RE: [PATCH net-next v2 17/17] net: Kill MSG_SENDPAGE_NOTLAST

From: Willem de Bruijn
Date: Sun Jun 18 2023 - 12:54:48 EST


David Howells wrote:
> Now that ->sendpage() has been removed, MSG_SENDPAGE_NOTLAST can be cleaned
> up. Things were converted to use MSG_MORE instead, but the protocol
> sendpage stubs still convert MSG_SENDPAGE_NOTLAST to MSG_MORE, which is now
> unnecessary.
>
> Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
> cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> cc: Eric Dumazet <edumazet@xxxxxxxxxx>
> cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> cc: Paolo Abeni <pabeni@xxxxxxxxxx>
> cc: Jens Axboe <axboe@xxxxxxxxx>
> cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
> cc: bpf@xxxxxxxxxxxxxxx
> cc: dccp@xxxxxxxxxxxxxxx
> cc: linux-afs@xxxxxxxxxxxxxxxxxxx
> cc: linux-arm-msm@xxxxxxxxxxxxxxx
> cc: linux-can@xxxxxxxxxxxxxxx
> cc: linux-crypto@xxxxxxxxxxxxxxx
> cc: linux-doc@xxxxxxxxxxxxxxx
> cc: linux-hams@xxxxxxxxxxxxxxx
> cc: linux-perf-users@xxxxxxxxxxxxxxx
> cc: linux-rdma@xxxxxxxxxxxxxxx
> cc: linux-sctp@xxxxxxxxxxxxxxx
> cc: linux-wpan@xxxxxxxxxxxxxxx
> cc: linux-x25@xxxxxxxxxxxxxxx
> cc: mptcp@xxxxxxxxxxxxxxx
> cc: netdev@xxxxxxxxxxxxxxx
> cc: rds-devel@xxxxxxxxxxxxxx
> cc: tipc-discussion@xxxxxxxxxxxxxxxxxxxxx
> cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
> ---
> include/linux/socket.h | 4 +---
> net/ipv4/tcp_bpf.c | 4 +++-
> net/tls/tls_device.c | 3 +--
> net/tls/tls_main.c | 2 +-
> net/tls/tls_sw.c | 2 +-
> tools/perf/trace/beauty/include/linux/socket.h | 1 -
> tools/perf/trace/beauty/msg_flags.c | 3 ---
> 7 files changed, 7 insertions(+), 12 deletions(-)
>

> @@ -90,7 +90,9 @@ static int tcp_bpf_push(struct sock *sk, struct sk_msg *msg, u32 apply_bytes,
> {
> bool apply = apply_bytes;
> struct scatterlist *sge;
> - struct msghdr msghdr = { .msg_flags = flags | MSG_SPLICE_PAGES, };
> + struct msghdr msghdr = {
> + .msg_flags = flags | MSG_SPLICE_PAGES | MSG_MORE,
> + };
> struct page *page;
> int size, ret = 0;
> u32 off;

Is it intentional to add MSG_MORE here in this patch?

I do see that patch 3 removes this branch:

@@ -111,9 +111,6 @@ static int tcp_bpf_push(struct sock *sk, struct sk_msg *msg, u32 apply_bytes,
if (has_tx_ulp)
msghdr.msg_flags |= MSG_SENDPAGE_NOPOLICY;

- if (flags & MSG_SENDPAGE_NOTLAST)
- msghdr.msg_flags |= MSG_MORE;
-