| Message ID | 20220130180256.28303-4-tonylu@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net/smc: Improvements for TCP_CORK and sendfile() | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Clearly marked for net-next |
| netdev/fixes_present | success | Fixes tag not required for -next series |
| netdev/subject_prefix | success | Link |
| netdev/cover_letter | success | Series has a cover letter |
| netdev/patch_count | success | Link |
| netdev/header_inline | success | No static functions without inline keyword in header files |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/cc_maintainers | success | CCed 5 of 5 maintainers |
| netdev/build_clang | success | Errors and warnings before: 0 this patch: 0 |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Signed-off-by tag matches author and committer |
| netdev/verify_fixes | success | No Fixes tag |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 50 lines checked |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/source_inline | success | Was 0 now: 0 |
On 1/30/22 19:02, Tony Lu wrote: > This introduces a new corked flag, MSG_SENDPAGE_NOTLAST, which is > involved in syscall sendfile() [1], it indicates this is not the last > page. So we can cork the data until the page is not specify this flag. > It has the same effect as MSG_MORE, but existed in sendfile() only. > > This patch adds a option MSG_SENDPAGE_NOTLAST for corking data, try to > cork more data before sending when using sendfile(), which acts like > TCP's behaviour. Also, this reimplements the default sendpage to inform > that it is supported to some extent. > > [1] https://man7.org/linux/man-pages/man2/sendfile.2.html > > Signed-off-by: Tony Lu <tonylu@linux.alibaba.com> > --- > net/smc/af_smc.c | 4 +++- > net/smc/smc_tx.c | 19 ++++++++++++++++++- > net/smc/smc_tx.h | 2 ++ > 3 files changed, 23 insertions(+), 2 deletions(-) > > diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c > index ef021ec6b361..8b78010afe01 100644 > --- a/net/smc/af_smc.c > +++ b/net/smc/af_smc.c > @@ -2729,8 +2729,10 @@ static ssize_t smc_sendpage(struct socket *sock, struct page *page, > rc = kernel_sendpage(smc->clcsock, page, offset, > size, flags); > } else { > + lock_sock(sk); > + rc = smc_tx_sendpage(smc, page, offset, size, flags); > + release_sock(sk); > SMC_STAT_INC(smc, sendpage_cnt); > - rc = sock_no_sendpage(sock, page, offset, size, flags); > } > > out: > diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c > index 9cec62cae7cb..a96ce162825e 100644 > --- a/net/smc/smc_tx.c > +++ b/net/smc/smc_tx.c > @@ -235,7 +235,8 @@ int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len) > */ > if ((msg->msg_flags & MSG_OOB) && !send_remaining) > conn->urg_tx_pend = true; > - if ((msg->msg_flags & MSG_MORE || smc_tx_is_corked(smc)) && > + if ((msg->msg_flags & MSG_MORE || smc_tx_is_corked(smc) || > + msg->msg_flags & MSG_SENDPAGE_NOTLAST) && > (atomic_read(&conn->sndbuf_space))) > /* for a corked socket defer the RDMA writes if > * sndbuf_space is still available. The applications > @@ -257,6 +258,22 @@ int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len) > return rc; > } > > +int smc_tx_sendpage(struct smc_sock *smc, struct page *page, int offset, > + size_t size, int flags) > +{ > + struct msghdr msg = {.msg_flags = flags}; > + char *kaddr = kmap(page); > + struct kvec iov; > + int rc; > + > + iov.iov_base = kaddr + offset; > + iov.iov_len = size; > + iov_iter_kvec(&msg.msg_iter, WRITE, &iov, 1, size); > + rc = smc_tx_sendmsg(smc, &msg, size); > + kunmap(page); > + return rc; > +} > + > /***************************** sndbuf consumer *******************************/ > > /* sndbuf consumer: actual data transfer of one target chunk with ISM write */ > diff --git a/net/smc/smc_tx.h b/net/smc/smc_tx.h > index a59f370b8b43..34b578498b1f 100644 > --- a/net/smc/smc_tx.h > +++ b/net/smc/smc_tx.h > @@ -31,6 +31,8 @@ void smc_tx_pending(struct smc_connection *conn); > void smc_tx_work(struct work_struct *work); > void smc_tx_init(struct smc_sock *smc); > int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len); > +int smc_tx_sendpage(struct smc_sock *smc, struct page *page, int offset, > + size_t size, int flags); > int smc_tx_sndbuf_nonempty(struct smc_connection *conn); > void smc_tx_sndbuf_nonfull(struct smc_sock *smc); > void smc_tx_consumer_update(struct smc_connection *conn, bool force); > Reviewed-by: Stefan Raspl <raspl@linux.ibm.com>
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index ef021ec6b361..8b78010afe01 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -2729,8 +2729,10 @@ static ssize_t smc_sendpage(struct socket *sock, struct page *page, rc = kernel_sendpage(smc->clcsock, page, offset, size, flags); } else { + lock_sock(sk); + rc = smc_tx_sendpage(smc, page, offset, size, flags); + release_sock(sk); SMC_STAT_INC(smc, sendpage_cnt); - rc = sock_no_sendpage(sock, page, offset, size, flags); } out: diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c index 9cec62cae7cb..a96ce162825e 100644 --- a/net/smc/smc_tx.c +++ b/net/smc/smc_tx.c @@ -235,7 +235,8 @@ int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len) */ if ((msg->msg_flags & MSG_OOB) && !send_remaining) conn->urg_tx_pend = true; - if ((msg->msg_flags & MSG_MORE || smc_tx_is_corked(smc)) && + if ((msg->msg_flags & MSG_MORE || smc_tx_is_corked(smc) || + msg->msg_flags & MSG_SENDPAGE_NOTLAST) && (atomic_read(&conn->sndbuf_space))) /* for a corked socket defer the RDMA writes if * sndbuf_space is still available. The applications @@ -257,6 +258,22 @@ int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len) return rc; } +int smc_tx_sendpage(struct smc_sock *smc, struct page *page, int offset, + size_t size, int flags) +{ + struct msghdr msg = {.msg_flags = flags}; + char *kaddr = kmap(page); + struct kvec iov; + int rc; + + iov.iov_base = kaddr + offset; + iov.iov_len = size; + iov_iter_kvec(&msg.msg_iter, WRITE, &iov, 1, size); + rc = smc_tx_sendmsg(smc, &msg, size); + kunmap(page); + return rc; +} + /***************************** sndbuf consumer *******************************/ /* sndbuf consumer: actual data transfer of one target chunk with ISM write */ diff --git a/net/smc/smc_tx.h b/net/smc/smc_tx.h index a59f370b8b43..34b578498b1f 100644 --- a/net/smc/smc_tx.h +++ b/net/smc/smc_tx.h @@ -31,6 +31,8 @@ void smc_tx_pending(struct smc_connection *conn); void smc_tx_work(struct work_struct *work); void smc_tx_init(struct smc_sock *smc); int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len); +int smc_tx_sendpage(struct smc_sock *smc, struct page *page, int offset, + size_t size, int flags); int smc_tx_sndbuf_nonempty(struct smc_connection *conn); void smc_tx_sndbuf_nonfull(struct smc_sock *smc); void smc_tx_consumer_update(struct smc_connection *conn, bool force);
This introduces a new corked flag, MSG_SENDPAGE_NOTLAST, which is involved in syscall sendfile() [1], it indicates this is not the last page. So we can cork the data until the page is not specify this flag. It has the same effect as MSG_MORE, but existed in sendfile() only. This patch adds a option MSG_SENDPAGE_NOTLAST for corking data, try to cork more data before sending when using sendfile(), which acts like TCP's behaviour. Also, this reimplements the default sendpage to inform that it is supported to some extent. [1] https://man7.org/linux/man-pages/man2/sendfile.2.html Signed-off-by: Tony Lu <tonylu@linux.alibaba.com> --- net/smc/af_smc.c | 4 +++- net/smc/smc_tx.c | 19 ++++++++++++++++++- net/smc/smc_tx.h | 2 ++ 3 files changed, 23 insertions(+), 2 deletions(-)