patch-2.4.27 linux-2.4.27/net/sched/sch_netem.c

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diff -urN linux-2.4.26/net/sched/sch_netem.c linux-2.4.27/net/sched/sch_netem.c
@@ -0,0 +1,961 @@
+/*
+ * net/sched/sch_netem.c	Network emulator
+ *
+ * 		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.
+ *
+ * Authors:	Stephen Hemminger <shemminger@osdl.org>
+ *		Catalin(ux aka Dino) BOIE <catab at umbrella dot ro>
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <asm/bitops.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+
+#include <net/pkt_sched.h>
+
+/*	Network emulator
+ *
+ *	This scheduler can alters spacing and order
+ *	Similar to NISTnet and BSD Dummynet.
+ */
+
+struct netem_sched_data {
+	struct Qdisc	*qdisc;
+	struct sk_buff_head delayed;
+	struct timer_list timer;
+
+	u32 latency;
+	u32 loss;
+	u32 limit;
+	u32 counter;
+	u32 gap;
+	u32 jitter;
+};
+
+/* Time stamp put into socket buffer control block */
+struct netem_skb_cb {
+	psched_time_t	time_to_send;
+};
+
+/* This is the distribution table for the normal distribution produced
+ * with NISTnet tools.
+ * The entries represent a scaled inverse of the cumulative distribution
+ * function.
+ */
+#define TABLESIZE	2048
+#define TABLEFACTOR	8192
+
+static const short disttable[TABLESIZE] = {
+	-31473,		-26739,		-25226,		-24269,
+	-23560,		-22993,		-22518,		-22109,
+	-21749,		-21426,		-21133,		-20865,
+	-20618,		-20389,		-20174,		-19972,
+	-19782,		-19601,		-19430,		-19267,
+	-19112,		-18962,		-18819,		-18681,
+	-18549,		-18421,		-18298,		-18178,
+	-18062,		-17950,		-17841,		-17735,
+	-17632,		-17532,		-17434,		-17339,
+	-17245,		-17155,		-17066,		-16979,
+	-16894,		-16811,		-16729,		-16649,
+	-16571,		-16494,		-16419,		-16345,
+	-16272,		-16201,		-16130,		-16061,
+	-15993,		-15926,		-15861,		-15796,
+	-15732,		-15669,		-15607,		-15546,
+	-15486,		-15426,		-15368,		-15310,
+	-15253,		-15196,		-15140,		-15086,
+	-15031,		-14977,		-14925,		-14872,
+	-14821,		-14769,		-14719,		-14669,
+	-14619,		-14570,		-14522,		-14473,
+	-14426,		-14379,		-14332,		-14286,
+	-14241,		-14196,		-14150,		-14106,
+	-14062,		-14019,		-13976,		-13933,
+	-13890,		-13848,		-13807,		-13765,
+	-13724,		-13684,		-13643,		-13604,
+	-13564,		-13525,		-13486,		-13447,
+	-13408,		-13370,		-13332,		-13295,
+	-13258,		-13221,		-13184,		-13147,
+	-13111,		-13075,		-13040,		-13004,
+	-12969,		-12934,		-12899,		-12865,
+	-12830,		-12796,		-12762,		-12729,
+	-12695,		-12662,		-12629,		-12596,
+	-12564,		-12531,		-12499,		-12467,
+	-12435,		-12404,		-12372,		-12341,
+	-12310,		-12279,		-12248,		-12218,
+	-12187,		-12157,		-12127,		-12097,
+	-12067,		-12038,		-12008,		-11979,
+	-11950,		-11921,		-11892,		-11863,
+	-11835,		-11806,		-11778,		-11750,
+	-11722,		-11694,		-11666,		-11639,
+	-11611,		-11584,		-11557,		-11530,
+	-11503,		-11476,		-11450,		-11423,
+	-11396,		-11370,		-11344,		-11318,
+	-11292,		-11266,		-11240,		-11214,
+	-11189,		-11164,		-11138,		-11113,
+	-11088,		-11063,		-11038,		-11013,
+	-10988,		-10964,		-10939,		-10915,
+	-10891,		-10866,		-10843,		-10818,
+	-10794,		-10770,		-10747,		-10723,
