[PATCH] perf probe: Fix to delete multiple probe event

[PATCH] perf probe: Fix to delete multiple probe event

[Masami Hiramatsu]

Fix to delete multiple probe event with filter correctly.

When we put an event with multiple probes, perf-probe fails
to delete with filters. This comes from a failure to list
up the event name because of overwrapping its name.

To fix this issue, skip to list up the event which has
same name.

Without this patch:
  # perf probe -l \*
    probe_perf:map__map_ip (on perf_sample__fprintf_brstackoff:21@
    probe_perf:map__map_ip (on perf_sample__fprintf_brstackoff:25@
    probe_perf:map__map_ip (on append_inlines:12@util/machine.c in
    probe_perf:map__map_ip (on unwind_entry:19@util/machine.c in /
    probe_perf:map__map_ip (on map__map_ip@util/map.h in /home/mhi
    probe_perf:map__map_ip (on map__map_ip@util/map.h in /home/mhi
  # perf probe -d \*
  "*" does not hit any event.
    Error: Failed to delete events. Reason: No such file or directory (Code: -2)

With this:
  # perf probe -d \*
  Removed event: probe_perf:map__map_ip

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
 tools/perf/util/probe-file.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index 5003ba403345..c03a591d41a4 100644
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -206,6 +206,9 @@ static struct strlist *__probe_file__get_namelist(int fd, bool include_group)
 		} else
 			ret = strlist__add(sl, tev.event);
 		clear_probe_trace_event(&tev);
+		/* Skip if there is same name multi-probe event in the list */
+		if (ret == -EEXIST)
+			ret = 0;
 		if (ret < 0)
 			break;
 	}

Re: [PATCH] perf probe: Fix to delete multiple probe event

[Masami Hiramatsu]

On Tue,  3 Dec 2019 17:01:54 +0900
Masami Hiramatsu <mhiramat@kernel.org> wrote:

> Fix to delete multiple probe event with filter correctly.
> 
> When we put an event with multiple probes, perf-probe fails
> to delete with filters. This comes from a failure to list
> up the event name because of overwrapping its name.
> 
> To fix this issue, skip to list up the event which has
> same name.
> 
> Without this patch:
>   # perf probe -l \*
>     probe_perf:map__map_ip (on perf_sample__fprintf_brstackoff:21@
>     probe_perf:map__map_ip (on perf_sample__fprintf_brstackoff:25@
>     probe_perf:map__map_ip (on append_inlines:12@util/machine.c in
>     probe_perf:map__map_ip (on unwind_entry:19@util/machine.c in /
>     probe_perf:map__map_ip (on map__map_ip@util/map.h in /home/mhi
>     probe_perf:map__map_ip (on map__map_ip@util/map.h in /home/mhi
>   # perf probe -d \*
>   "*" does not hit any event.
>     Error: Failed to delete events. Reason: No such file or directory (Code: -2)
> 
> With this:
>   # perf probe -d \*
>   Removed event: probe_perf:map__map_ip
> 

Oops, I missed Fixed tag.

Fixes: 72363540c009 ("perf probe: Support multiprobe event")

Thanks,

> Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> ---
>  tools/perf/util/probe-file.c |    3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
> index 5003ba403345..c03a591d41a4 100644
> --- a/tools/perf/util/probe-file.c
> +++ b/tools/perf/util/probe-file.c
> @@ -206,6 +206,9 @@ static struct strlist *__probe_file__get_namelist(int fd, bool include_group)
>  		} else
>  			ret = strlist__add(sl, tev.event);
>  		clear_probe_trace_event(&tev);
> +		/* Skip if there is same name multi-probe event in the list */
> +		if (ret == -EEXIST)
> +			ret = 0;
>  		if (ret < 0)
>  			break;
>  	}
> 


-- 
Masami Hiramatsu <mhiramat@kernel.org>

Re: [PATCH] perf probe: Fix to delete multiple probe event

[Masami Hiramatsu]

Hi Arnaldo,

Could you pick this fix?

Sandipan, could you also test this?

Thank you,

On Wed, 4 Dec 2019 11:29:52 +0900
Masami Hiramatsu <mhiramat@kernel.org> wrote:

> On Tue,  3 Dec 2019 17:01:54 +0900
> Masami Hiramatsu <mhiramat@kernel.org> wrote:
> 
> > Fix to delete multiple probe event with filter correctly.
> > 
> > When we put an event with multiple probes, perf-probe fails
> > to delete with filters. This comes from a failure to list
> > up the event name because of overwrapping its name.
> > 
> > To fix this issue, skip to list up the event which has
> > same name.
> > 
> > Without this patch:
> >   # perf probe -l \*
> >     probe_perf:map__map_ip (on perf_sample__fprintf_brstackoff:21@
> >     probe_perf:map__map_ip (on perf_sample__fprintf_brstackoff:25@
> >     probe_perf:map__map_ip (on append_inlines:12@util/machine.c in
> >     probe_perf:map__map_ip (on unwind_entry:19@util/machine.c in /
> >     probe_perf:map__map_ip (on map__map_ip@util/map.h in /home/mhi
> >     probe_perf:map__map_ip (on map__map_ip@util/map.h in /home/mhi
> >   # perf probe -d \*
> >   "*" does not hit any event.
> >     Error: Failed to delete events. Reason: No such file or directory (Code: -2)
> > 
> > With this:
> >   # perf probe -d \*
> >   Removed event: probe_perf:map__map_ip
> > 
> 
> Oops, I missed Fixed tag.
> 
> Fixes: 72363540c009 ("perf probe: Support multiprobe event")
> 
> Thanks,	
> 
> > Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
> > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> > ---
> >  tools/perf/util/probe-file.c |    3 +++
> >  1 file changed, 3 insertions(+)
> > 
> > diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
> > index 5003ba403345..c03a591d41a4 100644
> > --- a/tools/perf/util/probe-file.c
> > +++ b/tools/perf/util/probe-file.c
> > @@ -206,6 +206,9 @@ static struct strlist *__probe_file__get_namelist(int fd, bool include_group)
> >  		} else
> >  			ret = strlist__add(sl, tev.event);
> >  		clear_probe_trace_event(&tev);
> > +		/* Skip if there is same name multi-probe event in the list */
> > +		if (ret == -EEXIST)
> > +			ret = 0;
> >  		if (ret < 0)
> >  			break;
> >  	}
> > 
> 
> 
> -- 
> Masami Hiramatsu <mhiramat@kernel.org>


-- 
Masami Hiramatsu <mhiramat@kernel.org>

Re: [PATCH] perf probe: Fix to delete multiple probe event

[Sandipan Das]

On 08/01/20 8:06 am, Masami Hiramatsu wrote:
> Hi Arnaldo,
> 
> Could you pick this fix?
> 
> Sandipan, could you also test this?
> 
[...]

Thanks for fixing this.

Tested-by: Sandipan Das <sandipan@linux.ibm.com>