[PATCH 095/117] Staging: hv: netvsc: Leverage the spinlock to manage refcnt

[K. Y. Srinivasan]

Now that we have a spin lock protecting the device pointer, use it to also
protect the refrence count.

Signed-off-by: K. Y. Srinivasan <k...@microsoft.com>
Signed-off-by: Haiyang Zhang <haiya...@microsoft.com>
---
 drivers/staging/hv/hyperv_net.h |    2 +-
 drivers/staging/hv/netvsc.c     |   18 +++++++++---------
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/hv/hyperv_net.h b/drivers/staging/hv/hyperv_net.h
index 0b347c1..5c8fc31 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;
        /*
diff --git a/drivers/staging/hv/netvsc.c b/drivers/staging/hv/netvsc.c
index 0411332..3b234a3 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->destroy = false;
        net_device->dev = device;
@@ -58,9 +58,9 @@ 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);
@@ -76,8 +76,8 @@ 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;
 
@@ -94,7 +94,7 @@ 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);
 }
 
@@ -385,7 +385,7 @@ int netvsc_device_remove(struct hv_device *device)
                spin_unlock_irqrestore(&device->ext_lock, flags);
                return -ENODEV;
        }
-       atomic_dec(&net_device->refcnt);
+       net_device->refcnt--;
        net_device->destroy = true;
        spin_unlock_irqrestore(&device->ext_lock, flags);
 
@@ -401,7 +401,7 @@ int netvsc_device_remove(struct hv_device *device)
        netvsc_disconnect_vsp(net_device);
 
        spin_lock_irqsave(&device->ext_lock, flags);
-       atomic_dec(&net_device->refcnt);
+       net_device->refcnt--;
        device->ext = NULL;
        spin_unlock_irqrestore(&device->ext_lock, flags);
 
@@ -414,7 +414,7 @@ int netvsc_device_remove(struct hv_device *device)
         * Since the send path is non-blocking, it is reasonable to busy
         * wait here.
         */
-       while (atomic_read(&net_device->refcnt))
+       while (net_device->refcnt != 0)
                udelay(100);
 
        /* At this point, no one should be accessing netDevice except in here */
-- 
1.7.4.1

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