[PATCH tip/core/rcu 34/88] rcu: Update rcu_bootup_announce_oddness()

From: Paul E. McKenney
Date: Thu May 25 2017 - 18:05:17 EST


This commit updates rcu_bootup_announce_oddness() to check additional
Kconfig options and module/boot parameters.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/tree.c | 9 ++++++---
kernel/rcu/tree_plugin.h | 31 ++++++++++++++++++++++++++++---
2 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index b01a02e7a0b7..ac8dce15fd74 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -536,9 +536,12 @@ void rcu_all_qs(void)
}
EXPORT_SYMBOL_GPL(rcu_all_qs);

-static long blimit = 10; /* Maximum callbacks per rcu_do_batch. */
-static long qhimark = 10000; /* If this many pending, ignore blimit. */
-static long qlowmark = 100; /* Once only this many pending, use blimit. */
+#define DEFAULT_RCU_BLIMIT 10 /* Maximum callbacks per rcu_do_batch. */
+static long blimit = DEFAULT_RCU_BLIMIT;
+#define DEFAULT_RCU_QHIMARK 10000 /* If this many pending, ignore blimit. */
+static long qhimark = DEFAULT_RCU_QHIMARK;
+#define DEFAULT_RCU_QLOMARK 100 /* Once only this many pending, use blimit. */
+static long qlowmark = DEFAULT_RCU_QLOMARK;

module_param(blimit, long, 0444);
module_param(qhimark, long, 0444);
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index eb5ebdce25ff..9cb3dff78b6f 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -79,7 +79,9 @@ static void __init rcu_bootup_announce_oddness(void)
pr_info("\tHierarchical RCU autobalancing is disabled.\n");
if (IS_ENABLED(CONFIG_RCU_FAST_NO_HZ))
pr_info("\tRCU dyntick-idle grace-period acceleration is enabled.\n");
- if (IS_ENABLED(CONFIG_PROVE_RCU))
+ if (IS_ENABLED(CONFIG_PROVE_RCU_REPEATEDLY))
+ pr_info("\tRCU lockdep checking is permanently enabled.\n");
+ else if (IS_ENABLED(CONFIG_PROVE_RCU))
pr_info("\tRCU lockdep checking is enabled.\n");
if (RCU_NUM_LVLS >= 4)
pr_info("\tFour(or more)-level hierarchy is enabled.\n");
@@ -90,8 +92,31 @@ static void __init rcu_bootup_announce_oddness(void)
pr_info("\tBoot-time adjustment of leaf fanout to %d.\n", rcu_fanout_leaf);
if (nr_cpu_ids != NR_CPUS)
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);
+#ifdef CONFIG_RCU_BOOST
+ pr_info("\tRCU priority boosting: priority %d delay %d ms.\n", kthread_prio, CONFIG_RCU_BOOST_DELAY);
+#endif
+ if (blimit != DEFAULT_RCU_BLIMIT)
+ pr_info("\tBoot-time adjustment of callback invocation limit to %ld.\n", blimit);
+ if (qhimark != DEFAULT_RCU_QHIMARK)
+ pr_info("\tBoot-time adjustment of callback high-water mark to %ld.\n", qhimark);
+ if (qlowmark != DEFAULT_RCU_QLOMARK)
+ pr_info("\tBoot-time adjustment of callback low-water mark to %ld.\n", qlowmark);
+ if (jiffies_till_first_fqs != ULONG_MAX)
+ pr_info("\tBoot-time adjustment of first FQS scan delay to %ld jiffies.\n", jiffies_till_first_fqs);
+ if (jiffies_till_next_fqs != ULONG_MAX)
+ pr_info("\tBoot-time adjustment of subsequent FQS scan delay to %ld jiffies.\n", jiffies_till_next_fqs);
+ if (rcu_kick_kthreads)
+ pr_info("\tKick kthreads if too-long grace period.\n");
+ if (IS_ENABLED(CONFIG_DEBUG_OBJECTS_RCU_HEAD))
+ pr_info("\tRCU callback double-/use-after-free debug enabled.\n");
+ if (IS_ENABLED(CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT))
+ pr_info("\tRCU debug GP pre-init slowdown %d jiffies.\n", gp_preinit_delay);
+ if (IS_ENABLED(CONFIG_RCU_TORTURE_TEST_SLOW_INIT))
+ pr_info("\tRCU debug GP init slowdown %d jiffies.\n", gp_init_delay);
+ if (IS_ENABLED(CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP))
+ pr_info("\tRCU debug GP init slowdown %d jiffies.\n", gp_cleanup_delay);
+ if (IS_ENABLED(CONFIG_RCU_EQS_DEBUG))
+ pr_info("\tRCU debug extended QS entry/exit.\n");
rcupdate_announce_bootup_oddness();
}

--
2.5.2