Re: [PATCH v1 2/3] perf version: Print the status of compiled-in libraries

[Jin, Yao]

On 3/27/2018 8:56 PM, Jiri Olsa wrote:
On Tue, Mar 27, 2018 at 09:44:23AM +0800, Jin, Yao wrote:


On 3/26/2018 5:39 PM, Jiri Olsa wrote:
On Tue, Mar 27, 2018 at 12:07:03AM +0800, Jin Yao wrote:
This patch checks the values passed by CFLAGS (-DXXX) and then
print the status of libraries.

For example, if HAVE_DWARF_SUPPORT is defined, that means the
library "dwarf" is compiled-in. The patch will print the status
"on" for this library.

Signed-off-by: Jin Yao <yao....@linux.intel.com>
---
   tools/perf/builtin-version.c | 125 
+++++++++++++++++++++++++++++++++++++++++++
   tools/perf/builtin.h         |   1 +
   2 files changed, 126 insertions(+)

diff --git a/tools/perf/builtin-version.c b/tools/perf/builtin-version.c
index 37019c5..90a0a7f 100644
--- a/tools/perf/builtin-version.c
+++ b/tools/perf/builtin-version.c
@@ -9,3 +9,128 @@ int cmd_version(int argc __maybe_unused, const char **argv 
__maybe_unused)
        printf("perf version %s\n", perf_version_string);
        return 0;
   }
+
+static void status_print(const char *name, const char *status)
+{
+       printf("%22s: [ %3s ]\n", name, status);
+}
+
+static void library_status(void)
+{
+#ifdef HAVE_DWARF_SUPPORT
+       status_print("dwarf", "on");
+#else
+       status_print("dwarf", "off");
+#endif

could this and all those below be in some generic macro?

#define STATUS(__d, __m)                \
#ifdef __d                              \
        status_print(#__m, "on");     \
#else                                   \
        status_print(#__m, "OFF");    \
#endif

STATUS(HAVE_DWARF_SUPPORT, dwarf)



Hi Jiri,

I have tried this macro definition, but unfortunately the compilation is
failed.

error: '#' is not followed by a macro parameter
  #define STATUS(__d, __m)  \

I just guess the '#' in #ifdef confuses the gcc. Looks we can't define
#ifdef/#endif block in a macro.


ah crap.. right ;-) how about we take the IS_BUILTIN thingie
from include/linux/kconfig.h and use it as in attached test
change.. it gives me:

        [jolsa@krava perf]$ ./perf version
        perf version 4.16.rc6.g1ee9a60
                         dwarf: [  on ]
                         krava: [ OFF ]

we could put those macros into tools/include/tools/config.h, Arnaldo?
together with the comments from kconfig.h that I cut out..

thanks,
jirka


---
diff --git a/tools/perf/builtin-version.c b/tools/perf/builtin-version.c
index 1fe458792cc1..b392f9e80fd0 100644
--- a/tools/perf/builtin-version.c
+++ b/tools/perf/builtin-version.c
@@ -6,8 +6,33 @@
  
  int version_verbose;
  
+
+#define __ARG_PLACEHOLDER_1 0,
+#define __take_second_arg(__ignored, val, ...) val
+
+#define __is_defined(x)                 ___is_defined(x)
+#define ___is_defined(val)              ____is_defined(__ARG_PLACEHOLDER_##val)
+#define ____is_defined(arg1_or_junk)    __take_second_arg(arg1_or_junk 1, 0)
+
+#define IS_BUILTIN(option) __is_defined(option)
+
+
+static void status_print(const char *name, const char *status)
+{
+       printf("%22s: [ %3s ]\n", name, status);
+}
+
  int cmd_version(int argc __maybe_unused, const char **argv __maybe_unused)
  {
        printf("perf version %s\n", perf_version_string);
+
+#define STATUS(__d, __m)                       \
+       if (IS_BUILTIN(__d))                    \
+               status_print(#__m, "on");     \
+       else                                    \
+               status_print(#__m, "OFF");
+
+       STATUS(HAVE_DWARF_SUPPORT, dwarf)
+       STATUS(HAVE_KRAVA_SUPPORT, krava)
        return 0;
  }


Hi Jiri,

It looks we need to copy the IS_BUILTIN and associated macro definitions 
to a common header file.

I guess you will post this patch if Arnaldo agree with this idea, right?

I plan to post v2 of this patch series after this 'IS_BUILTIN' patch 
gets merged.

Thanks
Jin Yao