+	-10700,		-10676,		-10652,		-10630,
+	-10606,		-10583,		-10560,		-10537,
+	-10514,		-10491,		-10469,		-10446,
+	-10424,		-10401,		-10378,		-10356,
+	-10334,		-10312,		-10290,		-10267,
+	-10246,		-10224,		-10202,		-10180,
+	-10158,		-10137,		-10115,		-10094,
+	-10072,		-10051,		-10030,		-10009,
+	-9988,		-9967,		-9945,		-9925,
+	-9904,		-9883,		-9862,		-9842,
+	-9821,		-9800,		-9780,		-9760,
+	-9739,		-9719,		-9699,		-9678,
+	-9658,		-9638,		-9618,		-9599,
+	-9578,		-9559,		-9539,		-9519,
+	-9499,		-9480,		-9461,		-9441,
+	-9422,		-9402,		-9383,		-9363,
+	-9344,		-9325,		-9306,		-9287,
+	-9268,		-9249,		-9230,		-9211,
+	-9192,		-9173,		-9155,		-9136,
+	-9117,		-9098,		-9080,		-9062,
+	-9043,		-9025,		-9006,		-8988,
+	-8970,		-8951,		-8933,		-8915,
+	-8897,		-8879,		-8861,		-8843,
+	-8825,		-8807,		-8789,		-8772,
+	-8754,		-8736,		-8718,		-8701,
+	-8683,		-8665,		-8648,		-8630,
+	-8613,		-8595,		-8578,		-8561,
+	-8543,		-8526,		-8509,		-8492,
+	-8475,		-8458,		-8441,		-8423,
+	-8407,		-8390,		-8373,		-8356,
+	-8339,		-8322,		-8305,		-8289,
+	-8272,		-8255,		-8239,		-8222,
+	-8206,		-8189,		-8172,		-8156,
+	-8140,		-8123,		-8107,		-8090,
+	-8074,		-8058,		-8042,		-8025,
+	-8009,		-7993,		-7977,		-7961,
+	-7945,		-7929,		-7913,		-7897,
+	-7881,		-7865,		-7849,		-7833,
+	-7817,		-7802,		-7786,		-7770,
+	-7754,		-7739,		-7723,		-7707,
+	-7692,		-7676,		-7661,		-7645,
+	-7630,		-7614,		-7599,		-7583,
+	-7568,		-7553,		-7537,		-7522,
+	-7507,		-7492,		-7476,		-7461,
+	-7446,		-7431,		-7416,		-7401,
+	-7385,		-7370,		-7356,		-7340,
+	-7325,		-7311,		-7296,		-7281,
+	-7266,		-7251,		-7236,		-7221,
+	-7207,		-7192,		-7177,		-7162,
+	-7148,		-7133,		-7118,		-7104,
+	-7089,		-7075,		-7060,		-7046,
+	-7031,		-7016,		-7002,		-6988,
+	-6973,		-6959,		-6944,		-6930,
+	-6916,		-6901,		-6887,		-6873,
+	-6859,		-6844,		-6830,		-6816,
+	-6802,		-6788,		-6774,		-6760,
+	-6746,		-6731,		-6717,		-6704,
+	-6690,		-6675,		-6661,		-6647,
+	-6633,		-6620,		-6606,		-6592,
+	-6578,		-6564,		-6550,		-6537,
+	-6523,		-6509,		-6495,		-6482,
+	-6468,		-6454,		-6441,		-6427,
+	-6413,		-6400,		-6386,		-6373,
+	-6359,		-6346,		-6332,		-6318,
+	-6305,		-6291,		-6278,		-6264,
+	-6251,		-6238,		-6224,		-6211,
+	-6198,		-6184,		-6171,		-6158,
+	-6144,		-6131,		-6118,		-6105,
+	-6091,		-6078,		-6065,		-6052,
+	-6039,		-6025,		-6012,		-5999,
+	-5986,		-5973,		-5960,		-5947,
+	-5934,		-5921,		-5908,		-5895,
+	-5882,		-5869,		-5856,		-5843,
+	-5830,		-5817,		-5804,		-5791,
+	-5779,		-5766,		-5753,		-5740,
+	-5727,		-5714,		-5702,		-5689,
+	-5676,		-5663,		-5650,		-5638,
+	-5625,		-5612,		-5600,		-5587,
+	-5575,		-5562,		-5549,		-5537,
+	-5524,		-5512,		-5499,		-5486,
+	-5474,		-5461,		-5449,		-5436,
+	-5424,		-5411,		-5399,		-5386,
+	-5374,		-5362,		-5349,		-5337,
+	-5324,		-5312,		-5299,		-5287,
+	-5275,		-5263,		-5250,		-5238,
+	-5226,		-5213,		-5201,		-5189,
+	-5177,		-5164,		-5152,		-5140,
+	-5128,		-5115,		-5103,		-5091,
+	-5079,		-5067,		-5055,		-5043,
+	-5030,		-5018,		-5006,		-4994,
+	-4982,		-4970,		-4958,		-4946,
+	-4934,		-4922,		-4910,		-4898,
+	-4886,		-4874,		-4862,		-4850,
+	-4838,		-4826,		-4814,		-4803,
