Re: [PATCH] tools/perf: Use perf_tool__init() to initialize default values in builtin trace

[Namhyung Kim <namhyung@kernel.org>]

On Tue, Feb 25, 2025 at 05:01:57PM +0530, Athira Rajeev wrote:
> Perf trace on perf.data fails as below:
> 
> 	./perf trace record -- sleep 1
> 	./perf trace -i perf.data
> 	perf: Segmentation fault
> 	Segmentation fault (core dumped)
> 
> Backtrace pointed to :
> 	?? ()
> 	perf_session.process_user_event ()
> 	reader.read_event ()
> 	perf_session.process_events ()
> 	cmd_trace ()
> 	run_builtin ()
> 	handle_internal_command ()
> 	main ()
> 
> Further debug pointed that, segmentation fault happens when
> trying to access id_index. Code snippet:
> 
> 	case PERF_RECORD_ID_INDEX:
> 		err = tool->id_index(session, event);
> 
> Since 'commit 15d4a6f41d72 ("perf tool: Remove
> perf_tool__fill_defaults()")', perf_tool__fill_defaults is
> removed. All tools are initialized using perf_tool__init()
> prior to use. But in builtin-trace, perf_tool__init is not
> used and hence the defaults are not initialized. Use
> perf_tool__init() in perf trace to handle the initialization.

Thanks for fixing this.  I can reproduce the problem and confirmed this
patch fixed it.

Thanks,
Namhyung

> 
> Reported-by: Tejas Manhas <Tejas.Manhas1@ibm.com>
> Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com>
> ---
>  tools/perf/builtin-trace.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
> index f55a8a6481f2..092c5f6404ba 100644
> --- a/tools/perf/builtin-trace.c
> +++ b/tools/perf/builtin-trace.c
> @@ -4589,6 +4589,7 @@ static int trace__replay(struct trace *trace)
>  	struct evsel *evsel;
>  	int err = -1;
>  
> +	perf_tool__init(&trace->tool, /*ordered_events=*/true);
>  	trace->tool.sample	  = trace__process_sample;
>  	trace->tool.mmap	  = perf_event__process_mmap;
>  	trace->tool.mmap2	  = perf_event__process_mmap2;
> -- 
> 2.43.5
>