Re: [PATCH v2 4/4] perf: Support perf -vv

[Jiri Olsa]

On Wed, Mar 28, 2018 at 10:00:32PM +0800, Jin, Yao wrote:
> 
> 
> On 3/28/2018 9:22 PM, Jiri Olsa wrote:
> > On Wed, Mar 28, 2018 at 10:57:08PM +0800, Jin Yao wrote:
> > > We keep having bug reports that when users build perf on their own,
> > > but they don't install some needed libraries such as libelf,
> > > libbfd/libibery.
> > > 
> > > The perf can build, but it is missing important functionality.
> > > 
> > > This patch provides a new option '-vv' which will print the
> > > compiled-in status of libraries.
> > > 
> > > The 'perf -vv' is equal to 'perf -version --build-options'.
> > > 
> > > For example:
> > > 
> > > $ ./perf -vv or ./perf -version --build-options
> > > perf version 4.13.rc5.gcb1183
> > >                   dwarf: [ on  ]
> > >      dwarf_getlocations: [ on  ]
> > >                   glibc: [ on  ]
> > >                    gtk2: [ on  ]
> > >                libaudit: [ OFF ]
> > >                  libbfd: [ on  ]
> > >                  libelf: [ on  ]
> > >                 libnuma: [ on  ]
> > > numa_num_possible_cpus: [ on  ]
> > >                 libperl: [ on  ]
> > >               libpython: [ on  ]
> > >                libslang: [ on  ]
> > >               libcrypto: [ on  ]
> > >               libunwind: [ on  ]
> > >      libdw-dwarf-unwind: [ on  ]
> > >                    zlib: [ on  ]
> > >                    lzma: [ on  ]
> > >               get_cpuid: [ on  ]
> > >                     bpf: [ on  ]
> > > [ on  ]: library is compiled-in
> > > [ OFF ]: library is disabled in make configuration
> > >           OR library is not installed in build environment
> > > 
> > > v2:
> > > ---
> > > Use a global variable version_verbose to count the number of 'v'.
> > > 
> > > Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
> > > ---
> > >   tools/perf/perf.c | 22 ++++++++++++++++++----
> > >   tools/perf/perf.h |  1 +
> > >   2 files changed, 19 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/tools/perf/perf.c b/tools/perf/perf.c
> > > index 1b3fc8e..355219e 100644
> > > --- a/tools/perf/perf.c
> > > +++ b/tools/perf/perf.c
> > > @@ -32,7 +32,7 @@
> > >   #include <linux/kernel.h>
> > >   const char perf_usage_string[] =
> > > -	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
> > > +	"perf [--version [--build-options]] [--help] [OPTIONS] COMMAND [ARGS]";
> > 
> > --build-options is 'perf version' option no?
> > 
> > jirka
> > 
> 
> Yes. Command-line something like:
> 
> perf --version --build-options or perf -v --build-options.
> 
> Is this usage string not correct? If so, I'd like to fix that.
> 
> "perf [--version [--build-options]] [--help] [OPTIONS] COMMAND [ARGS]";

ah I forgot that --version is in fact 'perf version'
now I see --build-options depends on --version.. ok ;-)

could you please also create Documentation/perf-version.txt,
now when it has option, we should document it

also please use the standard option parsing API we use in commands:

        argc = parse_options(argc, argv, record_options, record_usage,
                            PARSE_OPT_STOP_AT_NON_OPTION);

so we get standard error when the option is mangled,
unlinke now, when it's silent:

	[jolsa@krava perf]$ ./perf --version --buil
	perf version 4.16.rc6.gcc183d

thanks,
jirka