+	-4791,		-4778,		-4767,		-4755,
+	-4743,		-4731,		-4719,		-4708,
+	-4696,		-4684,		-4672,		-4660,
+	-4649,		-4637,		-4625,		-4613,
+	-4601,		-4590,		-4578,		-4566,
+	-4554,		-4543,		-4531,		-4520,
+	-4508,		-4496,		-4484,		-4473,
+	-4461,		-4449,		-4438,		-4427,
+	-4415,		-4403,		-4392,		-4380,
+	-4368,		-4357,		-4345,		-4334,
+	-4322,		-4311,		-4299,		-4288,
+	-4276,		-4265,		-4253,		-4242,
+	-4230,		-4219,		-4207,		-4196,
+	-4184,		-4173,		-4162,		-4150,
+	-4139,		-4128,		-4116,		-4105,
+	-4094,		-4082,		-4071,		-4060,
+	-4048,		-4037,		-4026,		-4014,
+	-4003,		-3992,		-3980,		-3969,
+	-3958,		-3946,		-3935,		-3924,
+	-3913,		-3901,		-3890,		-3879,
+	-3868,		-3857,		-3845,		-3834,
+	-3823,		-3812,		-3801,		-3790,
+	-3779,		-3767,		-3756,		-3745,
+	-3734,		-3723,		-3712,		-3700,
+	-3689,		-3678,		-3667,		-3656,
+	-3645,		-3634,		-3623,		-3612,
+	-3601,		-3590,		-3579,		-3568,
+	-3557,		-3545,		-3535,		-3524,
+	-3513,		-3502,		-3491,		-3480,
+	-3469,		-3458,		-3447,		-3436,
+	-3425,		-3414,		-3403,		-3392,
+	-3381,		-3370,		-3360,		-3348,
+	-3337,		-3327,		-3316,		-3305,
+	-3294,		-3283,		-3272,		-3262,
+	-3251,		-3240,		-3229,		-3218,
+	-3207,		-3197,		-3185,		-3175,
+	-3164,		-3153,		-3142,		-3132,
+	-3121,		-3110,		-3099,		-3088,
+	-3078,		-3067,		-3056,		-3045,
+	-3035,		-3024,		-3013,		-3003,
+	-2992,		-2981,		-2970,		-2960,
+	-2949,		-2938,		-2928,		-2917,
+	-2906,		-2895,		-2885,		-2874,
+	-2864,		-2853,		-2842,		-2832,
+	-2821,		-2810,		-2800,		-2789,
+	-2778,		-2768,		-2757,		-2747,
+	-2736,		-2725,		-2715,		-2704,
+	-2694,		-2683,		-2673,		-2662,
+	-2651,		-2641,		-2630,		-2620,
+	-2609,		-2599,		-2588,		-2578,
+	-2567,		-2556,		-2546,		-2535,
+	-2525,		-2515,		-2504,		-2493,
+	-2483,		-2472,		-2462,		-2451,
+	-2441,		-2431,		-2420,		-2410,
+	-2399,		-2389,		-2378,		-2367,
+	-2357,		-2347,		-2336,		-2326,
+	-2315,		-2305,		-2295,		-2284,
+	-2274,		-2263,		-2253,		-2243,
+	-2232,		-2222,		-2211,		-2201,
+	-2191,		-2180,		-2170,		-2159,
+	-2149,		-2139,		-2128,		-2118,
+	-2107,		-2097,		-2087,		-2076,
+	-2066,		-2056,		-2046,		-2035,
+	-2025,		-2014,		-2004,		-1994,
+	-1983,		-1973,		-1963,		-1953,
+	-1942,		-1932,		-1921,		-1911,
+	-1901,		-1891,		-1880,		-1870,
+	-1860,		-1849,		-1839,		-1829,
+	-1819,		-1808,		-1798,		-1788,
+	-1778,		-1767,		-1757,		-1747,
+	-1736,		-1726,		-1716,		-1706,
+	-1695,		-1685,		-1675,		-1665,
+	-1654,		-1644,		-1634,		-1624,
+	-1613,		-1603,		-1593,		-1583,
+	-1573,		-1563,		-1552,		-1542,
+	-1532,		-1522,		-1511,		-1501,
+	-1491,		-1481,		-1471,		-1461,
+	-1450,		-1440,		-1430,		-1420,
+	-1409,		-1400,		-1389,		-1379,
+	-1369,		-1359,		-1348,		-1339,
+	-1328,		-1318,		-1308,		-1298,
+	-1288,		-1278,		-1267,		-1257,
+	-1247,		-1237,		-1227,		-1217,
+	-1207,		-1196,		-1186,		-1176,
+	-1166,		-1156,		-1146,		-1135,
+	-1126,		-1115,		-1105,		-1095,
+	-1085,		-1075,		-1065,		-1055,
+	-1044,		-1034,		-1024,		-1014,
+	-1004,		-994,		-984,		-974,
+	-964,		-954,		-944,		-933,
+	-923,		-913,		-903,		-893,
+	-883,		-873,		-863,		-853,
+	-843,		-833,		-822,		-812,
+	-802,		-792,		-782,		-772,
+	-762,		-752,		-742,		-732,
+	-722,		-712,		-702,		-691,
