d3e77d9b
> Author: Jussi Kivilinna <jussi.kivilinna@iki.fi>
> Date:   Sun Mar 17 11:59:24 2013 +0200
> 
>     rtlwifi: usb: defer rx processing to tasklet
>     
>     Move processing of received packets to tasklet from hard-irq context.
>     
>     Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
>     Signed-off-by: John W. Linville <linville@tuxdriver.com>
> 
> commit d7d0f081c48951018133cac38c8c0796f37db727
> Author: Jussi Kivilinna <jussi.kivilinna@iki.fi>
> Date:   Sun Mar 17 11:59:18 2013 +0200
> 
>     rtlwifi: usb: remove extra skb copy on RX path
>     
>     RX path has extra copying of packets, that can be avoided.
>     
>     Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
>     Signed-off-by: John W. Linville <linville@tuxdriver.com>
> 
> commit 872de8ff04922e4ad95c5af39131ae9fbefe6ac5
> Author: Jussi Kivilinna <jussi.kivilinna@iki.fi>
> Date:   Sun Mar 17 11:59:13 2013 +0200
> 
>     rtlwifi: usb: use usb_alloc_coherent for RX buffers
>     
>     Use dedicated DMA coherent buffers for RX urbs, to avoid allocation of large
>     skbuffs in hard-irq context and improve performance.
>     
>     Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
>     Signed-off-by: John W. Linville <linville@tuxdriver.com>
> 
> On Wed, Apr 03, 2013 at 08:16:20PM +0300, Jussi Kivilinna wrote:
>> Any comments on this patchset?
>>
>> On 17.03.2013 11:59, Jussi Kivilinna wrote:
>>> Patchset improves RX path handling in rtlwifi/usb.c by:
>>>  - change to use preallocated DMA coherent URB buffers.
>>>  - kill unnessasary skbuff copies.
>>>  - defer RX processing to tasklet.
>>>  - add proper alignment of skbuff early on.
>>>
>>> With this patchset IRQ CPU usage drops from 37% to 25% on ARM system with
>>> 1Ghz Cortex-A8, when doing large transfer with rtl8192cu. Tranfer speed
>>> appears to be slightly improved too, from 29Mbit to 31Mbit.
>>>
>>> ---
>>>
>>> Jussi Kivilinna (4):
>>>       rtlwifi: usb: use usb_alloc_coherent for RX buffers
>>>       rtlwifi: usb: remove extra skb copy on RX path
>>>       rtlwifi: usb: defer rx processing to tasklet
>>>       rtlwifi: usb: add NET_IP_ALIGN padding to RX skb when needed
>>>
>>>
>>>  drivers/net/wireless/rtlwifi/rtl8192cu/trx.c |    2
>>>  drivers/net/wireless/rtlwifi/usb.c           |  220 ++++++++++++++++++--------
>>>  drivers/net/wireless/rtlwifi/usb.h           |    5 -
>>>  3 files changed, 156 insertions(+), 71 deletions(-)
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>
> 


      reply	other threads:[~2013-04-03 19:19 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-17  9:59 [PATCH 0/4] rtlwifi: usb: improve RX performance and lower CPU usage Jussi Kivilinna
2013-03-17  9:59 ` [PATCH 1/4] rtlwifi: usb: use usb_alloc_coherent for RX buffers Jussi Kivilinna
2013-03-17  9:59 ` [PATCH 2/4] rtlwifi: usb: remove extra skb copy on RX path Jussi Kivilinna
2013-03-17  9:59 ` [PATCH 3/4] rtlwifi: usb: defer rx processing to tasklet Jussi Kivilinna
2013-03-17  9:59 ` [PATCH 4/4] rtlwifi: usb: add NET_IP_ALIGN padding to RX skb when needed Jussi Kivilinna
2013-04-03 17:16 ` [PATCH 0/4] rtlwifi: usb: improve RX performance and lower CPU usage Jussi Kivilinna
2013-04-03 17:32   ` John W. Linville
2013-04-03 19:19     ` Jussi Kivilinna [this message]

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