Re: [PATCH v4 bpf-next 0/5] bpf: Add support for XDP programs in DEVMAP entries

On Mon, Jun 1, 2020 at 3:28 PM David Ahern [off-list ref] wrote:

On 6/1/20 3:12 PM, Alexei Starovoitov wrote:

quoted

In patch 5 I had to fix:
/data/users/ast/net-next/tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c:
In function ‘test_neg_xdp_devmap_helpers’:
/data/users/ast/net-next/tools/testing/selftests/bpf/test_progs.h:106:3:
warning: ‘duration’ may be used uninitialized in this function
[-Wmaybe-uninitialized]
  106 |   fprintf(stdout, "%s:PASS:%s %d nsec\n",   \
      |   ^~~~~~~
/data/users/ast/net-next/tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c:79:8:
note: ‘duration’ was declared here
   79 |  __u32 duration;

What compiler version? it compiles cleanly with ubuntu 20.04 and gcc
9.3. The other prog_tests are inconsistent with initializing it.

Do you have specific examples of inconsistencies? Seems like duration is:
1. either static variable, and thus zero-initialized;
2. is initialized explicitly at declaration;
3. is filled out with bpf_prog_test_run().

quoted

and that selftest is imo too primitive.

I focused the selftests on API changes introduced by this set - new
attach type, valid accesses to egress_ifindex and not allowing devmap
programs with xdp generic.

quoted

It's only loading progs and not executing them.
Could you please add prog_test_run to it?

I will look into it.