From: Ilias Apalodimas <ilias.apalodimas@linaro.org>
To: Jose Abreu <Jose.Abreu@synopsys.com>
Cc: Joao Pinto <Joao.Pinto@synopsys.com>,
Alexandre Torgue <alexandre.torgue@st.com>,
Maxime Ripard <maxime.ripard@bootlin.com>,
"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"David S . Miller" <davem@davemloft.net>,
Chen-Yu Tsai <wens@csie.org>,
Maxime Coquelin <mcoquelin.stm32@gmail.com>,
Jesper Dangaard Brouer <brouer@redhat.com>,
Giuseppe Cavallaro <peppe.cavallaro@st.com>,
"linux-stm32@st-md-mailman.stormreply.com"
<linux-stm32@st-md-mailman.stormreply.com>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH net-next 3/3] net: stmmac: Introducing support for Page Pool
Date: Thu, 4 Jul 2019 14:11:09 +0300 [thread overview]
Message-ID: <20190704111109.GA12011@apalos> (raw)
In-Reply-To: <BN8PR12MB3266BC5322AADFAC49D9BAFAD3FA0@BN8PR12MB3266.namprd12.prod.outlook.com>
On Thu, Jul 04, 2019 at 10:13:37AM +0000, Jose Abreu wrote:
> From: Jesper Dangaard Brouer <brouer@redhat.com>
>
> > The page_pool DMA mapping cannot be "kept" when page traveling into the
> > network stack attached to an SKB. (Ilias and I have a long term plan[1]
> > to allow this, but you cannot do it ATM).
>
> The reason I recycle the page is this previous call to:
>
> skb_copy_to_linear_data()
>
> So, technically, I'm syncing to CPU the page(s) and then memcpy to a
> previously allocated SKB ... So it's safe to just recycle the mapping I
> think.
>
> Its kind of using bounce buffers and I do see performance gain in this
> (I think the reason is because my setup uses swiotlb for DMA mapping).
Maybe. Have you tested this on big/small packets?
Can you do a test with 64b/128b and 1024b for example?
The memcpy might be cheap for the small sized packets (and cheaper than the dma
map/unmap)
>
> Anyway, I'm open to some suggestions on how to improve this ...
>
> > Also remember that the page_pool requires you driver to do the DMA-sync
> > operation. I see a dma_sync_single_for_cpu(), but I didn't see a
> > dma_sync_single_for_device() (well, I noticed one getting removed).
> > (For some HW Ilias tells me that the dma_sync_single_for_device can be
> > elided, so maybe this can still be correct for you).
>
> My HW just needs descriptors refilled which are in different coherent
> region so I don't see any reason for dma_sync_single_for_device() ...
I am abit overloaded at the moment. I'll try to have a look at this and get back
to you
Cheers
/Ilias
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
WARNING: multiple messages have this Message-ID (diff)
From: Ilias Apalodimas <ilias.apalodimas@linaro.org>
To: Jose Abreu <Jose.Abreu@synopsys.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
"linux-stm32@st-md-mailman.stormreply.com"
<linux-stm32@st-md-mailman.stormreply.com>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>,
Joao Pinto <Joao.Pinto@synopsys.com>,
"David S . Miller" <davem@davemloft.net>,
Giuseppe Cavallaro <peppe.cavallaro@st.com>,
Alexandre Torgue <alexandre.torgue@st.com>,
Maxime Coquelin <mcoquelin.stm32@gmail.com>,
Maxime Ripard <maxime.ripard@bootlin.com>,
Chen-Yu Tsai <wens@csie.org>
Subject: Re: [PATCH net-next 3/3] net: stmmac: Introducing support for Page Pool
Date: Thu, 4 Jul 2019 14:11:09 +0300 [thread overview]
Message-ID: <20190704111109.GA12011@apalos> (raw)
In-Reply-To: <BN8PR12MB3266BC5322AADFAC49D9BAFAD3FA0@BN8PR12MB3266.namprd12.prod.outlook.com>
On Thu, Jul 04, 2019 at 10:13:37AM +0000, Jose Abreu wrote:
> From: Jesper Dangaard Brouer <brouer@redhat.com>
>
> > The page_pool DMA mapping cannot be "kept" when page traveling into the
> > network stack attached to an SKB. (Ilias and I have a long term plan[1]
> > to allow this, but you cannot do it ATM).
