From 12d6066c3b29c5606c4a2466f964fbd9ede803c5 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Tue, 24 Jul 2018 16:37:40 +0300 Subject: [PATCH 1/1] net/mlx5: Add flow counters idr Previous patch in series changed flow counter storage structure from rb_tree to linked list in order to improve flow counter traversal performance. The drawback of such solution is that flow counter lookup by id becomes linear in complexity. Store pointers to flow counters in idr in order to improve lookup performance to logarithmic again. Idr is non-intrusive data structure and doesn't require extending flow counter struct with new elements. This means that idr can be used for lookup, while linked list from previous patch is used for traversal, and struct mlx5_fc size is <= 2 cache lines. Signed-off-by: Vlad Buslov Acked-by: Amir Vadai Reviewed-by: Paul Blakey Signed-off-by: Saeed Mahameed --- .../ethernet/mellanox/mlx5/core/fs_counters.c | 37 +++++++++++++++++-- include/linux/mlx5/driver.h | 2 + 2 files changed, 35 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c b/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c index 90ebfee37508..09206c4acd9a 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c @@ -77,13 +77,18 @@ static struct list_head *mlx5_fc_counters_lookup_next(struct mlx5_core_dev *dev, u32 id) { struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats; + unsigned long next_id = (unsigned long)id + 1; struct mlx5_fc *counter; - list_for_each_entry(counter, &fc_stats->counters, list) - if (counter->id > id) - return &counter->list; + rcu_read_lock(); + /* skip counters that are in idr, but not yet in counters list */ + while ((counter = idr_get_next_ul(&fc_stats->counters_idr, + &next_id)) != NULL && + list_empty(&counter->list)) + next_id++; + rcu_read_unlock(); - return &fc_stats->counters; + return counter ? &counter->list : &fc_stats->counters; } static void mlx5_fc_stats_insert(struct mlx5_core_dev *dev, @@ -214,15 +219,29 @@ struct mlx5_fc *mlx5_fc_create(struct mlx5_core_dev *dev, bool aging) counter = kzalloc(sizeof(*counter), GFP_KERNEL); if (!counter) return ERR_PTR(-ENOMEM); + INIT_LIST_HEAD(&counter->list); err = mlx5_cmd_fc_alloc(dev, &counter->id); if (err) goto err_out; if (aging) { + u32 id = counter->id; + counter->cache.lastuse = jiffies; counter->aging = true; + idr_preload(GFP_KERNEL); + spin_lock(&fc_stats->counters_idr_lock); + + err = idr_alloc_u32(&fc_stats->counters_idr, counter, &id, id, + GFP_NOWAIT); + + spin_unlock(&fc_stats->counters_idr_lock); + idr_preload_end(); + if (err) + goto err_out_alloc; + llist_add(&counter->addlist, &fc_stats->addlist); mod_delayed_work(fc_stats->wq, &fc_stats->work, 0); @@ -230,6 +249,8 @@ struct mlx5_fc *mlx5_fc_create(struct mlx5_core_dev *dev, bool aging) return counter; +err_out_alloc: + mlx5_cmd_fc_free(dev, counter->id); err_out: kfree(counter); @@ -245,6 +266,10 @@ void mlx5_fc_destroy(struct mlx5_core_dev *dev, struct mlx5_fc *counter) return; if (counter->aging) { + spin_lock(&fc_stats->counters_idr_lock); + WARN_ON(!idr_remove(&fc_stats->counters_idr, counter->id)); + spin_unlock(&fc_stats->counters_idr_lock); + llist_add(&counter->dellist, &fc_stats->dellist); mod_delayed_work(fc_stats->wq, &fc_stats->work, 0); return; @@ -258,6 +283,8 @@ int mlx5_init_fc_stats(struct mlx5_core_dev *dev) { struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats; + spin_lock_init(&fc_stats->counters_idr_lock); + idr_init(&fc_stats->counters_idr); INIT_LIST_HEAD(&fc_stats->counters); init_llist_head(&fc_stats->addlist); init_llist_head(&fc_stats->dellist); @@ -283,6 +310,8 @@ void mlx5_cleanup_fc_stats(struct mlx5_core_dev *dev) destroy_workqueue(dev->priv.fc_stats.wq); dev->priv.fc_stats.wq = NULL; + idr_destroy(&fc_stats->counters_idr); + tmplist = llist_del_all(&fc_stats->addlist); llist_for_each_entry_safe(counter, tmp, tmplist, addlist) mlx5_free_fc(dev, counter); diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h index 61bed33e6675..2a0c845f6bdb 100644 --- a/include/linux/mlx5/driver.h +++ b/include/linux/mlx5/driver.h @@ -583,6 +583,8 @@ struct mlx5_irq_info { }; struct mlx5_fc_stats { + spinlock_t counters_idr_lock; /* protects counters_idr */ + struct idr counters_idr; struct list_head counters; struct llist_head addlist; struct llist_head dellist; -- 2.34.1