summaryrefslogtreecommitdiffstats
path: root/kernel/rcutree.c
diff options
context:
space:
mode:
authorPaul E. McKenney <paulmck@linux.vnet.ibm.com>2009-08-22 13:56:51 -0700
committerIngo Molnar <mingo@elte.hu>2009-08-23 10:32:39 +0200
commita157229cabd6dd8cfa82525fc9bf730c94cc9ac2 (patch)
tree886013efc2f25dab915640acf46151fac7ae57b4 /kernel/rcutree.c
parent22f00b69f6a7e1e18e821979a23e8307c2de9888 (diff)
downloadblackbird-op-linux-a157229cabd6dd8cfa82525fc9bf730c94cc9ac2.tar.gz
blackbird-op-linux-a157229cabd6dd8cfa82525fc9bf730c94cc9ac2.zip
rcu: Simplify rcu_pending()/rcu_check_callbacks() API
All calls from outside RCU are of the form: if (rcu_pending(cpu)) rcu_check_callbacks(cpu, user); This is silly, instead we put a call to rcu_pending() in rcu_check_callbacks(), and then make the outside calls be to rcu_check_callbacks(). This cuts down on the code a bit and also gives the compiler a better chance of optimizing. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: akpm@linux-foundation.org Cc: mathieu.desnoyers@polymtl.ca Cc: josht@linux.vnet.ibm.com Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org LKML-Reference: <125097461311-git-send-email-> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/rcutree.c')
-rw-r--r--kernel/rcutree.c5
1 files changed, 4 insertions, 1 deletions
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 7c515082ae84..4ce3adcfa94d 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -111,6 +111,7 @@ static int qhimark = 10000; /* If this many pending, ignore blimit. */
static int qlowmark = 100; /* Once only this many pending, use blimit. */
static void force_quiescent_state(struct rcu_state *rsp, int relaxed);
+static int rcu_pending(int cpu);
/*
* Return the number of RCU-sched batches processed thus far for debug & stats.
@@ -974,6 +975,8 @@ static void rcu_do_batch(struct rcu_data *rdp)
*/
void rcu_check_callbacks(int cpu, int user)
{
+ if (!rcu_pending(cpu))
+ return; /* if nothing for RCU to do. */
if (user ||
(idle_cpu(cpu) && rcu_scheduler_active &&
!in_softirq() && hardirq_count() <= (1 << HARDIRQ_SHIFT))) {
@@ -1329,7 +1332,7 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp)
* by the current CPU, returning 1 if so. This function is part of the
* RCU implementation; it is -not- an exported member of the RCU API.
*/
-int rcu_pending(int cpu)
+static int rcu_pending(int cpu)
{
return __rcu_pending(&rcu_sched_state, &per_cpu(rcu_sched_data, cpu)) ||
__rcu_pending(&rcu_bh_state, &per_cpu(rcu_bh_data, cpu));
OpenPOWER on IntegriCloud