From: Yunsheng Lin <linyunsheng@huawei.com>
To: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Cc: Matteo Croce <mcroce@linux.microsoft.com>,
<netdev@vger.kernel.org>, <linux-mm@kvack.org>,
Ayush Sawal <ayush.sawal@chelsio.com>,
"Vinay Kumar Yadav" <vinay.yadav@chelsio.com>,
Rohit Maheshwari <rohitm@chelsio.com>,
"David S. Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
Marcin Wojtas <mw@semihalf.com>,
Russell King <linux@armlinux.org.uk>,
Mirko Lindner <mlindner@marvell.com>,
Stephen Hemminger <stephen@networkplumber.org>,
"Tariq Toukan" <tariqt@nvidia.com>,
Jesper Dangaard Brouer <hawk@kernel.org>,
"Alexei Starovoitov" <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
"John Fastabend" <john.fastabend@gmail.com>,
Boris Pismenny <borisp@nvidia.com>, Arnd Bergmann <arnd@arndb.de>,
Andrew Morton <akpm@linux-foundation.org>,
"Peter Zijlstra (Intel)" <peterz@infradead.org>,
Vlastimil Babka <vbabka@suse.cz>, Yu Zhao <yuzhao@google.com>,
Will Deacon <will@kernel.org>, Fenghua Yu <fenghua.yu@intel.com>,
Roman Gushchin <guro@fb.com>, Hugh Dickins <hughd@google.com>,
Peter Xu <peterx@redhat.com>, Jason Gunthorpe <jgg@ziepe.ca>,
Jonathan Lemon <jonathan.lemon@gmail.com>,
Alexander Lobakin <alobakin@pm.me>,
Cong Wang <cong.wang@bytedance.com>, wenxu <wenxu@ucloud.cn>,
Kevin Hao <haokexin@gmail.com>,
Jakub Sitnicki <jakub@cloudflare.com>,
Marco Elver <elver@google.com>,
Willem de Bruijn <willemb@google.com>,
Miaohe Lin <linmiaohe@huawei.com>,
Guillaume Nault <gnault@redhat.com>,
<linux-kernel@vger.kernel.org>, <linux-rdma@vger.kernel.org>,
<bpf@vger.kernel.org>, Matthew Wilcox <willy@infradead.org>,
Eric Dumazet <edumazet@google.com>,
David Ahern <dsahern@gmail.com>,
Lorenzo Bianconi <lorenzo@kernel.org>,
Saeed Mahameed <saeedm@nvidia.com>, Andrew Lunn <andrew@lunn.ch>,
Paolo Abeni <pabeni@redhat.com>,
Sven Auhagen <sven.auhagen@voleatech.de>
Subject: Re: [PATCH net-next v5 3/5] page_pool: Allow drivers to hint on SKB recycling
Date: Fri, 14 May 2021 16:31:50 +0800 [thread overview]
Message-ID: <212498cf-376b-2dac-e1cd-12c7cc7910c6@huawei.com> (raw)
In-Reply-To: <YJ4ocslvURa/H+6f@apalos.home>
On 2021/5/14 15:36, Ilias Apalodimas wrote:
> [...]
>>> + return false;
>>> +
>>> + pp = (struct page_pool *)page->pp;
>>> +
>>> + /* Driver set this to memory recycling info. Reset it on recycle.
>>> + * This will *not* work for NIC using a split-page memory model.
>>> + * The page will be returned to the pool here regardless of the
>>> + * 'flipped' fragment being in use or not.
>>> + */
>>> + page->pp = NULL;
>>
>> Why not only clear the page->pp when the page can not be recycled
>> by the page pool? so that we do not need to set and clear it every
>> time the page is recycled。
>>
>
> If the page cannot be recycled, page->pp will not probably be set to begin
> with. Since we don't embed the feature in page_pool and we require the
> driver to explicitly enable it, as part of the 'skb flow', I'd rather keep
> it as is. When we set/clear the page->pp, the page is probably already in
> cache, so I doubt this will have any measurable impact.
The point is that we already have the skb->pp_recycle to let driver to
explicitly enable recycling, as part of the 'skb flow, if the page pool keep
the page->pp while it owns the page, then the driver may only need to call
one skb_mark_for_recycle() for a skb, instead of call skb_mark_for_recycle()
for each page frag of a skb.