>
> The reason I recycle the page is this previous call to:
>
> skb_copy_to_linear_data()
>
> So, technically, I'm syncing to CPU the page(s) and then memcpy to a
> previously allocated SKB ... So it's safe to just recycle the mapping I
> think.
>
> Its kind of using bounce buffers and I do see performance gain in this
> (I think the reason is because my setup uses swiotlb for DMA mapping).
Maybe. Have you tested this on big/small packets?
Can you do a test with 64b/128b and 1024b for example?
The memcpy might be cheap for the small sized packets (and cheaper than the dma
map/unmap)
>
> Anyway, I'm open to some suggestions on how to improve this ...
>
> > Also remember that the page_pool requires you driver to do the DMA-sync
> > operation. I see a dma_sync_single_for_cpu(), but I didn't see a
> > dma_sync_single_for_device() (well, I noticed one getting removed).
> > (For some HW Ilias tells me that the dma_sync_single_for_device can be
> > elided, so maybe this can still be correct for you).
>
> My HW just needs descriptors refilled which are in different coherent
> region so I don't see any reason for dma_sync_single_for_device() ...
I am abit overloaded at the moment. I'll try to have a look at this and get back
to you
Cheers
/Ilias
next prev parent reply other threads:[~2019-07-04 11:11 UTC|newest]
Thread overview: 183+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-03 10:37 [PATCH net-next 0/3] net: stmmac: Some performance improvements and a fix Jose Abreu
2019-07-03 10:37 ` Jose Abreu
2019-07-03 10:37 ` [PATCH net-next 1/3] net: stmmac: Implement RX Coalesce Frames setting Jose Abreu
2019-07-03 10:37 ` Jose Abreu
2019-07-03 20:41 ` Jakub Kicinski
2019-07-03 20:41 ` Jakub Kicinski
2019-07-03 10:37 ` [PATCH net-next 2/3] net: stmmac: Fix descriptors address being in > 32 bits address space Jose Abreu
2019-07-03 10:37 ` Jose Abreu
2019-07-03 10:37 ` [PATCH net-next 3/3] net: stmmac: Introducing support for Page Pool Jose Abreu
2019-07-03 10:37 ` Jose Abreu
2019-07-03 10:40 ` Jose Abreu
2019-07-03 10:40 ` Jose Abreu
2019-07-04 9:39 ` Jesper Dangaard Brouer
2019-07-04 9:39 ` Jesper Dangaard Brouer
2019-07-04 14:45 ` Jose Abreu
2019-07-04 14:45 ` Jose Abreu
2019-07-04 15:09 ` Jesper Dangaard Brouer
2019-07-04 15:09 ` Jesper Dangaard Brouer
2019-07-04 15:18 ` Jose Abreu
2019-07-04 15:18 ` Jose Abreu
2019-07-04 15:33 ` Jesper Dangaard Brouer
2019-07-04 15:33 ` Jesper Dangaard Brouer
2019-07-04 9:48 ` Jesper Dangaard Brouer
2019-07-04 9:48 ` Jesper Dangaard Brouer
2019-07-04 10:00 ` Jesper Dangaard Brouer
2019-07-04 10:00 ` Jesper Dangaard Brouer
2019-07-04 10:13 ` Jose Abreu
2019-07-04 10:13 ` Jose Abreu
