From: David Gibson <david@gibson.dropbear.id.au>
To: Stefano Brivio <sbrivio@redhat.com>, passt-dev@passt.top
Cc: David Gibson <david@gibson.dropbear.id.au>
Subject: [PATCH v2 03/18] tcp: Combine two parts of passt tap send path together
Date: Fri, 9 Dec 2022 16:42:13 +1100 [thread overview]
Message-ID: <20221209054228.4085990-4-david@gibson.dropbear.id.au> (raw)
In-Reply-To: <20221209054228.4085990-1-david@gibson.dropbear.id.au>
tcp_l2_buf_flush() open codes the "primary" send of message to the passt
tap interface, but calls tcp_l2_buf_flush_part() to handle the case of a
short send. Combine these two passt-specific operations into
tcp_l2_buf_flush_passt() which is a little cleaner and will enable furrther
cleanups.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
tcp.c | 22 +++++++++++++---------
1 file changed, 13 insertions(+), 9 deletions(-)
diff --git a/tcp.c b/tcp.c
index ed65a9e..fe788b4 100644
--- a/tcp.c
+++ b/tcp.c
@@ -1415,22 +1415,28 @@ static int tcp_l2_buf_write_one(struct ctx *c, const struct iovec *iov)
}
/**
- * tcp_l2_buf_flush_part() - Ensure a complete last message on partial sendmsg()
+ * tcp_l2_buf_flush_passt() - Send a message on the passt tap interface
* @c: Execution context
* @mh: Message header that was partially sent by sendmsg()
- * @sent: Bytes already sent
+ * @buf_bytes: Total number of bytes to send
*/
-static void tcp_l2_buf_flush_part(const struct ctx *c,
- const struct msghdr *mh, size_t sent)
+static void tcp_l2_buf_flush_passt(const struct ctx *c,
+ const struct msghdr *mh, size_t buf_bytes)
{
- size_t end = 0, missing;
+ size_t end = 0, missing, sent;
struct iovec *iov;
unsigned int i;
+ ssize_t n;
char *p;
+ n = sendmsg(c->fd_tap, mh, MSG_NOSIGNAL | MSG_DONTWAIT);
+ if (n < 0 || ((sent = (size_t)n) == buf_bytes))
+ return;
+
+ /* Ensure a complete last message on partial sendmsg() */
for (i = 0, iov = mh->msg_iov; i < mh->msg_iovlen; i++, iov++) {
end += iov->iov_len;
- if (end >= sent)
+ if (end >= (size_t)sent)
break;
}
@@ -1454,9 +1460,7 @@ static void tcp_l2_buf_flush(struct ctx *c, struct msghdr *mh,
return;
if (c->mode == MODE_PASST) {
- size_t n = sendmsg(c->fd_tap, mh, MSG_NOSIGNAL | MSG_DONTWAIT);
- if (n > 0 && n < *buf_bytes)
- tcp_l2_buf_flush_part(c, mh, n);
+ tcp_l2_buf_flush_passt(c, mh, *buf_bytes);
} else {
size_t i;
--
@@ -1415,22 +1415,28 @@ static int tcp_l2_buf_write_one(struct ctx *c, const struct iovec *iov)
}
/**
- * tcp_l2_buf_flush_part() - Ensure a complete last message on partial sendmsg()
+ * tcp_l2_buf_flush_passt() - Send a message on the passt tap interface
* @c: Execution context
* @mh: Message header that was partially sent by sendmsg()
- * @sent: Bytes already sent
+ * @buf_bytes: Total number of bytes to send
*/
-static void tcp_l2_buf_flush_part(const struct ctx *c,
- const struct msghdr *mh, size_t sent)
+static void tcp_l2_buf_flush_passt(const struct ctx *c,
+ const struct msghdr *mh, size_t buf_bytes)
{
- size_t end = 0, missing;
+ size_t end = 0, missing, sent;
struct iovec *iov;
unsigned int i;
+ ssize_t n;
char *p;
+ n = sendmsg(c->fd_tap, mh, MSG_NOSIGNAL | MSG_DONTWAIT);
+ if (n < 0 || ((sent = (size_t)n) == buf_bytes))
