linux-alpha.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Pavel Begunkov <asml.silence@gmail.com>
To: Mina Almasry <almasrymina@google.com>
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-doc@vger.kernel.org, linux-alpha@vger.kernel.org,
	linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org,
	sparclinux@vger.kernel.org, linux-renesas-soc@vger.kernel.org,
	linux-trace-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
	bpf@vger.kernel.org, linux-kselftest@vger.kernel.org,
	linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org,
	"David S. Miller" <davem@davemloft.net>,
	"Eric Dumazet" <edumazet@google.com>,
	"Jakub Kicinski" <kuba@kernel.org>,
	"Paolo Abeni" <pabeni@redhat.com>,
	"Donald Hunter" <donald.hunter@gmail.com>,
	"Jonathan Corbet" <corbet@lwn.net>,
	"Richard Henderson" <richard.henderson@linaro.org>,
	"Ivan Kokshaysky" <ink@jurassic.park.msu.ru>,
	"Matt Turner" <mattst88@gmail.com>,
	"Thomas Bogendoerfer" <tsbogend@alpha.franken.de>,
	"James E.J. Bottomley" <James.Bottomley@hansenpartnership.com>,
	"Helge Deller" <deller@gmx.de>,
	"Andreas Larsson" <andreas@gaisler.com>,
	"Sergey Shtylyov" <s.shtylyov@omp.ru>,
	"Jesper Dangaard Brouer" <hawk@kernel.org>,
	"Ilias Apalodimas" <ilias.apalodimas@linaro.org>,
	"Steven Rostedt" <rostedt@goodmis.org>,
	"Masami Hiramatsu" <mhiramat@kernel.org>,
	"Mathieu Desnoyers" <mathieu.desnoyers@efficios.com>,
	"Arnd Bergmann" <arnd@arndb.de>,
	"Alexei Starovoitov" <ast@kernel.org>,
	"Daniel Borkmann" <daniel@iogearbox.net>,
	"Andrii Nakryiko" <andrii@kernel.org>,
	"Martin KaFai Lau" <martin.lau@linux.dev>,
	"Eduard Zingerman" <eddyz87@gmail.com>,
	"Song Liu" <song@kernel.org>,
	"Yonghong Song" <yonghong.song@linux.dev>,
	"John Fastabend" <john.fastabend@gmail.com>,
	"KP Singh" <kpsingh@kernel.org>,
	"Stanislav Fomichev" <sdf@google.com>,
	"Hao Luo" <haoluo@google.com>, "Jiri Olsa" <jolsa@kernel.org>,
	"Steffen Klassert" <steffen.klassert@secunet.com>,
	"Herbert Xu" <herbert@gondor.apana.org.au>,
	"David Ahern" <dsahern@kernel.org>,
	"Willem de Bruijn" <willemdebruijn.kernel@gmail.com>,
	"Shuah Khan" <shuah@kernel.org>,
	"Sumit Semwal" <sumit.semwal@linaro.org>,
	"Christian König" <christian.koenig@amd.com>,
	"Bagas Sanjaya" <bagasdotme@gmail.com>,
	"Christoph Hellwig" <hch@infradead.org>,
	"Nikolay Aleksandrov" <razor@blackwall.org>,
	"David Wei" <dw@davidwei.uk>, "Jason Gunthorpe" <jgg@ziepe.ca>,
	"Yunsheng Lin" <linyunsheng@huawei.com>,
	"Shailend Chand" <shailend@google.com>,
	"Harshitha Ramamurthy" <hramamurthy@google.com>,
	"Shakeel Butt" <shakeel.butt@linux.dev>,
	"Jeroen de Borst" <jeroendb@google.com>,
	"Praveen Kaligineedi" <pkaligineedi@google.com>,
	linux-mm@kvack.org, "Matthew Wilcox" <willy@infradead.org>
Subject: Re: [PATCH net-next v12 06/13] page_pool: devmem support
Date: Mon, 24 Jun 2024 01:12:46 +0100	[thread overview]
Message-ID: <c9333388-6906-4df9-92b4-ecfd324f5891@gmail.com> (raw)
In-Reply-To: <CAHS8izNr4x6SW0oY_VJDPZOsrBQEAyJO1qVJQbu8VNJQMtX9Sg@mail.gmail.com>

