mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

tracing: Have function_graph selftest call cond_resched() 

When all kernel debugging is enabled (lockdep, KSAN, etc), the function
graph enabling and disabling can take several seconds to complete. The
function_graph selftest enables and disables function graph tracing
several times. With full debugging enabled, the soft lockup watchdog was
triggering because the selftest was running without ever scheduling.

Add cond_resched() throughout the test to make sure it does not trigger
the soft lockup detector.

Link: https://lkml.kernel.org/r/20230528051742.1325503-6-rostedt@goodmis.org

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Google) 2023-05-28 01:17:42 -04:00
parent ac9d2cb1d5
commit a2d910f022
1 changed files with 10 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
kernel/trace/trace_selftest.c
View File

@ -848,6 +848,12 @@ trace_selftest_startup_function_graph(struct tracer *trace,
}
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
/*
* These tests can take some time to run. Make sure on non PREEMPT
* kernels, we do not trigger the softlockup detector.
*/
cond_resched();
tracing_reset_online_cpus(&tr->array_buffer);
set_graph_array(tr);
@ -869,6 +875,8 @@ trace_selftest_startup_function_graph(struct tracer *trace,
if (ret)
goto out;
cond_resched();
ret = register_ftrace_graph(&fgraph_ops);
if (ret) {
warn_failed_init_tracer(trace, ret);
@ -891,6 +899,8 @@ trace_selftest_startup_function_graph(struct tracer *trace,
if (ret)
goto out;
cond_resched();
tracing_start();
if (!ret && !count) {