Commit 356d1833 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

tcp: Namespace-ify sysctl_tcp_rmem and sysctl_tcp_wmem 



Note that when a new netns is created, it inherits its
sysctl_tcp_rmem and sysctl_tcp_wmem from initial netns.

This change is needed so that we can refine TCP rcvbuf autotuning,
to take RTT into consideration.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Wei Wang <weiwan@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a3dcaf17

include/net/netns/ipv4.h

+2 −0
Original line number Diff line number Diff line
@@ -155,6 +155,8 @@ struct netns_ipv4 { 
	int sysctl_tcp_invalid_ratelimit;

	int sysctl_tcp_pacing_ss_ratio;

	int sysctl_tcp_pacing_ca_ratio;

	int sysctl_tcp_wmem[3];

	int sysctl_tcp_rmem[3];

	struct inet_timewait_death_row tcp_death_row;

	int sysctl_max_syn_backlog;

	int sysctl_tcp_fastopen;

include/net/tcp.h

+0 −2
Original line number Diff line number Diff line
@@ -242,8 +242,6 @@ void tcp_time_wait(struct sock *sk, int state, int timeo); 
/* sysctl variables for tcp */

extern int sysctl_tcp_max_orphans;

extern long sysctl_tcp_mem[3];

extern int sysctl_tcp_wmem[3];

extern int sysctl_tcp_rmem[3];



#define TCP_RACK_LOSS_DETECTION  0x1 /* Use RACK to detect losses */

#define TCP_RACK_STATIC_REO_WND  0x2 /* Use static RACK reo wnd */

net/ipv4/sysctl_net_ipv4.c

+16 −16
Original line number Diff line number Diff line
@@ -440,22 +440,6 @@ static struct ctl_table ipv4_table[] = { 
		.mode		= 0644,

		.proc_handler	= proc_doulongvec_minmax,

	},

	{

		.procname	= "tcp_wmem",

		.data		= &sysctl_tcp_wmem,

		.maxlen		= sizeof(sysctl_tcp_wmem),

		.mode		= 0644,

		.proc_handler	= proc_dointvec_minmax,

		.extra1		= &one,

	},

	{

		.procname	= "tcp_rmem",

		.data		= &sysctl_tcp_rmem,

		.maxlen		= sizeof(sysctl_tcp_rmem),

		.mode		= 0644,

		.proc_handler	= proc_dointvec_minmax,

		.extra1		= &one,

	},

	{

		.procname	= "tcp_low_latency",

		.data		= &sysctl_tcp_low_latency,
@@ -1164,6 +1148,22 @@ static struct ctl_table ipv4_net_table[] = { 
		.extra1		= &zero,

		.extra2		= &thousand,

	},

	{

		.procname	= "tcp_wmem",

		.data		= &init_net.ipv4.sysctl_tcp_wmem,

		.maxlen		= sizeof(init_net.ipv4.sysctl_tcp_wmem),

		.mode		= 0644,

		.proc_handler	= proc_dointvec_minmax,

		.extra1		= &one,

	},

	{

		.procname	= "tcp_rmem",

		.data		= &init_net.ipv4.sysctl_tcp_rmem,

		.maxlen		= sizeof(init_net.ipv4.sysctl_tcp_rmem),

		.mode		= 0644,

		.proc_handler	= proc_dointvec_minmax,

		.extra1		= &one,

	},

	{ }

};

net/ipv4/tcp.c

+8 −13
Original line number Diff line number Diff line
@@ -289,12 +289,7 @@ struct percpu_counter tcp_orphan_count; 
EXPORT_SYMBOL_GPL(tcp_orphan_count);



long sysctl_tcp_mem[3] __read_mostly;

int sysctl_tcp_wmem[3] __read_mostly;

int sysctl_tcp_rmem[3] __read_mostly;



EXPORT_SYMBOL(sysctl_tcp_mem);

EXPORT_SYMBOL(sysctl_tcp_rmem);

EXPORT_SYMBOL(sysctl_tcp_wmem);



atomic_long_t tcp_memory_allocated;	/* Current allocated memory. */

EXPORT_SYMBOL(tcp_memory_allocated);
@@ -456,8 +451,8 @@ void tcp_init_sock(struct sock *sk) 


	icsk->icsk_sync_mss = tcp_sync_mss;



	sk->sk_sndbuf = sysctl_tcp_wmem[1];

	sk->sk_rcvbuf = sysctl_tcp_rmem[1];

	sk->sk_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[1];

	sk->sk_rcvbuf = sock_net(sk)->ipv4.sysctl_tcp_rmem[1];



	sk_sockets_allocated_inc(sk);