On 6/21/24 19:48, Mina Almasry wrote:
> On Mon, Jun 17, 2024 at 7:17 AM Pavel Begunkov <asml.silence@gmail.com> wrote:
...
>>>    static inline unsigned long netmem_to_pfn(netmem_ref netmem)
>>>    {
>>> +     if (netmem_is_net_iov(netmem))
>>> +             return 0;
>>
>> IIRC 0 is a valid pfn. Not much of a concern since it's
>> used only for tracing, but might make sense to pass some
>> invalid pfn if there is one
>>
> 
> AFAIU all non-negative pfns are technically valid pfns if the machine
> is big enough.
> 
> I could have this function return long long instead of unsigned long
> so I can return a negative number for errors, and then cast to
> unsigned long when I figure out it's actually a pfn. Seemed like such
> a hassle especially since the call site is just tracing that I figured
> it's not that worth it.

Yeah, sounds like an overkill for tracing

> 
>>> +
>>>        return page_to_pfn(netmem_to_page(netmem));
>>>    }
>>>
>> ...
>>>    static inline netmem_ref netmem_compound_head(netmem_ref netmem)
>>>    {
>>> +     /* niov are never compounded */
>>> +     if (netmem_is_net_iov(netmem))
>>> +             return netmem;
>>> +
>>>        return page_to_netmem(compound_head(netmem_to_page(netmem)));
>>>    }
>>>
>>> +static inline void *netmem_address(netmem_ref netmem)
>>
>> I don't think it's used anywhere, do I miss it?
>>
> 
> Ah, It's used by the GVE devmem implementation:
> https://github.com/mina/linux/commit/da89baa81873d457cbf7b49ee6b4f0d66855b205
> 
> I could leave it out of this patch, then add it with the follow up GVE
> devmem implementation, but I figured almost for sure drivers are going
> to need this eventually, and it's small, so just put it here.

Either way is fine by me, checking the function is not leftovers


-- 
Pavel Begunkov

  reply	other threads:[~2024-06-24  0:12 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-06-13  1:35 [PATCH net-next v12 00/13] Device Memory TCP Mina Almasry
2024-06-13  1:35 ` [PATCH net-next v12 01/13] netdev: add netdev_rx_queue_restart() Mina Almasry
2024-06-17 13:20   ` Pavel Begunkov
2024-06-13  1:35 ` [PATCH net-next v12 02/13] net: netdev netlink api to bind dma-buf to a net device Mina Almasry
2024-06-13  1:35 ` [PATCH net-next v12 03/13] netdev: support binding dma-buf to netdevice Mina Almasry
2024-06-14  8:36   ` Markus Elfring
2024-06-17 13:22   ` Pavel Begunkov
2024-06-13  1:35 ` [PATCH net-next v12 04/13] netdev: netdevice devmem allocator Mina Almasry
2024-06-17 13:42   ` Pavel Begunkov
2024-06-13  1:35 ` [PATCH net-next v12 05/13] page_pool: convert to use netmem Mina Almasry
2024-06-13  8:36   ` Paul Barker
2024-06-13 14:18     ` Mina Almasry
2024-06-17 17:52   ` Pavel Begunkov
2024-06-13  1:35 ` [PATCH net-next v12 06/13] page_pool: devmem support Mina Almasry
2024-06-17 14:16   ` Pavel Begunkov
2024-06-21 18:48     ` Mina Almasry
2024-06-24  0:12       ` Pavel Begunkov [this message]
2024-06-13  1:35 ` [PATCH net-next v12 07/13] memory-provider: dmabuf devmem memory provider Mina Almasry
2024-06-17 14:45   ` Pavel Begunkov
2024-06-13  1:35 ` [PATCH net-next v12 08/13] net: support non paged skb frags Mina Almasry
2024-06-13  1:35 ` [PATCH net-next v12 09/13] net: add support for skbs with unreadable frags Mina Almasry
2024-06-13  1:35 ` [PATCH net-next v12 10/13] tcp: RX path for devmem TCP Mina Almasry
2024-06-17 16:36   ` Pavel Begunkov
2024-06-21 20:31     ` Mina Almasry
2024-06-24  0:13       ` Pavel Begunkov
2024-06-13  1:35 ` [PATCH net-next v12 11/13] net: add SO_DEVMEM_DONTNEED setsockopt to release RX frags Mina Almasry
2024-06-13  1:35 ` [PATCH net-next v12 12/13] net: add devmem TCP documentation Mina Almasry
2024-06-13  1:35 ` [PATCH net-next v12 13/13] selftests: add ncdevmem, netcat for devmem TCP Mina Almasry
2024-06-14  1:34 ` [PATCH net-next v12 00/13] Device Memory TCP Jakub Kicinski
2024-06-14  4:40   ` Mina Almasry

