From 0c8e0e3c37955d17cced37222a10c00ab47efd4b Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 28 Apr 2017 11:24:22 -0700 Subject: [PATCH] srcu: Print non-default exp_holdoff values at boot time This commit makes srcu_bootup_announce() check for non-default values of the auto-expedite holdoff time exp_holdoff and print a message if so. Signed-off-by: Paul E. McKenney --- kernel/rcu/srcutree.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c index 08d43736f72a..0b6ea105d9f8 100644 --- a/kernel/rcu/srcutree.c +++ b/kernel/rcu/srcutree.c @@ -40,7 +40,9 @@ #include "rcu.h" #include "rcu_segcblist.h" -static ulong exp_holdoff = 25 * 1000; /* Holdoff (ns) for auto-expediting. */ +/* Holdoff in nanoseconds for auto-expediting. */ +#define DEFAULT_SRCU_EXP_HOLDOFF (25 * 1000) +static ulong exp_holdoff = DEFAULT_SRCU_EXP_HOLDOFF; module_param(exp_holdoff, ulong, 0444); static void srcu_invoke_callbacks(struct work_struct *work); @@ -1171,6 +1173,8 @@ EXPORT_SYMBOL_GPL(srcutorture_get_gp_data); static int __init srcu_bootup_announce(void) { pr_info("Hierarchical SRCU implementation.\n"); + if (exp_holdoff != DEFAULT_SRCU_EXP_HOLDOFF) + pr_info("\tNon-default auto-expedite holdoff of %lu ns.\n", exp_holdoff); return 0; } early_initcall(srcu_bootup_announce);