Commit 94c43bda authored by Julian Wiedmann's avatar Julian Wiedmann Committed by Vasily Gorbik
Browse files

s390/qdio: simplify thinint device registration 



On an interrupt, tiqdio_thinint_handler() walks a list of all objects
that might require attention, and checks their DSCI. This list is
awkwardly built from Input Queues, even though the IRQs are per-device
and the queue is then only used to dereference its qdio_irq parent.

To simplify the logic, change the code so that tiq_list contains
qdio_irq entries.

Signed-off-by: default avatarJulian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: default avatarBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent 46112810

drivers/s390/cio/qdio.h

+3 −5
Original line number Diff line number Diff line
@@ -252,9 +252,6 @@ struct qdio_q { 
	/* input or output queue */

	int is_input_q;



	/* list of thinint input queues */

	struct list_head entry;



	/* upper-layer program handler */

	qdio_handler_t (*handler);
@@ -272,6 +269,7 @@ struct qdio_irq { 
	struct qib qib;

	u32 *dsci;		/* address of device state change indicator */

	struct ccw_device *cdev;

	struct list_head entry;		/* list of thinint devices */

	struct dentry *debugfs_dev;

	struct dentry *debugfs_perf;
@@ -373,8 +371,8 @@ extern u64 last_ai_time; 
void qdio_setup_thinint(struct qdio_irq *irq_ptr);

int qdio_establish_thinint(struct qdio_irq *irq_ptr);

void qdio_shutdown_thinint(struct qdio_irq *irq_ptr);

void tiqdio_add_input_queues(struct qdio_irq *irq_ptr);

void tiqdio_remove_input_queues(struct qdio_irq *irq_ptr);

void tiqdio_add_device(struct qdio_irq *irq_ptr);

void tiqdio_remove_device(struct qdio_irq *irq_ptr);

void tiqdio_inbound_processing(unsigned long q);

int tiqdio_allocate_memory(void);

void tiqdio_free_memory(void);

drivers/s390/cio/qdio_main.c

+3 −2
Original line number Diff line number Diff line
@@ -1162,7 +1162,7 @@ int qdio_shutdown(struct ccw_device *cdev, int how) 
	 */

	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);



	tiqdio_remove_input_queues(irq_ptr);

	tiqdio_remove_device(irq_ptr);

	qdio_shutdown_queues(cdev);

	qdio_shutdown_debug_entries(irq_ptr);
@@ -1284,6 +1284,7 @@ int qdio_allocate(struct qdio_initialize *init_data) 
			     init_data->no_output_qs))

		goto out_rel;



	INIT_LIST_HEAD(&irq_ptr->entry);

	init_data->cdev->private->qdio_data = irq_ptr;

	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);

	return 0;
@@ -1428,7 +1429,7 @@ int qdio_activate(struct ccw_device *cdev) 
	}



	if (is_thinint_irq(irq_ptr))

		tiqdio_add_input_queues(irq_ptr);

		tiqdio_add_device(irq_ptr);



	/* wait for subchannel to become active */

	msleep(5);

drivers/s390/cio/qdio_setup.c

+0 −2
Original line number Diff line number Diff line
@@ -150,7 +150,6 @@ static int __qdio_allocate_qs(struct qdio_q **irq_ptr_qs, int nr_queues) 
			return -ENOMEM;

		}

		irq_ptr_qs[i] = q;

		INIT_LIST_HEAD(&q->entry);

	}

	return 0;

}
@@ -179,7 +178,6 @@ static void setup_queues_misc(struct qdio_q *q, struct qdio_irq *irq_ptr, 
	q->mask = 1 << (31 - i);

	q->nr = i;

	q->handler = handler;

	INIT_LIST_HEAD(&q->entry);

}



static void setup_storage_lists(struct qdio_q *q, struct qdio_irq *irq_ptr,

drivers/s390/cio/qdio_thinint.c

+7 −17
Original line number Diff line number Diff line
@@ -66,26 +66,20 @@ static void put_indicator(u32 *addr) 
	atomic_dec(&ind->count);

}



void tiqdio_add_input_queues(struct qdio_irq *irq_ptr)

void tiqdio_add_device(struct qdio_irq *irq_ptr)

{

	mutex_lock(&tiq_list_lock);

	list_add_rcu(&irq_ptr->input_qs[0]->entry, &tiq_list);

	list_add_rcu(&irq_ptr->entry, &tiq_list);

	mutex_unlock(&tiq_list_lock);

}



void tiqdio_remove_input_queues(struct qdio_irq *irq_ptr)

void tiqdio_remove_device(struct qdio_irq *irq_ptr)

{

	struct qdio_q *q;



	q = irq_ptr->input_qs[0];

	if (!q)

		return;



	mutex_lock(&tiq_list_lock);

	list_del_rcu(&q->entry);

	list_del_rcu(&irq_ptr->entry);

	mutex_unlock(&tiq_list_lock);

	synchronize_rcu();

	INIT_LIST_HEAD(&q->entry);

	INIT_LIST_HEAD(&irq_ptr->entry);

}



static inline int has_multiple_inq_on_dsci(struct qdio_irq *irq_ptr)
@@ -174,7 +168,7 @@ static inline void tiqdio_call_inq_handlers(struct qdio_irq *irq) 
static void tiqdio_thinint_handler(struct airq_struct *airq, bool floating)

{

	u32 si_used = clear_shared_ind();

	struct qdio_q *q;

	struct qdio_irq *irq;



	last_ai_time = S390_lowcore.int_clock;

	inc_irq_stat(IRQIO_QAI);
@@ -182,12 +176,8 @@ static void tiqdio_thinint_handler(struct airq_struct *airq, bool floating) 
	/* protect tiq_list entries, only changed in activate or shutdown */

	rcu_read_lock();



	/* check for work on all inbound thinint queues */

	list_for_each_entry_rcu(q, &tiq_list, entry) {

		struct qdio_irq *irq;



	list_for_each_entry_rcu(irq, &tiq_list, entry) {

		/* only process queues from changed sets */

		irq = q->irq_ptr;

		if (unlikely(references_shared_dsci(irq))) {

			if (!si_used)

				continue;

CRA Git | Maintained and supported by SUSTech CRA and CCSE