Re: [PATCH 07/12] drivers/media: Employ atomic_fetch_inc()

From: Mauro Carvalho Chehab
Date: Wed Jul 13 2016 - 12:12:32 EST


Em Mon, 20 Jun 2016 13:05:59 -0700
Davidlohr Bueso <dave@xxxxxxxxxxxx> escreveu:

> Now that we have fetch_inc() we can stop using inc_return() - 1.
>
> These are very similar to the existing OP-RETURN primitives we already
> have, except they return the value of the atomic variable _before_
> modification.
>
> Cc: Hans Verkuil <hans.verkuil@xxxxxxxxx>
> Cc: Andy Walls <awalls@xxxxxxxxxxxxxxxx>
> Cc: linux-media@xxxxxxxxxxxxxxx
> Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>

I suspect that you'll be applying this together with the other patches
in this series. So:

Acked-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>

> ---
> drivers/media/pci/cobalt/cobalt-driver.c | 2 +-
> drivers/media/pci/cx18/cx18-driver.c | 2 +-
> drivers/media/v4l2-core/v4l2-device.c | 2 +-
> 3 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/media/pci/cobalt/cobalt-driver.c b/drivers/media/pci/cobalt/cobalt-driver.c
> index 8d6f04fc8013..70dfcb0c6a72 100644
> --- a/drivers/media/pci/cobalt/cobalt-driver.c
> +++ b/drivers/media/pci/cobalt/cobalt-driver.c
> @@ -683,7 +683,7 @@ static int cobalt_probe(struct pci_dev *pci_dev,
> int i;
>
> /* FIXME - module parameter arrays constrain max instances */
> - i = atomic_inc_return(&cobalt_instance) - 1;
> + i = atomic_fetch_inc(&cobalt_instance);
>
> cobalt = kzalloc(sizeof(struct cobalt), GFP_ATOMIC);
> if (cobalt == NULL)
> diff --git a/drivers/media/pci/cx18/cx18-driver.c b/drivers/media/pci/cx18/cx18-driver.c
> index 260e462d91b4..5cb3408c6859 100644
> --- a/drivers/media/pci/cx18/cx18-driver.c
> +++ b/drivers/media/pci/cx18/cx18-driver.c
> @@ -908,7 +908,7 @@ static int cx18_probe(struct pci_dev *pci_dev,
> struct cx18 *cx;
>
> /* FIXME - module parameter arrays constrain max instances */
> - i = atomic_inc_return(&cx18_instance) - 1;
> + i = atomic_fetch_inc(&cx18_instance);
> if (i >= CX18_MAX_CARDS) {
> printk(KERN_ERR "cx18: cannot manage card %d, driver has a "
> "limit of 0 - %d\n", i, CX18_MAX_CARDS - 1);
> diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c
> index 06fa5f1b2cff..1bc5b68c2724 100644
> --- a/drivers/media/v4l2-core/v4l2-device.c
> +++ b/drivers/media/v4l2-core/v4l2-device.c
> @@ -76,7 +76,7 @@ EXPORT_SYMBOL_GPL(v4l2_device_put);
> int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
> atomic_t *instance)
> {
> - int num = atomic_inc_return(instance) - 1;
> + int num = atomic_fetch_inc(instance);
> int len = strlen(basename);
>
> if (basename[len - 1] >= '0' && basename[len - 1] <= '9')



Thanks,
Mauro