[PATCH net-next 04/15] tcp: Namespace-ify sysctl_tcp_slow_start_after_idle

[Eric Dumazet]

Signed-off-by: Eric Dumazet <eduma...@google.com>
---
 include/net/netns/ipv4.h   |  1 +
 include/net/tcp.h          |  3 +--
 net/ipv4/sysctl_net_ipv4.c | 14 +++++++-------
 net/ipv4/tcp_ipv4.c        |  1 +
 net/ipv4/tcp_output.c      |  5 +----
 5 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h
index 
2a9f37b39c45fe451e45025790a4e5c45ece5cbc..8662692686b3af98a94a176230b9ed147881d87a
 100644
--- a/include/net/netns/ipv4.h
+++ b/include/net/netns/ipv4.h
@@ -131,6 +131,7 @@ struct netns_ipv4 {
        int sysctl_tcp_early_retrans;
        int sysctl_tcp_recovery;
        int sysctl_tcp_thin_linear_timeouts;
+       int sysctl_tcp_slow_start_after_idle;
        struct inet_timewait_death_row tcp_death_row;
        int sysctl_max_syn_backlog;
        int sysctl_tcp_fastopen;
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 
8ef12bfe1a3a7083f1bbc924bc43a022a4057768..09c79705a0742aa8c22b3b7795d01b6c685d32e2
 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -259,7 +259,6 @@ extern int sysctl_tcp_nometrics_save;
 extern int sysctl_tcp_moderate_rcvbuf;
 extern int sysctl_tcp_tso_win_divisor;
 extern int sysctl_tcp_workaround_signed_windows;
-extern int sysctl_tcp_slow_start_after_idle;
 
 #define TCP_RACK_LOSS_DETECTION  0x1 /* Use RACK to detect losses */
 
@@ -1305,7 +1304,7 @@ static inline void tcp_slow_start_after_idle_check(struct 
sock *sk)
        struct tcp_sock *tp = tcp_sk(sk);
        s32 delta;
 
-       if (!sysctl_tcp_slow_start_after_idle || tp->packets_out ||
+       if (!sock_net(sk)->ipv4.sysctl_tcp_slow_start_after_idle || 
tp->packets_out ||
            ca_ops->cong_control)
                return;
        delta = tcp_jiffies32 - tp->lsndtime;
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index 
12003214f4d80b38d5f754ddd91be8a990168ade..40d69af8b363bc236e23879973872d8f9346d85e
 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -571,13 +571,6 @@ static struct ctl_table ipv4_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec
        },
-       {
-               .procname       = "tcp_slow_start_after_idle",
-               .data           = &sysctl_tcp_slow_start_after_idle,
-               .maxlen         = sizeof(int),
-               .mode           = 0644,
-               .proc_handler   = proc_dointvec
-       },
 #ifdef CONFIG_NETLABEL
        {
                .procname       = "cipso_cache_enable",
@@ -1145,6 +1138,13 @@ static struct ctl_table ipv4_net_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec
        },
+       {
+               .procname       = "tcp_slow_start_after_idle",
+               .data           = 
&init_net.ipv4.sysctl_tcp_slow_start_after_idle,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = proc_dointvec
+       },
        { }
 };
 
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 
517ff1948a71287b06ea0859e1f25a15119a3dd9..cea63a4b59655823def7a423d27191003c7f084c
 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -2486,6 +2486,7 @@ static int __net_init tcp_sk_init(struct net *net)
        net->ipv4.sysctl_tcp_timestamps = 1;
        net->ipv4.sysctl_tcp_early_retrans = 3;
        net->ipv4.sysctl_tcp_recovery = TCP_RACK_LOSS_DETECTION;
+       net->ipv4.sysctl_tcp_slow_start_after_idle = 1; /* By default, RFC2861 
behavior.  */
 
        net->ipv4.sysctl_tcp_fastopen = TFO_CLIENT_ENABLE;
        spin_lock_init(&net->ipv4.tcp_fastopen_ctx_lock);
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 
dd7c22b7d23b016b1da83138d6e8047abdef97e6..bc93a346e6e91289c2aeb2f2d2522b809da12dd6
 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -61,9 +61,6 @@ int sysctl_tcp_limit_output_bytes __read_mostly = 262144;
  */
 int sysctl_tcp_tso_win_divisor __read_mostly = 3;
 
-/* By default, RFC2861 behavior.  */
-int sysctl_tcp_slow_start_after_idle __read_mostly = 1;
-
 static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
                           int push_one, gfp_t gfp);
 
@@ -1633,7 +1630,7 @@ static void tcp_cwnd_validate(struct sock *sk, bool 
is_cwnd_limited)
                if (tp->packets_out > tp->snd_cwnd_used)
                        tp->snd_cwnd_used = tp->packets_out;
 
-               if (sysctl_tcp_slow_start_after_idle &&
+               if (sock_net(sk)->ipv4.sysctl_tcp_slow_start_after_idle &&
                    (s32)(tcp_jiffies32 - tp->snd_cwnd_stamp) >= 
inet_csk(sk)->icsk_rto &&
                    !ca_ops->cong_control)
                        tcp_cwnd_application_limited(sk);
-- 
2.15.0.rc2.357.g7e34df9404-goog