refscale: Add locking, both irqsave and otherwise
This commit adds scale_type of lock and lock-irq to test exclusive-locking
acquisition and release. Note that the refscale.nreaders=1 module
parameter is required if you wish to test uncontended locking.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
diff --git a/kernel/rcu/refscale.c b/kernel/rcu/refscale.c
index 02dd976..504c804 100644
--- a/kernel/rcu/refscale.c
+++ b/kernel/rcu/refscale.c
@@ -362,6 +362,75 @@ static struct ref_scale_ops rwsem_ops = {
.name = "rwsem"
};
+// Definitions for spinlock
+static DEFINE_SPINLOCK(test_lock);
+
+static void ref_lock_section(const int nloops)
+{
+ int i;
+
+ preempt_disable();
+ for (i = nloops; i >= 0; i--) {
+ spin_lock(&test_lock);
+ spin_unlock(&test_lock);
+ }
+ preempt_enable();
+}
+
+static void ref_lock_delay_section(const int nloops, const int udl, const int ndl)
+{
+ int i;
+
+ preempt_disable();
+ for (i = nloops; i >= 0; i--) {
+ spin_lock(&test_lock);
+ un_delay(udl, ndl);
+ spin_unlock(&test_lock);
+ }
+ preempt_enable();
+}
+
+static struct ref_scale_ops lock_ops = {
+ .readsection = ref_lock_section,
+ .delaysection = ref_lock_delay_section,
+ .name = "lock"
+};
+
+// Definitions for per-CPU (as in uncontended) irq-save spinlock
+
+static void ref_lock_irq_section(const int nloops)
+{
+ unsigned long flags;
+ int i;
+
+ preempt_disable();
+ for (i = nloops; i >= 0; i--) {
+ spin_lock_irqsave(&test_lock, flags);
+ spin_unlock_irqrestore(&test_lock, flags);
+ }
+ preempt_enable();
+}
+
+static void ref_lock_irq_delay_section(const int nloops, const int udl, const int ndl)
+{
+ unsigned long flags;
+ int i;
+
+ preempt_disable();
+ for (i = nloops; i >= 0; i--) {
+ spin_lock_irqsave(&test_lock, flags);
+ un_delay(udl, ndl);
+ spin_unlock_irqrestore(&test_lock, flags);
+ }
+ preempt_enable();
+}
+
+static struct ref_scale_ops lock_irq_ops = {
+ .readsection = ref_lock_irq_section,
+ .delaysection = ref_lock_irq_delay_section,
+ .name = "lock-irq"
+};
+
static void rcu_scale_one_reader(void)
{
if (readdelay <= 0)
@@ -654,7 +723,7 @@ ref_scale_init(void)
int firsterr = 0;
static struct ref_scale_ops *scale_ops[] = {
&rcu_ops, &srcu_ops, &rcu_trace_ops, &rcu_tasks_ops,
- &refcnt_ops, &rwlock_ops, &rwsem_ops,
+ &refcnt_ops, &rwlock_ops, &rwsem_ops, &lock_ops, &lock_irq_ops,
};
if (!torture_init_begin(scale_type, verbose))
