| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20250618030537.28394-1-yangfeng59949@163.com>
Date: Wed, 18 Jun 2025 11:05:37 +0800
From: Feng Yang <yangfeng59949@....com>
To: davem@...emloft.net,
edumazet@...gle.com,
kuba@...nel.org,
pabeni@...hat.com,
horms@...nel.org,
willemb@...gle.com,
almasrymina@...gle.com,
kerneljasonxing@...il.com,
ebiggers@...gle.com,
asml.silence@...il.com,
aleksander.lobakin@...el.com
Cc: yangfeng@...inos.cn,
netdev@...r.kernel.org,
linux-kernel@...r.kernel.org
Subject: [RFC PATCH net-next] skbuff: Improve the sending efficiency of __skb_send_sock
From: Feng Yang <yangfeng@...inos.cn>
By aggregating skb data into a bvec array for transmission, when using sockmap to forward large packets,
what previously required multiple transmissions now only needs a single transmission, which significantly enhances performance.
For small packets, the performance remains comparable to the original level.
Signed-off-by: Feng Yang <yangfeng@...inos.cn>
---
net/core/skbuff.c | 110 ++++++++++++++++++++++------------------------
1 file changed, 52 insertions(+), 58 deletions(-)
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 85fc82f72d26..19d78285a1c9 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3235,82 +3235,75 @@ typedef int (*sendmsg_func)(struct sock *sk, struct msghdr *msg);
static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset,
int len, sendmsg_func sendmsg, int flags)
{
- unsigned int orig_len = len;
struct sk_buff *head = skb;
unsigned short fragidx;
- int slen, ret;
+ struct msghdr msg;
+ struct bio_vec *bvec;
+ int max_vecs, ret;
+ int bvec_count = 0;
+ unsigned int copied = 0;
+
+ max_vecs = skb_shinfo(skb)->nr_frags + 1; // +1 for linear data
+ if (skb_has_frag_list(skb)) {
+ struct sk_buff *frag_skb = skb_shinfo(skb)->frag_list;
+
+ while (frag_skb) {
+ max_vecs += skb_shinfo(frag_skb)->nr_frags + 1; // +1 for linear data
+ frag_skb = frag_skb->next;
+ }
+ }
+
+ bvec = kcalloc(max_vecs, sizeof(struct bio_vec), GFP_KERNEL);
+ if (!bvec)
+ return -ENOMEM;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.msg_flags = MSG_SPLICE_PAGES | MSG_DONTWAIT | flags;
do_frag_list:
/* Deal with head data */
- while (offset < skb_headlen(skb) && len) {
- struct kvec kv;
- struct msghdr msg;
-
- slen = min_t(int, len, skb_headlen(skb) - offset);
- kv.iov_base = skb->data + offset;
- kv.iov_len = slen;
- memset(&msg, 0, sizeof(msg));
- msg.msg_flags = MSG_DONTWAIT | flags;
+ if (offset < skb_headlen(skb)) {
+ unsigned int copy_len = min(skb_headlen(skb) - offset, len - copied);
+ struct page *page = virt_to_page(skb->data + offset);
+ unsigned int page_offset = offset_in_page(skb->data + offset);
- iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &kv, 1, slen);
- ret = INDIRECT_CALL_2(sendmsg, sendmsg_locked,
- sendmsg_unlocked, sk, &msg);
- if (ret <= 0)
- goto error;
+ if (!sendpage_ok(page))
+ msg.msg_flags &= ~MSG_SPLICE_PAGES;
- offset += ret;
- len -= ret;
+ bvec_set_page(&bvec[bvec_count++], page, copy_len, page_offset);
+ copied += copy_len;
+ offset += copy_len;
}
- /* All the data was skb head? */
- if (!len)
- goto out;
-
/* Make offset relative to start of frags */
offset -= skb_headlen(skb);
- /* Find where we are in frag list */
- for (fragidx = 0; fragidx < skb_shinfo(skb)->nr_frags; fragidx++) {
- skb_frag_t *frag = &skb_shinfo(skb)->frags[fragidx];
+ if (copied < len) {
+ for (fragidx = 0; fragidx < skb_shinfo(skb)->nr_frags; fragidx++) {
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[fragidx];
+ unsigned int frag_size = skb_frag_size(frag);
- if (offset < skb_frag_size(frag))
- break;
-
- offset -= skb_frag_size(frag);
- }
-
- for (; len && fragidx < skb_shinfo(skb)->nr_frags; fragidx++) {
- skb_frag_t *frag = &skb_shinfo(skb)->frags[fragidx];
-
- slen = min_t(size_t, len, skb_frag_size(frag) - offset);
+ /* Find where we are in frag list */
+ if (offset >= frag_size) {
+ offset -= frag_size;
+ continue;
+ }
- while (slen) {
- struct bio_vec bvec;
- struct msghdr msg = {
- .msg_flags = MSG_SPLICE_PAGES | MSG_DONTWAIT |
- flags,
- };
+ unsigned int copy_len = min(frag_size - offset, len - copied);
- bvec_set_page(&bvec, skb_frag_page(frag), slen,
+ bvec_set_page(&bvec[bvec_count++], skb_frag_page(frag), copy_len,
skb_frag_off(frag) + offset);
- iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1,
- slen);
- ret = INDIRECT_CALL_2(sendmsg, sendmsg_locked,
- sendmsg_unlocked, sk, &msg);
- if (ret <= 0)
- goto error;
+ copied += copy_len;
+ offset = 0;
- len -= ret;
- offset += ret;
- slen -= ret;
+ if (copied >= len)
+ break;
}
-
- offset = 0;
}
- if (len) {
+ if (copied < len) {
/* Process any frag lists */
if (skb == head) {
@@ -3324,11 +3317,12 @@ static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset,
}
}
-out:
- return orig_len - len;
+ iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, bvec, bvec_count, len);
+ ret = INDIRECT_CALL_2(sendmsg, sendmsg_locked, sendmsg_unlocked, sk, &msg);
+
+ kfree(bvec);
-error:
- return orig_len == len ? ret : orig_len - len;
+ return ret;
}
/* Send skb data on a socket. Socket must be locked. */
--
2.43.0
Powered by blists - more mailing lists