Commit ed47155b authored by Julian Wiedmann's avatar Julian Wiedmann Committed by David S. Miller
Browse files

s390/qeth: fine-tune spinlocks 



For quite a lot of code paths it's obvious that they will never run in
IRQ context. So replace their spin_lock_irqsave() calls with
spin_lock_irq().

While at it, get rid of the redundant card pointer in struct qeth_reply
that was used by qeth_send_control_data() to access the card's lock.

Signed-off-by: default avatarJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 31c92732

drivers/s390/net/qeth_core.h

+0 −1
Original line number Diff line number Diff line
@@ -639,7 +639,6 @@ struct qeth_reply { 
	atomic_t received;

	int rc;

	void *param;

	struct qeth_card *card;

	refcount_t refcnt;

};

drivers/s390/net/qeth_core_main.c

+22 −31
Original line number Diff line number Diff line
@@ -592,7 +592,6 @@ static struct qeth_reply *qeth_alloc_reply(struct qeth_card *card) 
	if (reply) {

		refcount_set(&reply->refcnt, 1);

		atomic_set(&reply->received, 0);

		reply->card = card;

	}

	return reply;

}
@@ -1541,15 +1540,14 @@ out: 


static int qeth_clear_channel(struct qeth_channel *channel)

{

	unsigned long flags;

	struct qeth_card *card;

	int rc;



	card = CARD_FROM_CDEV(channel->ccwdev);

	QETH_CARD_TEXT(card, 3, "clearch");

	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);

	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));

	rc = ccw_device_clear(channel->ccwdev, QETH_CLEAR_CHANNEL_PARM);

	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);

	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));



	if (rc)

		return rc;
@@ -1565,15 +1563,14 @@ static int qeth_clear_channel(struct qeth_channel *channel) 


static int qeth_halt_channel(struct qeth_channel *channel)

{

	unsigned long flags;

	struct qeth_card *card;

	int rc;



	card = CARD_FROM_CDEV(channel->ccwdev);

	QETH_CARD_TEXT(card, 3, "haltch");

	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);

	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));

	rc = ccw_device_halt(channel->ccwdev, QETH_HALT_CHANNEL_PARM);

	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);

	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));



	if (rc)

		return rc;
@@ -1667,7 +1664,6 @@ static int qeth_read_conf_data(struct qeth_card *card, void **buffer, 
	char *rcd_buf;

	int ret;

	struct qeth_channel *channel = &card->data;

	unsigned long flags;



	/*

	 * scan for RCD command in extended SenseID data
@@ -1681,11 +1677,11 @@ static int qeth_read_conf_data(struct qeth_card *card, void **buffer, 


	qeth_setup_ccw(channel->ccw, ciw->cmd, ciw->count, rcd_buf);

	channel->state = CH_STATE_RCD;

	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);

	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));

	ret = ccw_device_start_timeout(channel->ccwdev, channel->ccw,

				       QETH_RCD_PARM, LPM_ANYPATH, 0,

				       QETH_RCD_TIMEOUT);

	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);

	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));

	if (!ret)

		wait_event(card->wait_q,

			   (channel->state == CH_STATE_RCD_DONE ||
@@ -1843,7 +1839,6 @@ static int qeth_idx_activate_get_answer(struct qeth_channel *channel, 
			struct qeth_cmd_buffer *))

{

	struct qeth_cmd_buffer *iob;

	unsigned long flags;

	int rc;

	struct qeth_card *card;
@@ -1858,10 +1853,10 @@ static int qeth_idx_activate_get_answer(struct qeth_channel *channel, 
	wait_event(card->wait_q,

		   atomic_cmpxchg(&channel->irq_pending, 0, 1) == 0);

	QETH_DBF_TEXT(SETUP, 6, "noirqpnd");

	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);

	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));

	rc = ccw_device_start_timeout(channel->ccwdev, channel->ccw,

				      (addr_t) iob, 0, 0, QETH_TIMEOUT);

	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);

	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));



	if (rc) {

		QETH_DBF_MESSAGE(2, "Error2 in activating channel rc=%d\n", rc);
@@ -1888,7 +1883,6 @@ static int qeth_idx_activate_channel(struct qeth_channel *channel, 
{

	struct qeth_card *card;

	struct qeth_cmd_buffer *iob;

	unsigned long flags;

	__u16 temp;

	__u8 tmp;

	int rc;
@@ -1928,10 +1922,10 @@ static int qeth_idx_activate_channel(struct qeth_channel *channel, 
	wait_event(card->wait_q,

		   atomic_cmpxchg(&channel->irq_pending, 0, 1) == 0);

	QETH_DBF_TEXT(SETUP, 6, "noirqpnd");

	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);

	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));

	rc = ccw_device_start_timeout(channel->ccwdev, channel->ccw,

				      (addr_t) iob, 0, 0, QETH_TIMEOUT);

	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);

