Jakub Sitnicki wrote:
> On Wed, Jan 24, 2024 at 10:54 AM -08, John Fastabend wrote:
> > Sendmsg path with multiple buffers is slightly different from a single
> > send in how we have to handle and walk the sg when doing pops. Lets
> > ensure this walk is correct.
> >
> > Signed-off-by: John Fastabend <john.fastabend@xxxxxxxxx>
> > ---
> > .../bpf/prog_tests/sockmap_helpers.h | 8 +++
> > .../bpf/prog_tests/sockmap_msg_helpers.c | 53 +++++++++++++++++++
> > 2 files changed, 61 insertions(+)
> >
> > diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_helpers.h b/tools/testing/selftests/bpf/prog_tests/sockmap_helpers.h
> > index 781cbdf01d7b..4d8d24482032 100644
> > --- a/tools/testing/selftests/bpf/prog_tests/sockmap_helpers.h
> > +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_helpers.h
> > @@ -103,6 +103,14 @@
> > __ret; \
> > })
> >
> > +#define xsendmsg(fd, msg, flags) \
> > + ({ \
> > + ssize_t __ret = sendmsg((fd), (msg), (flags)); \
> > + if (__ret == -1) \
> > + FAIL_ERRNO("sendmsg"); \
> > + __ret; \
> > + })
> > +
> > #define xrecv_nonblock(fd, buf, len, flags) \
> > ({ \
> > ssize_t __ret = recv_timeout((fd), (buf), (len), (flags), \
> > diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_msg_helpers.c b/tools/testing/selftests/bpf/prog_tests/sockmap_msg_helpers.c
> > index 9ffe02f45808..e5e618e84950 100644
> > --- a/tools/testing/selftests/bpf/prog_tests/sockmap_msg_helpers.c
> > +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_msg_helpers.c
> > @@ -52,6 +52,50 @@ static void pop_simple_send(struct msg_test_opts *opts, int start, int len)
> > ASSERT_OK(cmp, "pop cmp end bytes failed");
> > }
> >
> > +static void pop_complex_send(struct msg_test_opts *opts, int start, int len)
> > +{
> > + struct test_sockmap_msg_helpers *skel = opts->skel;
> > + char buf[] = "abcdefghijklmnopqrstuvwxyz";
> > + size_t sent, recv, total = 0;
> > + struct msghdr msg = {0};
> > + struct iovec iov[15];
> > + char *recvbuf;
> > + int i;
> > +
> > + for (i = 0; i < 15; i++) {
>
> Always nice to use ARRAY_SIZE.
Agree will do.
>
> > + iov[i].iov_base = buf;
> > + iov[i].iov_len = sizeof(buf);
> > + total += sizeof(buf);
> > + }
> > +
> > + recvbuf = malloc(total);
> > + if (!recvbuf)
> > + FAIL("pop complex send malloc failure\n");
>
> 390 bytes, why not have it on stack?
Sure one less thing that could fail seems like a win.
