cregit-Linux how code gets into the kernel

Release 4.8 net/dccp/timer.c

Directory: net/dccp
 *  net/dccp/timer.c
 *  An implementation of the DCCP protocol
 *  Arnaldo Carvalho de Melo <>
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.

#include <linux/dccp.h>
#include <linux/skbuff.h>
#include <linux/export.h>

#include "dccp.h"

/* sysctl variables governing numbers of retransmission attempts */

int  sysctl_dccp_request_retries	__read_mostly = TCP_SYN_RETRIES;

int  sysctl_dccp_retries1		__read_mostly = TCP_RETR1;

int  sysctl_dccp_retries2		__read_mostly = TCP_RETR2;

static void dccp_write_err(struct sock *sk) { sk->sk_err = sk->sk_err_soft ? : ETIMEDOUT; sk->sk_error_report(sk); dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED); dccp_done(sk); __DCCP_INC_STATS(DCCP_MIB_ABORTONTIMEOUT); }


arnaldo carvalho de meloarnaldo carvalho de melo4597.83%266.67%
eric dumazeteric dumazet12.17%133.33%

/* A write timeout has occurred. Process the after effects. */
static int dccp_write_timeout(struct sock *sk) { const struct inet_connection_sock *icsk = inet_csk(sk); int retry_until; if (sk->sk_state == DCCP_REQUESTING || sk->sk_state == DCCP_PARTOPEN) { if (icsk->icsk_retransmits != 0) dst_negative_advice(sk); retry_until = icsk->icsk_syn_retries ? : sysctl_dccp_request_retries; } else { if (icsk->icsk_retransmits >= sysctl_dccp_retries1) { /* NOTE. draft-ietf-tcpimpl-pmtud-01.txt requires pmtu black hole detection. :-( It is place to make it. It is not made. I do not want to make it. It is disguisting. It does not work in any case. Let me to cite the same draft, which requires for us to implement this: "The one security concern raised by this memo is that ICMP black holes are often caused by over-zealous security administrators who block all ICMP messages. It is vitally important that those who design and deploy security systems understand the impact of strict filtering on upper-layer protocols. The safest web site in the world is worthless if most TCP implementations cannot transfer data from it. It would be far nicer to have all of the black holes fixed rather than fixing all of the TCP implementations." Golden words :-). */ dst_negative_advice(sk); } retry_until = sysctl_dccp_retries2; /* * FIXME: see tcp_write_timout and tcp_out_of_resources */ } if (icsk->icsk_retransmits >= retry_until) { /* Has it gone just too far? */ dccp_write_err(sk); return 1; } return 0; }


arnaldo carvalho de meloarnaldo carvalho de melo10394.50%125.00%
gerrit renkergerrit renker32.75%125.00%
krishna kumarkrishna kumar21.83%125.00%
hideaki yoshifujihideaki yoshifuji10.92%125.00%

/* * The DCCP retransmit timer. */
static void dccp_retransmit_timer(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); /* * More than than 4MSL (8 minutes) has passed, a RESET(aborted) was * sent, no need to retransmit, this sock is dead. */ if (dccp_write_timeout(sk)) return; /* * We want to know the number of packets retransmitted, not the * total number of retransmissions of clones of original packets. */ if (icsk->icsk_retransmits == 0) __DCCP_INC_STATS(DCCP_MIB_TIMEOUTS); if (dccp_retransmit_skb(sk) != 0) { /* * Retransmission failed because of local congestion, * do not backoff. */ if (--icsk->icsk_retransmits == 0) icsk->icsk_retransmits = 1; inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, min(icsk->icsk_rto, TCP_RESOURCE_PROBE_INTERVAL), DCCP_RTO_MAX); return; } icsk->icsk_backoff++; icsk->icsk_rto = min(icsk->icsk_rto << 1, DCCP_RTO_MAX); inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, icsk->icsk_rto, DCCP_RTO_MAX); if (icsk->icsk_retransmits > sysctl_dccp_retries1) __sk_dst_reset(sk); }


arnaldo carvalho de meloarnaldo carvalho de melo6950.74%233.33%
gerrit renkergerrit renker6648.53%350.00%
eric dumazeteric dumazet10.74%116.67%

static void dccp_write_timer(unsigned long data) { struct sock *sk = (struct sock *)data; struct inet_connection_sock *icsk = inet_csk(sk); int event = 0; bh_lock_sock(sk); if (sock_owned_by_user(sk)) { /* Try again later */ sk_reset_timer(sk, &icsk->icsk_retransmit_timer, jiffies + (HZ / 20)); goto out; } if (sk->sk_state == DCCP_CLOSED || !icsk->icsk_pending) goto out; if (time_after(icsk->icsk_timeout, jiffies)) { sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout); goto out; } event = icsk->icsk_pending; icsk->icsk_pending = 0; switch (event) { case ICSK_TIME_RETRANS: dccp_retransmit_timer(sk); break; } out: bh_unlock_sock(sk); sock_put(sk); }


arnaldo carvalho de meloarnaldo carvalho de melo158100.00%1100.00%

static void dccp_keepalive_timer(unsigned long data) { struct sock *sk = (struct sock *)data; pr_err("dccp should not use a keepalive timer !\n"); sock_put(sk); }


arnaldo carvalho de meloarnaldo carvalho de melo3093.75%150.00%
eric dumazeteric dumazet26.25%150.00%

