aboutsummaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
authorLai Jiangshan <laijs@cn.fujitsu.com>2012-03-06 17:57:34 +0800
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>2012-04-30 10:48:24 -0700
commitdc87917501e324701dbfb249def44054b5220187 (patch)
treee39ebf104875f11b8f6fd56e98366918bacc4dca /kernel
parent966f58c2f6df826f385706673a9bb1edcfd3499a (diff)
downloadlinux-dc87917501e324701dbfb249def44054b5220187.tar.gz
rcu: Improve srcu_readers_active_idx()'s cache locality
Expand the calls to srcu_readers_active_idx() from srcu_readers_active() inline. This change improves cache locality by interating over the CPUs once rather than twice. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/srcu.c9
1 files changed, 8 insertions, 1 deletions
diff --git a/kernel/srcu.c b/kernel/srcu.c
index e0139a27485..a43211c9286 100644
--- a/kernel/srcu.c
+++ b/kernel/srcu.c
@@ -193,7 +193,14 @@ static bool srcu_readers_active_idx_check(struct srcu_struct *sp, int idx)
*/
static int srcu_readers_active(struct srcu_struct *sp)
{
- return srcu_readers_active_idx(sp, 0) + srcu_readers_active_idx(sp, 1);
+ int cpu;
+ unsigned long sum = 0;
+
+ for_each_possible_cpu(cpu) {
+ sum += ACCESS_ONCE(per_cpu_ptr(sp->per_cpu_ref, cpu)->c[0]);
+ sum += ACCESS_ONCE(per_cpu_ptr(sp->per_cpu_ref, cpu)->c[1]);
+ }
+ return sum;
}
/**