1 | #include <net/tcp.h> |
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2 | #include <linux/module.h> |
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3 | |
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4 | static void exp_slow_start(struct tcp_sock *tp) |
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5 | { |
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6 | /* Handle cwnd manipulation for slow start here */ |
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7 | } |
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8 | |
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9 | static void exp_cong_avoid(struct sock *sk, u32 adk, u32 in_flight) |
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10 | { |
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11 | /* Handle cwnd manipulation for congestion avoidance here */ |
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12 | } |
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13 | |
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14 | static u32 exp_ssthresh(struct sock *sk) |
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15 | { |
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16 | /* Compute the appropriate value of ssthresh here */ |
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17 | } |
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18 | |
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19 | |
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20 | //See http://lwn.net/Articles/128681/ for more information |
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21 | /* |
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22 | * The start() method initializes the algorithm when a new batch of data |
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23 | * is being transmitted; this can happen for new sockets, or when one |
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24 | * has been idle for a while. |
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25 | * |
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26 | * The ssthresh() method calculates the "slow start threshold"; when the |
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27 | * congestion window is below that threshold, the connection is in slow |
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28 | * start mode rather than full congestion avoidance mode. This method is |
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29 | * called when congestion occurs. |
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30 | * |
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31 | * The actual initial window may be set by min_cwnd() to be less than |
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32 | * the threshold value as a starting point for the slow start algorithm. |
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33 | * |
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34 | * When an acknowledgment arrives from the remote end, the cong_avoid() |
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35 | * method is invoked; it may respond to successful packet delivery by |
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36 | * enlarging the congestion window. |
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37 | * |
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38 | * rtt_sample() tells the algorithm about a measured round-trip time - |
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39 | * the time taken between sending a packet and receiving the |
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40 | * corresponding acknowledgment. |
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41 | * |
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42 | * set_state() indicates that the TCP state of the socket has changed. |
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43 | * |
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44 | * Various events of interest can be communicated to the algorithm via |
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45 | * cwnd_event(). |
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46 | * |
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47 | * Sometimes, transient situations can cause the congestion window to be |
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48 | * reduced; the undo_cwnd() method can be called when such a situation |
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49 | * is detected to restore a larger window. |
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50 | * |
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51 | * The get_info() method can be used to make congestion avoidance |
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52 | * information available to user space. |
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53 | */ |
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54 | static struct tcp_congestion_ops tcp_exp __read_mostly = { |
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55 | .init = NULL, |
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56 | .ssthresh = exp_ssthresh, |
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57 | .cong_avoid = exp_cong_avoid, |
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58 | .min_cwnd = tcp_reno_min_cwnd, |
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59 | |
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60 | .owner = THIS_MODULE, |
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61 | .name = "exp" |
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62 | }; |
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63 | |
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64 | static int __init exp_register(void) |
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65 | { |
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66 | return tcp_register_congestion_control(&tcp_exp); |
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67 | } |
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68 | |
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69 | static void __exit exp_unregister(void) |
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70 | { |
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71 | tcp_unregister_congestion_control(&tcp_exp); |
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72 | } |
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73 | |
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74 | module_init(exp_register); |
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75 | module_exit(exp_unregister); |
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76 | |
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77 | MODULE_AUTHOR("Your Name Here"); |
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78 | MODULE_LICENSE("GPL"); |
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79 | MODULE_DESCRIPTION("Experimental TCP"); |
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