git: 224aec05e732 - main - tcp: Initialize the maximum number of entries in a client cookie cache bucket

From: Zhenlei Huang <zlei_at_FreeBSD.org>
Date: Sat, 02 Sep 2023 20:36:44 UTC
The branch main has been updated by zlei:

URL: https://cgit.FreeBSD.org/src/commit/?id=224aec05e732bb97a0d3c91142973b98a91238d1

commit 224aec05e732bb97a0d3c91142973b98a91238d1
Author:     Zhenlei Huang <zlei@FreeBSD.org>
AuthorDate: 2023-09-02 20:34:07 +0000
Commit:     Zhenlei Huang <zlei@FreeBSD.org>
CommitDate: 2023-09-02 20:34:07 +0000

    tcp: Initialize the maximum number of entries in a client cookie cache bucket
    
    This vnet loader tunable is defined with SYSCTL_PROC, thus will not be
    initialized by kernel on vnet creating and will always have the default
    value TCP_FASTOPEN_CCACHE_BUCKET_LIMIT_DEFAULT.
    
    Fix by fetching the value from the corresponding kernel environment during
    vnet constructing.
    
    PR:             273509
    Reviewed by:    #transport, tuexen
    Fixes:  c560df6f12f1 This is an implementation of the client side of TCP Fast Open (TFO) [RFC7413]
    MFC after:      3 days
    Differential Revision:  https://reviews.freebsd.org/D41691
---
 sys/netinet/tcp_fastopen.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/sys/netinet/tcp_fastopen.c b/sys/netinet/tcp_fastopen.c
index 9b6f9c17b05c..c31225214d1d 100644
--- a/sys/netinet/tcp_fastopen.c
+++ b/sys/netinet/tcp_fastopen.c
@@ -271,7 +271,7 @@ SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, autokey,
 
 static int sysctl_net_inet_tcp_fastopen_ccache_bucket_limit(SYSCTL_HANDLER_ARGS);
 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, ccache_bucket_limit,
-    CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT,
+    CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_NEEDGIANT,
     NULL, 0, &sysctl_net_inet_tcp_fastopen_ccache_bucket_limit, "IU",
     "Max entries per bucket in client cookie cache");
 
@@ -393,7 +393,8 @@ tcp_fastopen_init(void)
 	V_tcp_fastopen_keys.newest = TCP_FASTOPEN_MAX_KEYS - 1;
 	V_tcp_fastopen_keys.newest_psk = TCP_FASTOPEN_MAX_PSKS - 1;
 
-	/* May already be non-zero if kernel tunable was set */
+	TUNABLE_INT_FETCH("net.inet.tcp.fastopen.ccache_bucket_limit",
+	    &V_tcp_fastopen_ccache.bucket_limit);
 	if (V_tcp_fastopen_ccache.bucket_limit == 0)
 		V_tcp_fastopen_ccache.bucket_limit =
 		    TCP_FASTOPEN_CCACHE_BUCKET_LIMIT_DEFAULT;