RE: [PATCH bpf-next v5 1/2] docs/bpf: Add table to describe LRU properties

From: John Fastabend
Date: Sun Apr 23 2023 - 10:26:20 EST


Joe Stringer wrote:
> Depending on the map type and flags for LRU, different properties are
> global or percpu. Add a table to describe these.
>
> Signed-off-by: Joe Stringer <joe@xxxxxxxxxxxxx>
> ---
> v5: Use bold rather than verbatim for column header
> v4: Initial posting
> ---
> Documentation/bpf/map_hash.rst | 11 ++++++++++-
> 1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/bpf/map_hash.rst b/Documentation/bpf/map_hash.rst
> index 8669426264c6..1314dfc5e7e1 100644
> --- a/Documentation/bpf/map_hash.rst
> +++ b/Documentation/bpf/map_hash.rst
> @@ -29,7 +29,16 @@ will automatically evict the least recently used entries when the hash
> table reaches capacity. An LRU hash maintains an internal LRU list that
> is used to select elements for eviction. This internal LRU list is
> shared across CPUs but it is possible to request a per CPU LRU list with
> -the ``BPF_F_NO_COMMON_LRU`` flag when calling ``bpf_map_create``.
> +the ``BPF_F_NO_COMMON_LRU`` flag when calling ``bpf_map_create``. The
> +following table outlines the properties of LRU maps depending on the a
> +map type and the flags used to create the map.
> +
> +======================== ========================= ================================
> +Flag ``BPF_MAP_TYPE_LRU_HASH`` ``BPF_MAP_TYPE_LRU_PERCPU_HASH``
> +======================== ========================= ================================
> +**BPF_F_NO_COMMON_LRU** Per-CPU LRU, global map Per-CPU LRU, per-cpu map
> +**!BPF_F_NO_COMMON_LRU** Global LRU, global map Global LRU, per-cpu map
> +======================== ========================= ================================
>
> Usage
> =====
> --
> 2.34.1
>

Acked-by: John Fastabend <john.fastabend@xxxxxxxxx>