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linux/include/net/sch_generic.h
Eric Dumazet 1c0d32fde5 net_sched: gen_estimator: complete rewrite of rate estimators 
1) Old code was hard to maintain, due to complex lock chains.
   (We probably will be able to remove some kfree_rcu() in callers)

2) Using a single timer to update all estimators does not scale.

3) Code was buggy on 32bit kernel (WRITE_ONCE() on 64bit quantity
   is not supposed to work well)

In this rewrite :

- I removed the RB tree that had to be scanned in
  gen_estimator_active(). qdisc dumps should be much faster.

- Each estimator has its own timer.

- Estimations are maintained in net_rate_estimator structure,
  instead of dirtying the qdisc. Minor, but part of the simplification.

- Reading the estimator uses RCU and a seqcount to provide proper
  support for 32bit kernels.

- We reduce memory need when estimators are not used, since
  we store a pointer, instead of the bytes/packets counters.

- xt_rateest_mt() no longer has to grab a spinlock.
  (In the future, xt_rateest_tg() could be switched to per cpu counters)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-05 15:21:59 -05:00

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#ifndef __NET_SCHED_GENERIC_H
#define __NET_SCHED_GENERIC_H
#include <linux/netdevice.h>
#include <linux/types.h>
#include <linux/rcupdate.h>
#include <linux/pkt_sched.h>
#include <linux/pkt_cls.h>
#include <linux/percpu.h>
#include <linux/dynamic_queue_limits.h>
#include <net/gen_stats.h>
#include <net/rtnetlink.h>
struct Qdisc_ops;
struct qdisc_walker;
struct tcf_walker;
struct module;
struct qdisc_rate_table {
struct tc_ratespec rate;
u32 data[256];
struct qdisc_rate_table *next;
int refcnt;
};
enum qdisc_state_t {
__QDISC_STATE_SCHED,
__QDISC_STATE_DEACTIVATED,
};
struct qdisc_size_table {
struct rcu_head rcu;
struct list_head list;
struct tc_sizespec szopts;
int refcnt;
u16 data[];
};
/* similar to sk_buff_head, but skb->prev pointer is undefined. */
struct qdisc_skb_head {
struct sk_buff *head;
struct sk_buff *tail;
__u32 qlen;
spinlock_t lock;
};
struct Qdisc {
int (*enqueue)(struct sk_buff *skb,
struct Qdisc *sch,
struct sk_buff **to_free);
struct sk_buff * (*dequeue)(struct Qdisc *sch);
unsigned int flags;
#define TCQ_F_BUILTIN 1
#define TCQ_F_INGRESS 2
#define TCQ_F_CAN_BYPASS 4
#define TCQ_F_MQROOT 8
#define TCQ_F_ONETXQUEUE 0x10 /* dequeue_skb() can assume all skbs are for
* q->dev_queue : It can test
* netif_xmit_frozen_or_stopped() before
* dequeueing next packet.
* Its true for MQ/MQPRIO slaves, or non
* multiqueue device.
*/
#define TCQ_F_WARN_NONWC (1 << 16)
#define TCQ_F_CPUSTATS 0x20 /* run using percpu statistics */
#define TCQ_F_NOPARENT 0x40 /* root of its hierarchy :
* qdisc_tree_decrease_qlen() should stop.
*/
u32 limit;
const struct Qdisc_ops *ops;
struct qdisc_size_table __rcu *stab;
struct hlist_node hash;
u32 handle;
u32 parent;
void *u32_node;
struct netdev_queue *dev_queue;
struct net_rate_estimator __rcu *rate_est;
struct gnet_stats_basic_cpu __percpu *cpu_bstats;
struct gnet_stats_queue __percpu *cpu_qstats;
/*
* For performance sake on SMP, we put highly modified fields at the end
*/
struct sk_buff *gso_skb ____cacheline_aligned_in_smp;
struct qdisc_skb_head q;
struct gnet_stats_basic_packed bstats;
seqcount_t running;
struct gnet_stats_queue qstats;
unsigned long state;
struct Qdisc *next_sched;
struct sk_buff *skb_bad_txq;
struct rcu_head rcu_head;
int padded;
atomic_t refcnt;
spinlock_t busylock ____cacheline_aligned_in_smp;
};
static inline bool qdisc_is_running(const struct Qdisc *qdisc)
{
return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
}
static inline bool qdisc_run_begin(struct Qdisc *qdisc)
{
if (qdisc_is_running(qdisc))
return false;
/* Variant of write_seqcount_begin() telling lockdep a trylock
* was attempted.
*/
raw_write_seqcount_begin(&qdisc->running);
seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
return true;
}
static inline void qdisc_run_end(struct Qdisc *qdisc)
{
write_seqcount_end(&qdisc->running);
}
static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