+	-682,		-671,		-662,		-651,
+	-641,		-631,		-621,		-611,
+	-601,		-591,		-581,		-571,
+	-561,		-551,		-541,		-531,
+	-521,		-511,		-501,		-491,
+	-480,		-471,		-460,		-451,
+	-440,		-430,		-420,		-410,
+	-400,		-390,		-380,		-370,
+	-360,		-350,		-340,		-330,
+	-320,		-310,		-300,		-290,
+	-280,		-270,		-260,		-250,
+	-240,		-230,		-220,		-210,
+	-199,		-190,		-179,		-170,
+	-159,		-150,		-139,		-129,
+	-119,		-109,		-99,		-89,
+	-79,		-69,		-59,		-49,
+	-39,		-29,		-19,		-9,
+	1,		11,		21,		31,
+	41,		51,		61,		71,
+	81,		91,		101,		111,
+	121,		131,		141,		152,
+	161,		172,		181,		192,
+	202,		212,		222,		232,
+	242,		252,		262,		272,
+	282,		292,		302,		312,
+	322,		332,		342,		352,
+	362,		372,		382,		392,
+	402,		412,		422,		433,
+	442,		453,		462,		473,
+	483,		493,		503,		513,
+	523,		533,		543,		553,
+	563,		573,		583,		593,
+	603,		613,		623,		633,
+	643,		653,		664,		673,
+	684,		694,		704,		714,
+	724,		734,		744,		754,
+	764,		774,		784,		794,
+	804,		815,		825,		835,
+	845,		855,		865,		875,
+	885,		895,		905,		915,
+	925,		936,		946,		956,
+	966,		976,		986,		996,
+	1006,		1016,		1026,		1037,
+	1047,		1057,		1067,		1077,
+	1087,		1097,		1107,		1117,
+	1128,		1138,		1148,		1158,
+	1168,		1178,		1188,		1198,
+	1209,		1219,		1229,		1239,
+	1249,		1259,		1269,		1280,
+	1290,		1300,		1310,		1320,
+	1330,		1341,		1351,		1361,
+	1371,		1381,		1391,		1402,
+	1412,		1422,		1432,		1442,
+	1452,		1463,		1473,		1483,
+	1493,		1503,		1513,		1524,
+	1534,		1544,		1554,		1565,
+	1575,		1585,		1595,		1606,
+	1616,		1626,		1636,		1647,
+	1656,		1667,		1677,		1687,
+	1697,		1708,		1718,		1729,
+	1739,		1749,		1759,		1769,
+	1780,		1790,		1800,		1810,
+	1821,		1831,		1841,		1851,
+	1862,		1872,		1883,		1893,
+	1903,		1913,		1923,		1934,
+	1944,		1955,		1965,		1975,
+	1985,		1996,		2006,		2016,
+	2027,		2037,		2048,		2058,
+	2068,		2079,		2089,		2099,
+	2110,		2120,		2130,		2141,
+	2151,		2161,		2172,		2182,
+	2193,		2203,		2213,		2224,
+	2234,		2245,		2255,		2265,
+	2276,		2286,		2297,		2307,
+	2318,		2328,		2338,		2349,
+	2359,		2370,		2380,		2391,
+	2401,		2412,		2422,		2433,
+	2443,		2454,		2464,		2475,
+	2485,		2496,		2506,		2517,
+	2527,		2537,		2548,		2559,
+	2569,		2580,		2590,		2601,
+	2612,		2622,		2632,		2643,
+	2654,		2664,		2675,		2685,
+	2696,		2707,		2717,		2728,
+	2738,		2749,		2759,		2770,
+	2781,		2791,		2802,		2813,
+	2823,		2834,		2845,		2855,
+	2866,		2877,		2887,		2898,
+	2909,		2919,		2930,		2941,
+	2951,		2962,		2973,		2984,
+	2994,		3005,		3015,		3027,
+	3037,		3048,		3058,		3069,
+	3080,		3091,		3101,		3113,
+	3123,		3134,		3145,		3156,
+	3166,		3177,		3188,		3199,
+	3210,		3220,		3231,		3242,
+	3253,		3264,		3275,		3285,
+	3296,		3307,		3318,		3329,
+	3340,		3351,		3362,		3373,
+	3384,		3394,		3405,		3416,
+	3427,		3438,		3449,		3460,
+	3471,		3482,		3493,		3504,
+	3515,		3526,		3537,		3548,
+	3559,		3570,		3581,		3592,
+	3603,		3614,		3625,		3636,
+	3647,		3659,		3670,		3681,
+	3692,		3703,		3714,		3725,
+	3736,		3747,		3758,		3770,
+	3781,		3792,		3803,		3814,
+	3825,		3837,		3848,		3859,
+	3870,		3881,		3893,		3904,
