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

From: K. Y. Srinivasan
Date: Wed Jun 29 2011 - 10:27:24 EST


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@xxxxxxxxxxxxx>
Signed-off-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Signed-off-by: Abhishek Kane <v-abkane@xxxxxxxxxxxxx>
Signed-off-by: Hank Janssen <hjanssen@xxxxxxxxxxxxx>
---
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

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