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| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2017-04-28 19:20:28 +0200 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2017-06-08 17:25:35 +0200 |
| commit | 59d80fd8351b7b9a5dc7bbfa8bc4ca19f6ff3dad (patch) | |
| tree | 5397e69e899ba8bb4acde750532fbf2f0f4be0d2 | |
| parent | rcu: Add preemptibility checks in rcu_sched_qs() and rcu_bh_qs() (diff) | |
| download | linux-59d80fd8351b7b9a5dc7bbfa8bc4ca19f6ff3dad.tar.xz linux-59d80fd8351b7b9a5dc7bbfa8bc4ca19f6ff3dad.zip | |
rcu: Print out rcupdate.c non-default boot-time settings
This commit adds a rcupdate_announce_bootup_oddness() function to
print out non-default values of significant kernel boot parameter
settings to aid in debugging.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| -rw-r--r-- | include/linux/rcupdate.h | 1 | ||||
| -rw-r--r-- | kernel/rcu/tree_plugin.h | 1 | ||||
| -rw-r--r-- | kernel/rcu/update.c | 42 |
3 files changed, 43 insertions, 1 deletions
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index e1e5d002fdb9..393e461d3ea8 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -76,6 +76,7 @@ bool rcu_gp_is_normal(void); /* Internal RCU use. */ bool rcu_gp_is_expedited(void); /* Internal RCU use. */ void rcu_expedite_gp(void); void rcu_unexpedite_gp(void); +void rcupdate_announce_bootup_oddness(void); #endif /* #else #ifdef CONFIG_TINY_RCU */ enum rcutorture_type { diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 3b432fa4c45b..eb5ebdce25ff 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -92,6 +92,7 @@ static void __init rcu_bootup_announce_oddness(void) pr_info("\tRCU restricting CPUs from NR_CPUS=%d to nr_cpu_ids=%d.\n", NR_CPUS, nr_cpu_ids); if (IS_ENABLED(CONFIG_RCU_BOOST)) pr_info("\tRCU kthread priority: %d.\n", kthread_prio); + rcupdate_announce_bootup_oddness(); } #ifdef CONFIG_PREEMPT_RCU diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 273e869ca21d..82a5aa10dbc5 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -560,7 +560,8 @@ static DEFINE_RAW_SPINLOCK(rcu_tasks_cbs_lock); DEFINE_SRCU(tasks_rcu_exit_srcu); /* Control stall timeouts. Disable with <= 0, otherwise jiffies till stall. */ -static int rcu_task_stall_timeout __read_mostly = HZ * 60 * 10; +#define RCU_TASK_STALL_TIMEOUT (HZ * 60 * 10) +static int rcu_task_stall_timeout __read_mostly = RCU_TASK_STALL_TIMEOUT; module_param(rcu_task_stall_timeout, int, 0644); static void rcu_spawn_tasks_kthread(void); @@ -851,6 +852,23 @@ static void rcu_spawn_tasks_kthread(void) #endif /* #ifdef CONFIG_TASKS_RCU */ +#ifndef CONFIG_TINY_RCU + +/* + * Print any non-default Tasks RCU settings. + */ +static void __init rcu_tasks_bootup_oddness(void) +{ +#ifdef CONFIG_TASKS_RCU + if (rcu_task_stall_timeout != RCU_TASK_STALL_TIMEOUT) + pr_info("\tTasks-RCU CPU stall warnings timeout set to %d (rcu_task_stall_timeout).\n", rcu_task_stall_timeout); + else + pr_info("\tTasks RCU enabled.\n"); +#endif /* #ifdef CONFIG_TASKS_RCU */ +} + +#endif /* #ifndef CONFIG_TINY_RCU */ + #ifdef CONFIG_PROVE_RCU /* @@ -935,3 +953,25 @@ late_initcall(rcu_verify_early_boot_tests); #else void rcu_early_boot_tests(void) {} #endif /* CONFIG_PROVE_RCU */ + +#ifndef CONFIG_TINY_RCU + +/* + * Print any significant non-default boot-time settings. + */ +void __init rcupdate_announce_bootup_oddness(void) +{ + if (rcu_normal) + pr_info("\tNo expedited grace period (rcu_normal).\n"); + else if (rcu_normal_after_boot) + pr_info("\tNo expedited grace period (rcu_normal_after_boot).\n"); + else if (rcu_expedited) + pr_info("\tAll grace periods are expedited (rcu_expedited).\n"); + if (rcu_cpu_stall_suppress) + pr_info("\tRCU CPU stall warnings suppressed (rcu_cpu_stall_suppress).\n"); + if (rcu_cpu_stall_timeout != CONFIG_RCU_CPU_STALL_TIMEOUT) + pr_info("\tRCU CPU stall warnings timeout set to %d (rcu_cpu_stall_timeout).\n", rcu_cpu_stall_timeout); + rcu_tasks_bootup_oddness(); +} + +#endif /* #ifndef CONFIG_TINY_RCU */ |