+	3915,		3926,		3937,		3949,
+	3960,		3971,		3983,		3994,
+	4005,		4017,		4028,		4039,
+	4051,		4062,		4073,		4085,
+	4096,		4107,		4119,		4130,
+	4141,		4153,		4164,		4175,
+	4187,		4198,		4210,		4221,
+	4233,		4244,		4256,		4267,
+	4279,		4290,		4302,		4313,
+	4325,		4336,		4348,		4359,
+	4371,		4382,		4394,		4406,
+	4417,		4429,		4440,		4452,
+	4464,		4475,		4487,		4499,
+	4510,		4522,		4533,		4545,
+	4557,		4569,		4581,		4592,
+	4604,		4616,		4627,		4639,
+	4651,		4663,		4674,		4686,
+	4698,		4710,		4722,		4734,
+	4746,		4758,		4769,		4781,
+	4793,		4805,		4817,		4829,
+	4841,		4853,		4865,		4877,
+	4889,		4900,		4913,		4925,
+	4936,		4949,		4961,		4973,
+	4985,		4997,		5009,		5021,
+	5033,		5045,		5057,		5070,
+	5081,		5094,		5106,		5118,
+	5130,		5143,		5155,		5167,
+	5179,		5191,		5204,		5216,
+	5228,		5240,		5253,		5265,
+	5278,		5290,		5302,		5315,
+	5327,		5340,		5352,		5364,
+	5377,		5389,		5401,		5414,
+	5426,		5439,		5451,		5464,
+	5476,		5489,		5502,		5514,
+	5527,		5539,		5552,		5564,
+	5577,		5590,		5603,		5615,
+	5628,		5641,		5653,		5666,
+	5679,		5691,		5704,		5717,
+	5730,		5743,		5756,		5768,
+	5781,		5794,		5807,		5820,
+	5833,		5846,		5859,		5872,
+	5885,		5897,		5911,		5924,
+	5937,		5950,		5963,		5976,
+	5989,		6002,		6015,		6028,
+	6042,		6055,		6068,		6081,
+	6094,		6108,		6121,		6134,
+	6147,		6160,		6174,		6187,
+	6201,		6214,		6227,		6241,
+	6254,		6267,		6281,		6294,
+	6308,		6321,		6335,		6348,
+	6362,		6375,		6389,		6403,
+	6416,		6430,		6443,		6457,
+	6471,		6485,		6498,		6512,
+	6526,		6540,		6554,		6567,
+	6581,		6595,		6609,		6623,
+	6637,		6651,		6665,		6679,
+	6692,		6706,		6721,		6735,
+	6749,		6763,		6777,		6791,
+	6805,		6819,		6833,		6848,
+	6862,		6876,		6890,		6905,
+	6919,		6933,		6948,		6962,
+	6976,		6991,		7005,		7020,
+	7034,		7049,		7064,		7078,
+	7093,		7107,		7122,		7136,
+	7151,		7166,		7180,		7195,
+	7210,		7225,		7240,		7254,
+	7269,		7284,		7299,		7314,
+	7329,		7344,		7359,		7374,
+	7389,		7404,		7419,		7434,
+	7449,		7465,		7480,		7495,
+	7510,		7526,		7541,		7556,
+	7571,		7587,		7602,		7618,
+	7633,		7648,		7664,		7680,
+	7695,		7711,		7726,		7742,
+	7758,		7773,		7789,		7805,
+	7821,		7836,		7852,		7868,
+	7884,		7900,		7916,		7932,
+	7948,		7964,		7981,		7997,
+	8013,		8029,		8045,		8061,
+	8078,		8094,		8110,		8127,
+	8143,		8160,		8176,		8193,
+	8209,		8226,		8242,		8259,
+	8276,		8292,		8309,		8326,
+	8343,		8360,		8377,		8394,
+	8410,		8428,		8444,		8462,
+	8479,		8496,		8513,		8530,
+	8548,		8565,		8582,		8600,
+	8617,		8634,		8652,		8670,
+	8687,		8704,		8722,		8740,
+	8758,		8775,		8793,		8811,
+	8829,		8847,		8865,		8883,
+	8901,		8919,		8937,		8955,
+	8974,		8992,		9010,		9029,
+	9047,		9066,		9084,		9103,
+	9121,		9140,		9159,		9177,
+	9196,		9215,		9234,		9253,
+	9272,		9291,		9310,		9329,
+	9349,		9368,		9387,		9406,
+	9426,		9445,		9465,		9484,
+	9504,		9524,		9544,		9563,
+	9583,		9603,		9623,		9643,
+	9663,		9683,		9703,		9723,
+	9744,		9764,		9785,		9805,
+	9826,		9846,		9867,		9888,
+	9909,		9930,		9950,		9971,
+	9993,		10013,		10035,		10056,
+	10077,		10099,		10120,		10142,
+	10163,		10185,		10207,		10229,
