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#ifndef __NET_PKT_SCHED_H
#define __NET_PKT_SCHED_H
#include <linux/jiffies.h>
#include <net/sch_generic.h>
struct qdisc_walker
{
int stop;
int skip;
int count;
int (*fn)(struct Qdisc *, unsigned long cl, struct qdisc_walker *);
};
extern rwlock_t qdisc_tree_lock;
#define QDISC_ALIGNTO 32
#define QDISC_ALIGN(len) (((len) + QDISC_ALIGNTO-1) & ~(QDISC_ALIGNTO-1))
static inline void *qdisc_priv(struct Qdisc *q)
{
return (char *) q + QDISC_ALIGN(sizeof(struct Qdisc));
}
/*
Timer resolution MUST BE < 10% of min_schedulable_packet_size/bandwidth
Normal IP packet size ~ 512byte, hence:
0.5Kbyte/1Mbyte/sec = 0.5msec, so that we need 50usec timer for
10Mbit ethernet.
10msec resolution -> <50Kbit/sec.
The result: [34]86 is not good choice for QoS router :-(
The things are not so bad, because we may use artifical
clock evaluated by integration of network data flow
in the most critical places.
Note: we do not use fastgettimeofday.
The reason is that, when it is not the same thing as
gettimeofday, it returns invalid timestamp, which is
not updated, when net_bh is active.
*/
/* General note about internal clock.
Any clock source returns time intervals, measured in units
close to 1usec. With source CONFIG_NET_SCH_CLK_GETTIMEOFDAY it is precisely
microseconds, otherwise something close but different chosen to minimize
arithmetic cost. Ratio usec/internal untis in form nominator/denominator
may be read from /proc/net/psched.
*/
#ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY
typedef struct timeval psched_time_t;
typedef long psched_tdiff_t;
#define PSCHED_GET_TIME(stamp) do_gettimeofday(&(stamp))
#define PSCHED_US2JIFFIE(usecs) usecs_to_jiffies(usecs)
#define PSCHED_JIFFIE2US(delay) jiffies_to_usecs(delay)
#else /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */
typedef u64 psched_time_t;
typedef long psched_tdiff_t;
#ifdef CONFIG_NET_SCH_CLK_JIFFIES
#if HZ < 96
#define PSCHED_JSCALE 14
#elif HZ >= 96 && HZ < 192
#define PSCHED_JSCALE 13
#elif HZ >= 192 && HZ < 384
#define PSCHED_JSCALE 12
#elif HZ >= 384 && HZ < 768
#define PSCHED_JSCALE 11
#elif HZ >= 768
#define PSCHED_JSCALE 10
#endif
#define PSCHED_GET_TIME(stamp) ((stamp) = (get_jiffies_64()<<PSCHED_JSCALE))
#define PSCHED_US2JIFFIE(delay) (((delay)+(1<<PSCHED_JSCALE)-1)>>PSCHED_JSCALE)
#define PSCHED_JIFFIE2US(delay) ((delay)<<PSCHED_JSCALE)
#endif /* CONFIG_NET_SCH_CLK_JIFFIES */
#ifdef CONFIG_NET_SCH_CLK_CPU
#include <asm/timex.h>
extern psched_tdiff_t psched_clock_per_hz;
extern int psched_clock_scale;
extern psched_time_t psched_time_base;
extern cycles_t psched_time_mark;
#define PSCHED_GET_TIME(stamp) \
do { \
cycles_t cur = get_cycles(); \
if (sizeof(cycles_t) == sizeof(u32)) { \
if (cur <= psched_time_mark) \
psched_time_base += 0x100000000ULL; \
psched_time_mark = cur; \
(stamp) = (psched_time_base + cur)>>psched_clock_scale; \
} else { \
(stamp) = cur>>psched_clock_scale; \
} \
} while (0)
#define PSCHED_US2JIFFIE(delay) (((delay)+psched_clock_per_hz-1)/psched_clock_per_hz)
#define PSCHED_JIFFIE2US(delay) ((delay)*psched_clock_per_hz)
#endif /* CONFIG_NET_SCH_CLK_CPU */
#endif /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */
#ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY
#define PSCHED_TDIFF(tv1, tv2) \
({ \
