| Message ID | 20230329141354.516864-38-dhowells@redhat.com (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Headers | show |
| Series | splice, net: Replace sendpage with sendmsg(MSG_SPLICE_PAGES) | expand |
David, BTW, will this two patch depend on the others in this patch series ? I am planing to run a test with these two later. Thanks - Xiubo On 29/03/2023 22:13, David Howells wrote: > Use sendmsg() and MSG_SPLICE_PAGES rather than sendpage in ceph when > transmitting data. For the moment, this can only transmit one page at a > time because of the architecture of net/ceph/, but if > write_partial_message_data() can be given a bvec[] at a time by the > iteration code, this would allow pages to be sent in a batch. > > Signed-off-by: David Howells <dhowells@redhat.com> > cc: Ilya Dryomov <idryomov@gmail.com> > cc: Xiubo Li <xiubli@redhat.com> > cc: Jeff Layton <jlayton@kernel.org> > cc: "David S. Miller" <davem@davemloft.net> > cc: Eric Dumazet <edumazet@google.com> > cc: Jakub Kicinski <kuba@kernel.org> > cc: Paolo Abeni <pabeni@redhat.com> > cc: Jens Axboe <axboe@kernel.dk> > cc: Matthew Wilcox <willy@infradead.org> > cc: ceph-devel@vger.kernel.org > cc: netdev@vger.kernel.org > --- > net/ceph/messenger_v2.c | 89 +++++++++-------------------------------- > 1 file changed, 18 insertions(+), 71 deletions(-) > > diff --git a/net/ceph/messenger_v2.c b/net/ceph/messenger_v2.c > index 301a991dc6a6..1637a0c21126 100644 > --- a/net/ceph/messenger_v2.c > +++ b/net/ceph/messenger_v2.c > @@ -117,91 +117,38 @@ static int ceph_tcp_recv(struct ceph_connection *con) > return ret; > } > > -static int do_sendmsg(struct socket *sock, struct iov_iter *it) > -{ > - struct msghdr msg = { .msg_flags = CEPH_MSG_FLAGS }; > - int ret; > - > - msg.msg_iter = *it; > - while (iov_iter_count(it)) { > - ret = sock_sendmsg(sock, &msg); > - if (ret <= 0) { > - if (ret == -EAGAIN) > - ret = 0; > - return ret; > - } > - > - iov_iter_advance(it, ret); > - } > - > - WARN_ON(msg_data_left(&msg)); > - return 1; > -} > - > -static int do_try_sendpage(struct socket *sock, struct iov_iter *it) > -{ > - struct msghdr msg = { .msg_flags = CEPH_MSG_FLAGS }; > - struct bio_vec bv; > - int ret; > - > - if (WARN_ON(!iov_iter_is_bvec(it))) > - return -EINVAL; > - > - while (iov_iter_count(it)) { > - /* iov_iter_iovec() for ITER_BVEC */ > - bvec_set_page(&bv, it->bvec->bv_page, > - min(iov_iter_count(it), > - it->bvec->bv_len - it->iov_offset), > - it->bvec->bv_offset + it->iov_offset); > - > - /* > - * sendpage cannot properly handle pages with > - * page_count == 0, we need to fall back to sendmsg if > - * that's the case. > - * > - * Same goes for slab pages: skb_can_coalesce() allows > - * coalescing neighboring slab objects into a single frag > - * which triggers one of hardened usercopy checks. > - */ > - if (sendpage_ok(bv.bv_page)) { > - ret = sock->ops->sendpage(sock, bv.bv_page, > - bv.bv_offset, bv.bv_len, > - CEPH_MSG_FLAGS); > - } else { > - iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bv, 1, bv.bv_len); > - ret = sock_sendmsg(sock, &msg); > - } > - if (ret <= 0) { > - if (ret == -EAGAIN) > - ret = 0; > - return ret; > - } > - > - iov_iter_advance(it, ret); > - } > - > - return 1; > -} > - > /* > * Write as much as possible. The socket is expected to be corked, > * so we don't bother with MSG_MORE/MSG_SENDPAGE_NOTLAST here. > * > * Return: > - * 1 - done, nothing (else) to write > + * >0 - done, nothing (else) to write > * 0 - socket is full, need to wait > * <0 - error > */ > static int ceph_tcp_send(struct ceph_connection *con) > { > + struct msghdr msg = { > + .msg_iter = con->v2.out_iter, > + .msg_flags = CEPH_MSG_FLAGS, > + }; > int ret; > > + if (WARN_ON(!iov_iter_is_bvec(&con->v2.out_iter))) > + return -EINVAL; > + > + if (con->v2.out_iter_sendpage) > + msg.msg_flags |= MSG_SPLICE_PAGES; > + > dout("%s con %p have %zu try_sendpage %d\n", __func__, con, > iov_iter_count(&con->v2.out_iter), con->v2.out_iter_sendpage); > - if (con->v2.out_iter_sendpage) > - ret = do_try_sendpage(con->sock, &con->v2.out_iter); > - else > - ret = do_sendmsg(con->sock, &con->v2.out_iter); > + > + ret = sock_sendmsg(con->sock, &msg); > + if (ret > 0) > + iov_iter_advance(&con->v2.out_iter, ret); > + else if (ret == -EAGAIN) > + ret = 0; > + > dout("%s con %p ret %d left %zu\n", __func__, con, ret, > iov_iter_count(&con->v2.out_iter)); > return ret; >
Xiubo Li <xiubli@redhat.com> wrote:
> BTW, will this two patch depend on the others in this patch series ?
