Re: [PATCH] niu: Use refcount_t for refcount

From: Chuhong Yuan
Date: Fri Aug 02 2019 - 12:16:20 EST


Chuhong Yuan <hslester96@xxxxxxxxx> ä2019å8æ2æåä äå8:57åéï
>
> refcount_t is better for reference counters since its
> implementation can prevent overflows.
> So convert atomic_t ref counters to refcount_t.
>
> Also convert refcount from 0-based to 1-based.

It seems that directly converting refcount from 0-based to
1-based is infeasible.
I am sorry for this mistake.

Regards,
Chuhong

>
> Signed-off-by: Chuhong Yuan <hslester96@xxxxxxxxx>
> ---
> drivers/net/ethernet/sun/niu.c | 6 +++---
> drivers/net/ethernet/sun/niu.h | 2 +-
> 2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/ethernet/sun/niu.c b/drivers/net/ethernet/sun/niu.c
> index 0bc5863bffeb..5bf096e51db7 100644
> --- a/drivers/net/ethernet/sun/niu.c
> +++ b/drivers/net/ethernet/sun/niu.c
> @@ -9464,7 +9464,7 @@ static struct niu_parent *niu_new_parent(struct niu *np,
> memcpy(&p->id, id, sizeof(*id));
> p->plat_type = ptype;
> INIT_LIST_HEAD(&p->list);
> - atomic_set(&p->refcnt, 0);
> + refcount_set(&p->refcnt, 1);
> list_add(&p->list, &niu_parent_list);
> spin_lock_init(&p->lock);
>
> @@ -9524,7 +9524,7 @@ static struct niu_parent *niu_get_parent(struct niu *np,
> port_name);
> if (!err) {
> p->ports[port] = np;
> - atomic_inc(&p->refcnt);
> + refcount_inc(&p->refcnt);
> }
> }
> mutex_unlock(&niu_parent_lock);
> @@ -9552,7 +9552,7 @@ static void niu_put_parent(struct niu *np)
> p->ports[port] = NULL;
> np->parent = NULL;
>
> - if (atomic_dec_and_test(&p->refcnt)) {
> + if (refcount_dec_and_test(&p->refcnt)) {
> list_del(&p->list);
> platform_device_unregister(p->plat_dev);
> }
> diff --git a/drivers/net/ethernet/sun/niu.h b/drivers/net/ethernet/sun/niu.h
> index 04c215f91fc0..755e6dd4c903 100644
> --- a/drivers/net/ethernet/sun/niu.h
> +++ b/drivers/net/ethernet/sun/niu.h
> @@ -3071,7 +3071,7 @@ struct niu_parent {
>
> struct niu *ports[NIU_MAX_PORTS];
>
> - atomic_t refcnt;
> + refcount_t refcnt;
> struct list_head list;
>
> spinlock_t lock;
> --
> 2.20.1
>