Re: [RFC][PATCH -mm 4/7] Freezer: Introduce freezer-firendly waiting macros

[Pavel Machek <pavel@ucw.cz>]

Hi!

> From: Rafael J. Wysocki <rjw@sisk.pl>
> 
> Introduce freezer-friendly wrappers around wait_event_interruptible() and
> wait_event_interruptible_timeout(), originally defined in <linux/wait.h>, to
> be used in freezable kernel threads.  Make some of the freezable kernel threads
> use them.
> 
> This is necessary for the freezer to stop sending signals to kernel threads,
> which is implemented in the next patch.
> 
> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

ACK, but...

> +/*
> + * Freezer-friendly wrappers around wait_event_interruptible() and
> + * wait_event_interruptible_timeout(), originally defined in <linux/wait.h>
> + */
> +
> +#define wait_event_freezable(wq, condition)				\
> +({									\
> +	int __ret;							\
> +	do {								\
> +		__ret = wait_event_interruptible(wq, 			\
> +				(condition) || freezing(current));	\
> +		try_to_freeze();					\
> +	} while (!(condition));					\
> +	__ret;								\
> +})

...

> Index: linux-2.6.22-rc6-mm1/drivers/media/dvb/dvb-core/dvb_frontend.c
> ===================================================================
> --- linux-2.6.22-rc6-mm1.orig/drivers/media/dvb/dvb-core/dvb_frontend.c	2007-07-11 20:48:04.000000000 +0200
> +++ linux-2.6.22-rc6-mm1/drivers/media/dvb/dvb-core/dvb_frontend.c	2007-07-11 20:51:14.000000000 +0200
> @@ -528,7 +528,8 @@ static int dvb_frontend_thread(void *dat
>  		up(&fepriv->sem);	    /* is locked when we enter the thread... */
>  restart:
>  		timeout = wait_event_interruptible_timeout(fepriv->wait_queue,
> -			dvb_frontend_should_wakeup(fe) || kthread_should_stop(),
> +			dvb_frontend_should_wakeup(fe) || kthread_should_stop()
> +				|| freezing(current),
>  			fepriv->delay);

Should this use the new helper? This change does not seem to match the rest.
 
									Pavel
-- 
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