diff options
| author |   Eric Dumazet <edumazet@google.com> | 2021-07-19 03:11:07 -0700 |
|---|---|---|
| committer |   Jakub Kicinski <kuba@kernel.org> | 2021-07-20 12:07:07 +0200 |
| commit | e93abb840a2c356ed2809c31fcedb058601ac2e4 (patch) | |
| tree | e52a6fb74dce8895a5314955875df8b9287f94f7 | |
| parent | netlink: Deal with ESRCH error in nlmsg_notify() (diff) | |
| download | linux-dev-e93abb840a2c356ed2809c31fcedb058601ac2e4.tar.xz linux-dev-e93abb840a2c356ed2809c31fcedb058601ac2e4.zip | |
net/tcp_fastopen: remove tcp_fastopen_ctx_lock
Remove the (per netns) spinlock in favor of xchg() atomic operations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Wei Wang <weiwan@google.com>
Link: https://lore.kernel.org/r/20210719101107.3203943-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | include/net/netns/ipv4.h | 1 | ||||
| -rw-r--r-- | net/ipv4/tcp_fastopen.c | 17 | ||||
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 1 |
3 files changed, 3 insertions, 16 deletions
diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h index b8620519eace..2f65701a43c9 100644 --- a/include/net/netns/ipv4.h +++ b/include/net/netns/ipv4.h @@ -174,7 +174,6 @@ struct netns_ipv4 { int sysctl_tcp_fastopen; const struct tcp_congestion_ops __rcu *tcp_congestion_control; struct tcp_fastopen_context __rcu *tcp_fastopen_ctx; - spinlock_t tcp_fastopen_ctx_lock; unsigned int sysctl_tcp_fastopen_blackhole_timeout; atomic_t tfo_active_disable_times; unsigned long tfo_active_disable_stamp; diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c index 47c32604d38f..1a9fbd5448a7 100644 --- a/net/ipv4/tcp_fastopen.c +++ b/net/ipv4/tcp_fastopen.c @@ -55,12 +55,7 @@ void tcp_fastopen_ctx_destroy(struct net *net) { struct tcp_fastopen_context *ctxt; - spin_lock(&net->ipv4.tcp_fastopen_ctx_lock); - - ctxt = rcu_dereference_protected(net->ipv4.tcp_fastopen_ctx, - lockdep_is_held(&net->ipv4.tcp_fastopen_ctx_lock)); - rcu_assign_pointer(net->ipv4.tcp_fastopen_ctx, NULL); - spin_unlock(&net->ipv4.tcp_fastopen_ctx_lock); + ctxt = xchg((__force struct tcp_fastopen_context **)&net->ipv4.tcp_fastopen_ctx, NULL); if (ctxt) call_rcu(&ctxt->rcu, tcp_fastopen_ctx_free); @@ -89,18 +84,12 @@ int tcp_fastopen_reset_cipher(struct net *net, struct sock *sk, ctx->num = 1; } - spin_lock(&net->ipv4.tcp_fastopen_ctx_lock); if (sk) { q = &inet_csk(sk)->icsk_accept_queue.fastopenq; - octx = rcu_dereference_protected(q->ctx, - lockdep_is_held(&net->ipv4.tcp_fastopen_ctx_lock)); - rcu_assign_pointer(q->ctx, ctx); + octx = xchg((__force struct tcp_fastopen_context **)&q->ctx, ctx); } else { - octx = rcu_dereference_protected(net->ipv4.tcp_fastopen_ctx, - lockdep_is_held(&net->ipv4.tcp_fastopen_ctx_lock)); - rcu_assign_pointer(net->ipv4.tcp_fastopen_ctx, ctx); + octx = xchg((__force struct tcp_fastopen_context **)&net->ipv4.tcp_fastopen_ctx, ctx); } - spin_unlock(&net->ipv4.tcp_fastopen_ctx_lock); if (octx) call_rcu(&octx->rcu, tcp_fastopen_ctx_free); diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index b9dc2d6197be..e9321dd39cdb 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2964,7 +2964,6 @@ static int __net_init tcp_sk_init(struct net *net) net->ipv4.sysctl_tcp_comp_sack_slack_ns = 100 * NSEC_PER_USEC; net->ipv4.sysctl_tcp_comp_sack_nr = 44; net->ipv4.sysctl_tcp_fastopen = TFO_CLIENT_ENABLE; - spin_lock_init(&net->ipv4.tcp_fastopen_ctx_lock); net->ipv4.sysctl_tcp_fastopen_blackhole_timeout = 60 * 60; atomic_set(&net->ipv4.tfo_active_disable_times, 0); |