diff mbox series

[net-next,3/9] s390/qeth: unify the tracking of active cmds on ccw device

Message ID 20210611073341.1634501-4-jwi@linux.ibm.com (mailing list archive)
State Accepted
Commit 3518ae76f2bbc465f7a0d7075fe71815e37b21c6
Delegated to: Netdev Maintainers
Headers show
Series s390/qeth: updates 2021-06-11 | expand

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netdev/tree_selection success Clearly marked for net-next
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netdev/cc_maintainers warning 2 maintainers not CCed: borntraeger@de.ibm.com gor@linux.ibm.com
netdev/source_inline success Was 0 now: 0
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netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/kdoc success Errors and warnings before: 24 this patch: 24
netdev/verify_fixes success Link
netdev/checkpatch warning CHECK: Comparison to NULL could be written "!cmpxchg" WARNING: Using vsprintf specifier '%px' potentially exposes the kernel memory layout, if you don't really need the address please consider using '%p'. WARNING: line length of 86 exceeds 80 columns
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
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Commit Message

Julian Wiedmann June 11, 2021, 7:33 a.m. UTC
We have one field to track _whether_ a cmd is active on a ccw device
('irq_pending'), and one to track _which_ cmd it is ('active_cmd').

Get rid of the irq_pending field, by testing active_cmd for NULL.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
---
 drivers/s390/net/qeth_core.h      | 14 +++++++-------
 drivers/s390/net/qeth_core_main.c | 12 ++++--------
 2 files changed, 11 insertions(+), 15 deletions(-)
diff mbox series

Patch

diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index 4d29801bcf41..ad0e86aa99b2 100644
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -614,7 +614,6 @@  struct qeth_channel {
 	struct ccw_device *ccwdev;
 	struct qeth_cmd_buffer *active_cmd;
 	enum qeth_channel_states state;
-	atomic_t irq_pending;
 };
 
 struct qeth_reply {
@@ -664,11 +663,6 @@  static inline struct ccw1 *__ccw_from_cmd(struct qeth_cmd_buffer *iob)
 	return (struct ccw1 *)(iob->data + ALIGN(iob->length, 8));
 }
 
-static inline bool qeth_trylock_channel(struct qeth_channel *channel)
-{
-	return atomic_cmpxchg(&channel->irq_pending, 0, 1) == 0;
-}
-
 /**
  *  OSA card related definitions
  */
@@ -896,10 +890,16 @@  static inline bool qeth_use_tx_irqs(struct qeth_card *card)
 static inline void qeth_unlock_channel(struct qeth_card *card,
 				       struct qeth_channel *channel)
 {
-	atomic_set(&channel->irq_pending, 0);
+	xchg(&channel->active_cmd, NULL);
 	wake_up(&card->wait_q);
 }
 
+static inline bool qeth_trylock_channel(struct qeth_channel *channel,
+					struct qeth_cmd_buffer *cmd)
+{
+	return cmpxchg(&channel->active_cmd, NULL, cmd) == NULL;
+}
+
 struct qeth_trap_id {
 	__u16 lparnr;
 	char vmname[8];
diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index f22f223a4a6c..83d540f8b527 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -1268,7 +1268,6 @@  static void qeth_irq(struct ccw_device *cdev, unsigned long intparm,
 		iob = (struct qeth_cmd_buffer *) (addr_t)intparm;
 	}
 
-	channel->active_cmd = NULL;
 	qeth_unlock_channel(card, channel);
 
 	rc = qeth_check_irb_error(card, cdev, irb);
@@ -1715,11 +1714,10 @@  static int qeth_stop_channel(struct qeth_channel *channel)
 	rc = ccw_device_set_offline(cdev);
 
 	spin_lock_irq(get_ccwdev_lock(cdev));
-	if (channel->active_cmd) {
+	if (channel->active_cmd)
 		dev_err(&cdev->dev, "Stopped channel while cmd %px was still active\n",
 			channel->active_cmd);
-		channel->active_cmd = NULL;
-	}
+
 	cdev->handler = NULL;
 	spin_unlock_irq(get_ccwdev_lock(cdev));
 
@@ -1732,7 +1730,7 @@  static int qeth_start_channel(struct qeth_channel *channel)
 	int rc;
 
 	channel->state = CH_STATE_DOWN;
-	atomic_set(&channel->irq_pending, 0);
+	xchg(&channel->active_cmd, NULL);
 
 	spin_lock_irq(get_ccwdev_lock(cdev));
 	cdev->handler = qeth_irq;
@@ -2039,7 +2037,7 @@  static int qeth_send_control_data(struct qeth_card *card,
 	reply->param = reply_param;
 
 	timeout = wait_event_interruptible_timeout(card->wait_q,
-						   qeth_trylock_channel(channel),
+						   qeth_trylock_channel(channel, iob),
 						   timeout);
 	if (timeout <= 0) {
 		qeth_put_cmd(iob);
@@ -2059,8 +2057,6 @@  static int qeth_send_control_data(struct qeth_card *card,
 	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));
 	rc = ccw_device_start_timeout(channel->ccwdev, __ccw_from_cmd(iob),
 				      (addr_t) iob, 0, 0, timeout);
-	if (!rc)
-		channel->active_cmd = iob;
 	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));
 	if (rc) {
 		QETH_DBF_MESSAGE(2, "qeth_send_control_data on device %x: ccw_device_start rc = %i\n",