Re: [RFC PATCH 05/13] bpf tools: Save engine type in bpf_program

From: pi3orama
Date: Wed Apr 20 2016 - 15:30:16 EST




发自我的 iPhone

> 在 2016年4月21日,上午3:23,Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> 写道:
>
> Em Wed, Apr 20, 2016 at 06:01:45PM +0000, Wang Nan escreveu:
>>

[SNIP]

>>
>> + if (prog->engine == ENGINE_UNKNOWN)
>> + prog->engine = ENGINE_KBPF;
>> + if (prog->engine != ENGINE_KBPF)
>
> else if (prog->engine != ENGINE_KBPF)
>
> Nitpicking a bit :-)
>

We set it to ENGINE_KBPF in previous "if",
so can't use "else".

Do this because I want the engine is KBPF
if not explicitly set to UNPF.

Thank you.

>> + return -EINVAL;
>> +
>> if (prog->instances.nr < 0 || !prog->instances.array) {
>> if (prog->preprocessor) {
>> pr_warning("Internal error: can't load program '%s'\n",
>> @@ -1318,6 +1330,34 @@ int bpf_program__nth_fd(struct bpf_program *prog, int n)
>> return fd;
>> }
>>
>> +#ifdef HAVE_UBPF_SUPPORT
>> +int bpf_program__set_ubpf(struct bpf_program *prog)
>> +{
>> + if (prog->engine != ENGINE_UNKNOWN) {
>> + pr_warning("Can't set program %s to ubpf\n",
>> + prog->section_name);
>> + return -EINVAL;
>> + }
>> + prog->engine = ENGINE_UBPF;
>> + return 0;
>> +}
>> +
>> +bool bpf_program__is_ubpf(struct bpf_program *prog)
>> +{
>> + return prog->engine == ENGINE_UBPF;
>> +}
>> +#else
>> +int bpf_program__set_ubpf(struct bpf_program *prog __maybe_unused)
>> +{
>> + return -LIBBPF_ERRNO__NOUBPF;
>> +}
>> +
>> +bool bpf_program__is_ubpf(struct bpf_program *prog __maybe_unused)
>> +{
>> + return false;
>> +}
>> +#endif
>> +
>> int bpf_map__get_fd(struct bpf_map *map)
>> {
>> if (!map)
>> diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
>> index a51594c..f6965ce 100644
>> --- a/tools/lib/bpf/libbpf.h
>> +++ b/tools/lib/bpf/libbpf.h
>> @@ -26,6 +26,7 @@ enum libbpf_errno {
>> LIBBPF_ERRNO__VERIFY, /* Kernel verifier blocks program loading */
>> LIBBPF_ERRNO__PROG2BIG, /* Program too big */
>> LIBBPF_ERRNO__KVER, /* Incorrect kernel version */
>> + LIBBPF_ERRNO__NOUBPF, /* UBPF support is not compiled */
>> __LIBBPF_ERRNO__END,
>> };
>>
>> @@ -86,6 +87,9 @@ int bpf_program__get_private(struct bpf_program *prog,
>>
>> const char *bpf_program__title(struct bpf_program *prog, bool needs_copy);
>>
>> +int bpf_program__set_ubpf(struct bpf_program *prog);
>> +bool bpf_program__is_ubpf(struct bpf_program *prog);
>> +
>> int bpf_program__fd(struct bpf_program *prog);
>>
>> struct bpf_insn;
>> --
>> 1.8.3.4