diff options
Diffstat (limited to 'net/ipv4/tcp.c')
-rw-r--r-- | net/ipv4/tcp.c | 31 |
1 files changed, 25 insertions, 6 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 87981fcdfcf2..cc8fd8b747a4 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -320,17 +320,36 @@ struct tcp_splice_state { * All the __sk_mem_schedule() is of this nature: accounting * is strict, actions are advisory and have some latency. */ -int tcp_memory_pressure __read_mostly; -EXPORT_SYMBOL(tcp_memory_pressure); +unsigned long tcp_memory_pressure __read_mostly; +EXPORT_SYMBOL_GPL(tcp_memory_pressure); void tcp_enter_memory_pressure(struct sock *sk) { - if (!tcp_memory_pressure) { + unsigned long val; + + if (tcp_memory_pressure) + return; + val = jiffies; + + if (!val) + val--; + if (!cmpxchg(&tcp_memory_pressure, 0, val)) NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMEMORYPRESSURES); - tcp_memory_pressure = 1; - } } -EXPORT_SYMBOL(tcp_enter_memory_pressure); +EXPORT_SYMBOL_GPL(tcp_enter_memory_pressure); + +void tcp_leave_memory_pressure(struct sock *sk) +{ + unsigned long val; + + if (!tcp_memory_pressure) + return; + val = xchg(&tcp_memory_pressure, 0); + if (val) + NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPMEMORYPRESSURESCHRONO, + jiffies_to_msecs(jiffies - val)); +} +EXPORT_SYMBOL_GPL(tcp_leave_memory_pressure); /* Convert seconds to retransmits based on initial and max timeout */ static u8 secs_to_retrans(int seconds, int timeout, int rto_max) |