1 #ifndef __NET_PKT_SCHED_H 2 #define __NET_PKT_SCHED_H 3 4 #include <linux/jiffies.h> 5 #include <net/sch_generic.h> 6 7 struct qdisc_walker 8 { 9 int stop; 10 int skip; 11 int count; 12 int (*fn)(struct Qdisc *, unsigned long cl, struct qdisc_walker *); 13 }; 14 15 extern rwlock_t qdisc_tree_lock; 16 17 #define QDISC_ALIGNTO 32 18 #define QDISC_ALIGN(len) (((len) + QDISC_ALIGNTO-1) & ~(QDISC_ALIGNTO-1)) 19 20 static inline void *qdisc_priv(struct Qdisc *q) 21 { 22 return (char *) q + QDISC_ALIGN(sizeof(struct Qdisc)); 23 } 24 25 /* 26 Timer resolution MUST BE < 10% of min_schedulable_packet_size/bandwidth 27 28 Normal IP packet size ~ 512byte, hence: 29 30 0.5Kbyte/1Mbyte/sec = 0.5msec, so that we need 50usec timer for 31 10Mbit ethernet. 32 33 10msec resolution -> <50Kbit/sec. 34 35 The result: [34]86 is not good choice for QoS router :-( 36 37 The things are not so bad, because we may use artifical 38 clock evaluated by integration of network data flow 39 in the most critical places. 40 41 Note: we do not use fastgettimeofday. 42 The reason is that, when it is not the same thing as 43 gettimeofday, it returns invalid timestamp, which is 44 not updated, when net_bh is active. 45 */ 46 47 /* General note about internal clock. 48 49 Any clock source returns time intervals, measured in units 50 close to 1usec. With source CONFIG_NET_SCH_CLK_GETTIMEOFDAY it is precisely 51 microseconds, otherwise something close but different chosen to minimize 52 arithmetic cost. Ratio usec/internal untis in form nominator/denominator 53 may be read from /proc/net/psched. 54 */ 55 56 57 #ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY 58 59 typedef struct timeval psched_time_t; 60 typedef long psched_tdiff_t; 61 62 #define PSCHED_GET_TIME(stamp) do_gettimeofday(&(stamp)) 63 #define PSCHED_US2JIFFIE(usecs) usecs_to_jiffies(usecs) 64 #define PSCHED_JIFFIE2US(delay) jiffies_to_usecs(delay) 65 66 #else /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */ 67 68 typedef u64 psched_time_t; 69 typedef long psched_tdiff_t; 70 71 #ifdef CONFIG_NET_SCH_CLK_JIFFIES 72 73 #if HZ < 96 74 #define PSCHED_JSCALE 14 75 #elif HZ >= 96 && HZ < 192 76 #define PSCHED_JSCALE 13 77 #elif HZ >= 192 && HZ < 384 78 #define PSCHED_JSCALE 12 79 #elif HZ >= 384 && HZ < 768 80 #define PSCHED_JSCALE 11 81 #elif HZ >= 768 82 #define PSCHED_JSCALE 10 83 #endif 84 85 #define PSCHED_GET_TIME(stamp) ((stamp) = (get_jiffies_64()<<PSCHED_JSCALE)) 86 #define PSCHED_US2JIFFIE(delay) (((delay)+(1<<PSCHED_JSCALE)-1)>>PSCHED_JSCALE) 87 #define PSCHED_JIFFIE2US(delay) ((delay)<<PSCHED_JSCALE) 88 89 #endif /* CONFIG_NET_SCH_CLK_JIFFIES */ 90 #ifdef CONFIG_NET_SCH_CLK_CPU 91 #include <asm/timex.h> 92 93 extern psched_tdiff_t psched_clock_per_hz; 94 extern int psched_clock_scale; 95 extern psched_time_t psched_time_base; 96 extern cycles_t psched_time_mark; 97 98 #define PSCHED_GET_TIME(stamp) \ 99 do { \ 100 cycles_t cur = get_cycles(); \ 101 if (sizeof(cycles_t) == sizeof(u32)) { \ 102 if (cur <= psched_time_mark) \ 103 psched_time_base += 0x100000000ULL; \ 104 psched_time_mark = cur; \ 105 (stamp) = (psched_time_base + cur)>>psched_clock_scale; \ 106 } else { \ 107 (stamp) = cur>>psched_clock_scale; \ 108 } \ 109 } while (0) 110 #define PSCHED_US2JIFFIE(delay) (((delay)+psched_clock_per_hz-1)/psched_clock_per_hz) 111 #define PSCHED_JIFFIE2US(delay) ((delay)*psched_clock_per_hz) 112 113 #endif /* CONFIG_NET_SCH_CLK_CPU */ 114 115 #endif /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */ 116 117 #ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY 118 #define PSCHED_TDIFF(tv1, tv2) \ 119 ({ \ 120 int __delta_sec = (tv1).tv_sec - (tv2).tv_sec; \ 121 