This new torture_sched_set_normal() function clamps the nice value at the MIN_NICE..MAX_NICE limits, splatting it these limits are exceeded. It then invokes sched_set_normal() to set the new value. This prevents more difficult-to-debug failures within the scheduler.
Signed-off-by: Paul E. McKenney <[email protected]> --- include/linux/torture.h | 1 + kernel/torture.c | 16 ++++++++++++++++ 2 files changed, 17 insertions(+) diff --git a/include/linux/torture.h b/include/linux/torture.h index d80f24ff69e3e1..66d2d444428aef 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -129,6 +129,7 @@ void _torture_stop_kthread(char *m, struct task_struct **tp); #else #define torture_preempt_schedule() do { } while (0) #endif +void torture_sched_set_normal(struct task_struct *t, int nice); #if IS_ENABLED(CONFIG_RCU_TORTURE_TEST) || IS_ENABLED(CONFIG_LOCK_TORTURE_TEST) || IS_ENABLED(CONFIG_HAZPTR_TORTURE_TEST) long torture_sched_setaffinity(pid_t pid, const struct cpumask *in_mask, bool dowarn); diff --git a/kernel/torture.c b/kernel/torture.c index 62c1ac77769424..77cb3589b19f9c 100644 --- a/kernel/torture.c +++ b/kernel/torture.c @@ -972,3 +972,19 @@ void _torture_stop_kthread(char *m, struct task_struct **tp) *tp = NULL; } EXPORT_SYMBOL_GPL(_torture_stop_kthread); + +/* + * Set the specified task's niceness value, saturating at limits. + * Saturating noisily, but saturating. + */ +void torture_sched_set_normal(struct task_struct *t, int nice) +{ + int realnice = nice; + + if (WARN_ON_ONCE(realnice > MAX_NICE)) + realnice = MAX_NICE; + if (WARN_ON_ONCE(realnice < MIN_NICE)) + realnice = MIN_NICE; + sched_set_normal(t, realnice); +} +EXPORT_SYMBOL_GPL(torture_sched_set_normal); -- 2.40.1
