diff options
author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-09-08 04:10:18 +0300 |
---|---|---|
committer | Jakub Kicinski <kuba@kernel.org> | 2022-09-20 20:21:49 +0300 |
commit | e9bd0cca09d13ac2f08d25e195203e42d4ad1ce8 (patch) | |
tree | c098713403c2ed7e70d310348766a1acf9d5e374 /net/ipv4/proc.c | |
parent | 08eaef90403110e51861d93e8008a355af467bbe (diff) | |
download | linux-e9bd0cca09d13ac2f08d25e195203e42d4ad1ce8.tar.xz |
tcp: Don't allocate tcp_death_row outside of struct netns_ipv4.
We will soon introduce an optional per-netns ehash and access hash
tables via net->ipv4.tcp_death_row->hashinfo instead of &tcp_hashinfo
in most places.
It could harm the fast path because dereferences of two fields in net
and tcp_death_row might incur two extra cache line misses. To save one
dereference, let's place tcp_death_row back in netns_ipv4 and fetch
hashinfo via net->ipv4.tcp_death_row"."hashinfo.
Note tcp_death_row was initially placed in netns_ipv4, and commit
fbb8295248e1 ("tcp: allocate tcp_death_row outside of struct netns_ipv4")
changed it to a pointer so that we can fire TIME_WAIT timers after freeing
net. However, we don't do so after commit 04c494e68a13 ("Revert "tcp/dccp:
get rid of inet_twsk_purge()""), so we need not define tcp_death_row as a
pointer.
Also, we move refcount_dec_and_test(&tw_refcount) from tcp_sk_exit() to
tcp_sk_exit_batch() as a debug check.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv4/proc.c')
-rw-r--r-- | net/ipv4/proc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c index 0088a4c64d77..5386f460bd20 100644 --- a/net/ipv4/proc.c +++ b/net/ipv4/proc.c @@ -59,7 +59,7 @@ static int sockstat_seq_show(struct seq_file *seq, void *v) socket_seq_show(seq); seq_printf(seq, "TCP: inuse %d orphan %d tw %d alloc %d mem %ld\n", sock_prot_inuse_get(net, &tcp_prot), orphans, - refcount_read(&net->ipv4.tcp_death_row->tw_refcount) - 1, + refcount_read(&net->ipv4.tcp_death_row.tw_refcount) - 1, sockets, proto_memory_allocated(&tcp_prot)); seq_printf(seq, "UDP: inuse %d mem %ld\n", sock_prot_inuse_get(net, &udp_prot), |