Commit 7cba4775 authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

rcu: Restructure rcu_check_gp_kthread_starvation() 



This commit removes the rsp and gpa local variables, repurposes the j
local variable and adds a gpk (GP kthread) local to improve readability.

Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
parent f7dd7d44

kernel/rcu/tree.c

+11 −14
Original line number Diff line number Diff line
@@ -1225,24 +1225,21 @@ static const char *gp_state_getname(short gs) 
 */

static void rcu_check_gp_kthread_starvation(void)

{

	unsigned long gpa;

	struct task_struct *gpk = rcu_state.gp_kthread;

	unsigned long j;

	struct rcu_state *rsp = &rcu_state;



	j = jiffies;

	gpa = READ_ONCE(rsp->gp_activity);

	if (j - gpa > 2 * HZ) {

	j = jiffies - READ_ONCE(rcu_state.gp_activity);

	if (j > 2 * HZ) {

		pr_err("%s kthread starved for %ld jiffies! g%ld f%#x %s(%d) ->state=%#lx ->cpu=%d\n",

		       rsp->name, j - gpa,

		       (long)rcu_seq_current(&rsp->gp_seq),

		       rsp->gp_flags,

		       gp_state_getname(rsp->gp_state), rsp->gp_state,

		       rsp->gp_kthread ? rsp->gp_kthread->state : ~0,

		       rsp->gp_kthread ? task_cpu(rsp->gp_kthread) : -1);

		if (rsp->gp_kthread) {

		       rcu_state.name, j,

		       (long)rcu_seq_current(&rcu_state.gp_seq),

		       rcu_state.gp_flags,

		       gp_state_getname(rcu_state.gp_state), rcu_state.gp_state,

		       gpk ? gpk->state : ~0, gpk ? task_cpu(gpk) : -1);

		if (gpk) {

			pr_err("RCU grace-period kthread stack dump:\n");

			sched_show_task(rsp->gp_kthread);

			wake_up_process(rsp->gp_kthread);

			sched_show_task(gpk);

			wake_up_process(gpk);

		}

	}

}