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

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

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.

Today I'd like to merge my two patchsets and send them to you together.

Thank you.