refcount_t is better for reference counters since its
implementation can prevent overflows.
So convert atomic_t ref counters to refcount_t.
Signed-off-by: Chuhong Yuan <[email protected]>
---
drivers/net/ethernet/broadcom/cnic.c | 26 ++++++++++++-------------
drivers/net/ethernet/broadcom/cnic_if.h | 6 +++---
2 files changed, 16 insertions(+), 16 deletions(-)
diff --git a/drivers/net/ethernet/broadcom/cnic.c b/drivers/net/ethernet/broadcom/cnic.c
index 57dc3cbff36e..215777d63cda 100644
--- a/drivers/net/ethernet/broadcom/cnic.c
+++ b/drivers/net/ethernet/broadcom/cnic.c
@@ -141,22 +141,22 @@ static int cnic_uio_close(struct uio_info *uinfo, struct inode *inode)
static inline void cnic_hold(struct cnic_dev *dev)
{
- atomic_inc(&dev->ref_count);
+ refcount_inc(&dev->ref_count);
}
static inline void cnic_put(struct cnic_dev *dev)
{
- atomic_dec(&dev->ref_count);
+ refcount_dec(&dev->ref_count);
}
static inline void csk_hold(struct cnic_sock *csk)
{
- atomic_inc(&csk->ref_count);
+ refcount_inc(&csk->ref_count);
}
static inline void csk_put(struct cnic_sock *csk)
{
- atomic_dec(&csk->ref_count);
+ refcount_dec(&csk->ref_count);
}
static struct cnic_dev *cnic_from_netdev(struct net_device *netdev)
@@ -177,12 +177,12 @@ static struct cnic_dev *cnic_from_netdev(struct net_device *netdev)
static inline void ulp_get(struct cnic_ulp_ops *ulp_ops)
{
- atomic_inc(&ulp_ops->ref_count);
+ refcount_inc(&ulp_ops->ref_count);
}
static inline void ulp_put(struct cnic_ulp_ops *ulp_ops)
{
- atomic_dec(&ulp_ops->ref_count);
+ refcount_dec(&ulp_ops->ref_count);
}
static void cnic_ctx_wr(struct cnic_dev *dev, u32 cid_addr, u32 off, u32 val)
@@ -494,7 +494,7 @@ int cnic_register_driver(int ulp_type, struct cnic_ulp_ops *ulp_ops)
}
read_unlock(&cnic_dev_lock);
- atomic_set(&ulp_ops->ref_count, 0);
+ refcount_set(&ulp_ops->ref_count, 0);
rcu_assign_pointer(cnic_ulp_tbl[ulp_type], ulp_ops);
mutex_unlock(&cnic_lock);
@@ -545,12 +545,12 @@ int cnic_unregister_driver(int ulp_type)
mutex_unlock(&cnic_lock);
synchronize_rcu();
- while ((atomic_read(&ulp_ops->ref_count) != 0) && (i < 20)) {
+ while ((refcount_read(&ulp_ops->ref_count) != 0) && (i < 20)) {
msleep(100);
i++;
}
- if (atomic_read(&ulp_ops->ref_count) != 0)
+ if (refcount_read(&ulp_ops->ref_count) != 0)
pr_warn("%s: Failed waiting for ref count to go to zero\n",
__func__);
return 0;
@@ -3596,7 +3596,7 @@ static int cnic_cm_create(struct cnic_dev *dev, int ulp_type, u32 cid,
}
csk1 = &cp->csk_tbl[l5_cid];
- if (atomic_read(&csk1->ref_count))
+ if (refcount_read(&csk1->ref_count))
return -EAGAIN;
if (test_and_set_bit(SK_F_INUSE, &csk1->flags))
@@ -3651,7 +3651,7 @@ static int cnic_cm_destroy(struct cnic_sock *csk)
csk_hold(csk);
clear_bit(SK_F_INUSE, &csk->flags);
smp_mb__after_atomic();
- while (atomic_read(&csk->ref_count) != 1)
+ while (refcount_read(&csk->ref_count) != 1)
msleep(1);
cnic_cm_cleanup(csk);
@@ -5432,11 +5432,11 @@ static void cnic_free_dev(struct cnic_dev *dev)
{
int i = 0;
- while ((atomic_read(&dev->ref_count) != 0) && i < 10) {
+ while ((refcount_read(&dev->ref_count) != 0) && i < 10) {
msleep(100);
i++;
}
- if (atomic_read(&dev->ref_count) != 0)
+ if (refcount_read(&dev->ref_count) != 0)
netdev_err(dev->netdev, "Failed waiting for ref count to go to zero\n");
netdev_info(dev->netdev, "Removed CNIC device\n");
diff --git a/drivers/net/ethernet/broadcom/cnic_if.h b/drivers/net/ethernet/broadcom/cnic_if.h