{
return qdisc->flags & TCQ_F_ONETXQUEUE;
}
static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq)
{
#ifdef CONFIG_BQL
/* Non-BQL migrated drivers will return 0, too. */
return dql_avail(&txq->dql);
#else
return 0;
#endif
}
struct Qdisc_class_ops {
/* Child qdisc manipulation */
struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *);
int (*graft)(struct Qdisc *, unsigned long cl,
struct Qdisc *, struct Qdisc **);
struct Qdisc * (*leaf)(struct Qdisc *, unsigned long cl);
void (*qlen_notify)(struct Qdisc *, unsigned long);
/* Class manipulation routines */
unsigned long (*get)(struct Qdisc *, u32 classid);
void (*put)(struct Qdisc *, unsigned long);
int (*change)(struct Qdisc *, u32, u32,
struct nlattr **, unsigned long *);
int (*delete)(struct Qdisc *, unsigned long);
void (*walk)(struct Qdisc *, struct qdisc_walker * arg);
/* Filter manipulation */
struct tcf_proto __rcu ** (*tcf_chain)(struct Qdisc *, unsigned long);
bool (*tcf_cl_offload)(u32 classid);
unsigned long (*bind_tcf)(struct Qdisc *, unsigned long,
u32 classid);
void (*unbind_tcf)(struct Qdisc *, unsigned long);
/* rtnetlink specific */
int (*dump)(struct Qdisc *, unsigned long,
struct sk_buff *skb, struct tcmsg*);
int (*dump_stats)(struct Qdisc *, unsigned long,
struct gnet_dump *);
};
struct Qdisc_ops {
struct Qdisc_ops *next;
const struct Qdisc_class_ops *cl_ops;
char id[IFNAMSIZ];
int priv_size;
int (*enqueue)(struct sk_buff *skb,
struct Qdisc *sch,
struct sk_buff **to_free);
struct sk_buff * (*dequeue)(struct Qdisc *);
struct sk_buff * (*peek)(struct Qdisc *);
int (*init)(struct Qdisc *, struct nlattr *arg);
void (*reset)(struct Qdisc *);
void (*destroy)(struct Qdisc *);
int (*change)(struct Qdisc *, struct nlattr *arg);
void (*attach)(struct Qdisc *);
int (*dump)(struct Qdisc *, struct sk_buff *);
int (*dump_stats)(struct Qdisc *, struct gnet_dump *);
struct module *owner;
};
struct tcf_result {
unsigned long class;
u32 classid;
};
struct tcf_proto_ops {
struct list_head head;
char kind[IFNAMSIZ];
int (*classify)(struct sk_buff *,
const struct tcf_proto *,
struct tcf_result *);
int (*init)(struct tcf_proto*);
bool (*destroy)(struct tcf_proto*, bool);
unsigned long (*get)(struct tcf_proto*, u32 handle);
int (*change)(struct net *net, struct sk_buff *,
struct tcf_proto*, unsigned long,
u32 handle, struct nlattr **,
unsigned long *, bool);
int (*delete)(struct tcf_proto*, unsigned long);
void (*walk)(struct tcf_proto*, struct tcf_walker *arg);
/* rtnetlink specific */
int (*dump)(struct net*, struct tcf_proto*, unsigned long,
struct sk_buff *skb, struct tcmsg*);
struct module *owner;
};
struct tcf_proto {
/* Fast access part */
struct tcf_proto __rcu *next;
void __rcu *root;
int (*classify)(struct sk_buff *,
const struct tcf_proto *,
struct tcf_result *);
__be16 protocol;
/* All the rest */
u32 prio;
u32 classid;
struct Qdisc *q;
void *data;
const struct tcf_proto_ops *ops;
struct rcu_head rcu;
};
struct qdisc_skb_cb {
unsigned int pkt_len;
u16 slave_dev_queue_mapping;
u16 tc_classid;
#define QDISC_CB_PRIV_LEN 20
unsigned char data[QDISC_CB_PRIV_LEN];
};
static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
{
struct qdisc_skb_cb *qcb;
BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz);
BUILD_BUG_ON(sizeof(qcb->data) < sz);
}
static inline int qdisc_qlen(const struct Qdisc *q)
{
return q->q.qlen;
}
static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
{
return (struct qdisc_skb_cb *)skb->cb;
}
static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
{
return &qdisc->q.lock;
}
static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
{
struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc);
return q;
}
static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
{
return qdisc->dev_queue->qdisc_sleeping;
}
/* The qdisc root lock is a mechanism by which to top level
* of a qdisc tree can be locked from any qdisc node in the
* forest. This allows changing the configuration of some
* aspect of the qdisc tree while blocking out asynchronous
* qdisc access in the packet processing paths.
*
* It is only legal to do this when the root will not change
