diff options
| author | Eric Dumazet <edumazet@google.com> | 2026-01-28 18:55:47 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-01-29 18:47:21 -0800 |
| commit | b1cd687e3e387aafde03ae3d862ef44410131ae4 (patch) | |
| tree | 2fbc145298b7c0b46824b81b0b96f16db6f9b21d | |
| parent | 70e9a5760abfb6338d63994d4de6b0778ec795d6 (diff) | |
ipv6: optimize fl6_update_dst()
fl6_update_dst() is called for every TCP (and others) transmit,
and is a nop for common cases.
Split it in two parts :
1) fl6_update_dst() inline helper, small and fast.
2) __fl6_update_dst() for the exception, out of line.
Small size increase to get better TX performance.
$ scripts/bloat-o-meter -t vmlinux.old vmlinux.new
add/remove: 2/2 grow/shrink: 8/0 up/down: 296/-125 (171)
Function old new delta
__fl6_update_dst - 104 +104
rawv6_sendmsg 2244 2284 +40
udpv6_sendmsg 3013 3043 +30
tcp_v6_connect 1514 1534 +20
cookie_v6_check 1501 1519 +18
ip6_datagram_dst_update 673 690 +17
inet6_sk_rebuild_header 499 516 +17
inet6_csk_route_socket 507 524 +17
inet6_csk_route_req 343 360 +17
__pfx___fl6_update_dst - 16 +16
__pfx_fl6_update_dst 16 - -16
fl6_update_dst 109 - -109
Total: Before=22570304, After=22570475, chg +0.00%
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260128185548.3738781-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | include/net/ipv6.h | 16 | ||||
| -rw-r--r-- | net/ipv6/exthdrs.c | 14 |
2 files changed, 20 insertions, 10 deletions
diff --git a/include/net/ipv6.h b/include/net/ipv6.h index c7f597da01cd..cf2203ff2bfd 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -1174,9 +1174,19 @@ int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target, int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type); -struct in6_addr *fl6_update_dst(struct flowi6 *fl6, - const struct ipv6_txoptions *opt, - struct in6_addr *orig); +struct in6_addr *__fl6_update_dst(struct flowi6 *fl6, + const struct ipv6_txoptions *opt, + struct in6_addr *orig); + +static inline struct in6_addr * +fl6_update_dst(struct flowi6 *fl6, const struct ipv6_txoptions *opt, + struct in6_addr *orig) +{ + if (likely(!opt)) + return NULL; + + return __fl6_update_dst(fl6, opt, orig); +} /* * socket options (ipv6_sockglue.c) diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c index 54088fa0c09d..cd318ff0dcd8 100644 --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -1336,21 +1336,21 @@ struct ipv6_txoptions *__ipv6_fixup_options(struct ipv6_txoptions *opt_space, EXPORT_SYMBOL_GPL(__ipv6_fixup_options); /** - * fl6_update_dst - update flowi destination address with info given + * __fl6_update_dst - update flowi destination address with info given * by srcrt option, if any. * * @fl6: flowi6 for which daddr is to be updated * @opt: struct ipv6_txoptions in which to look for srcrt opt * @orig: copy of original daddr address if modified * - * Returns NULL if no txoptions or no srcrt, otherwise returns orig + * Return: NULL if no srcrt or invalid srcrt type, otherwise returns orig * and initial value of fl6->daddr set in orig */ -struct in6_addr *fl6_update_dst(struct flowi6 *fl6, - const struct ipv6_txoptions *opt, - struct in6_addr *orig) +struct in6_addr *__fl6_update_dst(struct flowi6 *fl6, + const struct ipv6_txoptions *opt, + struct in6_addr *orig) { - if (!opt || !opt->srcrt) + if (!opt->srcrt) return NULL; *orig = fl6->daddr; @@ -1374,4 +1374,4 @@ struct in6_addr *fl6_update_dst(struct flowi6 *fl6, return orig; } -EXPORT_SYMBOL_GPL(fl6_update_dst); +EXPORT_SYMBOL_GPL(__fl6_update_dst); |