diff options
Diffstat (limited to 'include/net/sch_generic.h')
-rw-r--r-- | include/net/sch_generic.h | 129 |
1 files changed, 68 insertions, 61 deletions
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index 1e625519ae96..22179b2fda72 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -37,8 +37,22 @@ enum qdisc_state_t { __QDISC_STATE_SCHED, __QDISC_STATE_DEACTIVATED, __QDISC_STATE_MISSED, + __QDISC_STATE_DRAINING, }; +enum qdisc_state2_t { + /* Only for !TCQ_F_NOLOCK qdisc. Never access it directly. + * Use qdisc_run_begin/end() or qdisc_is_running() instead. + */ + __QDISC_STATE2_RUNNING, +}; + +#define QDISC_STATE_MISSED BIT(__QDISC_STATE_MISSED) +#define QDISC_STATE_DRAINING BIT(__QDISC_STATE_DRAINING) + +#define QDISC_STATE_NON_EMPTY (QDISC_STATE_MISSED | \ + QDISC_STATE_DRAINING) + struct qdisc_size_table { struct rcu_head rcu; struct list_head list; @@ -90,7 +104,7 @@ struct Qdisc { struct netdev_queue *dev_queue; struct net_rate_estimator __rcu *rate_est; - struct gnet_stats_basic_cpu __percpu *cpu_bstats; + struct gnet_stats_basic_sync __percpu *cpu_bstats; struct gnet_stats_queue __percpu *cpu_qstats; int pad; refcount_t refcnt; @@ -100,18 +114,16 @@ struct Qdisc { */ struct sk_buff_head gso_skb ____cacheline_aligned_in_smp; struct qdisc_skb_head q; - struct gnet_stats_basic_packed bstats; - seqcount_t running; + struct gnet_stats_basic_sync bstats; struct gnet_stats_queue qstats; unsigned long state; + unsigned long state2; /* must be written under qdisc spinlock */ struct Qdisc *next_sched; struct sk_buff_head skb_bad_txq; spinlock_t busylock ____cacheline_aligned_in_smp; spinlock_t seqlock; - /* for NOLOCK qdisc, true if there are no enqueued skbs */ - bool empty; struct rcu_head rcu; /* private data */ @@ -138,11 +150,20 @@ static inline struct Qdisc *qdisc_refcount_inc_nz(struct Qdisc *qdisc) return NULL; } +/* For !TCQ_F_NOLOCK qdisc: callers must either call this within a qdisc + * root_lock section, or provide their own memory barriers -- ordering + * against qdisc_run_begin/end() atomic bit operations. + */ static inline bool qdisc_is_running(struct Qdisc *qdisc) { if (qdisc->flags & TCQ_F_NOLOCK) return spin_is_locked(&qdisc->seqlock); - return (raw_read_seqcount(&qdisc->running) & 1) ? true : false; + return test_bit(__QDISC_STATE2_RUNNING, &qdisc->state2); +} + +static inline bool nolock_qdisc_is_empty(const struct Qdisc *qdisc) +{ + return !(READ_ONCE(qdisc->state) & QDISC_STATE_NON_EMPTY); } static inline bool qdisc_is_percpu_stats(const struct Qdisc *q) @@ -153,15 +174,24 @@ static inline bool qdisc_is_percpu_stats(const struct Qdisc *q) static inline bool qdisc_is_empty(const struct Qdisc *qdisc) { if (qdisc_is_percpu_stats(qdisc)) - return READ_ONCE(qdisc->empty); + return nolock_qdisc_is_empty(qdisc); return !READ_ONCE(qdisc->q.qlen); } +/* For !TCQ_F_NOLOCK qdisc, qdisc_run_begin/end() must be invoked with + * the qdisc root lock acquired. + */ static inline bool qdisc_run_begin(struct Qdisc *qdisc) { if (qdisc->flags & TCQ_F_NOLOCK) { if (spin_trylock(&qdisc->seqlock)) - goto nolock_empty; + return true; + + /* Paired with smp_mb__after_atomic() to make sure + * STATE_MISSED checking is synchronized with clearing + * in pfifo_fast_dequeue(). + */ + smp_mb__before_atomic(); /* If the MISSED flag is set, it means other thread has * set the MISSED flag before second spin_trylock(), so @@ -180,36 +210,30 @@ static inline bool qdisc_run_begin(struct Qdisc *qdisc) */ set_bit(__QDISC_STATE_MISSED, &qdisc->state); + /* spin_trylock() only has load-acquire semantic, so use + * smp_mb__after_atomic() to ensure STATE_MISSED is set + * before doing the second spin_trylock(). + */ + smp_mb__after_atomic(); + /* Retry again in case other CPU may not see the new flag * after it releases the lock at the end of qdisc_run_end(). */ - if (!spin_trylock(&qdisc->seqlock)) - return false; - -nolock_empty: - WRITE_ONCE(qdisc->empty, false); - } else if (qdisc_is_running(qdisc)) { - return false; + return spin_trylock(&qdisc->seqlock); } - /* 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; + return !