2019-07-04 11:11 ` Ilias Apalodimas [this message]
2019-07-04 11:11 ` Ilias Apalodimas
2019-07-04 11:54 ` Jesper Dangaard Brouer
2019-07-04 11:54 ` Jesper Dangaard Brouer
2019-07-04 12:04 ` Ilias Apalodimas
2019-07-04 12:04 ` Ilias Apalodimas
2019-07-04 12:59 ` Jose Abreu
2019-07-04 12:59 ` Jose Abreu
2019-07-04 13:06 ` Ilias Apalodimas
2019-07-04 13:06 ` Ilias Apalodimas
2019-07-04 10:30 ` Ilias Apalodimas
2019-07-04 10:30 ` Ilias Apalodimas
2019-07-04 12:14 ` Arnd Bergmann
2019-07-04 12:14 ` Arnd Bergmann
2019-07-04 12:49 ` Ilias Apalodimas
2019-07-04 12:49 ` Ilias Apalodimas
2019-07-17 18:58 ` Jon Hunter
2019-07-17 18:58 ` Jon Hunter
2019-07-17 18:58 ` Jon Hunter
2019-07-18 7:29 ` Jose Abreu
2019-07-18 7:29 ` Jose Abreu
2019-07-18 7:48 ` Jose Abreu
2019-07-18 7:48 ` Jose Abreu
2019-07-18 9:16 ` Jon Hunter
2019-07-18 9:16 ` Jon Hunter
2019-07-19 7:51 ` Jose Abreu
2019-07-19 7:51 ` Jose Abreu
2019-07-19 8:37 ` Jon Hunter
2019-07-19 8:37 ` Jon Hunter
2019-07-19 8:44 ` Jose Abreu
2019-07-19 8:44 ` Jose Abreu
2019-07-19 8:49 ` Jon Hunter
2019-07-19 8:49 ` Jon Hunter
2019-07-19 10:25 ` Jose Abreu
2019-07-19 10:25 ` Jose Abreu
2019-07-19 12:28 ` Jose Abreu
2019-07-19 12:28 ` Jose Abreu
2019-07-19 13:33 ` Jon Hunter
2019-07-19 13:33 ` Jon Hunter
2019-07-19 12:30 ` Jon Hunter
2019-07-19 12:30 ` Jon Hunter
2019-07-19 12:32 ` Jose Abreu
2019-07-19 12:32 ` Jose Abreu
2019-07-19 13:35 ` Jon Hunter
2019-07-22 7:23 ` Jose Abreu
2019-07-22 7:23 ` Jose Abreu
2019-07-22 9:37 ` Jon Hunter
2019-07-22 9:37 ` Jon Hunter
2019-07-22 9:47 ` Jose Abreu
2019-07-22 9:47 ` Jose Abreu
2019-07-22 9:47 ` Jose Abreu
2019-07-22 9:57 ` Jose Abreu
2019-07-22 9:57 ` Jose Abreu
2019-07-22 10:27 ` Jon Hunter
2019-07-22 10:27 ` Jon Hunter
2019-07-22 10:18 ` Ilias Apalodimas
2019-07-22 10:18 ` Ilias Apalodimas
2019-07-22 11:11 ` Lars Persson
2019-07-22 11:11 ` Lars Persson
2019-07-22 11:39 ` Jose Abreu
2019-07-22 11:39 ` Jose Abreu
2019-07-22 12:05 ` Jon Hunter
2019-07-22 12:05 ` Jon Hunter
2019-07-22 14:04 ` Jose Abreu
2019-07-22 14:04 ` Jose Abreu
2019-07-22 14:04 ` Jose Abreu
2019-07-23 8:14 ` Jose Abreu
2019-07-23 8:14 ` Jose Abreu
2019-07-23 10:01 ` Jon Hunter
2019-07-23 10:01 ` Jon Hunter
2019-07-23 10:07 ` Jose Abreu
2019-07-23 10:07 ` Jose Abreu
2019-07-23 10:29 ` Robin Murphy
2019-07-23 10:29 ` Robin Murphy
2019-07-23 11:22 ` Jose Abreu
2019-07-23 11:22 ` Jose Abreu
2019-07-23 12:09 ` Jon Hunter
2019-07-23 12:09 ` Jon Hunter
2019-07-23 13:19 ` Robin Murphy
2019-07-23 13:19 ` Robin Murphy
2019-07-23 21:39 ` Jon Hunter
2019-07-23 21:39 ` Jon Hunter
2019-07-24 10:03 ` Robin Murphy
2019-07-24 10:03 ` Robin Murphy
2019-07-23 18:51 ` David Miller
2019-07-23 18:51 ` David Miller
