net/mlx5: Store flow counters in a list
authorVlad Buslov <vladbu@mellanox.com>
Tue, 24 Jul 2018 06:52:11 +0000 (09:52 +0300)
committerSaeed Mahameed <saeedm@mellanox.com>
Thu, 6 Sep 2018 04:14:57 +0000 (21:14 -0700)
commit9aff93d7d0d4b3f3076d7bd12a4ad06ef1cf9804
tree0941d5daab6315479f9f3446b001ccd2629c65f4
parent6e5e22839136fdb466af0aa46ff2404713dff974
net/mlx5: Store flow counters in a list

In order to improve performance of flow counter stats query loop that
traverses all configured flow counters, replace rb_tree with double-linked
list. This change improves performance of traversing flow counters by
removing the tree traversal. (profiling data showed that call to rb_next
was most top CPU consumer)

However, lookup of flow flow counter in list becomes linear, instead of
logarithmic. This problem is fixed by next patch in series, which adds idr
for fast lookup. Idr is to be used because it is not an intrusive data
structure and doesn't require adding any new members to struct mlx5_fc,
which allows its control data part to stay <= 1 cache line in size.

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Amir Vadai <amir@vadai.me>
Reviewed-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c
include/linux/mlx5/driver.h