__test_and_set_bit(__QDISC_STATE2_RUNNING, &qdisc->state2); } static inline void qdisc_run_end(struct Qdisc *qdisc) { - write_seqcount_end(&qdisc->running); if (qdisc->flags & TCQ_F_NOLOCK) { spin_unlock(&qdisc->seqlock); if (unlikely(test_bit(__QDISC_STATE_MISSED, - &qdisc->state))) { - clear_bit(__QDISC_STATE_MISSED, &qdisc->state); + &qdisc->state))) __netif_schedule(qdisc); - } + } else { + __clear_bit(__QDISC_STATE2_RUNNING, &qdisc->state2); } } @@ -291,6 +315,8 @@ struct Qdisc_ops { struct netlink_ext_ack *extack); void (*attach)(struct Qdisc *sch); int (*change_tx_queue_len)(struct Qdisc *, unsigned int); + void (*change_real_num_tx)(struct Qdisc *sch, + unsigned int new_real_tx); int (*dump)(struct Qdisc *, struct sk_buff *); int (*dump_stats)(struct Qdisc *, struct gnet_dump *); @@ -340,7 +366,7 @@ struct tcf_proto_ops { int (*change)(struct net *net, struct sk_buff *, struct tcf_proto*, unsigned long, u32 handle, struct nlattr **, - void **, bool, bool, + void **, u32, struct netlink_ext_ack *); int (*delete)(struct tcf_proto *tp, void *arg, bool *last, bool rtnl_held, @@ -573,14 +599,6 @@ static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc) 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; @@ -667,6 +685,8 @@ void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *); void qdisc_class_hash_destroy(struct Qdisc_class_hash *); int dev_qdisc_change_tx_queue_len(struct net_device *dev); +void dev_qdisc_change_real_num_tx(struct net_device *dev, + unsigned int new_real_tx); void dev_init_scheduler(struct net_device *dev); void dev_shutdown(struct net_device *dev); void dev_activate(struct net_device *dev); @@ -828,14 +848,16 @@ static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch, return sch->enqueue(skb, sch, to_free); } -static inline void _bstats_update(struct gnet_stats_basic_packed *bstats, +static inline void _bstats_update(struct gnet_stats_basic_sync *bstats, __u64 bytes, __u32 packets) { - bstats->bytes += bytes; - bstats->packets += packets; + u64_stats_update_begin(&bstats->syncp); + u64_stats_add(&bstats->bytes, bytes); + u64_stats_add(&bstats->packets, packets); + u64_stats_update_end(&bstats->syncp); } -static inline void bstats_update(struct gnet_stats_basic_packed *bstats, +static inline void bstats_update(struct gnet_stats_basic_sync *bstats, const struct sk_buff *skb) { _bstats_update(bstats, @@ -843,26 +865,10 @@ static inline void bstats_update(struct gnet_stats_basic_packed *bstats, 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); + bstats_update(this_cpu_ptr(sch->cpu_bstats), skb); } static inline void qdisc_bstats_update(struct Qdisc *sch, @@ -951,10 +957,9 @@ static inline void qdisc_qstats_qlen_backlog(struct Qdisc *sch, __u32 *qlen, __u32 *backlog) { struct gnet_stats_queue qstats = { 0 }; - __u32 len = qdisc_qlen_sum(sch); - __gnet_stats_copy_queue(&qstats, sch->cpu_qstats, &sch->qstats, len); - *qlen = qstats.qlen; + gnet_stats_add_queue(&qstats, sch->cpu_qstats, &sch->qstats); + *qlen = qstats.qlen + qdisc_qlen(sch); *backlog = qstats.backlog; } @@ -1295,15 +1300,15 @@ void psched_ppscfg_precompute(struct psched_pktrate *r, u64 pktrate64); struct mini_Qdisc { struct tcf_proto *filter_list; struct tcf_block *block; - struct gnet_stats_basic_cpu __percpu *cpu_bstats; + struct gnet_stats_basic_sync __percpu *cpu_bstats; struct gnet_stats_queue __percpu *cpu_qstats; - struct rcu_head rcu; + unsigned long rcu_state; }; static inline void mini_qdisc_bstats_cpu_update(struct mini_Qdisc *miniq, const struct sk_buff *skb) { - bstats_cpu_update(this_cpu_ptr(miniq->cpu_bstats), skb); + bstats_update(this_cpu_ptr(miniq->cpu_bstats), skb); } static inline void mini_qdisc_qstats_cpu_drop(struct mini_Qdisc *miniq) @@ -1324,6 +1329,8 @@ void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc, void mini_qdisc_pair_block_init(struct mini_Qdisc_pair *miniqp, struct tcf_block *block); +void mq_change_real_num_tx(struct Qdisc *sch, unsigned int new_real_tx); + int sch_frag_xmit_hook(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb)); #endif |