From fd4b352687fd8604d49c190c4c9ea9e369fd42d5 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Sat, 5 May 2012 19:10:35 -0700 Subject: rcu: Update RCU_FAST_NO_HZ tracing for lazy callbacks In the current code, a short dyntick-idle interval (where there is at least one non-lazy callback on the CPU) and a long dyntick-idle interval (where there are only lazy callbacks on the CPU) are traced identically, which can be less than helpful. This commit therefore emits different event traces in these two cases. Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney Tested-by: Heiko Carstens Tested-by: Pascal Chapperon --- kernel/rcutree_plugin.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 2411000d986..5449f02c482 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -2165,15 +2165,17 @@ static void rcu_prepare_for_idle(int cpu) !rcu_pending(cpu) && !local_softirq_pending()) { /* Can we go dyntick-idle despite still having callbacks? */ - trace_rcu_prep_idle("Dyntick with callbacks"); per_cpu(rcu_dyntick_drain, cpu) = 0; per_cpu(rcu_dyntick_holdoff, cpu) = jiffies; - if (rcu_cpu_has_nonlazy_callbacks(cpu)) + if (rcu_cpu_has_nonlazy_callbacks(cpu)) { + trace_rcu_prep_idle("Dyntick with callbacks"); per_cpu(rcu_idle_gp_timer_expires, cpu) = jiffies + RCU_IDLE_GP_DELAY; - else + } else { per_cpu(rcu_idle_gp_timer_expires, cpu) = jiffies + RCU_IDLE_LAZY_GP_DELAY; + trace_rcu_prep_idle("Dyntick with lazy callbacks"); + } tp = &per_cpu(rcu_idle_gp_timer, cpu); mod_timer_pinned(tp, per_cpu(rcu_idle_gp_timer_expires, cpu)); per_cpu(rcu_nonlazy_posted_snap, cpu) = -- cgit v1.2.3