linux/include/net/pkt_sched.h
Patrick McHardy 641b9e0e8b [NET_SCHED]: Use ktime as clocksource
Get rid of the manual clock source selection mess and use ktime. Also
use a scalar representation, which allows to clean up pkt_sched.h a bit
more and results in less ktime_to_ns() calls in most cases.

The PSCHED_US2JIFFIE/PSCHED_JIFFIE2US macros are implemented quite
inefficient by this patch, following patches will convert all qdiscs
to hrtimers and get rid of them entirely.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:04 -07:00

100 lines
2.9 KiB
C

#ifndef __NET_PKT_SCHED_H
#define __NET_PKT_SCHED_H
#include <linux/jiffies.h>
#include <linux/ktime.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.
*/
typedef u64 psched_time_t;
typedef long psched_tdiff_t;
/* Avoid doing 64 bit divide by 1000 */
#define PSCHED_US2NS(x) ((s64)(x) << 10)
#define PSCHED_NS2US(x) ((x) >> 10)
#define PSCHED_TICKS_PER_SEC PSCHED_NS2US(NSEC_PER_SEC)
#define PSCHED_GET_TIME(stamp) \
((stamp) = PSCHED_NS2US(ktime_to_ns(ktime_get())))
#define PSCHED_US2JIFFIE(usecs) usecs_to_jiffies(PSCHED_US2NS((usecs)) / NSEC_PER_USEC)
#define PSCHED_JIFFIE2US(delay) PSCHED_NS2US(jiffies_to_usecs((delay)) * NSEC_PER_USEC)
#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)
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