tcfa_qstats is currently only used to hold drops and overlimits counters. tcf_action_inc_drop_qstats() and tcf_action_inc_overlimit_qstats() currently acquire a->tcfa_lock to increment these counters. Switch to two atomic_t to get lock-free accounting. Signed-off-by: Eric Dumazet --- include/net/act_api.h | 14 ++++++-------- net/sched/act_api.c | 12 ++++++++---- 2 files changed, 14 insertions(+), 12 deletions(-) diff --git a/include/net/act_api.h b/include/net/act_api.h index 2894cfff2da3..91a24b5e0b93 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -33,7 +33,10 @@ struct tc_action { struct tcf_t tcfa_tm; struct gnet_stats_basic_sync tcfa_bstats; struct gnet_stats_basic_sync tcfa_bstats_hw; - struct gnet_stats_queue tcfa_qstats; + + atomic_t tcfa_drops; + atomic_t tcfa_overlimits; + struct net_rate_estimator __rcu *tcfa_rate_est; spinlock_t tcfa_lock; struct gnet_stats_basic_sync __percpu *cpu_bstats; @@ -53,7 +56,6 @@ struct tc_action { #define tcf_action common.tcfa_action #define tcf_tm common.tcfa_tm #define tcf_bstats common.tcfa_bstats -#define tcf_qstats common.tcfa_qstats #define tcf_rate_est common.tcfa_rate_est #define tcf_lock common.tcfa_lock @@ -241,9 +243,7 @@ static inline void tcf_action_inc_drop_qstats(struct tc_action *a) qstats_drop_inc(this_cpu_ptr(a->cpu_qstats)); return; } - spin_lock(&a->tcfa_lock); - qstats_drop_inc(&a->tcfa_qstats); - spin_unlock(&a->tcfa_lock); + atomic_inc(&a->tcfa_drops); } static inline void tcf_action_inc_overlimit_qstats(struct tc_action *a) @@ -252,9 +252,7 @@ static inline void tcf_action_inc_overlimit_qstats(struct tc_action *a) qstats_overlimit_inc(this_cpu_ptr(a->cpu_qstats)); return; } - spin_lock(&a->tcfa_lock); - qstats_overlimit_inc(&a->tcfa_qstats); - spin_unlock(&a->tcfa_lock); + atomic_inc(&a->tcfa_overlimits); } void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets, diff --git a/net/sched/act_api.c b/net/sched/act_api.c index 9e468e463467..ff6be5cfe2b0 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -1585,7 +1585,7 @@ void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets, } _bstats_update(&a->tcfa_bstats, bytes, packets); - a->tcfa_qstats.drops += drops; + atomic_add(drops, &a->tcfa_drops); if (hw) _bstats_update(&a->tcfa_bstats_hw, bytes, packets); } @@ -1594,8 +1594,9 @@ EXPORT_SYMBOL(tcf_action_update_stats); int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p, int compat_mode) { - int err = 0; + struct gnet_stats_queue qstats = {0}; struct gnet_dump d; + int err = 0; if (p == NULL) goto errout; @@ -1619,14 +1620,17 @@ int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p, if (err < 0) goto errout; + qstats.drops = atomic_read(&p->tcfa_drops); + qstats.overlimits = atomic_read(&p->tcfa_overlimits); + if (gnet_stats_copy_basic(&d, p->cpu_bstats, &p->tcfa_bstats, false) < 0 || gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw, &p->tcfa_bstats_hw, false) < 0 || gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 || gnet_stats_copy_queue(&d, p->cpu_qstats, - &p->tcfa_qstats, - p->tcfa_qstats.qlen) < 0) + &qstats, + qstats.qlen) < 0) goto errout; if (gnet_stats_finish_copy(&d) < 0) -- 2.51.0.318.gd7df087d1a-goog