linux/include/net/sch_generic.h
Jesper Dangaard Brouer 5772e9a346 qdisc: bulk dequeue support for qdiscs with TCQ_F_ONETXQUEUE
Based on DaveM's recent API work on dev_hard_start_xmit(), that allows
sending/processing an entire skb list.

This patch implements qdisc bulk dequeue, by allowing multiple packets
to be dequeued in dequeue_skb().

The optimization principle for this is two fold, (1) to amortize
locking cost and (2) avoid expensive tailptr update for notifying HW.
 (1) Several packets are dequeued while holding the qdisc root_lock,
amortizing locking cost over several packet.  The dequeued SKB list is
processed under the TXQ lock in dev_hard_start_xmit(), thus also
amortizing the cost of the TXQ lock.
 (2) Further more, dev_hard_start_xmit() will utilize the skb->xmit_more
API to delay HW tailptr update, which also reduces the cost per
packet.

One restriction of the new API is that every SKB must belong to the
same TXQ.  This patch takes the easy way out, by restricting bulk
dequeue to qdisc's with the TCQ_F_ONETXQUEUE flag, that specifies the
qdisc only have attached a single TXQ.

Some detail about the flow; dev_hard_start_xmit() will process the skb
list, and transmit packets individually towards the driver (see
xmit_one()).  In case the driver stops midway in the list, the
remaining skb list is returned by dev_hard_start_xmit().  In
sch_direct_xmit() this returned list is requeued by dev_requeue_skb().

To avoid overshooting the HW limits, which results in requeuing, the
patch limits the amount of bytes dequeued, based on the drivers BQL
limits.  In-effect bulking will only happen for BQL enabled drivers.

Small amounts for extra HoL blocking (2x MTU/0.24ms) were
measured at 100Mbit/s, with bulking 8 packets, but the
oscillating nature of the measurement indicate something, like
sched latency might be causing this effect. More comparisons
show, that this oscillation goes away occationally. Thus, we
disregard this artifact completely and remove any "magic" bulking
limit.

For now, as a conservative approach, stop bulking when seeing TSO and
segmented GSO packets.  They already benefit from bulking on their own.
A followup patch add this, to allow easier bisect-ability for finding
regressions.

Jointed work with Hannes, Daniel and Florian.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-03 12:37:06 -07:00