+	10251,		10273,		10294,		10317,
+	10339,		10361,		10384,		10406,
+	10428,		10451,		10474,		10496,
+	10519,		10542,		10565,		10588,
+	10612,		10635,		10658,		10682,
+	10705,		10729,		10752,		10776,
+	10800,		10824,		10848,		10872,
+	10896,		10921,		10945,		10969,
+	10994,		11019,		11044,		11069,
+	11094,		11119,		11144,		11169,
+	11195,		11221,		11246,		11272,
+	11298,		11324,		11350,		11376,
+	11402,		11429,		11456,		11482,
+	11509,		11536,		11563,		11590,
+	11618,		11645,		11673,		11701,
+	11728,		11756,		11785,		11813,
+	11842,		11870,		11899,		11928,
+	11957,		11986,		12015,		12045,
+	12074,		12104,		12134,		12164,
+	12194,		12225,		12255,		12286,
+	12317,		12348,		12380,		12411,
+	12443,		12475,		12507,		12539,
+	12571,		12604,		12637,		12670,
+	12703,		12737,		12771,		12804,
+	12839,		12873,		12907,		12942,
+	12977,		13013,		13048,		13084,
+	13120,		13156,		13192,		13229,
+	13267,		13304,		13341,		13379,
+	13418,		13456,		13495,		13534,
+	13573,		13613,		13653,		13693,
+	13734,		13775,		13817,		13858,
+	13901,		13943,		13986,		14029,
+	14073,		14117,		14162,		14206,
+	14252,		14297,		14343,		14390,
+	14437,		14485,		14533,		14582,
+	14631,		14680,		14731,		14782,
+	14833,		14885,		14937,		14991,
+	15044,		15099,		15154,		15210,
+	15266,		15324,		15382,		15441,
+	15500,		15561,		15622,		15684,
+	15747,		15811,		15877,		15943,
+	16010,		16078,		16148,		16218,
+	16290,		16363,		16437,		16513,
+	16590,		16669,		16749,		16831,
+	16915,		17000,		17088,		17177,
+	17268,		17362,		17458,		17556,
+	17657,		17761,		17868,		17977,
+	18090,		18207,		18328,		18452,
+	18581,		18715,		18854,		18998,
+	19149,		19307,		19472,		19645,
+	19828,		20021,		20226,		20444,
+	20678,		20930,		21204,		21503,
+	21835,		22206,		22630,		23124,
+	23721,		24478,		25529,		27316,
+};
+
+/* tabledist - return a pseudo-randomly distributed value with mean mu and
+ * std deviation sigma.  Uses table lookup to approximate the desired
+ * distribution, and a uniformly-distributed pseudo-random source.
+ */
+static inline int tabledist(int mu, int sigma)
+{
+	int x;
+	int index;
+	int sigmamod, sigmadiv;
+
+	if (sigma == 0)
+		return mu;
+
+	index = (net_random() & (TABLESIZE-1));
+	sigmamod = sigma%TABLEFACTOR;
+	sigmadiv = sigma/TABLEFACTOR;
+	x = sigmamod*disttable[index];
+
+	if (x >= 0)
+		x += TABLEFACTOR/2;
+	else
+		x -= TABLEFACTOR/2;
+
+	x /= TABLEFACTOR;
+	x += sigmadiv*disttable[index];
+	x += mu;
+	return x;
+}
+
+/* Enqueue packets with underlying discipline (fifo)
+ * but mark them with current time first.
+ */
+static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+	struct netem_skb_cb *cb = (struct netem_skb_cb *)skb->cb;
+	psched_time_t now;
+	long delay;
+
+	pr_debug("netem_enqueue skb=%p @%lu\n", skb, jiffies);
+
+	/* Random packet drop 0 => none, ~0 => all */
+	if (q->loss && q->loss >= net_random()) {
+		sch->stats.drops++;
+		return 0;	/* lie about loss so TCP doesn't know */
+	}
+
+
+	/* If doing simple delay then gap == 0 so all packets
+	 * go into the delayed holding queue
+	 * otherwise if doing out of order only "1 out of gap"
+	 * packets will be delayed.