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=c9333388-6906-4df9-92b4-ecfd324f5891@gmail.com \
    --to=asml.silence@gmail.com \
    --cc=James.Bottomley@hansenpartnership.com \
    --cc=almasrymina@google.com \
    --cc=andreas@gaisler.com \
    --cc=andrii@kernel.org \
    --cc=arnd@arndb.de \
    --cc=ast@kernel.org \
    --cc=bagasdotme@gmail.com \
    --cc=bpf@vger.kernel.org \
    --cc=christian.koenig@amd.com \
    --cc=corbet@lwn.net \
    --cc=daniel@iogearbox.net \
    --cc=davem@davemloft.net \
    --cc=deller@gmx.de \
    --cc=donald.hunter@gmail.com \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=dsahern@kernel.org \
    --cc=dw@davidwei.uk \
    --cc=eddyz87@gmail.com \
    --cc=edumazet@google.com \
    --cc=haoluo@google.com \
    --cc=hawk@kernel.org \
    --cc=hch@infradead.org \
    --cc=herbert@gondor.apana.org.au \
    --cc=hramamurthy@google.com \
    --cc=ilias.apalodimas@linaro.org \
    --cc=ink@jurassic.park.msu.ru \
    --cc=jeroendb@google.com \
    --cc=jgg@ziepe.ca \
    --cc=john.fastabend@gmail.com \
    --cc=jolsa@kernel.org \
    --cc=kpsingh@kernel.org \
    --cc=kuba@kernel.org \
    --cc=linux-alpha@vger.kernel.org \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-kselftest@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=linux-mips@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-parisc@vger.kernel.org \
    --cc=linux-renesas-soc@vger.kernel.org \
    --cc=linux-trace-kernel@vger.kernel.org \
    --cc=linyunsheng@huawei.com \
    --cc=martin.lau@linux.dev \
    --cc=mathieu.desnoyers@efficios.com \
    --cc=mattst88@gmail.com \
    --cc=mhiramat@kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    --cc=pkaligineedi@google.com \
    --cc=razor@blackwall.org \
    --cc=richard.henderson@linaro.org \
    --cc=rostedt@goodmis.org \
    --cc=s.shtylyov@omp.ru \
    --cc=sdf@google.com \
    --cc=shailend@google.com \
    --cc=shakeel.butt@linux.dev \
    --cc=shuah@kernel.org \
    --cc=song@kernel.org \
    --cc=sparclinux@vger.kernel.org \
    --cc=steffen.klassert@secunet.com \
    --cc=sumit.semwal@linaro.org \
    --cc=tsbogend@alpha.franken.de \
    --cc=willemdebruijn.kernel@gmail.com \
    --cc=willy@infradead.org \
    --cc=yonghong.song@linux.dev \
    /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 read-only IMAP folder(s) and NNTP newsgroup(s).