rtla: Fix segmentation fault when failing to enable -t

rtla osnoise and timerlat are causing a segmentation fault when running
with the --trace option on a kernel that does not support multiple
instances. For example:

    [root@f34 rtla]# rtla osnoise top -t
    failed to enable the tracer osnoise
    Could not enable osnoiser tracer for tracing
    Failed to enable the trace instance
    Segmentation fault (core dumped)

This error happens because the exit code of the tools is trying
to destroy the trace instance that failed to be created.

Make osnoise_destroy_tool() aware of possible NULL osnoise_tool *,
and do not attempt to destroy it. This also simplifies the exit code.

Link: https://lkml.kernel.org/r/5660a2b6bf66c2655842360f2d7f6b48db5dba23.1644327249.git.bristot@kernel.org
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode")
Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode")
Fixes: a828cd18bc4a ("rtla: Add timerlat tool and timelart top mode")
Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode")
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

diff --git a/tools/tracing/rtla/src/osnoise.c b/tools/tracing/rtla/src/osnoise.c
index 7b73d1eccd0e3d373e56b42ba873e87a7a95ce22..5648f9252e580870a4b6fcc72ff09debb34405f8 100644 (file)
--- a/tools/tracing/rtla/src/osnoise.c
+++ b/tools/tracing/rtla/src/osnoise.c
@@ -750,6 +750,9 @@ void osnoise_put_context(struct osnoise_context *context)
  */
 void osnoise_destroy_tool(struct osnoise_tool *top)
 {
+       if (!top)
+               return;
+
        trace_instance_destroy(&top->trace);
 
        if (top->context)

diff --git a/tools/tracing/rtla/src/osnoise_hist.c b/tools/tracing/rtla/src/osnoise_hist.c
index 180fcbe423cd1dd3b9d94d2a5e387fbd7a7ad365..1f0b7fce55cf68d3a2e1652ebf2c9bb9ba6b9070 100644 (file)
--- a/tools/tracing/rtla/src/osnoise_hist.c
+++ b/tools/tracing/rtla/src/osnoise_hist.c
@@ -701,9 +701,9 @@ osnoise_hist_set_signals(struct osnoise_hist_params *params)
 int osnoise_hist_main(int argc, char *argv[])
 {
        struct osnoise_hist_params *params;
+       struct osnoise_tool *record = NULL;
+       struct osnoise_tool *tool = NULL;
        struct trace_instance *trace;
-       struct osnoise_tool *record;
-       struct osnoise_tool *tool;
        int return_value = 1;
        int retval;
 
@@ -792,9 +792,8 @@ int osnoise_hist_main(int argc, char *argv[])
 out_hist:
        osnoise_free_histogram(tool->data);
 out_destroy:
+       osnoise_destroy_tool(record);
        osnoise_destroy_tool(tool);
-       if (params->trace_output)
-               osnoise_destroy_tool(record);
        free(params);
 out_exit:
        exit(return_value);

diff --git a/tools/tracing/rtla/src/osnoise_top.c b/tools/tracing/rtla/src/osnoise_top.c
index 332b2ac205fc4383a820a4e40b58916a3127e34c..c67dc28ef716af5e68769e51829a3908cfae7030 100644 (file)
--- a/tools/tracing/rtla/src/osnoise_top.c
+++ b/tools/tracing/rtla/src/osnoise_top.c
@@ -483,9 +483,9 @@ static void osnoise_top_set_signals(struct osnoise_top_params *params)
 int osnoise_top_main(int argc, char **argv)
 {
        struct osnoise_top_params *params;
+       struct osnoise_tool *record = NULL;
+       struct osnoise_tool *tool = NULL;
        struct trace_instance *trace;
-       struct osnoise_tool *record;
-       struct osnoise_tool *tool;
        int return_value = 1;
        int retval;
 
@@ -571,9 +571,8 @@ int osnoise_top_main(int argc, char **argv)
 
 out_top:
        osnoise_free_top(tool->data);
+       osnoise_destroy_tool(record);
        osnoise_destroy_tool(tool);
-       if (params->trace_output)
-               osnoise_destroy_tool(record);
 out_exit:
        exit(return_value);
 }

diff --git a/tools/tracing/rtla/src/timerlat_hist.c b/tools/tracing/rtla/src/timerlat_hist.c
index 235f9620ef3d6ccb4663f0ef2285d31a00a24cfa..436a799f9adf9fad3a436578e4fe3eb09d29aa9e 100644 (file)
--- a/tools/tracing/rtla/src/timerlat_hist.c
+++ b/tools/tracing/rtla/src/timerlat_hist.c
@@ -729,9 +729,9 @@ timerlat_hist_set_signals(struct timerlat_hist_params *params)
 int timerlat_hist_main(int argc, char *argv[])
 {
        struct timerlat_hist_params *params;
+       struct osnoise_tool *record = NULL;
+       struct osnoise_tool *tool = NULL;
        struct trace_instance *trace;
-       struct osnoise_tool *record;
-       struct osnoise_tool *tool;
        int return_value = 1;
        int retval;
 
@@ -813,9 +813,8 @@ int timerlat_hist_main(int argc, char *argv[])
 
 out_hist:
        timerlat_free_histogram(tool->data);
+       osnoise_destroy_tool(record);
        osnoise_destroy_tool(tool);
-       if (params->trace_output)
-               osnoise_destroy_tool(record);
        free(params);
 out_exit:
        exit(return_value);

diff --git a/tools/tracing/rtla/src/timerlat_top.c b/tools/tracing/rtla/src/timerlat_top.c
index 1ebd5291539cb5ea8221cf71b8b0a84d6b2551d7..d4187f6534ed880c64939079d3c50617369c1997 100644 (file)
--- a/tools/tracing/rtla/src/timerlat_top.c
+++ b/tools/tracing/rtla/src/timerlat_top.c
@@ -521,9 +521,9 @@ timerlat_top_set_signals(struct timerlat_top_params *params)
 int timerlat_top_main(int argc, char *argv[])
 {
        struct timerlat_top_params *params;
+       struct osnoise_tool *record = NULL;
+       struct osnoise_tool *top = NULL;
        struct trace_instance *trace;
-       struct osnoise_tool *record;
-       struct osnoise_tool *top;
        int return_value = 1;
        int retval;
 
@@ -609,9 +609,8 @@ int timerlat_top_main(int argc, char *argv[])
 
 out_top:
        timerlat_free_top(top->data);
+       osnoise_destroy_tool(record);
        osnoise_destroy_tool(top);
-       if (params->trace_output)
-               osnoise_destroy_tool(record);
        free(params);
 out_exit:
        exit(return_value);