rcu: Add forward-progress diagnostic for per-CPU kthreads

Increment a per-CPU counter on each pass through rcu_cpu_kthread()'s
service loop, and add it to the rcudata trace output.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit is contained in:
Paul E. McKenney
2011-04-22 18:08:51 -07:00
committed by Paul E. McKenney
parent 15ba0ba860
commit 5ece5bab3e
3 changed files with 27 additions and 18 deletions

View File

@@ -93,6 +93,7 @@ EXPORT_SYMBOL_GPL(rcu_scheduler_active);
static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task);
DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
DEFINE_PER_CPU(int, rcu_cpu_kthread_cpu);
DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
static DEFINE_PER_CPU(wait_queue_head_t, rcu_cpu_wq);
DEFINE_PER_CPU(char, rcu_cpu_has_work);
static char rcu_kthreads_spawnable;
@@ -1625,6 +1626,7 @@ static int rcu_cpu_kthread(void *arg)
break;
}
*statusp = RCU_KTHREAD_RUNNING;
per_cpu(rcu_cpu_kthread_loops, cpu)++;
local_irq_save(flags);
work = *workp;
*workp = 0;