From: kerneljasonxing@gmail.com
To: davem@davemloft.net, kuba@kernel.org, ast@kernel.org,
daniel@iogearbox.net, hawk@kernel.org, john.fastabend@gmail.com,
andrii@kernel.org, kafai@fb.com, songliubraving@fb.com,
yhs@fb.com, kpsingh@kernel.org, edumazet@google.com,
atenart@kernel.org, alobakin@pm.me, weiwan@google.com,
bjorn@kernel.org, arnd@arndb.de, memxor@gmail.com
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
bpf@vger.kernel.org, kerneljasonxing@gmail.com,
Jason Xing <xingwanli@kuaishou.com>
Subject: [PATCH net] net: gro: flush the real oldest skb
Date: Wed, 27 Oct 2021 16:49:44 +0800 [thread overview]
Message-ID: <20211027084944.4508-1-kerneljasonxing@gmail.com> (raw)
From: Jason Xing <xingwanli@kuaishou.com>
Prior to this patch, when the count of skbs of one flow is larger than
MAX_GRO_SKBS, gro_flush_oldest() flushes the tail of the list. However,
as we can see in the merge part of skb_gro_receive(), the tail of the
list is the newest, head oldest.
Here, we need to fetch the real oldest one and then process it to lower
the latency.
Fix: 07d78363dc ("net: Convert NAPI gro list into a small hash table.")
Signed-off-by: Jason Xing <xingwanli@kuaishou.com>
---
net/core/dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/core/dev.c b/net/core/dev.c
index 7ee9fec..d52ebdb 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6012,7 +6012,7 @@ static void gro_flush_oldest(struct napi_struct *napi, struct list_head *head)
{
struct sk_buff *oldest;
- oldest = list_last_entry(head, struct sk_buff, list);
+ oldest = list_first_entry(head, struct sk_buff, list);
/* We are called with head length >= MAX_GRO_SKBS, so this is
* impossible.
--
1.8.3.1
next reply other threads:[~2021-10-27 8:50 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-27 8:49 kerneljasonxing [this message]
2021-10-27 13:59 ` [PATCH net] net: gro: flush the real oldest skb Jason Xing
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=20211027084944.4508-1-kerneljasonxing@gmail.com \
--to=kerneljasonxing@gmail.com \
--cc=alobakin@pm.me \
--cc=andrii@kernel.org \
--cc=arnd@arndb.de \
--cc=ast@kernel.org \
--cc=atenart@kernel.org \
--cc=bjorn@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=hawk@kernel.org \
--cc=john.fastabend@gmail.com \
--cc=kafai@fb.com \
--cc=kpsingh@kernel.org \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=memxor@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=songliubraving@fb.com \
--cc=weiwan@google.com \
--cc=xingwanli@kuaishou.com \
--cc=yhs@fb.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.
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 NNTP newsgroup(s).