2019-07-24 8:54 ` Ilias Apalodimas
2019-07-24 8:54 ` Ilias Apalodimas
2019-07-24 9:43 ` Jose Abreu
2019-07-24 9:43 ` Jose Abreu
2019-07-24 9:43 ` Jose Abreu
2019-07-24 9:53 ` Ilias Apalodimas
2019-07-24 9:53 ` Ilias Apalodimas
2019-07-24 9:53 ` Ilias Apalodimas
2019-07-24 10:04 ` Jose Abreu
2019-07-24 10:04 ` Jose Abreu
2019-07-24 10:04 ` Jose Abreu
2019-07-24 11:10 ` Jon Hunter
2019-07-24 11:10 ` Jon Hunter
2019-07-24 11:34 ` Jose Abreu
2019-07-24 11:34 ` Jose Abreu
2019-07-24 11:58 ` Jon Hunter
2019-07-24 11:58 ` Jon Hunter
2019-07-25 7:44 ` Jose Abreu
2019-07-25 7:44 ` Jose Abreu
2019-07-25 9:45 ` Jon Hunter
2019-07-25 9:45 ` Jon Hunter
2019-07-25 11:39 ` Ilias Apalodimas
2019-07-25 11:39 ` Ilias Apalodimas
2019-07-25 11:39 ` Ilias Apalodimas
2019-07-23 10:38 ` Jon Hunter
2019-07-23 10:38 ` Jon Hunter
2019-07-23 10:49 ` Jose Abreu
2019-07-23 10:49 ` Jose Abreu
2019-07-23 11:58 ` Jon Hunter
2019-07-23 11:58 ` Jon Hunter
2019-07-23 12:51 ` Jose Abreu
2019-07-23 12:51 ` Jose Abreu
2019-07-23 13:34 ` Jon Hunter
2019-07-23 13:34 ` Jon Hunter
2019-07-29 9:45 ` Mikko Perttunen
2019-07-29 9:45 ` Mikko Perttunen
2019-07-29 9:45 ` Mikko Perttunen
2019-07-25 13:20 ` Jon Hunter
2019-07-25 13:20 ` Jon Hunter
2019-07-25 13:20 ` Jon Hunter
2019-07-25 13:26 ` Jose Abreu
2019-07-25 13:26 ` Jose Abreu
2019-07-25 13:26 ` Jose Abreu
2019-07-25 14:25 ` Jon Hunter
2019-07-25 14:25 ` Jon Hunter
2019-07-25 15:12 ` Jose Abreu
2019-07-25 15:12 ` Jose Abreu
2019-07-26 14:11 ` Jon Hunter
2019-07-26 14:11 ` Jon Hunter
2019-07-27 15:56 ` Jose Abreu
2019-07-27 15:56 ` Jose Abreu
2019-07-29 8:16 ` Jose Abreu
2019-07-29 8:16 ` Jose Abreu
2019-07-29 10:55 ` Jon Hunter
2019-07-29 10:55 ` Jon Hunter
2019-07-29 11:29 ` Jose Abreu
2019-07-29 11:29 ` Jose Abreu
2019-07-29 11:52 ` Robin Murphy
2019-07-29 11:52 ` Robin Murphy
2019-07-29 14:08 ` Jose Abreu
2019-07-29 14:08 ` Jose Abreu
2019-07-29 21:33 ` Jon Hunter
2019-07-29 21:33 ` Jon Hunter
2019-07-30 9:39 ` Jose Abreu
2019-07-30 9:39 ` Jose Abreu
2019-07-30 13:36 ` Jon Hunter
2019-07-30 13:36 ` Jon Hunter
2019-07-30 13:58 ` Jose Abreu
2019-07-30 13:58 ` Jose Abreu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190704111109.GA12011@apalos \
--to=ilias.apalodimas@linaro.org \
--cc=Joao.Pinto@synopsys.com \
--cc=Jose.Abreu@synopsys.com \
--cc=alexandre.torgue@st.com \
--cc=brouer@redhat.com \
--cc=davem@davemloft.net \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-stm32@st-md-mailman.stormreply.com \
--cc=maxime.ripard@bootlin.com \
--cc=mcoquelin.stm32@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=peppe.cavallaro@st.com \
--cc=wens@csie.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.