int __delta = (tv1).tv_usec - (tv2).tv_usec; \ 122 if (__delta_sec) { \ 123 switch (__delta_sec) { \ 124 default: \ 125 __delta = 0; \ 126 case 2: \ 127 __delta += USEC_PER_SEC; \ 128 case 1: \ 129 __delta += USEC_PER_SEC; \ 130 } \ 131 } \ 132 __delta; \ 133 }) 134 135 static inline int 136 psched_tod_diff(int delta_sec, int bound) 137 { 138 int delta; 139 140 if (bound <= USEC_PER_SEC || delta_sec > (0x7FFFFFFF/USEC_PER_SEC)-1) 141 return bound; 142 delta = delta_sec * USEC_PER_SEC; 143 if (delta > bound || delta < 0) 144 delta = bound; 145 return delta; 146 } 147 148 #define PSCHED_TDIFF_SAFE(tv1, tv2, bound) \ 149 ({ \ 150 int __delta_sec = (tv1).tv_sec - (tv2).tv_sec; \ 151 int __delta = (tv1).tv_usec - (tv2).tv_usec; \ 152 switch (__delta_sec) { \ 153 default: \ 154 __delta = psched_tod_diff(__delta_sec, bound); break; \ 155 case 2: \ 156 __delta += USEC_PER_SEC; \ 157 case 1: \ 158 __delta += USEC_PER_SEC; \ 159 case 0: \ 160 if (__delta > bound || __delta < 0) \ 161 __delta = bound; \ 162 } \ 163 __delta; \ 164 }) 165 166 #define PSCHED_TLESS(tv1, tv2) (((tv1).tv_usec < (tv2).tv_usec && \ 167 (tv1).tv_sec <= (tv2).tv_sec) || \ 168 (tv1).tv_sec < (tv2).tv_sec) 169 170 #define PSCHED_TADD2(tv, delta, tv_res) \ 171 ({ \ 172 int __delta = (tv).tv_usec + (delta); \ 173 (tv_res).tv_sec = (tv).tv_sec; \ 174 if (__delta > USEC_PER_SEC) { (tv_res).tv_sec++; __delta -= USEC_PER_SEC; } \ 175 (tv_res).tv_usec = __delta; \ 176 }) 177 178 #define PSCHED_TADD(tv, delta) \ 179 ({ \ 180 (tv).tv_usec += (delta); \ 181 if ((tv).tv_usec > USEC_PER_SEC) { (tv).tv_sec++; \ 182 (tv).tv_usec -= USEC_PER_SEC; } \ 183 }) 184 185 /* Set/check that time is in the "past perfect"; 186 it depends on concrete representation of system time 187 */ 188 189 #define PSCHED_SET_PASTPERFECT(t) ((t).tv_sec = 0) 190 #define PSCHED_IS_PASTPERFECT(t) ((t).tv_sec == 0) 191 192 #define PSCHED_AUDIT_TDIFF(t) ({ if ((t) > 2000000) (t) = 2000000; }) 193 194 #else /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */ 195 196 #define PSCHED_TDIFF(tv1, tv2) (long)((tv1) - (tv2)) 197 #define PSCHED_TDIFF_SAFE(tv1, tv2, bound) \ 198 min_t(long long, (tv1) - (tv2), bound) 199 200 201 #define PSCHED_TLESS(tv1, tv2) ((tv1) < (tv2)) 202 #define PSCHED_TADD2(tv, delta, tv_res) ((tv_res) = (tv) + (delta)) 203 #define PSCHED_TADD(tv, delta) ((tv) += (delta)) 204 #define PSCHED_SET_PASTPERFECT(t) ((t) = 0) 205 #define PSCHED_IS_PASTPERFECT(t) ((t) == 0) 206 #define PSCHED_AUDIT_TDIFF(t) 207 208 #endif /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */ 209 210 extern struct Qdisc_ops pfifo_qdisc_ops; 211 extern struct Qdisc_ops bfifo_qdisc_ops; 212 213 extern int register_qdisc(struct Qdisc_ops *qops); 214 extern int unregister_qdisc(struct Qdisc_ops *qops); 215 extern struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle); 216 extern struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle); 217 extern struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, 218 struct rtattr *tab); 219 extern void qdisc_put_rtab(struct qdisc_rate_table *tab); 220 221 extern int qdisc_restart(struct net_device *dev); 222 223 static inline void qdisc_run(struct net_device *dev) 224 { 225 while (!netif_queue_stopped(dev) && qdisc_restart(dev) < 0) 226 /* NOTHING */; 227 } 228 229 extern int tc_classify(struct sk_buff *skb, struct tcf_proto *tp, 230 struct tcf_result *res); 231 232 /* Calculate maximal size of packet seen by hard_start_xmit 233 routine of this device. 234 */ 235 static inline unsigned psched_mtu(struct net_device *dev) 236 { 237 unsigned mtu = dev->mtu; 238 return dev->hard_header ? mtu + dev->hard_header_len : mtu; 239 } 240 241 #endif 242