On Tue, Oct 22, 2019 at 01:37:25PM +0200, Jakub Sitnicki wrote: > This patch set is a follow up on a suggestion from LPC '19 discussions to > make SOCKMAP (or a new map type derived from it) a generic type for storing > established as well as listening sockets. > > We found ourselves in need of a map type that keeps references to listening > sockets when working on making the socket lookup programmable, aka BPF > inet_lookup [1]. Initially we repurposed REUSEPORT_SOCKARRAY but found it > problematic to extend due to being tightly coupled with reuseport > logic (see slides [2]). > So we've turned our attention to SOCKMAP instead. > > As it turns out the changes needed to make SOCKMAP suitable for storing > listening sockets are self-contained and have use outside of programming > the socket lookup. Hence this patch set. > > With these patches SOCKMAP can be used in SK_REUSEPORT BPF programs as a > drop-in replacement for REUSEPORT_SOCKARRAY for TCP. This can hopefully > lead to code consolidation between the two map types in the future. What is the plan for UDP support in sockmap? > > Having said that, the main intention here is to lay groundwork for using > SOCKMAP in the next iteration of programmable socket lookup patches. What may be the minimal to get only lookup work for UDP sockmap? .close() and .unhash()? > > I'm looking for feedback if there's anything fundamentally wrong with > extending SOCKMAP map type like this that I might have missed. > > Thanks, > Jakub > > [1] https://lore.kernel.org/bpf/20190828072250.29828-1-jakub@xxxxxxxxxxxxxx/ > [2] https://urldefense.proofpoint.com/v2/url?u=https-3A__linuxplumbersconf.org_event_4_contributions_487_attachments_238_417_Programmable-5Fsocket-5Flookup-5FLPC-5F19.pdf&d=DwIDAg&c=5VD0RTtNlTh3ycd41b3MUw&r=VQnoQ7LvghIj0gVEaiQSUw&m=Y-Ap1QuRBsqsu8gATb1wH3rPT89No2mam2qINt1BGDI&s=_sfXVfJhB2eR7znE7-WBk660dQXIBxuDLRi7jvXVpsg&e= > > > Jakub Sitnicki (5): > bpf, sockmap: Let BPF helpers use lookup operation on SOCKMAP > bpf, sockmap: Allow inserting listening TCP sockets into SOCKMAP > bpf, sockmap: Don't let child socket inherit psock or its ops on copy > bpf: Allow selecting reuseport socket from a SOCKMAP > selftests/bpf: Extend SK_REUSEPORT tests to cover SOCKMAP > > kernel/bpf/verifier.c | 6 +- > net/core/sock_map.c | 11 +- > net/ipv4/tcp_bpf.c | 30 ++++ > tools/testing/selftests/bpf/Makefile | 7 +- > .../selftests/bpf/test_select_reuseport.c | 141 ++++++++++++++---- > .../selftests/bpf/test_select_reuseport.sh | 14 ++ > 6 files changed, 173 insertions(+), 36 deletions(-) > create mode 100755 tools/testing/selftests/bpf/test_select_reuseport.sh > > -- > 2.20.1 >