}
@@ -3636,13 +3631,13 @@ void __init tcp_init(void) 
	max_wshare = min(4UL*1024*1024, limit);

	max_rshare = min(6UL*1024*1024, limit);



	sysctl_tcp_wmem[0] = SK_MEM_QUANTUM;

	sysctl_tcp_wmem[1] = 16*1024;

	sysctl_tcp_wmem[2] = max(64*1024, max_wshare);

	init_net.ipv4.sysctl_tcp_wmem[0] = SK_MEM_QUANTUM;

	init_net.ipv4.sysctl_tcp_wmem[1] = 16*1024;

	init_net.ipv4.sysctl_tcp_wmem[2] = max(64*1024, max_wshare);



	sysctl_tcp_rmem[0] = SK_MEM_QUANTUM;

	sysctl_tcp_rmem[1] = 87380;

	sysctl_tcp_rmem[2] = max(87380, max_rshare);

	init_net.ipv4.sysctl_tcp_rmem[0] = SK_MEM_QUANTUM;

	init_net.ipv4.sysctl_tcp_rmem[1] = 87380;

	init_net.ipv4.sysctl_tcp_rmem[2] = max(87380, max_rshare);



	pr_info("Hash tables configured (established %u bind %u)\n",

		tcp_hashinfo.ehash_mask + 1, tcp_hashinfo.bhash_size);

net/ipv4/tcp_input.c

+8 −6
Original line number Diff line number Diff line
@@ -320,7 +320,7 @@ static void tcp_sndbuf_expand(struct sock *sk) 
	sndmem *= nr_segs * per_mss;



	if (sk->sk_sndbuf < sndmem)

		sk->sk_sndbuf = min(sndmem, sysctl_tcp_wmem[2]);

		sk->sk_sndbuf = min(sndmem, sock_net(sk)->ipv4.sysctl_tcp_wmem[2]);

}



/* 2. Tuning advertised window (window_clamp, rcv_ssthresh)
@@ -354,7 +354,7 @@ static int __tcp_grow_window(const struct sock *sk, const struct sk_buff *skb) 
	struct tcp_sock *tp = tcp_sk(sk);

	/* Optimize this! */

	int truesize = tcp_win_from_space(sk, skb->truesize) >> 1;

	int window = tcp_win_from_space(sk, sysctl_tcp_rmem[2]) >> 1;

	int window = tcp_win_from_space(sk, sock_net(sk)->ipv4.sysctl_tcp_rmem[2]) >> 1;



	while (tp->rcv_ssthresh <= window) {

		if (truesize <= skb->len)
@@ -409,7 +409,7 @@ static void tcp_fixup_rcvbuf(struct sock *sk) 
		rcvmem <<= 2;



	if (sk->sk_rcvbuf < rcvmem)

		sk->sk_rcvbuf = min(rcvmem, sysctl_tcp_rmem[2]);

		sk->sk_rcvbuf = min(rcvmem, sock_net(sk)->ipv4.sysctl_tcp_rmem[2]);

}



/* 4. Try to fixup all. It is made immediately after connection enters
@@ -457,15 +457,16 @@ static void tcp_clamp_window(struct sock *sk) 
{

	struct tcp_sock *tp = tcp_sk(sk);

	struct inet_connection_sock *icsk = inet_csk(sk);

	struct net *net = sock_net(sk);



	icsk->icsk_ack.quick = 0;



	if (sk->sk_rcvbuf < sysctl_tcp_rmem[2] &&

	if (sk->sk_rcvbuf < net->ipv4.sysctl_tcp_rmem[2] &&

	    !(sk->sk_userlocks & SOCK_RCVBUF_LOCK) &&

	    !tcp_under_memory_pressure(sk) &&

	    sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)) {

		sk->sk_rcvbuf = min(atomic_read(&sk->sk_rmem_alloc),

				    sysctl_tcp_rmem[2]);

				    net->ipv4.sysctl_tcp_rmem[2]);

	}

	if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf)

		tp->rcv_ssthresh = min(tp->window_clamp, 2U * tp->advmss);
@@ -623,7 +624,8 @@ void tcp_rcv_space_adjust(struct sock *sk) 
		while (tcp_win_from_space(sk, rcvmem) < tp->advmss)

			rcvmem += 128;



		rcvbuf = min(rcvwin / tp->advmss * rcvmem, sysctl_tcp_rmem[2]);

		rcvbuf = min(rcvwin / tp->advmss * rcvmem,

			     sock_net(sk)->ipv4.sysctl_tcp_rmem[2]);

		if (rcvbuf > sk->sk_rcvbuf) {

			sk->sk_rcvbuf = rcvbuf;

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