+	 */
+	if (q->counter < q->gap) {
+		int ret;
+
+		++q->counter;
+		ret = q->qdisc->enqueue(skb, q->qdisc);
+		if (ret)
+			sch->stats.drops++;
+		return ret;
+	}
+	
+	q->counter = 0;
+	
+	PSCHED_GET_TIME(now);
+	if (q->jitter) 
+		delay = tabledist(q->latency, q->jitter);
+	else
+		delay = q->latency;
+
+	PSCHED_TADD2(now, delay, cb->time_to_send);
+	
+	/* Always queue at tail to keep packets in order */
+	if (likely(q->delayed.qlen < q->limit)) {
+		__skb_queue_tail(&q->delayed, skb);
+		sch->q.qlen++;
+		sch->stats.bytes += skb->len;
+		sch->stats.packets++;
+		return 0;
+	}
+
+	sch->stats.drops++;
+	kfree_skb(skb);
+	return NET_XMIT_DROP;
+}
+
+/* Requeue packets but don't change time stamp */
+static int netem_requeue(struct sk_buff *skb, struct Qdisc *sch)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+	int ret;
+
+	if ((ret = q->qdisc->ops->requeue(skb, q->qdisc)) == 0)
+		sch->q.qlen++;
+
+	return ret;
+}
+
+static unsigned int netem_drop(struct Qdisc* sch)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+	unsigned int len;
+
+	if ((len = q->qdisc->ops->drop(q->qdisc)) != 0) {
+		sch->q.qlen--;
+		sch->stats.drops++;
+	}
+	return len;
+}
+
+/* Dequeue packet.
+ *  Move all packets that are ready to send from the delay holding
+ *  list to the underlying qdisc, then just call dequeue
+ */
+static struct sk_buff *netem_dequeue(struct Qdisc *sch)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+	struct sk_buff *skb;
+	psched_time_t now;
+
+	PSCHED_GET_TIME(now);
+	while ((skb = skb_peek(&q->delayed)) != NULL) {
+		const struct netem_skb_cb *cb
+			= (const struct netem_skb_cb *)skb->cb;
+		long delay 
+			= PSCHED_US2JIFFIE(PSCHED_TDIFF(cb->time_to_send, now));
+		pr_debug("netem_dequeue: delay queue %p@%lu %ld\n",
+			 skb, jiffies, delay);
+
+		/* if more time remaining? */
+		if (delay > 0) {
+			mod_timer(&q->timer, jiffies + delay);
+			break;
+		}
+		__skb_unlink(skb, &q->delayed);
+
+		if (q->qdisc->enqueue(skb, q->qdisc))
+			sch->stats.drops++;
+	}
+
+	skb = q->qdisc->dequeue(q->qdisc);
+	if (skb) 
+		sch->q.qlen--;
+	return skb;
+}
+
+static void netem_watchdog(unsigned long arg)
+{
+	struct Qdisc *sch = (struct Qdisc *)arg;
+
+	pr_debug("netem_watchdog: fired @%lu\n", jiffies);
+	netif_schedule(sch->dev);
+}
+
+static void netem_reset(struct Qdisc *sch)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+
+	qdisc_reset(q->qdisc);
+	skb_queue_purge(&q->delayed);
+
+	sch->q.qlen = 0;
+	del_timer_sync(&q->timer);
+}
+
+static int set_fifo_limit(struct Qdisc *q, int limit)
+{
+        struct rtattr *rta;
+	int ret = -ENOMEM;
+
+	rta = kmalloc(RTA_LENGTH(sizeof(struct tc_fifo_qopt)), GFP_KERNEL);
+	if (rta) {
+		rta->rta_type = RTM_NEWQDISC;
+		rta->rta_len = RTA_LENGTH(sizeof(struct tc_fifo_qopt)); 
+		((struct tc_fifo_qopt *)RTA_DATA(rta))->limit = limit;
+		
+		ret = q->ops->change(q, rta);
+		kfree(rta);
+	}
+	return ret;
+}
+
+static int netem_change(struct Qdisc *sch, struct rtattr *opt)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+	struct tc_netem_qopt *qopt = RTA_DATA(opt);
+	struct Qdisc *child;
+	int ret;
+
+	if (opt->rta_len < RTA_LENGTH(sizeof(*qopt)))
+		return -EINVAL;
+
+	child = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops);
+	if (!child)
+		return -EINVAL;
+
+	ret = set_fifo_limit(child, qopt->limit);
+	if (ret) {
+		qdisc_destroy(child);
+		return ret;
+	}
+
+	sch_tree_lock(sch);
+	if (child) {
+		child = xchg(&q->qdisc, child);
+		if (child != &noop_qdisc)
+			qdisc_destroy(child);
+	
+		q->latency = qopt->latency;
+		q->jitter = qopt->jitter;
+		q->limit = qopt->limit;
+		q->gap = qopt->gap;
+		q->loss = qopt->loss;
+	}
