[PATCH RFC v2 tip/core/rcu 1/2] rcu: Remove cond_resched() from Tiny synchronize_sched()

From	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Newsgroups	linux.kernel
Subject	[PATCH RFC v2 tip/core/rcu 1/2] rcu: Remove cond_resched() from Tiny synchronize_sched()
Date	2017-01-14 09:50 +0100
Message-ID	<sZsca-3Kt-3@gated-at.bofh.it> (permalink)
References	<sZsca-3Kt-5@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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It is now legal to invoke synchronize_sched() at early boot, which causes
Tiny RCU's synchronize_sched() to emit spurious splats.  This commit
therefore removes the cond_resched() from Tiny RCU's synchronize_sched().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
 kernel/rcu/tiny.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
index 1898559e6b60..b23a4d076f3d 100644
--- a/kernel/rcu/tiny.c
+++ b/kernel/rcu/tiny.c
@@ -185,9 +185,6 @@ static __latent_entropy void rcu_process_callbacks(struct softirq_action *unused
  * benefits of doing might_sleep() to reduce latency.)
  *
  * Cool, huh?  (Due to Josh Triplett.)
- *
- * But we want to make this a static inline later.  The cond_resched()
- * currently makes this problematic.
  */
 void synchronize_sched(void)
 {
@@ -195,7 +192,6 @@ void synchronize_sched(void)
 			 lock_is_held(&rcu_lock_map) ||
 			 lock_is_held(&rcu_sched_lock_map),
 			 "Illegal synchronize_sched() in RCU read-side critical section");
-	cond_resched();
 }
 EXPORT_SYMBOL_GPL(synchronize_sched);
 
-- 
2.5.2

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[PATCH RFC v2 tip/core/rcu 1/2] rcu: Remove cond_resched() from Tiny synchronize_sched() "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2017-01-14 09:50 +0100

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