From 7aa5470c2c09265902b5e4289afa82e4e7c2987e Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Sat, 3 Dec 2016 11:14:57 -0800
Subject: [PATCH 08/10] tcp: tsq: move tsq_flags close to sk_wmem_alloc
tsq_flags being in the same cache line than sk_wmem_alloc
makes a lot of sense. Both fields are changed from tcp_wfree()
and more generally by various TSQ related functions.
Prior patch made room in struct sock and added sk_tsq_flags,
this patch deletes tsq_flags from struct tcp_sock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
include/linux/tcp.h | 1 -
net/ipv4/tcp.c | 4 ++--
net/ipv4/tcp_ipv4.c | 2 +-
net/ipv4/tcp_output.c | 24 +++++++++++-------------
net/ipv4/tcp_timer.c | 4 ++--
net/ipv6/tcp_ipv6.c | 2 +-
6 files changed, 17 insertions(+), 20 deletions(-)
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -192,7 +192,6 @@ struct tcp_sock {
u32 tsoffset; /* timestamp offset */
struct list_head tsq_node; /* anchor in tsq_tasklet.head list */
- unsigned long tsq_flags;
/* Data for direct copy to user */
struct {
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -665,9 +665,9 @@ static void tcp_push(struct sock *sk, in
if (tcp_should_autocork(sk, skb, size_goal)) {
/* avoid atomic op if TSQ_THROTTLED bit is already set */
- if (!test_bit(TSQ_THROTTLED, &tp->tsq_flags)) {
+ if (!test_bit(TSQ_THROTTLED, &sk->sk_tsq_flags)) {
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAUTOCORKING);
- set_bit(TSQ_THROTTLED, &tp->tsq_flags);
+ set_bit(TSQ_THROTTLED, &sk->sk_tsq_flags);
}
/* It is possible TX completion already happened
* before we set TSQ_THROTTLED.
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -446,7 +446,7 @@ void tcp_v4_err(struct sk_buff *icmp_skb
if (!sock_owned_by_user(sk)) {
tcp_v4_mtu_reduced(sk);
} else {
- if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &tp->tsq_flags))
+ if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &sk->sk_tsq_flags))
sock_hold(sk);
}
goto out;
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -773,14 +773,15 @@ static void tcp_tasklet_func(unsigned lo
list_for_each_safe(q, n, &list) {
tp = list_entry(q, struct tcp_sock, tsq_node);
list_del(&tp->tsq_node);
- clear_bit(TSQ_QUEUED, &tp->tsq_flags);
sk = (struct sock *)tp;
+ clear_bit(TSQ_QUEUED, &sk->sk_tsq_flags);
+
if (!sk->sk_lock.owned &&
- test_bit(TCP_TSQ_DEFERRED, &tp->tsq_flags)) {
+ test_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags)) {
bh_lock_sock(sk);
if (!sock_owned_by_user(sk)) {
- clear_bit(TCP_TSQ_DEFERRED, &tp->tsq_flags);
+ clear_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags);
tcp_tsq_handler(sk);
}
bh_unlock_sock(sk);
@@ -803,16 +804,15 @@ static void tcp_tasklet_func(unsigned lo
*/
void tcp_release_cb(struct sock *sk)
{
- struct tcp_sock *tp = tcp_sk(sk);
unsigned long flags, nflags;
/* perform an atomic operation only if at least one flag is set */
do {
- flags = tp->tsq_flags;
+ flags = sk->sk_tsq_flags;
if (!(flags & TCP_DEFERRED_ALL))
return;
nflags = flags & ~TCP_DEFERRED_ALL;
- } while (cmpxchg(&tp->tsq_flags, flags, nflags) != flags);
+ } while (cmpxchg(&sk->sk_tsq_flags, flags, nflags) != flags);
if (flags & TCPF_TSQ_DEFERRED)
tcp_tsq_handler(sk);
@@ -884,7 +884,7 @@ void tcp_wfree(struct sk_buff *skb)
if (wmem >= SKB_TRUESIZE(1) && this_cpu_ksoftirqd() == current)
goto out;
- for (oval = READ_ONCE(tp->tsq_flags);; oval = nval) {
+ for (oval = READ_ONCE(sk->sk_tsq_flags);; oval = nval) {
struct tsq_tasklet *tsq;
bool empty;
@@ -892,7 +892,7 @@ void tcp_wfree(struct sk_buff *skb)
goto out;
nval = (oval & ~TSQF_THROTTLED) | TSQF_QUEUED | TCPF_TSQ_DEFERRED;
- nval = cmpxchg(&tp->tsq_flags, oval, nval);
+ nval = cmpxchg(&sk->sk_tsq_flags, oval, nval);
if (nval != oval)
continue;
@@ -2151,7 +2151,7 @@ static bool tcp_small_queue_check(struct
skb->prev == sk->sk_write_queue.next)
return false;
- set_bit(TSQ_THROTTLED, &tcp_sk(sk)->tsq_flags);
+ set_bit(TSQ_THROTTLED, &sk->sk_tsq_flags);
/* It is possible TX completion already happened
* before we set TSQ_THROTTLED, so we must
* test again the condition.
@@ -2249,8 +2249,8 @@ static bool tcp_write_xmit(struct sock *
unlikely(tso_fragment(sk, skb, limit, mss_now, gfp)))
break;
- if (test_bit(TCP_TSQ_DEFERRED, &tp->tsq_flags))
- clear_bit(TCP_TSQ_DEFERRED, &tp->tsq_flags);
+ if (test_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags))
+ clear_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags);
if (tcp_small_queue_check(sk, skb, 0))
break;
@@ -3561,8 +3561,6 @@ void __tcp_send_ack(struct sock *sk, u32
/* We do not want pure acks influencing TCP Small Queues or fq/pacing
* too much.
* SKB_TRUESIZE(max(1 .. 66, MAX_TCP_HEADER)) is unfortunately ~784
- * We also avoid tcp_wfree() overhead (cache line miss accessing
- * tp->tsq_flags) by using regular sock_wfree()
*/
skb_set_tcp_pure_ack(buff);
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -327,7 +327,7 @@ static void tcp_delack_timer(unsigned lo
inet_csk(sk)->icsk_ack.blocked = 1;
__NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOCKED);
/* deleguate our work to tcp_release_cb() */
- if (!test_and_set_bit(TCP_DELACK_TIMER_DEFERRED, &tcp_sk(sk)->tsq_flags))
+ if (!test_and_set_bit(TCP_DELACK_TIMER_DEFERRED, &sk->sk_tsq_flags))
sock_hold(sk);
}
bh_unlock_sock(sk);
@@ -610,7 +610,7 @@ static void tcp_write_timer(unsigned lon
tcp_write_timer_handler(sk);
} else {
/* delegate our work to tcp_release_cb() */
- if (!test_and_set_bit(TCP_WRITE_TIMER_DEFERRED, &tcp_sk(sk)->tsq_flags))
+ if (!test_and_set_bit(TCP_WRITE_TIMER_DEFERRED, &sk->sk_tsq_flags))
sock_hold(sk);
}
bh_unlock_sock(sk);
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -404,7 +404,7 @@ static void tcp_v6_err(struct sk_buff *s
if (!sock_owned_by_user(sk))
tcp_v6_mtu_reduced(sk);
else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED,
- &tp->tsq_flags))
+ &sk->sk_tsq_flags))
sock_hold(sk);
goto out;
}