[PATCH] markers: fix missing modpost entry in Module.markers

[Lai Jiangshan]

commit d35cb360c29956510b2fe1a953bd4968536f7216 brought a bug.
marker points compiled in vmlinux are missing in Module.markers.

# cat Module.markers
subsystem_event samples/markers/marker-example  integer %d string %s
subsystem_eventb        samples/markers/marker-example

# stap -e 'probe kernel.mark("core_marker_format"){} '
semantic error: no match while resolving probe point kernel.mark("core_marker_format")
semantic error: no probes found
Pass 2: analysis failed.  Try again with more '-v' (verbose) options.

This patch revert a part of d35cb360c29956510b2fe1a953bd4968536f7216.
Other parts have fixed duplicate modpost entry bug.


Signed-off-by: Lai Jiangshan <laijs@...>
---
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 418cd7d..3509142 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -1992,8 +1992,7 @@ static void read_markers(const char *fname)
  mod->skip = 1;
  }
 
- if (!mod->skip)
- add_marker(mod, marker, fmt);
+ add_marker(mod, marker, fmt);
  }
  return;
 fail:

[KOSAKI Motohiro]

Hi Lai

Have you seen "Markers in (non-module) kernel code?" thread?
I think this patch and that patch treat the same issue.

In addition, I think mathieu's patch is better.
So, Could I hear your opinition for that?

>
> commit d35cb360c29956510b2fe1a953bd4968536f7216 brought a bug.
> marker points compiled in vmlinux are missing in Module.markers.
>
> # cat Module.markers
> subsystem_event samples/markers/marker-example  integer %d string %s
> subsystem_eventb        samples/markers/marker-example
>
> # stap -e 'probe kernel.mark("core_marker_format"){} '
> semantic error: no match while resolving probe point kernel.mark("core_marker_format")
> semantic error: no probes found
> Pass 2: analysis failed.  Try again with more '-v' (verbose) options.
>
> This patch revert a part of d35cb360c29956510b2fe1a953bd4968536f7216.
> Other parts have fixed duplicate modpost entry bug.
>
>
> Signed-off-by: Lai Jiangshan <laijs@...>
> ---
> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
> index 418cd7d..3509142 100644
> --- a/scripts/mod/modpost.c
> +++ b/scripts/mod/modpost.c
> @@ -1992,8 +1992,7 @@ static void read_markers(const char *fname)
>   mod->skip = 1;
>   }
>  
> - if (!mod->skip)
> - add_marker(mod, marker, fmt);
> + add_marker(mod, marker, fmt);
>   }
>   return;
>  fail:
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@...
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/

[Lai Jiangshan]

KOSAKI Motohiro wrote:
> Hi Lai
>
> Have you seen "Markers in (non-module) kernel code?" thread?
> I think this patch and that patch treat the same issue.
>

I didn't notice that thread.

> In addition, I think mathieu's patch is better.

I greed with you, Mathieu's patch is better.

Thanks.

> So, Could I hear your opinition for that?
>
>
>> commit d35cb360c29956510b2fe1a953bd4968536f7216 brought a bug.
>> marker points compiled in vmlinux are missing in Module.markers.
>>
>> # cat Module.markers
>> subsystem_event samples/markers/marker-example  integer %d string %s
>> subsystem_eventb        samples/markers/marker-example
>>
>> # stap -e 'probe kernel.mark("core_marker_format"){} '
>> semantic error: no match while resolving probe point kernel.mark("core_marker_format")
>> semantic error: no probes found
>> Pass 2: analysis failed.  Try again with more '-v' (verbose) options.
>>
>> This patch revert a part of d35cb360c29956510b2fe1a953bd4968536f7216.
>> Other parts have fixed duplicate modpost entry bug.
>>
>>
>> Signed-off-by: Lai Jiangshan <laijs@...>
>> ---
>> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
>> index 418cd7d..3509142 100644
>> --- a/scripts/mod/modpost.c
>> +++ b/scripts/mod/modpost.c
>> @@ -1992,8 +1992,7 @@ static void read_markers(const char *fname)
>>   mod->skip = 1;
>>   }
>>  
>> - if (!mod->skip)
>> - add_marker(mod, marker, fmt);
>> + add_marker(mod, marker, fmt);
>>   }
>>   return;
>>  fail:
>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@...
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>
>
>
>
>
>

[Mathieu Desnoyers]

Hi Lai,

I tried to fix it in a way that would still not duplicate marker
entries, which is what the patch we are trying to repair was supposed to
do. The patch you propose here seems to go back to the old behavior
where we can have duplicate marker entries. I did not verify extensively
that my new patch does not duplicate marker entries though, but I tried
to follow the logic of your original patch.

Mathieu

* Lai Jiangshan (laijs@...) wrote:

> KOSAKI Motohiro wrote:
> > Hi Lai
> >
> > Have you seen "Markers in (non-module) kernel code?" thread?
> > I think this patch and that patch treat the same issue.
> >
>
> I didn't notice that thread.
>
> > In addition, I think mathieu's patch is better.
>
> I greed with you, Mathieu's patch is better.
>
> Thanks.
>
> > So, Could I hear your opinition for that?
> >
> >
> >> commit d35cb360c29956510b2fe1a953bd4968536f7216 brought a bug.
> >> marker points compiled in vmlinux are missing in Module.markers.
> >>
> >> # cat Module.markers
> >> subsystem_event samples/markers/marker-example  integer %d string %s
> >> subsystem_eventb        samples/markers/marker-example
> >>
> >> # stap -e 'probe kernel.mark("core_marker_format"){} '
> >> semantic error: no match while resolving probe point kernel.mark("core_marker_format")
> >> semantic error: no probes found
> >> Pass 2: analysis failed.  Try again with more '-v' (verbose) options.
> >>
> >> This patch revert a part of d35cb360c29956510b2fe1a953bd4968536f7216.
> >> Other parts have fixed duplicate modpost entry bug.
> >>
> >>
> >> Signed-off-by: Lai Jiangshan <laijs@...>
> >> ---
> >> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
> >> index 418cd7d..3509142 100644
> >> --- a/scripts/mod/modpost.c
> >> +++ b/scripts/mod/modpost.c
> >> @@ -1992,8 +1992,7 @@ static void read_markers(const char *fname)
> >>   mod->skip = 1;
> >>   }
> >>  
> >> - if (!mod->skip)
> >> - add_marker(mod, marker, fmt);
> >> + add_marker(mod, marker, fmt);
> >>   }
> >>   return;
> >>  fail:
> >>
> >>
> >> --
> >> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> >> the body of a message to majordomo@...
> >> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> >> Please read the FAQ at  http://www.tux.org/lkml/
> >
> >
> >
> >
> >
> >
>
>

--
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68