[PATCH 21/40] Staging: hv: netvsc: Leverage the spinlock to manage ref_cnt

K. Y. Srinivasan kys at microsoft.com
Wed Jun 29 14:39:18 UTC 2011


We are using the lock to access the net_device; use this lock to manage the
ref_cnt as well.

Signed-off-by: K. Y. Srinivasan <kys at microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz at microsoft.com>
Signed-off-by: Abhishek Kane <v-abkane at microsoft.com>
Signed-off-by: Hank Janssen <hjanssen at microsoft.com>
---
 drivers/staging/hv/hyperv_net.h |    2 +-
 drivers/staging/hv/netvsc.c     |   16 ++++++++--------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/hv/hyperv_net.h b/drivers/staging/hv/hyperv_net.h
index c6836be..058ca79 100644
--- a/drivers/staging/hv/hyperv_net.h
+++ b/drivers/staging/hv/hyperv_net.h
@@ -369,7 +369,7 @@ struct nvsp_message {
 struct netvsc_device {
 	struct hv_device *dev;
 
-	atomic_t refcnt;
+	int refcnt;
 	atomic_t num_outstanding_sends;
 	bool destroy;
 	bool drain_notify;
diff --git a/drivers/staging/hv/netvsc.c b/drivers/staging/hv/netvsc.c
index f930b9e..9ee264c 100644
--- a/drivers/staging/hv/netvsc.c
+++ b/drivers/staging/hv/netvsc.c
@@ -41,7 +41,7 @@ static struct netvsc_device *alloc_net_device(struct hv_device *device)
 		return NULL;
 
 	/* Set to 2 to allow both inbound and outbound traffic */
-	atomic_set(&net_device->refcnt, 2);
+	net_device->refcnt = 2;
 	net_device->drain_notify = false;
 	net_device->destroy = false;
 	init_waitqueue_head(&net_device->waiting_to_drain);
@@ -60,9 +60,9 @@ static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
 
 	spin_lock_irqsave(&device->ext_lock, flags);
 	net_device = device->ext;
-	if (net_device && (atomic_read(&net_device->refcnt) > 1) &&
+	if (net_device && (net_device->refcnt > 1) &&
 		!net_device->destroy)
-		atomic_inc(&net_device->refcnt);
+		net_device->refcnt++;
 	else
 		net_device = NULL;
 	spin_unlock_irqrestore(&device->ext_lock, flags);
@@ -78,8 +78,8 @@ static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
 
 	spin_lock_irqsave(&device->ext_lock, flags);
 	net_device = device->ext;
-	if (net_device && atomic_read(&net_device->refcnt))
-		atomic_inc(&net_device->refcnt);
+	if (net_device && net_device->refcnt)
+		net_device->refcnt++;
 	else
 		net_device = NULL;
 
@@ -96,7 +96,7 @@ static void put_net_device(struct hv_device *device)
 
 	net_device = device->ext;
 
-	atomic_dec(&net_device->refcnt);
+	net_device->refcnt--;
 	spin_unlock_irqrestore(&device->ext_lock, flags);
 }
 
@@ -389,7 +389,7 @@ int netvsc_device_remove(struct hv_device *device)
 	 * it is safe to dereference the ext pointer.
 	 */
 	net_device = (struct netvsc_device *)device->ext;
-	atomic_dec(&net_device->refcnt);
+	net_device->refcnt--;
 	net_device->destroy = true;
 
 	/*
@@ -400,7 +400,7 @@ int netvsc_device_remove(struct hv_device *device)
 	netvsc_disconnect_vsp(net_device);
 
 	spin_lock_irqsave(&device->ext_lock, flags);
-	atomic_set(&net_device->refcnt, 0);
+	net_device->refcnt = 0;
 	device->ext = NULL;
 	spin_unlock_irqrestore(&device->ext_lock, flags);
 
-- 
1.7.4.1




More information about the devel mailing list