Yes. You'll need patches that affect TCP at least so that TCP supports
MSG_SPLICE_PAGES, so 04-08 and perhaps 09. It's also on top of the patches
that remove ITER_PIPE on my iov-extract branch, but I don't think that should
affect you.
David
On 3/30/23 02:48, David Howells wrote: > Xiubo Li <xiubli@redhat.com> wrote: > >> BTW, will this two patch depend on the others in this patch series ? > Yes. You'll need patches that affect TCP at least so that TCP supports > MSG_SPLICE_PAGES, so 04-08 and perhaps 09. It's also on top of the patches > that remove ITER_PIPE on my iov-extract branch, but I don't think that should > affect you. Okay, I will check that. Thanks. > David >
On 3/30/23 14:48, David Howells wrote: > Xiubo Li <xiubli@redhat.com> wrote: > >> BTW, will this two patch depend on the others in this patch series ? > Yes. You'll need patches that affect TCP at least so that TCP supports > MSG_SPLICE_PAGES, so 04-08 and perhaps 09. It's also on top of the patches > that remove ITER_PIPE on my iov-extract branch, but I don't think that should > affect you. Why I asked this is because I only could see these two ceph relevant patches currently. Thanks - Xiubo > David >
Xiubo Li <xiubli@redhat.com> wrote: > On 3/30/23 14:48, David Howells wrote: > > Xiubo Li <xiubli@redhat.com> wrote: > > > >> BTW, will this two patch depend on the others in this patch series ? > > Yes. You'll need patches that affect TCP at least so that TCP supports > > MSG_SPLICE_PAGES, so 04-08 and perhaps 09. It's also on top of the > > patches that remove ITER_PIPE on my iov-extract branch, but I don't think > > that should affect you. > > Why I asked this is because I only could see these two ceph relevant patches > currently. Depends on how you defined 'relevant', I guess. Only two patches modify ceph directly, but there's a dependency: to make those work, TCP needs altering also. David
On 4/3/23 16:32, David Howells wrote: > Xiubo Li <xiubli@redhat.com> wrote: > >> On 3/30/23 14:48, David Howells wrote: >>> Xiubo Li <xiubli@redhat.com> wrote: >>> >>>> BTW, will this two patch depend on the others in this patch series ? >>> Yes. You'll need patches that affect TCP at least so that TCP supports >>> MSG_SPLICE_PAGES, so 04-08 and perhaps 09. It's also on top of the >>> patches that remove ITER_PIPE on my iov-extract branch, but I don't think >>> that should affect you. >> Why I asked this is because I only could see these two ceph relevant patches >> currently. > Depends on how you defined 'relevant', I guess. Only two patches modify ceph > directly, but there's a dependency: to make those work, TCP needs altering > also. Okay. Will run the test today. I was reinstalling my laptop last week. Thanks - Xiubo > David >
diff --git a/net/ceph/messenger_v2.c b/net/ceph/messenger_v2.c index 301a991dc6a6..1637a0c21126 100644 --- a/net/ceph/messenger_v2.c +++ b/net/ceph/messenger_v2.c @@ -117,91 +117,38 @@ static int ceph_tcp_recv(struct ceph_connection *con) return ret; } -static int do_sendmsg(struct socket *sock, struct iov_iter *it) -{ - struct msghdr msg = { .msg_flags = CEPH_MSG_FLAGS }; - int ret; - - msg.msg_iter = *it; - while (iov_iter_count(it)) { - ret = sock_sendmsg(sock, &msg); - if (ret <= 0) { - if (ret == -EAGAIN) - ret = 0; - return ret; - } - - iov_iter_advance(it, ret); - } - - WARN_ON(msg_data_left(&msg)); - return 1; -} - -static int do_try_sendpage(struct socket *sock, struct iov_iter *it) -{ - struct msghdr msg = { .msg_flags = CEPH_MSG_FLAGS }; - struct bio_vec bv; - int ret; - - if (WARN_ON(!iov_iter_is_bvec(it))) - return -EINVAL; - - while (iov_iter_count(it)) { - /* iov_iter_iovec() for ITER_BVEC */ - bvec_set_page(&bv, it->bvec->bv_page, - min(iov_iter_count(it), - it->bvec->bv_len - it->iov_offset), - it->bvec->bv_offset + it->iov_offset); - - /* - * sendpage cannot properly handle pages with - * page_count == 0, we need to fall back to sendmsg if - * that's the case. - * - * Same goes for slab pages: skb_can_coalesce() allows - * coalescing neighboring slab objects into a single frag - * which triggers one of hardened usercopy checks. - */ - if (sendpage_ok(bv.bv_page)) { - ret = sock->ops->sendpage(sock, bv.bv_page, - bv.bv_offset, bv.bv_len, - CEPH_MSG_FLAGS); - } else { - iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bv, 1, bv.bv_len); - ret = sock_sendmsg(sock, &msg); - } - if (ret <= 0) { - if (ret == -EAGAIN) - ret = 0; - return ret; - } - - iov_iter_advance(it, ret); - } - - return 1; -} - /* * Write as much as possible. The socket is expected to be corked, * so we don't bother with MSG_MORE/MSG_SENDPAGE_NOTLAST here. * * Return: - * 1 - done, nothing (else) to write + * >0 - done, nothing (else) to write * 0 - socket is full, need to wait * <0 - error */ static int ceph_tcp_send(struct ceph_connection *con) { + struct msghdr msg = { + .msg_iter = con->v2.out_iter, + .msg_flags = CEPH_MSG_FLAGS, + }; int ret; + if (WARN_ON(!iov_iter_is_bvec(&con->v2.out_iter))) + return -EINVAL; + + if (con->v2.out_iter_sendpage) + msg.msg_flags |= MSG_SPLICE_PAGES; + dout("%s con %p have %zu try_sendpage %d\n", __func__, con, iov_iter_count(&con->v2.out_iter), con->v2.out_iter_sendpage); - if (con->v2.out_iter_sendpage) - ret = do_try_sendpage(con->sock, &con->v2.out_iter); - else - ret = do_sendmsg(con->sock, &con->v2.out_iter); + + ret = sock_sendmsg(con->sock, &msg); + if (ret > 0) + iov_iter_advance(&con->v2.out_iter, ret); + else if (ret == -EAGAIN) + ret = 0; + dout("%s con %p ret %d left %zu\n", __func__, con, ret, iov_iter_count(&con->v2.out_iter)); return ret;
Use sendmsg() and MSG_SPLICE_PAGES rather than sendpage in ceph when transmitting data. For the moment, this can only transmit one page at a time because of the architecture of net/ceph/, but if write_partial_message_data() can be given a bvec[] at a time by the iteration code, this would allow pages to be sent in a batch. Signed-off-by: David Howells <dhowells@redhat.com> cc: Ilya Dryomov <idryomov@gmail.com> cc: Xiubo Li <xiubli@redhat.com> cc: Jeff Layton <jlayton@kernel.org> cc: "David S. Miller" <davem@davemloft.net> cc: Eric Dumazet <edumazet@google.com> cc: Jakub Kicinski <kuba@kernel.org> cc: Paolo Abeni <pabeni@redhat.com> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> cc: ceph-devel@vger.kernel.org cc: netdev@vger.kernel.org --- net/ceph/messenger_v2.c | 89 +++++++++-------------------------------- 1 file changed, 18 insertions(+), 71 deletions(-)