tcp_timer.c: Add kernel-doc function descriptions
This adds kernel-doc style descriptions for 6 functions and fixes 1 typo. Signed-off-by: Richard Sailer <richard@weltraumpflege.org> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Родитель
7dc0993452
Коммит
c380d37e97
|
@ -24,6 +24,13 @@
|
|||
|
||||
int sysctl_tcp_thin_linear_timeouts __read_mostly;
|
||||
|
||||
/**
|
||||
* tcp_write_err() - close socket and save error info
|
||||
* @sk: The socket the error has appeared on.
|
||||
*
|
||||
* Returns: Nothing (void)
|
||||
*/
|
||||
|
||||
static void tcp_write_err(struct sock *sk)
|
||||
{
|
||||
sk->sk_err = sk->sk_err_soft ? : ETIMEDOUT;
|
||||
|
@ -33,16 +40,21 @@ static void tcp_write_err(struct sock *sk)
|
|||
__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONTIMEOUT);
|
||||
}
|
||||
|
||||
/* Do not allow orphaned sockets to eat all our resources.
|
||||
* This is direct violation of TCP specs, but it is required
|
||||
* to prevent DoS attacks. It is called when a retransmission timeout
|
||||
* or zero probe timeout occurs on orphaned socket.
|
||||
/**
|
||||
* tcp_out_of_resources() - Close socket if out of resources
|
||||
* @sk: pointer to current socket
|
||||
* @do_reset: send a last packet with reset flag
|
||||
*
|
||||
* Criteria is still not confirmed experimentally and may change.
|
||||
* We kill the socket, if:
|
||||
* 1. If number of orphaned sockets exceeds an administratively configured
|
||||
* limit.
|
||||
* 2. If we have strong memory pressure.
|
||||
* Do not allow orphaned sockets to eat all our resources.
|
||||
* This is direct violation of TCP specs, but it is required
|
||||
* to prevent DoS attacks. It is called when a retransmission timeout
|
||||
* or zero probe timeout occurs on orphaned socket.
|
||||
*
|
||||
* Criteria is still not confirmed experimentally and may change.
|
||||
* We kill the socket, if:
|
||||
* 1. If number of orphaned sockets exceeds an administratively configured
|
||||
* limit.
|
||||
* 2. If we have strong memory pressure.
|
||||
*/
|
||||
static int tcp_out_of_resources(struct sock *sk, bool do_reset)
|
||||
{
|
||||
|
@ -74,7 +86,11 @@ static int tcp_out_of_resources(struct sock *sk, bool do_reset)
|
|||
return 0;
|
||||
}
|
||||
|
||||
/* Calculate maximal number or retries on an orphaned socket. */
|
||||
/**
|
||||
* tcp_orphan_retries() - Returns maximal number of retries on an orphaned socket
|
||||
* @sk: Pointer to the current socket.
|
||||
* @alive: bool, socket alive state
|
||||
*/
|
||||
static int tcp_orphan_retries(struct sock *sk, bool alive)
|
||||
{
|
||||
int retries = sock_net(sk)->ipv4.sysctl_tcp_orphan_retries; /* May be zero. */
|
||||
|
@ -115,10 +131,22 @@ static void tcp_mtu_probing(struct inet_connection_sock *icsk, struct sock *sk)
|
|||
}
|
||||
}
|
||||
|
||||
/* This function calculates a "timeout" which is equivalent to the timeout of a
|
||||
* TCP connection after "boundary" unsuccessful, exponentially backed-off
|
||||
|
||||
/**
|
||||
* retransmits_timed_out() - returns true if this connection has timed out
|
||||
* @sk: The current socket
|
||||
* @boundary: max number of retransmissions
|
||||
* @timeout: A custom timeout value.
|
||||
* If set to 0 the default timeout is calculated and used.
|
||||
* Using TCP_RTO_MIN and the number of unsuccessful retransmits.
|
||||
* @syn_set: true if the SYN Bit was set.
|
||||
*
|
||||
* The default "timeout" value this function can calculate and use
|
||||
* is equivalent to the timeout of a TCP Connection
|
||||
* after "boundary" unsuccessful, exponentially backed-off
|
||||
* retransmissions with an initial RTO of TCP_RTO_MIN or TCP_TIMEOUT_INIT if
|
||||
* syn_set flag is set.
|
||||
*
|
||||
*/
|
||||
static bool retransmits_timed_out(struct sock *sk,
|
||||
unsigned int boundary,
|
||||
|
@ -257,6 +285,16 @@ out:
|
|||
sk_mem_reclaim(sk);
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* tcp_delack_timer() - The TCP delayed ACK timeout handler
|
||||
* @data: Pointer to the current socket. (gets casted to struct sock *)
|
||||
*
|
||||
* This function gets (indirectly) called when the kernel timer for a TCP packet
|
||||
* of this socket expires. Calls tcp_delack_timer_handler() to do the actual work.
|
||||
*
|
||||
* Returns: Nothing (void)
|
||||
*/
|
||||
static void tcp_delack_timer(unsigned long data)
|
||||
{
|
||||
struct sock *sk = (struct sock *)data;
|
||||
|
@ -350,10 +388,18 @@ static void tcp_fastopen_synack_timer(struct sock *sk)
|
|||
TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX);
|
||||
}
|
||||
|
||||
/*
|
||||
* The TCP retransmit timer.
|
||||
*/
|
||||
|
||||
/**
|
||||
* tcp_retransmit_timer() - The TCP retransmit timeout handler
|
||||
* @sk: Pointer to the current socket.
|
||||
*
|
||||
* This function gets called when the kernel timer for a TCP packet
|
||||
* of this socket expires.
|
||||
*
|
||||
* It handles retransmission, timer adjustment and other necesarry measures.
|
||||
*
|
||||
* Returns: Nothing (void)
|
||||
*/
|
||||
void tcp_retransmit_timer(struct sock *sk)
|
||||
{
|
||||
struct tcp_sock *tp = tcp_sk(sk);
|
||||
|
@ -494,7 +540,8 @@ out_reset_timer:
|
|||
out:;
|
||||
}
|
||||
|
||||
/* Called with BH disabled */
|
||||
/* Called with bottom-half processing disabled.
|
||||
Called by tcp_write_timer() */
|
||||
void tcp_write_timer_handler(struct sock *sk)
|
||||
{
|
||||
struct inet_connection_sock *icsk = inet_csk(sk);
|
||||
|
@ -539,7 +586,7 @@ static void tcp_write_timer(unsigned long data)
|
|||
if (!sock_owned_by_user(sk)) {
|
||||
tcp_write_timer_handler(sk);
|
||||
} else {
|
||||
/* deleguate our work to tcp_release_cb() */
|
||||
/* delegate our work to tcp_release_cb() */
|
||||
if (!test_and_set_bit(TCP_WRITE_TIMER_DEFERRED, &tcp_sk(sk)->tsq_flags))
|
||||
sock_hold(sk);
|
||||
}
|
||||
|
|
Загрузка…
Ссылка в новой задаче