Commit e9b800db authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

refscale: Add acqrel, lock, and lock-irq 



This commit adds scale_type of acqrel, lock, and lock-irq to
test acquisition and release.  Note that the refscale.nreaders=1
module parameter is required if you wish to test uncontended locking.
In contrast, acqrel uses a per-CPU variable, so should be just fine with
large values of the refscale.nreaders=1 module parameter.

Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent 0092eae4

kernel/rcu/refscale.c

+107 −2
Original line number Diff line number Diff line
@@ -362,6 +362,111 @@ static struct ref_scale_ops rwsem_ops = { 
	.name		= "rwsem"

};



// Definitions for global 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 global 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"

};



// Definitions acquire-release.

static DEFINE_PER_CPU(unsigned long, test_acqrel);



static void ref_acqrel_section(const int nloops)

{

	unsigned long x;

	int i;



	preempt_disable();

	for (i = nloops; i >= 0; i--) {

		x = smp_load_acquire(this_cpu_ptr(&test_acqrel));

		smp_store_release(this_cpu_ptr(&test_acqrel), x + 1);

	}

	preempt_enable();

}



static void ref_acqrel_delay_section(const int nloops, const int udl, const int ndl)

{

	unsigned long x;

	int i;



	preempt_disable();

	for (i = nloops; i >= 0; i--) {

		x = smp_load_acquire(this_cpu_ptr(&test_acqrel));

		un_delay(udl, ndl);

		smp_store_release(this_cpu_ptr(&test_acqrel), x + 1);

	}

	preempt_enable();

}



static struct ref_scale_ops acqrel_ops = {

	.readsection	= ref_acqrel_section,

	.delaysection	= ref_acqrel_delay_section,

	.name		= "acqrel"

};



static void rcu_scale_one_reader(void)

{

	if (readdelay <= 0)
@@ -653,8 +758,8 @@ ref_scale_init(void) 
	long i;

	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,

		&rcu_ops, &srcu_ops, &rcu_trace_ops, &rcu_tasks_ops, &refcnt_ops, &rwlock_ops,

		&rwsem_ops, &lock_ops, &lock_irq_ops, &acqrel_ops,

	};



	if (!torture_init_begin(scale_type, verbose))