int __delta_sec = (tv1).tv_sec - (tv2).tv_sec; \
int __delta = (tv1).tv_usec - (tv2).tv_usec; \
if (__delta_sec) { \
switch (__delta_sec) { \
default: \
__delta = 0; \
case 2: \
__delta += USEC_PER_SEC; \
case 1: \
__delta += USEC_PER_SEC; \
} \
} \
__delta; \
})
static inline int
psched_tod_diff(int delta_sec, int bound)
{
int delta;
if (bound <= USEC_PER_SEC || delta_sec > (0x7FFFFFFF/USEC_PER_SEC)-1)
return bound;
delta = delta_sec * USEC_PER_SEC;
if (delta > bound || delta < 0)
delta = bound;
return delta;
}
#define PSCHED_TDIFF_SAFE(tv1, tv2, bound) \
({ \
int __delta_sec = (tv1).tv_sec - (tv2).tv_sec; \
int __delta = (tv1).tv_usec - (tv2).tv_usec; \
switch (__delta_sec) { \
default: \
__delta = psched_tod_diff(__delta_sec, bound); break; \
case 2: \
__delta += USEC_PER_SEC; \
case 1: \
__delta += USEC_PER_SEC; \
case 0: \
if (__delta > bound || __delta < 0) \
__delta = bound; \
} \
__delta; \
})
#define PSCHED_TLESS(tv1, tv2) (((tv1).tv_usec < (tv2).tv_usec && \
(tv1).tv_sec <= (tv2).tv_sec) || \
(tv1).tv_sec < (tv2).tv_sec)
#define PSCHED_TADD2(tv, delta, tv_res) \
({ \
int __delta = (tv).tv_usec + (delta); \
(tv_res).tv_sec = (tv).tv_sec; \
while (__delta >= USEC_PER_SEC) { (tv_res).tv_sec++; __delta -= USEC_PER_SEC; } \
(tv_res).tv_usec = __delta; \
})
#define PSCHED_TADD(tv, delta) \
({ \
(tv).tv_usec += (delta); \
while ((tv).tv_usec >= USEC_PER_SEC) { (tv).tv_sec++; \
(tv).tv_usec -= USEC_PER_SEC; } \
})
/* Set/check that time is in the "past perfect";
it depends on concrete representation of system time
*/
#define PSCHED_SET_PASTPERFECT(t) ((t).tv_sec = 0)
#define PSCHED_IS_PASTPERFECT(t) ((t).tv_sec == 0)
#define PSCHED_AUDIT_TDIFF(t) ({ if ((t) > 2000000) (t) = 2000000; })
#else /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */
#define PSCHED_TDIFF(tv1, tv2) (long)((tv1) - (tv2))
#define PSCHED_TDIFF_SAFE(tv1, tv2, bound) \
min_t(long long, (tv1) - (tv2), bound)
#define PSCHED_TLESS(tv1, tv2) ((tv1) < (tv2))
#define PSCHED_TADD2(tv, delta, tv_res) ((tv_res) = (tv) + (delta))
#define PSCHED_TADD(tv, delta) ((tv) += (delta))
#define PSCHED_SET_PASTPERFECT(t) ((t) = 0)
#define PSCHED_IS_PASTPERFECT(t) ((t) == 0)
#define PSCHED_AUDIT_TDIFF(t)
#endif /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */
extern struct Qdisc_ops pfifo_qdisc_ops;
extern struct Qdisc_ops bfifo_qdisc_ops;
extern int register_qdisc(struct Qdisc_ops *qops);
extern int unregister_qdisc(struct Qdisc_ops *qops);
extern struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
extern struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle);
extern struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
struct rtattr *tab);
extern void qdisc_put_rtab(struct qdisc_rate_table *tab);
extern void __qdisc_run(struct net_device *dev);
static inline void qdisc_run(struct net_device *dev)
{
if (!netif_queue_stopped(dev) &&
!test_and_set_bit(__LINK_STATE_QDISC_RUNNING, &dev->state))
__qdisc_run(dev);
}
extern int tc_classify(struct sk_buff *skb, struct tcf_proto *tp,
struct tcf_result *res);
/* Calculate maximal size of packet seen by hard_start_xmit
routine of this device.
*/
static inline unsigned psched_mtu(struct net_device *dev)
{
unsigned mtu = dev->mtu;
return dev->hard_header ? mtu + dev->hard_header_len : mtu;
}
#endif
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