tools: bpftool: add map create command

Add a way of creating maps from user space.  The command takes
as parameters most of the attributes of the map creation system
call command.  After map is created its pinned to bpffs.  This makes
it possible to easily and dynamically (without rebuilding programs)
test various corner cases related to map creation.

Map type names are taken from bpftool's array used for printing.
In general these days we try to make use of libbpf type names, but
there are no map type names in libbpf as of today.

As with most features I add the motivation is testing (offloads) :)

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Jakub Kicinski
2018-10-15 16:30:36 -07:00
committed by Alexei Starovoitov
parent 2f1d774f7d
commit 0b592b5a01
6 changed files with 183 additions and 6 deletions

View File

@@ -15,13 +15,15 @@ SYNOPSIS
*OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-f** | **--bpffs** } }
*COMMANDS* :=
{ **show** | **list** | **dump** | **update** | **lookup** | **getnext** | **delete**
| **pin** | **help** }
{ **show** | **list** | **create** | **dump** | **update** | **lookup** | **getnext**
| **delete** | **pin** | **help** }
MAP COMMANDS
=============
| **bpftool** **map { show | list }** [*MAP*]
| **bpftool** **map create** *FILE* **type** *TYPE* **key** *KEY_SIZE* **value** *VALUE_SIZE* \
| **entries** *MAX_ENTRIES* **name** *NAME* [**flags** *FLAGS*] [**dev** *NAME*]
| **bpftool** **map dump** *MAP*
| **bpftool** **map update** *MAP* **key** *DATA* **value** *VALUE* [*UPDATE_FLAGS*]
| **bpftool** **map lookup** *MAP* **key** *DATA*
@@ -36,6 +38,11 @@ MAP COMMANDS
| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* }
| *VALUE* := { *DATA* | *MAP* | *PROG* }
| *UPDATE_FLAGS* := { **any** | **exist** | **noexist** }
| *TYPE* := { **hash** | **array** | **prog_array** | **perf_event_array** | **percpu_hash**
| | **percpu_array** | **stack_trace** | **cgroup_array** | **lru_hash**
| | **lru_percpu_hash** | **lpm_trie** | **array_of_maps** | **hash_of_maps**
| | **devmap** | **sockmap** | **cpumap** | **xskmap** | **sockhash**
| | **cgroup_storage** | **reuseport_sockarray** | **percpu_cgroup_storage** }
DESCRIPTION
===========
@@ -47,6 +54,10 @@ DESCRIPTION
Output will start with map ID followed by map type and
zero or more named attributes (depending on kernel version).
**bpftool map create** *FILE* **type** *TYPE* **key** *KEY_SIZE* **value** *VALUE_SIZE* **entries** *MAX_ENTRIES* **name** *NAME* [**flags** *FLAGS*] [**dev** *NAME*]
Create a new map with given parameters and pin it to *bpffs*
as *FILE*.
**bpftool map dump** *MAP*
Dump all entries in a given *MAP*.