| Message ID | 20181130145622.26334-1-anders.roxell@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] kernel/trace: fix watchdog soft lockup | expand |
On Fri, 30 Nov 2018 15:56:22 +0100 Anders Roxell <anders.roxell@linaro.org> wrote: > When building a allmodconfig kernel for arm64 and boot that in qemu, > CONFIG_FTRACE_STARTUP_TEST gets enabled and that takes time so the > watchdog expires and prints out a message like this: > 'watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1]' > Depending on what the what test gets called from init_trace_selftests() > it stays minutes in the loop. > Rework so that function cond_resched() gets called in the > init_trace_selftests loop. > This looks fine to me. Should it be marked for stable, and pushed into this release cycle, or wait till the next merge window? -- Steve > Co-developed-by: Arnd Bergmann <arnd@arndb.de> > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > Signed-off-by: Anders Roxell <anders.roxell@linaro.org> > --- > kernel/trace/trace.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index 5706599ed534..109becbc81ca 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -1547,6 +1547,10 @@ static __init int init_trace_selftests(void) > pr_info("Running postponed tracer tests:\n"); > > list_for_each_entry_safe(p, n, &postponed_selftests, list) { > + /* This loop can take minutes when sanitizers are enabled, so > + * lets make sure we allow RCU processing. > + */ > + cond_resched(); > ret = run_tracer_selftest(p->type); > /* If the test fails, then warn and remove from available_tracers */ > if (ret < 0) {
On Fri, 30 Nov 2018 at 16:18, Steven Rostedt <rostedt@goodmis.org> wrote: > > On Fri, 30 Nov 2018 15:56:22 +0100 > Anders Roxell <anders.roxell@linaro.org> wrote: > > > When building a allmodconfig kernel for arm64 and boot that in qemu, > > CONFIG_FTRACE_STARTUP_TEST gets enabled and that takes time so the > > watchdog expires and prints out a message like this: > > 'watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1]' > > Depending on what the what test gets called from init_trace_selftests() > > it stays minutes in the loop. > > Rework so that function cond_resched() gets called in the > > init_trace_selftests loop. > > > > This looks fine to me. Should it be marked for stable, and pushed into > this release cycle, or wait till the next merge window? Steve, I'm sorry for the late reply and no its not urgent. Maybe it can make it into v5.2 ? Cheers, Anders > > -- Steve > > > Co-developed-by: Arnd Bergmann <arnd@arndb.de> > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > > Signed-off-by: Anders Roxell <anders.roxell@linaro.org> > > --- > > kernel/trace/trace.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > > index 5706599ed534..109becbc81ca 100644 > > --- a/kernel/trace/trace.c > > +++ b/kernel/trace/trace.c > > @@ -1547,6 +1547,10 @@ static __init int init_trace_selftests(void) > > pr_info("Running postponed tracer tests:\n"); > > > > list_for_each_entry_safe(p, n, &postponed_selftests, list) { > > + /* This loop can take minutes when sanitizers are enabled, so > > + * lets make sure we allow RCU processing. > > + */ > > + cond_resched(); > > ret = run_tracer_selftest(p->type); > > /* If the test fails, then warn and remove from available_tracers */ > > if (ret < 0) { >
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 5706599ed534..109becbc81ca 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1547,6 +1547,10 @@ static __init int init_trace_selftests(void) pr_info("Running postponed tracer tests:\n"); list_for_each_entry_safe(p, n, &postponed_selftests, list) { + /* This loop can take minutes when sanitizers are enabled, so + * lets make sure we allow RCU processing. + */ + cond_resched(); ret = run_tracer_selftest(p->type); /* If the test fails, then warn and remove from available_tracers */ if (ret < 0) {