Maybe we can add a parameter in "struct page_pool_params" to let driver
to decide if the page pool ptr is stored in page->pp while the page pool
owns the page?
Another thing accured to me is that if the driver use page from the
page pool to form a skb, and it does not call skb_mark_for_recycle(),
then there will be resource leaking, right? if yes, it seems the
skb_mark_for_recycle() call does not seems to add any value?
>
>>> + page_pool_put_full_page(pp, virt_to_head_page(data), false);
>>> +
>>> C(end);
>
> [...]
next prev parent reply other threads:[~2021-05-14 8:31 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-13 16:58 [PATCH net-next v5 0/5] page_pool: recycle buffers Matteo Croce
2021-05-13 16:58 ` [PATCH net-next v5 1/5] mm: add a signature in struct page Matteo Croce
2021-05-14 1:00 ` Matthew Wilcox
2021-05-14 1:34 ` Matteo Croce
2021-05-18 15:44 ` Matteo Croce
2021-05-13 16:58 ` [PATCH net-next v5 2/5] skbuff: add a parameter to __skb_frag_unref Matteo Croce
2021-05-13 16:58 ` [PATCH net-next v5 3/5] page_pool: Allow drivers to hint on SKB recycling Matteo Croce
2021-05-14 3:39 ` Yunsheng Lin
2021-05-14 7:36 ` Ilias Apalodimas
2021-05-14 8:31 ` Yunsheng Lin [this message]
2021-05-14 9:17 ` Ilias Apalodimas
2021-05-15 2:07 ` Yunsheng Lin
2021-05-17 6:38 ` Ilias Apalodimas
2021-05-17 8:25 ` Yunsheng Lin
2021-05-17 9:36 ` Ilias Apalodimas
2021-05-17 11:10 ` Yunsheng Lin
2021-05-17 11:35 ` Ilias Apalodimas
2021-05-13 16:58 ` [PATCH net-next v5 4/5] mvpp2: recycle buffers Matteo Croce
2021-05-13 18:20 ` Russell King (Oracle)
2021-05-13 23:52 ` Matteo Croce
2021-05-13 16:58 ` [PATCH net-next v5 5/5] mvneta: " Matteo Croce
2021-05-13 18:25 ` Russell King (Oracle)
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=212498cf-376b-2dac-e1cd-12c7cc7910c6@huawei.com \
--to=linyunsheng@huawei.com \
--cc=akpm@linux-foundation.org \
--cc=alobakin@pm.me \
--cc=andrew@lunn.ch \
--cc=arnd@arndb.de \
--cc=ast@kernel.org \
--cc=ayush.sawal@chelsio.com \
--cc=borisp@nvidia.com \
--cc=bpf@vger.kernel.org \
--cc=cong.wang@bytedance.com \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=dsahern@gmail.com \
--cc=edumazet@google.com \
--cc=elver@google.com \
--cc=fenghua.yu@intel.com \
--cc=gnault@redhat.com \
--cc=guro@fb.com \
--cc=haokexin@gmail.com \
--cc=hawk@kernel.org \
--cc=hughd@google.com \
--cc=ilias.apalodimas@linaro.org \
--cc=jakub@cloudflare.com \
--cc=jgg@ziepe.ca \
--cc=john.fastabend@gmail.com \
--cc=jonathan.lemon@gmail.com \
--cc=kuba@kernel.org \
--cc=linmiaohe@huawei.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-rdma@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=lorenzo@kernel.org \
--cc=mcroce@linux.microsoft.com \
--cc=mlindner@marvell.com \
--cc=mw@semihalf.com \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=peterx@redhat.com \
--cc=peterz@infradead.org \
--cc=rohitm@chelsio.com \
--cc=saeedm@nvidia.com \
--cc=stephen@networkplumber.org \
--cc=sven.auhagen@voleatech.de \
--cc=tariqt@nvidia.com \
--cc=thomas.petazzoni@bootlin.com \
--cc=vbabka@suse.cz \
--cc=vinay.yadav@chelsio.com \
--cc=wenxu@ucloud.cn \
--cc=will@kernel.org \
--cc=willemb@google.com \
--cc=willy@infradead.org \
--cc=yuzhao@google.com \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).