* on us. Otherwise we'll potentially lock the wrong qdisc
* root. This is enforced by holding the RTNL semaphore, which
* all users of this lock accessor must do.
*/
static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
{
struct Qdisc *root = qdisc_root(qdisc);
ASSERT_RTNL();
return qdisc_lock(root);
}
static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
{
struct Qdisc *root = qdisc_root_sleeping(qdisc);
ASSERT_RTNL();
return qdisc_lock(root);
}
static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
{
struct Qdisc *root = qdisc_root_sleeping(qdisc);
ASSERT_RTNL();
return &root->running;
}
static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
{
return qdisc->dev_queue->dev;
}
static inline void sch_tree_lock(const struct Qdisc *q)
{
spin_lock_bh(qdisc_root_sleeping_lock(q));
}
static inline void sch_tree_unlock(const struct Qdisc *q)
{
spin_unlock_bh(qdisc_root_sleeping_lock(q));
}
#define tcf_tree_lock(tp) sch_tree_lock((tp)->q)
#define tcf_tree_unlock(tp) sch_tree_unlock((tp)->q)
extern struct Qdisc noop_qdisc;
extern struct Qdisc_ops noop_qdisc_ops;
extern struct Qdisc_ops pfifo_fast_ops;
extern struct Qdisc_ops mq_qdisc_ops;
extern struct Qdisc_ops noqueue_qdisc_ops;
extern const struct Qdisc_ops *default_qdisc_ops;
static inline const struct Qdisc_ops *
get_default_qdisc_ops(const struct net_device *dev, int ntx)
{
return ntx < dev->real_num_tx_queues ?
default_qdisc_ops : &pfifo_fast_ops;
}
struct Qdisc_class_common {
u32 classid;
struct hlist_node hnode;
};
struct Qdisc_class_hash {
struct hlist_head *hash;
unsigned int hashsize;
unsigned int hashmask;
unsigned int hashelems;
};
static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
{
id ^= id >> 8;
id ^= id >> 4;
return id & mask;
}
static inline struct Qdisc_class_common *
qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
{
struct Qdisc_class_common *cl;
unsigned int h;
h = qdisc_class_hash(id, hash->hashmask);
hlist_for_each_entry(cl, &hash->hash[h], hnode) {
if (cl->classid == id)
return cl;
}
return NULL;
}
int qdisc_class_hash_init(struct Qdisc_class_hash *);
void qdisc_class_hash_insert(struct Qdisc_class_hash *,
struct Qdisc_class_common *);
void qdisc_class_hash_remove(struct Qdisc_class_hash *,
struct Qdisc_class_common *);
void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
void dev_init_scheduler(struct net_device *dev);
void dev_shutdown(struct net_device *dev);
void dev_activate(struct net_device *dev);
void dev_deactivate(struct net_device *dev);
void dev_deactivate_many(struct list_head *head);
struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
struct Qdisc *qdisc);
void qdisc_reset(struct Qdisc *qdisc);
void qdisc_destroy(struct Qdisc *qdisc);
void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n,
unsigned int len);
struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
const struct Qdisc_ops *ops);
struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
const struct Qdisc_ops *ops, u32 parentid);
void __qdisc_calculate_pkt_len(struct sk_buff *skb,
const struct qdisc_size_table *stab);
bool tcf_destroy(struct tcf_proto *tp, bool force);
void tcf_destroy_chain(struct tcf_proto __rcu **fl);
int skb_do_redirect(struct sk_buff *);
static inline bool skb_at_tc_ingress(const struct sk_buff *skb)
{
#ifdef CONFIG_NET_CLS_ACT
return G_TC_AT(skb->tc_verd) & AT_INGRESS;
#else
return false;
#endif
}
/* Reset all TX qdiscs greater then index of a device. */
static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
{
struct Qdisc *qdisc;
for (; i < dev->num_tx_queues; i++) {
qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc);
if (qdisc) {
spin_lock_bh(qdisc_lock(qdisc));
qdisc_reset(qdisc);
spin_unlock_bh(qdisc_lock(qdisc));
}
}
}
static inline void qdisc_reset_all_tx(struct net_device *dev)
{
qdisc_reset_all_tx_gt(dev, 0);
}
/* Are all TX queues of the device empty? */
static inline bool qdisc_all_tx_empty(const struct net_device *dev)
{
unsigned int i;
rcu_read_lock();
for (i = 0; i < dev->num_tx_queues; i++) {
struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
const struct Qdisc *q = rcu_dereference(txq->qdisc);
if (q->q.qlen) {
