Re: [PATCH 1/6] net: ethernet: ti: netcp: add support of cpts

From: Richard Cochran
Date: Wed Nov 30 2016 - 04:45:04 EST


On Mon, Nov 28, 2016 at 05:04:23PM -0600, Grygorii Strashko wrote:
> @@ -678,6 +744,9 @@ struct gbe_priv {
> int num_et_stats;
> /* Lock for updating the hwstats */
> spinlock_t hw_stats_lock;
> +
> + int cpts_registered;

The usage of this counter is racy.

> + struct cpts *cpts;
> };

This ++ and -- business ...

> +static void gbe_register_cpts(struct gbe_priv *gbe_dev)
> +{
> + if (!gbe_dev->cpts)
> + return;
> +
> + if (gbe_dev->cpts_registered > 0)
> + goto done;
> +
> + if (cpts_register(gbe_dev->cpts)) {
> + dev_err(gbe_dev->dev, "error registering cpts device\n");
> + return;
> + }
> +
> +done:
> + ++gbe_dev->cpts_registered;
> +}
> +
> +static void gbe_unregister_cpts(struct gbe_priv *gbe_dev)
> +{
> + if (!gbe_dev->cpts || (gbe_dev->cpts_registered <= 0))
> + return;
> +
> + if (--gbe_dev->cpts_registered)
> + return;
> +
> + cpts_unregister(gbe_dev->cpts);
> +}

is invoked from your open() and close() methods, but those methods
are not serialized among multiple ports.

Thanks,
Richard