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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: wp7h3659pkugw5gaa8ey1u5yzsqkk77r X-Rspamd-Queue-Id: 090D28000D X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1746799716-395548 X-HE-Meta: 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 UUkC5GEi RCqUnMaIDiD1tkNE= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: j On Fri, May 9, 2025 at 6:39=E2=80=AFAM Mina Almasry wrote: > > On Fri, May 9, 2025 at 4:51=E2=80=AFAM Byungchul Park = wrote: > > > > To eliminate the use of struct page in page pool, the page pool code > > should use netmem descriptor and API instead. > > > > As part of the work, introduce netmem alloc/put API allowing the code t= o > > use them rather than struct page things. > > > > Signed-off-by: Byungchul Park > > --- > > include/net/netmem.h | 18 ++++++++++++++++++ > > 1 file changed, 18 insertions(+) > > > > diff --git a/include/net/netmem.h b/include/net/netmem.h > > index 45c209d6cc689..c87a604e980b9 100644 > > --- a/include/net/netmem.h > > +++ b/include/net/netmem.h > > @@ -138,6 +138,24 @@ static inline netmem_ref page_to_netmem(struct pag= e *page) > > return (__force netmem_ref)page; > > } > > > > +static inline netmem_ref alloc_netmems_node(int nid, gfp_t gfp_mask, > > + unsigned int order) > > +{ > > + return page_to_netmem(alloc_pages_node(nid, gfp_mask, order)); > > +} > > + > > +static inline unsigned long alloc_netmems_bulk_node(gfp_t gfp, int nid= , > > + unsigned long nr_netmems, netmem_ref *netmem_array) > > +{ > > + return alloc_pages_bulk_node(gfp, nid, nr_netmems, > > + (struct page **)netmem_array); > > +} > > + > > +static inline void put_netmem(netmem_ref netmem) > > +{ > > + put_page(netmem_to_page(netmem)); > > +} > > We can't really do this. netmem_ref is an abstraction that can be a > struct page or struct net_iov underneath. We can't be sure when > put_netmem is called that it is safe to convert to a page via > netmem_to_page(). This will crash if put_netmem is called on a > netmem_ref that is a net_iov underneath. > On a closer look, it looks like this put_netmem is only called from code paths where you are sure the netmem_ref is a page underneath, so this is likely fine for now. There is a net_next series that is adding proper put_netmem support [1]. It's probably best to rebase your work on top of that, but this should be fine in the meantime. [1] https://lore.kernel.org/netdev/20250508004830.4100853-1-almasrymina@goo= gle.com/ -- Thanks, Mina