Re: [PATCH v2 3/4] bpf tools: Improve libbpf error reporting

["Wangnan (F)" <wangnan0@huawei.com>]

On 2015/11/5 9:48, Wangnan (F) wrote:
>
>
> On 2015/11/5 6:01, Arnaldo Carvalho de Melo wrote:
>> Em Wed, Nov 04, 2015 at 02:25:58AM +0000, Wang Nan escreveu:
>>> In this patch, a series libbpf specific error numbers and
>>> libbpf_strerror() are created to help reporting error to caller.
>>> Functions are updated to pass correct error number through macro
>>> CHECK_ERR().
>>>
>>> All users of bpf_object__open{_buffer}() and bpf_program__title()
>>> in perf are modified accordingly.
>> So, before I get:
>>
>>    [root@zoo ~]# perf record -e /tmp/foo.o sleep 1
>>    event syntax error: '/tmp/foo.o'
>>                         \___ Invalid argument: Are you root and 
>> runing a CONFIG_BPF_SYSCALL kernel?
>>
>>    (add -v to see detail)
>>    Run 'perf list' for a list of valid events
>>
>>     Usage: perf record [<options>] [<command>]
>>        or: perf record [<options>] -- <command> [<options>]
>>
>>        -e, --event <event>   event selector. use 'perf list' to list 
>> available events
>>
>>
>> And now:
>>
>>    [root@zoo ~]# perf record -e /tmp/foo.o sleep 1
>>    event syntax error: '/tmp/foo.o'
>>                         \___ Unknown error 4006
>>
>>    (add -v to see detail)
>>    Run 'perf list' for a list of valid events
>>
>>     Usage: perf record [<options>] [<command>]
>>        or: perf record [<options>] -- <command> [<options>]
>>
>>        -e, --event <event>   event selector. use 'perf list' to list 
>> available events
>>    [root@zoo ~]#
>>
>> Can you please fix this? The relevant strerror() routine should know 
>> about the
>> errors it handles and produce an informative message.
>>
>> - Arnaldo
>>
>
> An libbpf related patches are losted because yesterday I didn't know
> your head.
>

Nothing losted...

You won't see this after 4/4. However, I can fix this "Unknown error 4006"
reporting in this patch.

Thank you.