rcu_read_unlock();
return false;
}
}
rcu_read_unlock();
return true;
}
/* Are any of the TX qdiscs changing? */
static inline bool qdisc_tx_changing(const struct net_device *dev)
{
unsigned int i;
for (i = 0; i < dev->num_tx_queues; i++) {
struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping)
return true;
}
return false;
}
/* Is the device using the noop qdisc on all queues? */
static inline bool qdisc_tx_is_noop(const struct net_device *dev)
{
unsigned int i;
for (i = 0; i < dev->num_tx_queues; i++) {
struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
if (rcu_access_pointer(txq->qdisc) != &noop_qdisc)
return false;
}
return true;
}
static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
{
return qdisc_skb_cb(skb)->pkt_len;
}
/* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
enum net_xmit_qdisc_t {
__NET_XMIT_STOLEN = 0x00010000,
__NET_XMIT_BYPASS = 0x00020000,
};
#ifdef CONFIG_NET_CLS_ACT
#define net_xmit_drop_count(e) ((e) & __NET_XMIT_STOLEN ? 0 : 1)
#else
#define net_xmit_drop_count(e) (1)
#endif
static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
const struct Qdisc *sch)
{
#ifdef CONFIG_NET_SCHED
struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
if (stab)
__qdisc_calculate_pkt_len(skb, stab);
#endif
}
static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
struct sk_buff **to_free)
{
qdisc_calculate_pkt_len(skb, sch);
return sch->enqueue(skb, sch, to_free);
}
static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
{
return q->flags & TCQ_F_CPUSTATS;
}
static inline void _bstats_update(struct gnet_stats_basic_packed *bstats,
__u64 bytes, __u32 packets)
{
bstats->bytes += bytes;
bstats->packets += packets;
}
static inline void bstats_update(struct gnet_stats_basic_packed *bstats,
const struct sk_buff *skb)
{
_bstats_update(bstats,
qdisc_pkt_len(skb),
skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1);
}
static inline void _bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
__u64 bytes, __u32 packets)
{
u64_stats_update_begin(&bstats->syncp);
_bstats_update(&bstats->bstats, bytes, packets);
u64_stats_update_end(&bstats->syncp);
}
static inline void bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
const struct sk_buff *skb)
{
u64_stats_update_begin(&bstats->syncp);
bstats_update(&bstats->bstats, skb);
u64_stats_update_end(&bstats->syncp);
}
static inline void qdisc_bstats_cpu_update(struct Qdisc *sch,
const struct sk_buff *skb)
{
bstats_cpu_update(this_cpu_ptr(sch->cpu_bstats), skb);
}
static inline void qdisc_bstats_update(struct Qdisc *sch,
const struct sk_buff *skb)
{
bstats_update(&sch->bstats, skb);
}
static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch,
const struct sk_buff *skb)
{
sch->qstats.backlog -= qdisc_pkt_len(skb);
}
static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch,
const struct sk_buff *skb)
{
sch->qstats.backlog += qdisc_pkt_len(skb);
}
static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count)
{
sch->qstats.drops += count;
}
static inline void qstats_drop_inc(struct gnet_stats_queue *qstats)
{
qstats->drops++;
}
static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats)
{
qstats->overlimits++;
}
static inline void qdisc_qstats_drop(struct Qdisc *sch)
{
qstats_drop_inc(&sch->qstats);
}
static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch)
{
this_cpu_inc(sch->cpu_qstats->drops);
}
static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
{
sch->qstats.overlimits++;
}
static inline void qdisc_skb_head_init(struct qdisc_skb_head *qh)
{
qh->head = NULL;
qh->tail = NULL;
qh->qlen = 0;
}
static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
struct qdisc_skb_head *qh)
{
struct sk_buff *last = qh->tail;
if (last) {
skb->next = NULL;
last->next = skb;
qh->tail = skb;
} else {
qh->tail = skb;
qh->head = skb;
}
qh->qlen++;
qdisc_qstats_backlog_inc(sch, skb);
return NET_XMIT_SUCCESS;
}
static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
{
return __qdisc_enqueue_tail(skb, sch, &sch->q);
}
static inline struct sk_buff *__qdisc_dequeue_head(struct qdisc_skb_head *qh)
{
struct sk_buff *skb = qh->head;
if (likely(skb != NULL)) {