index 789e5c7e9311..5232a05ac7ba 100644
--- a/drivers/net/ethernet/broadcom/cnic_if.h
+++ b/drivers/net/ethernet/broadcom/cnic_if.h
@@ -300,7 +300,7 @@ struct cnic_sock {
#define SK_F_CLOSING 7
#define SK_F_HW_ERR 8
- atomic_t ref_count;
+ refcount_t ref_count;
u32 state;
struct kwqe kwqe1;
struct kwqe kwqe2;
@@ -335,7 +335,7 @@ struct cnic_dev {
#define CNIC_F_CNIC_UP 1
#define CNIC_F_BNX2_CLASS 3
#define CNIC_F_BNX2X_CLASS 4
- atomic_t ref_count;
+ refcount_t ref_count;
u8 mac_addr[ETH_ALEN];
int max_iscsi_conn;
@@ -378,7 +378,7 @@ struct cnic_ulp_ops {
char *data, u16 data_size);
int (*cnic_get_stats)(void *ulp_ctx);
struct module *owner;
- atomic_t ref_count;
+ refcount_t ref_count;
};
int cnic_register_driver(int ulp_type, struct cnic_ulp_ops *ulp_ops);
--
2.20.1
On Wed, Jul 31, 2019 at 5:22 AM Chuhong Yuan <[email protected]> wrote:
> static void cnic_ctx_wr(struct cnic_dev *dev, u32 cid_addr, u32 off, u32 val)
> @@ -494,7 +494,7 @@ int cnic_register_driver(int ulp_type, struct cnic_ulp_ops *ulp_ops)
> }
> read_unlock(&cnic_dev_lock);
>
> - atomic_set(&ulp_ops->ref_count, 0);
> + refcount_set(&ulp_ops->ref_count, 0);
> rcu_assign_pointer(cnic_ulp_tbl[ulp_type], ulp_ops);
> mutex_unlock(&cnic_lock);
>
Willem's comment applies here too. The driver needs to be modified to
count from 1 to use refcount_t.
Thanks.
Michael Chan <[email protected]> 于2019年8月1日周四 上午1:58写道：
>
> On Wed, Jul 31, 2019 at 5:22 AM Chuhong Yuan <[email protected]> wrote:
>
> > static void cnic_ctx_wr(struct cnic_dev *dev, u32 cid_addr, u32 off, u32 val)
> > @@ -494,7 +494,7 @@ int cnic_register_driver(int ulp_type, struct cnic_ulp_ops *ulp_ops)
> > }
> > read_unlock(&cnic_dev_lock);
> >
> > - atomic_set(&ulp_ops->ref_count, 0);
> > + refcount_set(&ulp_ops->ref_count, 0);
> > rcu_assign_pointer(cnic_ulp_tbl[ulp_type], ulp_ops);
> > mutex_unlock(&cnic_lock);
> >
>
> Willem's comment applies here too. The driver needs to be modified to
> count from 1 to use refcount_t.
>
> Thanks.
I have revised this problem but find the other two refcounts -
cnic_dev::ref_count
and cnic_sock::ref_count have no set.
I am not sure where to initialize them to 1.
Besides, should ulp_ops->ref_count be set to 0 when unregistered?
On Wed, Jul 31, 2019 at 7:22 PM Chuhong Yuan <[email protected]> wrote:
>
> Michael Chan <[email protected]> 于2019年8月1日周四 上午1:58写道：
> >
> > On Wed, Jul 31, 2019 at 5:22 AM Chuhong Yuan <[email protected]> wrote:
> >
> > > static void cnic_ctx_wr(struct cnic_dev *dev, u32 cid_addr, u32 off, u32 val)
> > > @@ -494,7 +494,7 @@ int cnic_register_driver(int ulp_type, struct cnic_ulp_ops *ulp_ops)
> > > }
> > > read_unlock(&cnic_dev_lock);
> > >
> > > - atomic_set(&ulp_ops->ref_count, 0);
> > > + refcount_set(&ulp_ops->ref_count, 0);
> > > rcu_assign_pointer(cnic_ulp_tbl[ulp_type], ulp_ops);
> > > mutex_unlock(&cnic_lock);
> > >
> >
> > Willem's comment applies here too. The driver needs to be modified to
> > count from 1 to use refcount_t.
> >
> > Thanks.
>
> I have revised this problem but find the other two refcounts -
> cnic_dev::ref_count
> and cnic_sock::ref_count have no set.
> I am not sure where to initialize them to 1.
>
> Besides, should ulp_ops->ref_count be set to 0 when unregistered?
I will send a patch to fix up the initialization of all the atomic ref
counts. After that, you can add your patch to convert to refcount_t.