/* This is the same as tcp_delack_timer, sans prequeue & mem_reclaim stuff */
static void dccp_delack_timer(unsigned long data) { struct sock *sk = (struct sock *)data; struct inet_connection_sock *icsk = inet_csk(sk); bh_lock_sock(sk); if (sock_owned_by_user(sk)) { /* Try again later. */ icsk->icsk_ack.blocked = 1; __NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOCKED); sk_reset_timer(sk, &icsk->icsk_delack_timer, jiffies + TCP_DELACK_MIN); goto out; } if (sk->sk_state == DCCP_CLOSED || !(icsk->icsk_ack.pending & ICSK_ACK_TIMER)) goto out; if (time_after(icsk->icsk_ack.timeout, jiffies)) { sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout); goto out; } icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER; if (inet_csk_ack_scheduled(sk)) { if (!icsk->icsk_ack.pingpong) { /* Delayed ACK missed: inflate ATO. */ icsk->icsk_ack.ato = min(icsk->icsk_ack.ato << 1, icsk->icsk_rto); } else { /* Delayed ACK missed: leave pingpong mode and * deflate ATO. */ icsk->icsk_ack.pingpong = 0; icsk->icsk_ack.ato = TCP_ATO_MIN; } dccp_send_ack(sk); __NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKS); } out: bh_unlock_sock(sk); sock_put(sk); }


gerrit renkergerrit renker22494.92%133.33%
pavel emelianovpavel emelianov104.24%133.33%
eric dumazeteric dumazet20.85%133.33%

/** * dccp_write_xmitlet - Workhorse for CCID packet dequeueing interface * See the comments above %ccid_dequeueing_decision for supported modes. */
static void dccp_write_xmitlet(unsigned long data) { struct sock *sk = (struct sock *)data; bh_lock_sock(sk); if (sock_owned_by_user(sk)) sk_reset_timer(sk, &dccp_sk(sk)->dccps_xmit_timer, jiffies + 1); else dccp_write_xmit(sk); bh_unlock_sock(sk); }


gerrit renkergerrit renker6198.39%266.67%
adrian bunkadrian bunk11.61%133.33%

static void dccp_write_xmit_timer(unsigned long data) { dccp_write_xmitlet(data); sock_put((struct sock *)data); }


gerrit renkergerrit renker25100.00%2100.00%

void dccp_init_xmit_timers(struct sock *sk) { struct dccp_sock *dp = dccp_sk(sk); tasklet_init(&dp->dccps_xmitlet, dccp_write_xmitlet, (unsigned long)sk); setup_timer(&dp->dccps_xmit_timer, dccp_write_xmit_timer, (unsigned long)sk); inet_csk_init_xmit_timers(sk, &dccp_write_timer, &dccp_delack_timer, &dccp_keepalive_timer); }


gerrit renkergerrit renker6395.45%375.00%
pavel emelianovpavel emelianov34.55%125.00%

static ktime_t dccp_timestamp_seed; /** * dccp_timestamp - 10s of microseconds time source * Returns the number of 10s of microseconds since loading DCCP. This is native * DCCP time difference format (RFC 4340, sec. 13). * Please note: This will wrap around about circa every 11.9 hours. */
u32 dccp_timestamp(void) { u64 delta = (u64)ktime_us_delta(ktime_get_real(), dccp_timestamp_seed); do_div(delta, 10); return delta; }


gerrit renkergerrit renker2787.10%150.00%
chen gangchen gang412.90%150.00%

void __init dccp_timestamping_init(void) { dccp_timestamp_seed = ktime_get_real(); }


gerrit renkergerrit renker13100.00%1100.00%

Overall Contributors

gerrit renkergerrit renker51453.54%631.58%
arnaldo carvalho de meloarnaldo carvalho de melo41643.33%315.79%
pavel emelianovpavel emelianov131.35%210.53%
eric dumazeteric dumazet60.62%315.79%
chen gangchen gang40.42%15.26%
paul gortmakerpaul gortmaker30.31%15.26%
krishna kumarkrishna kumar20.21%15.26%
hideaki yoshifujihideaki yoshifuji10.10%15.26%
adrian bunkadrian bunk10.10%15.26%
Directory: net/dccp
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.