[PATCH 09/12] include: add kthread wrappers for pollers

[Sascha Hauer]

On Mon, Feb 15, 2021 at 11:37:02AM +0100, Ahmad Fatoum wrote:
> With the new fancy yielding poller support, we can properly represent
> kernel threads in barebox. Do so.
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
> ---
>  include/linux/kthread.h | 72 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 72 insertions(+)
>  create mode 100644 include/linux/kthread.h
> 
> diff --git a/include/linux/kthread.h b/include/linux/kthread.h
> new file mode 100644
> index 000000000000..17b6de9cf168
> --- /dev/null
> +++ b/include/linux/kthread.h
> @@ -0,0 +1,72 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef _LINUX_KTHREAD_H
> +#define _LINUX_KTHREAD_H
> +/* Wrapper around pollers to ease porting from Linux */
> +
> +#include <linux/kernel.h>
> +#include <linux/err.h>
> +#include <linux/string.h>
> +#include <poller.h>
> +
> +struct task_struct {
> +	struct poller_struct poller;
> +	int (*threadfn)(void *data);
> +	void *data;
> +};
> +
> +static inline void kthread_poller(struct poller_struct *poller)
> +{
> +	struct task_struct *task = container_of(poller, struct task_struct, poller);
> +	task->threadfn(task->data);
> +}

kthreads behave differently. When you return from a kthread then the
thread is stopped. We should either behave the same way or use a
different name.

Sascha


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