[PATCH] RCU: introduce rcu_needs_cpu() interface

With "Paul E. McKenney" <paulmck@us.ibm.com>

Introduce rcu_needs_cpu() interface.  This can be used to tell if there
will be a new rcu batch on a cpu soon by looking at the curlist pointer.
This can be used to avoid to enter a tickless idle state where the cpu
would miss that a new batch is ready when rcu_start_batch would be called
on a different cpu.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Heiko Carstens 2006-05-15 09:43:58 -07:00 committed by Linus Torvalds
parent 3b7c810827
commit 986733e01d
2 changed files with 20 additions and 0 deletions

View file

@ -132,6 +132,7 @@ static inline void rcu_bh_qsctr_inc(int cpu)
}
extern int rcu_pending(int cpu);
extern int rcu_needs_cpu(int cpu);
/**
* rcu_read_lock - mark the beginning of an RCU read-side critical section.