[PATCH tip/core/rcu 07/20] rcu: Remove short-term CPU kicking

Paul E. McKenney
2017-01-14T09:13:36Z

Commit 4914950aaa12d ("rcu: Stop treating in-kernel CPU-bound workloads
as errors") added a (relatively) short-timeout call to resched_cpu().
This was inspired by as issue that was fixed by b7e7ade34e61 ("sched/core:
Fix remote wakeups"). But given that this issue was fixed, it is time
for the current commit to remove this call to resched_cpu().

Reported-by: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
kernel/rcu/tree.c | 6 ------
1 file changed, 6 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 83bf054e194e..3c0d6c129718 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -1220,12 +1220,6 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp,
rdp->rsp->jiffies_resched += 5; /* Re-enable beating. */
}

- /* And if it has been a really long time, kick the CPU as well. */
- if (ULONG_CMP_GE(jiffies,
- rdp->rsp->gp_start + 2 * jiffies_till_sched_qs) ||
- ULONG_CMP_GE(jiffies, rdp->rsp->gp_start + jiffies_till_sched_qs))
- resched_cpu(rdp->cpu); /* Force CPU into scheduler. */
-
return 0;
}

--
2.5.2