Re: [PATCH v1 05/15] net: prepare for non devmem TCP memory providers

Pavel Begunkov
2024-10-09T21:45:06Z

On 10/9/24 21:56, Mina Almasry wrote:
> On Mon, Oct 7, 2024 at 3:16 PM David Wei <dw@davidwei.uk> wrote:
>>
>> From: Pavel Begunkov <asml.silence@gmail.com>
>>
>> There is a good bunch of places in generic paths assuming that the only
>> page pool memory provider is devmem TCP. As we want to reuse the net_iov
>> and provider infrastructure, we need to patch it up and explicitly check
>> the provider type when we branch into devmem TCP code.
>>
>> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
>> Signed-off-by: David Wei <dw@davidwei.uk>
>> ---
>> net/core/devmem.c | 4 ++--
>> net/core/page_pool_user.c | 15 +++++++++------
>> net/ipv4/tcp.c | 6 ++++++
>> 3 files changed, 17 insertions(+), 8 deletions(-)
>>
>> diff --git a/net/core/devmem.c b/net/core/devmem.c
>> index 83d13eb441b6..b0733cf42505 100644
>> --- a/net/core/devmem.c
>> +++ b/net/core/devmem.c
>> @@ -314,10 +314,10 @@ void dev_dmabuf_uninstall(struct net_device *dev)
>> unsigned int i;
>>
>> for (i = 0; i < dev->real_num_rx_queues; i++) {
>> - binding = dev->_rx[i].mp_params.mp_priv;
>> - if (!binding)
>> + if (dev->_rx[i].mp_params.mp_ops != &dmabuf_devmem_ops)
>> continue;
>>
>
> Sorry if I missed it (and please ignore me if I did), but
> dmabuf_devmem_ops are maybe not defined yet?

You exported it in devmem.h

> I'm also wondering how to find all the annyoing places where we need
> to check this. Looks like maybe a grep for net_devmem_dmabuf_binding
> is the way to go? I need to check whether these are all the places we
> need the check but so far looks fine.

I whac-a-mole'd them the best I can following recent devmem TCP
changes. Would be great if you take a look and might remember
some more places to check. And thanks for the review!

--
Pavel Begunkov