On Wed, Aug 13, 2014 at 12:57 AM, Alexei Starovoitov <ast@xxxxxxxxxxxx> wrote: [...] > maps can have different types: hash, bloom filter, radix-tree, etc. > > The map is defined by: > . type > . max number of elements > . key size in bytes > . value size in bytes Can values be strings or byte arrays? How would user-level bpf read them? The two types of uses I'm thinking are: A. Constructing a custom string in kernel-context, and using that as the value. Eg, a truncated filename, or a dotted quad IP address, or the raw contents of a packet. B. I have a pointer to an existing buffer or string, eg a filename, that will likely be around for some time (>1s). Instead of the value storing the string, it could just be a ptr, so long as user-level bpf has a way to read it. Also, can keys be strings? I'd ask about multiple keys, but if they can be a string, I can delimit in the key (eg, "PID:filename"). Thanks, Brendan -- http://www.brendangregg.com -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