qh->head = skb->next;
qh->qlen--;
if (qh->head == NULL)
qh->tail = NULL;
skb->next = NULL;
}
return skb;
}
static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
{
struct sk_buff *skb = __qdisc_dequeue_head(&sch->q);
if (likely(skb != NULL)) {
qdisc_qstats_backlog_dec(sch, skb);
qdisc_bstats_update(sch, skb);
}
return skb;
}
/* Instead of calling kfree_skb() while root qdisc lock is held,
* queue the skb for future freeing at end of __dev_xmit_skb()
*/
static inline void __qdisc_drop(struct sk_buff *skb, struct sk_buff **to_free)
{
skb->next = *to_free;
*to_free = skb;
}
static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
struct qdisc_skb_head *qh,
struct sk_buff **to_free)
{
struct sk_buff *skb = __qdisc_dequeue_head(qh);
if (likely(skb != NULL)) {
unsigned int len = qdisc_pkt_len(skb);
qdisc_qstats_backlog_dec(sch, skb);
__qdisc_drop(skb, to_free);
return len;
}
return 0;
}
static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch,
struct sk_buff **to_free)
{
return __qdisc_queue_drop_head(sch, &sch->q, to_free);
}
static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
{
const struct qdisc_skb_head *qh = &sch->q;
return qh->head;
}
/* generic pseudo peek method for non-work-conserving qdisc */
static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
{
/* we can reuse ->gso_skb because peek isn't called for root qdiscs */
if (!sch->gso_skb) {
sch->gso_skb = sch->dequeue(sch);
if (sch->gso_skb) {
/* it's still part of the queue */
qdisc_qstats_backlog_inc(sch, sch->gso_skb);
sch->q.qlen++;
}
}
return sch->gso_skb;
}
/* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
{
struct sk_buff *skb = sch->gso_skb;
if (skb) {
sch->gso_skb = NULL;
qdisc_qstats_backlog_dec(sch, skb);
sch->q.qlen--;
} else {
skb = sch->dequeue(sch);
}
return skb;
}
static inline void __qdisc_reset_queue(struct qdisc_skb_head *qh)
{
/*
* We do not know the backlog in bytes of this list, it
* is up to the caller to correct it
*/
ASSERT_RTNL();
if (qh->qlen) {
rtnl_kfree_skbs(qh->head, qh->tail);
qh->head = NULL;
qh->tail = NULL;
qh->qlen = 0;
}
}
static inline void qdisc_reset_queue(struct Qdisc *sch)
{
__qdisc_reset_queue(&sch->q);
sch->qstats.backlog = 0;
}
static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
struct Qdisc **pold)
{
struct Qdisc *old;
sch_tree_lock(sch);
old = *pold;
*pold = new;
if (old != NULL) {
qdisc_tree_reduce_backlog(old, old->q.qlen, old->qstats.backlog);
qdisc_reset(old);
}
sch_tree_unlock(sch);
return old;
}
static inline void rtnl_qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
{
rtnl_kfree_skbs(skb, skb);
qdisc_qstats_drop(sch);
}
static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch,
struct sk_buff **to_free)
{
__qdisc_drop(skb, to_free);
qdisc_qstats_drop(sch);
return NET_XMIT_DROP;
}
/* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
long it will take to send a packet given its size.
*/
static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
{
int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
if (slot < 0)
slot = 0;
slot >>= rtab->rate.cell_log;
if (slot > 255)
return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
return rtab->data[slot];
}
struct psched_ratecfg {
u64 rate_bytes_ps; /* bytes per second */
u32 mult;
u16 overhead;
u8 linklayer;
u8 shift;
};
static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
unsigned int len)
{
len += r->overhead;
if (unlikely(r->linklayer == TC_LINKLAYER_ATM))
return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift;
return ((u64)len * r->mult) >> r->shift;
}
void psched_ratecfg_precompute(struct psched_ratecfg *r,
const struct tc_ratespec *conf,
u64 rate64);
static inline void psched_ratecfg_getrate(struct tc_ratespec *res,
const struct psched_ratecfg *r)
{
memset(res, 0, sizeof(*res));
/* legacy struct tc_ratespec has a 32bit @rate field
* Qdisc using 64bit rate should add new attributes
* in order to maintain compatibility.
*/
res->rate = min_t(u64, r->rate_bytes_ps, ~0U);
res->overhead = r->overhead;
res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
}
#endif
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