Re: [PATCH v3 1/2] bpf: add a longest prefix match trie map implementation
flat view
From: Alexei Starovoitov <hidden>
Date: 2017-01-14 16:56:14
On 1/14/17 4:17 AM, Daniel Mack wrote:
quoted hunk ↗ jump to hunk
+static struct bpf_map *trie_alloc(union bpf_attr *attr) +{ + size_t cost, cost_per_node; + struct lpm_trie *trie; + int ret; + + /* check sanity of attributes */ + if (attr->max_entries == 0 || + attr->map_flags != BPF_F_NO_PREALLOC || + attr->key_size < sizeof(struct bpf_lpm_trie_key) + 1 || + attr->key_size > sizeof(struct bpf_lpm_trie_key) + 256 || + attr->value_size == 0) + return ERR_PTR(-EINVAL);
could you also make it root only for now ?
Like we did for lru map:
if (lru && !capable(CAP_SYS_ADMIN))
/* LRU implementation is much complicated than other
* maps. Hence, limit to CAP_SYS_ADMIN for now.
*/
return ERR_PTR(-EPERM);
trie is not that complicated, but I think socket_filters
(the only unpriv prog type today) can live a release or
two without ability to use it.
In patch 2/2 there are some comments not in networking style:
+ /*
+ * Perform longest prefix-match on @key/@n_bits. That is,
As far as performance it has to be measured from datapath.
Like create tc+cls_bpf prog that does a dozen of trie lookups,
attach it to veth or tap and use
samples/pktgen/pktgen_bench_xmit_mode_netif_receive.sh
to send traffic into it.
Like: samples/bpf/test_cls_bpf.sh does.
Another alternative is to extend samples/bpf/map_perf_test
It has perf tests for most map types today (including lru)
and trie would be natural addition there.
I would prefer this latter option.
Thanks!