+ return;
+
+ /* Ensure a complete last message on partial sendmsg() */
for (i = 0, iov = mh->msg_iov; i < mh->msg_iovlen; i++, iov++) {
end += iov->iov_len;
- if (end >= sent)
+ if (end >= (size_t)sent)
break;
}
@@ -1454,9 +1460,7 @@ static void tcp_l2_buf_flush(struct ctx *c, struct msghdr *mh,
return;
if (c->mode == MODE_PASST) {
- size_t n = sendmsg(c->fd_tap, mh, MSG_NOSIGNAL | MSG_DONTWAIT);
- if (n > 0 && n < *buf_bytes)
- tcp_l2_buf_flush_part(c, mh, n);
+ tcp_l2_buf_flush_passt(c, mh, *buf_bytes);
} else {
size_t i;
--
2.38.1
next prev parent reply other threads:[~2022-12-09 5:42 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-12-09 5:42 [PATCH v2 00/18] RFC: Unify and simplify tap send path David Gibson
2022-12-09 5:42 ` [PATCH v2 01/18] pcap: Introduce pcap_frame() helper David Gibson
2023-01-04 17:45 ` Stefano Brivio
2023-01-05 4:47 ` David Gibson
2022-12-09 5:42 ` [PATCH v2 02/18] pcap: Replace pcapm() with pcap_multiple() David Gibson
2022-12-09 5:42 ` David Gibson [this message]
2022-12-09 5:42 ` [PATCH v2 04/18] tcp: Don't keep compute total bytes in a message until we need it David Gibson
2023-01-04 17:45 ` Stefano Brivio
2023-01-05 4:48 ` David Gibson
2022-12-09 5:42 ` [PATCH v2 05/18] tcp: Improve interface to tcp_l2_buf_flush() David Gibson
2023-01-04 17:45 ` Stefano Brivio
2023-01-05 4:53 ` David Gibson
2022-12-09 5:42 ` [PATCH v2 06/18] tcp: Combine two parts of pasta tap send path together David Gibson
2022-12-09 5:42 ` [PATCH v2 07/18] tap, tcp: Move tap send path to tap.c David Gibson
2022-12-09 5:42 ` [PATCH v2 08/18] util: Introduce hton*_constant() in place of #ifdefs David Gibson
2022-12-09 5:42 ` [PATCH v2 09/18] tcp, udp: Use named field initializers in iov_init functions David Gibson
2022-12-09 5:42 ` [PATCH v2 10/18] util: Parameterize ethernet header initializer macro David Gibson
2022-12-09 5:42 ` [PATCH v2 11/18] tcp: Remove redundant and incorrect initialization from *_iov_init() David Gibson
2022-12-09 5:42 ` [PATCH v2 12/18] tcp: Consolidate calculation of total frame size David Gibson
2022-12-09 5:42 ` [PATCH v2 13/18] tap: Add "tap headers" abstraction David Gibson
2022-12-09 5:42 ` [PATCH v2 14/18] tcp: Use abstracted tap header David Gibson
2022-12-09 5:42 ` [PATCH v2 15/18] tap: Use different io vector bases depending on tap type David Gibson
2022-12-09 5:42 ` [PATCH v2 16/18] udp: Use abstracted tap header David Gibson
2022-12-09 5:42 ` [PATCH v2 17/18] udp: Use tap_send_frames() David Gibson
2023-01-04 17:45 ` Stefano Brivio
2023-01-05 4:54 ` David Gibson
2022-12-09 5:42 ` [PATCH v2 18/18] tap: Improve handling of partial frame sends David Gibson
2023-01-04 17:45 ` Stefano Brivio
2023-01-05 4:57 ` David Gibson
2023-01-04 17:45 ` [PATCH v2 00/18] RFC: Unify and simplify tap send path Stefano Brivio
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20221209054228.4085990-4-david@gibson.dropbear.id.au \
--to=david@gibson.dropbear.id.au \
--cc=passt-dev@passt.top \
--cc=sbrivio@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://passt.top/passt
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for IMAP folder(s).