	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));



	if (rc) {

		QETH_DBF_MESSAGE(2, "Error1 in activating channel. rc=%d\n",
@@ -2112,7 +2106,6 @@ int qeth_send_control_data(struct qeth_card *card, int len, 
{

	struct qeth_channel *channel = iob->channel;

	int rc;

	unsigned long flags;

	struct qeth_reply *reply = NULL;

	unsigned long timeout, event_timeout;

	struct qeth_ipa_cmd *cmd = NULL;
@@ -2145,26 +2138,26 @@ int qeth_send_control_data(struct qeth_card *card, int len, 
	}

	qeth_prepare_control_data(card, len, iob);



	spin_lock_irqsave(&card->lock, flags);

	spin_lock_irq(&card->lock);

	list_add_tail(&reply->list, &card->cmd_waiter_list);

	spin_unlock_irqrestore(&card->lock, flags);

	spin_unlock_irq(&card->lock);



	timeout = jiffies + event_timeout;



	QETH_CARD_TEXT(card, 6, "noirqpnd");

	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);

	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));

	rc = ccw_device_start_timeout(channel->ccwdev, channel->ccw,

				      (addr_t) iob, 0, 0, event_timeout);

	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);

	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));

	if (rc) {

		QETH_DBF_MESSAGE(2, "%s qeth_send_control_data: "

			"ccw_device_start rc = %i\n",

			dev_name(&channel->ccwdev->dev), rc);

		QETH_CARD_TEXT_(card, 2, " err%d", rc);

		spin_lock_irqsave(&card->lock, flags);

		spin_lock_irq(&card->lock);

		list_del_init(&reply->list);

		qeth_put_reply(reply);

		spin_unlock_irqrestore(&card->lock, flags);

		spin_unlock_irq(&card->lock);

		qeth_release_buffer(channel, iob);

		atomic_set(&channel->irq_pending, 0);

		wake_up(&card->wait_q);
@@ -2192,9 +2185,9 @@ int qeth_send_control_data(struct qeth_card *card, int len, 


time_err:

	reply->rc = -ETIME;

	spin_lock_irqsave(&reply->card->lock, flags);

	spin_lock_irq(&card->lock);

	list_del_init(&reply->list);

	spin_unlock_irqrestore(&reply->card->lock, flags);

	spin_unlock_irq(&card->lock);

	atomic_inc(&reply->received);

	rc = reply->rc;

	qeth_put_reply(reply);
@@ -5776,7 +5769,6 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev) 
	struct device *dev;

	int rc;

	enum qeth_discipline_id enforced_disc;

	unsigned long flags;

	char dbf_name[DBF_NAME_LEN];



	QETH_DBF_TEXT(SETUP, 2, "probedev");
@@ -5834,9 +5826,9 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev) 
		break;

	}



	write_lock_irqsave(&qeth_core_card_list.rwlock, flags);

	write_lock_irq(&qeth_core_card_list.rwlock);

	list_add_tail(&card->list, &qeth_core_card_list.list);

	write_unlock_irqrestore(&qeth_core_card_list.rwlock, flags);

	write_unlock_irq(&qeth_core_card_list.rwlock);

	return 0;



err_disc:
@@ -5852,7 +5844,6 @@ err_dev: 


static void qeth_core_remove_device(struct ccwgroup_device *gdev)

{

	unsigned long flags;

	struct qeth_card *card = dev_get_drvdata(&gdev->dev);



	QETH_DBF_TEXT(SETUP, 2, "removedv");
@@ -5862,9 +5853,9 @@ static void qeth_core_remove_device(struct ccwgroup_device *gdev) 
		qeth_core_free_discipline(card);

	}



	write_lock_irqsave(&qeth_core_card_list.rwlock, flags);

	write_lock_irq(&qeth_core_card_list.rwlock);

	list_del(&card->list);

	write_unlock_irqrestore(&qeth_core_card_list.rwlock, flags);

	write_unlock_irq(&qeth_core_card_list.rwlock);

	free_netdev(card->dev);

	qeth_core_free_card(card);

	dev_set_drvdata(&gdev->dev, NULL);

drivers/s390/net/qeth_l2_main.c

+2 −3
Original line number Diff line number Diff line
@@ -1209,7 +1209,6 @@ static int qeth_osn_send_control_data(struct qeth_card *card, int len, 
			   struct qeth_cmd_buffer *iob)

{

	struct qeth_channel *channel = iob->channel;

	unsigned long flags;

	int rc = 0;



	QETH_CARD_TEXT(card, 5, "osndctrd");
@@ -1218,10 +1217,10 @@ static int qeth_osn_send_control_data(struct qeth_card *card, int len, 
		   atomic_cmpxchg(&channel->irq_pending, 0, 1) == 0);

	qeth_prepare_control_data(card, len, iob);

	QETH_CARD_TEXT(card, 6, "osnoirqp");

	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);

	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));

	rc = ccw_device_start_timeout(channel->ccwdev, channel->ccw,

				      (addr_t) iob, 0, 0, QETH_IPA_TIMEOUT);

	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);

	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));

	if (rc) {

		QETH_DBF_MESSAGE(2, "qeth_osn_send_control_data: "

			   "ccw_device_start rc = %i\n", rc);

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