Re: [PATCH] scheduler: wait: Added missing include freezer.h

Ingo Molnar
2018-10-29T06:02:01Z

* Carmeli Tamir <carmeli.tamir@gmail.com> wrote:

> The function 'wait_event_freezable' calls '__wait_event_freezable' that
> uses 'try_to_freeze', which is defined in freezer.h.
> This causes a compilation error for callers of 'wait_event_freezables',
> forcing them to include also freezer.h.
>
> Signed-off-by: Carmeli Tamir <carmeli.tamir@gmail.com>
> ---
> include/linux/wait.h | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/include/linux/wait.h b/include/linux/wait.h
> index ed7c122..75061ee 100644
> --- a/include/linux/wait.h
> +++ b/include/linux/wait.h
> @@ -4,6 +4,7 @@
> /*
> * Linux wait queue related types and methods
> */
> +#include <linux/freezer.h>
> #include <linux/list.h>
> #include <linux/stddef.h>
> #include <linux/spinlock.h>

I don't think we should do this, because freezer.h then includes
<linux/sched.h> - while much of the point of <linux/wait.h> was to not
include the huge chain of dependencies that sched.h invokes...

BTW., another way this could be solved is to uninline try_to_freeze(), it
seems a bit large at first sight to be inlined - but I could be wrong.

Once it's not inline we could just add this to wait.h:

extern bool try_to_freeze(void);

or so. This decouples wait.h from freezer.h.

Thanks,

Ingo