+	sch_tree_unlock(sch);
+
+	return 0;
+}
+
+static int netem_init(struct Qdisc *sch, struct rtattr *opt)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+	int err;
+
+	if (!opt)
+		return -EINVAL;
+
+	MOD_INC_USE_COUNT;
+	skb_queue_head_init(&q->delayed);
+	q->qdisc = &noop_qdisc;
+
+	init_timer(&q->timer);
+	q->timer.function = netem_watchdog;
+	q->timer.data = (unsigned long) sch;
+	q->counter = 0;
+
+	err = netem_change(sch, opt);
+	if (err != 0)
+		MOD_DEC_USE_COUNT;
+	return err;
+}
+
+static void netem_destroy(struct Qdisc *sch)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+
+	del_timer(&q->timer);
+
+	qdisc_destroy(q->qdisc);
+	q->qdisc = &noop_qdisc;
+
+	MOD_DEC_USE_COUNT;
+}
+
+static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+	unsigned char	 *b = skb->tail;
+	struct tc_netem_qopt qopt;
+
+	qopt.latency = q->latency;
+	qopt.jitter = q->jitter;
+	qopt.limit = q->limit;
+	qopt.loss = q->loss;
+	qopt.gap = q->gap;
+
+	RTA_PUT(skb, TCA_OPTIONS, sizeof(qopt), &qopt);
+
+	return skb->len;
+
+rtattr_failure:
+	skb_trim(skb, b - skb->data);
+	return -1;
+}
+
+static int netem_dump_class(struct Qdisc *sch, unsigned long cl,
+			  struct sk_buff *skb, struct tcmsg *tcm)
+{
+	struct netem_sched_data *q = (struct netem_sched_data*)sch->data;
+
+	if (cl != 1) 	/* only one class */
+		return -ENOENT;
+
+	tcm->tcm_handle |= TC_H_MIN(1);
+	tcm->tcm_info = q->qdisc->handle;
+
+	return 0;
+}
+
+static int netem_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
+		     struct Qdisc **old)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+
+	if (new == NULL)
+		new = &noop_qdisc;
+
+	sch_tree_lock(sch);
+	*old = xchg(&q->qdisc, new);
+	qdisc_reset(*old);
+	sch->q.qlen = 0;
+	sch_tree_unlock(sch);
+
+	return 0;
+}
+
+static struct Qdisc *netem_leaf(struct Qdisc *sch, unsigned long arg)
+{
+	struct netem_sched_data *q = (struct netem_sched_data *)sch->data;
+	return q->qdisc;
+}
+
+static unsigned long netem_get(struct Qdisc *sch, u32 classid)
+{
+	return 1;
+}
+
+static void netem_put(struct Qdisc *sch, unsigned long arg)
+{
+}
+
+static int netem_change_class(struct Qdisc *sch, u32 classid, u32 parentid, 
+			    struct rtattr **tca, unsigned long *arg)
+{
+	return -ENOSYS;
+}
+
+static int netem_delete(struct Qdisc *sch, unsigned long arg)
+{
+	return -ENOSYS;
+}
+
+static void netem_walk(struct Qdisc *sch, struct qdisc_walker *walker)
+{
+	if (!walker->stop) {
+		if (walker->count >= walker->skip)
+			if (walker->fn(sch, 1, walker) < 0) {
+				walker->stop = 1;
+				return;
+			}
+		walker->count++;
+	}
+}
+
+static struct tcf_proto **netem_find_tcf(struct Qdisc *sch, unsigned long cl)
+{
+	return NULL;
+}
+
+static struct Qdisc_class_ops netem_class_ops = {
+	.graft		=	netem_graft,
+	.leaf		=	netem_leaf,
+	.get		=	netem_get,
+	.put		=	netem_put,
+	.change		=	netem_change_class,
+	.delete		=	netem_delete,
+	.walk		=	netem_walk,
+	.tcf_chain	=	netem_find_tcf,
+	.dump		=	netem_dump_class,
+};
+
+static struct Qdisc_ops netem_qdisc_ops = {
+	.id		=	"netem",
+	.cl_ops		=	&netem_class_ops,
+	.priv_size	=	sizeof(struct netem_sched_data),
+	.enqueue	=	netem_enqueue,
+	.dequeue	=	netem_dequeue,
+	.requeue	=	netem_requeue,
+	.drop		=	netem_drop,
+	.init		=	netem_init,
+	.reset		=	netem_reset,
+	.destroy	=	netem_destroy,
+	.change		=	netem_change,
+	.dump		=	netem_dump,
+};
+
+
+static int __init netem_module_init(void)
+{
+	return register_qdisc(&netem_qdisc_ops);
+}
+static void __exit netem_module_exit(void)
+{
+	unregister_qdisc(&netem_qdisc_ops);
+}
+module_init(netem_module_init)
+module_exit(netem_module_exit)
+MODULE_LICENSE("GPL");
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)