808 lines
20 KiB
C

#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,
__QDISC_STATE_THROTTLED,
};
/*
* following bits are only changed while qdisc lock is held
*/
enum qdisc___state_t {
__QDISC___STATE_RUNNING = 1,
};
struct qdisc_size_table {
struct rcu_head rcu;
struct list_head list;
struct tc_sizespec szopts;
int refcnt;
u16 data[];
};
struct Qdisc {
int (*enqueue)(struct sk_buff *skb, struct Qdisc *dev);
struct sk_buff * (*dequeue)(struct Qdisc *dev);
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 */
u32 limit;
const struct Qdisc_ops *ops;
struct qdisc_size_table __rcu *stab;
struct list_head list;
u32 handle;
u32 parent;
int (*reshape_fail)(struct sk_buff *skb,
struct Qdisc *q);
void *u32_node;
/* This field is deprecated, but it is still used by CBQ
* and it will live until better solution will be invented.
*/
struct Qdisc *__parent;
struct netdev_queue *dev_queue;
struct gnet_stats_rate_est64 rate_est;
struct Qdisc *next_sched;
struct sk_buff *gso_skb;
/*
* For performance sake on SMP, we put highly modified fields at the end
*/
unsigned long state;
struct sk_buff_head q;
union {
struct gnet_stats_basic_packed bstats;
struct gnet_stats_basic_cpu __percpu *cpu_bstats;
} __packed;
unsigned int __state;
union {
struct gnet_stats_queue qstats;
struct gnet_stats_queue __percpu *cpu_qstats;
} __packed;
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 (qdisc->__state & __QDISC___STATE_RUNNING) ? true : false;
}
static inline bool qdisc_run_begin(struct Qdisc *qdisc)
{
if (qdisc_is_running(qdisc))
return false;
qdisc->__state |= __QDISC___STATE_RUNNING;
return true;
}
static inline void qdisc_run_end(struct Qdisc *qdisc)
{
qdisc->__state &= ~__QDISC___STATE_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
}
static inline bool qdisc_is_throttled(const struct Qdisc *qdisc)
{
return test_bit(__QDISC_STATE_THROTTLED, &qdisc->state) ? true : false;
}
static inline void qdisc_throttled(struct Qdisc *qdisc)
{
set_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
}
static inline void qdisc_unthrottled(struct Qdisc *qdisc)
{
clear_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
}
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);
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 *, struct Qdisc *);
struct sk_buff * (*dequeue)(struct Qdisc *);
struct sk_buff * (*peek)(struct Qdisc *);
unsigned int (*drop)(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*);
void (*destroy)(struct tcf_proto*);
unsigned long (*get)(struct tcf_proto*, u32 handle);
void (*put)(struct tcf_proto*, unsigned long);
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 _pad;
#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 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 const struct Qdisc_ops *default_qdisc_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_decrease_qlen(struct Qdisc *qdisc, unsigned int n);
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);
void tcf_destroy(struct tcf_proto *tp);
void tcf_destroy_chain(struct tcf_proto __rcu **fl);
/* 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)
{
qdisc_calculate_pkt_len(skb, sch);
return sch->enqueue(skb, sch);
}
static inline int qdisc_enqueue_root(struct sk_buff *skb, struct Qdisc *sch)
{
qdisc_skb_cb(skb)->pkt_len = skb->len;
return qdisc_enqueue(skb, sch) & NET_XMIT_MASK;
}
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,
const struct sk_buff *skb)
{
bstats->bytes += qdisc_pkt_len(skb);
bstats->packets += skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1;
}
static inline void qdisc_bstats_update_cpu(struct Qdisc *sch,
const struct sk_buff *skb)
{
struct gnet_stats_basic_cpu *bstats =
this_cpu_ptr(sch->cpu_bstats);
u64_stats_update_begin(&bstats->syncp);
bstats_update(&bstats->bstats, skb);
u64_stats_update_end(&bstats->syncp);
}
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 qdisc_qstats_drop(struct Qdisc *sch)
{
sch->qstats.drops++;
}
static inline void qdisc_qstats_drop_cpu(struct Qdisc *sch)
{
struct gnet_stats_queue *qstats = this_cpu_ptr(sch->cpu_qstats);
qstats->drops++;
}
static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
{
sch->qstats.overlimits++;
}
static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
struct sk_buff_head *list)
{
__skb_queue_tail(list, skb);
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 *sch,
struct sk_buff_head *list)
{
struct sk_buff *skb = __skb_dequeue(list);
if (likely(skb != NULL)) {
qdisc_qstats_backlog_dec(sch, skb);
qdisc_bstats_update(sch, skb);
}
return skb;
}
static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
{
return __qdisc_dequeue_head(sch, &sch->q);
}
static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
struct sk_buff_head *list)
{
struct sk_buff *skb = __skb_dequeue(list);
if (likely(skb != NULL)) {
unsigned int len = qdisc_pkt_len(skb);
qdisc_qstats_backlog_dec(sch, skb);
kfree_skb(skb);
return len;
}
return 0;
}
static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch)
{
return __qdisc_queue_drop_head(sch, &sch->q);
}
static inline struct sk_buff *__qdisc_dequeue_tail(struct Qdisc *sch,
struct sk_buff_head *list)
{
struct sk_buff *skb = __skb_dequeue_tail(list);
if (likely(skb != NULL))
qdisc_qstats_backlog_dec(sch, skb);
return skb;
}
static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch)
{
return __qdisc_dequeue_tail(sch, &sch->q);
}
static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
{
return skb_peek(&sch->q);
}
/* 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 */
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;
sch->q.qlen--;
} else {
skb = sch->dequeue(sch);
}
return skb;
}
static inline void __qdisc_reset_queue(struct Qdisc *sch,
struct sk_buff_head *list)
{
/*
* We do not know the backlog in bytes of this list, it
* is up to the caller to correct it
*/
__skb_queue_purge(list);
}
static inline void qdisc_reset_queue(struct Qdisc *sch)
{
__qdisc_reset_queue(sch, &sch->q);
sch->qstats.backlog = 0;
}
static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch,
struct sk_buff_head *list)
{
struct sk_buff *skb = __qdisc_dequeue_tail(sch, list);
if (likely(skb != NULL)) {
unsigned int len = qdisc_pkt_len(skb);
kfree_skb(skb);
return len;
}
return 0;
}
static inline unsigned int qdisc_queue_drop(struct Qdisc *sch)
{
return __qdisc_queue_drop(sch, &sch->q);
}
static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
{
kfree_skb(skb);
qdisc_qstats_drop(sch);
return NET_XMIT_DROP;
}
static inline int qdisc_reshape_fail(struct sk_buff *skb, struct Qdisc *sch)
{
qdisc_qstats_drop(sch);
#ifdef CONFIG_NET_CLS_ACT
if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch))
goto drop;
return NET_XMIT_SUCCESS;
drop:
#endif
kfree_skb(skb);
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];
}
#ifdef CONFIG_NET_CLS_ACT
static inline struct sk_buff *skb_act_clone(struct sk_buff *skb, gfp_t gfp_mask,
int action)
{
struct sk_buff *n;
n = skb_clone(skb, gfp_mask);
if (n) {
n->tc_verd = SET_TC_VERD(n->tc_verd, 0);
n->tc_verd = CLR_TC_OK2MUNGE(n->tc_verd);
n->tc_verd = CLR_TC_MUNGED(n->tc_verd);
}
return n;
}
#endif
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