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Date:   Tue, 25 Jul 2023 14:03:36 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Davidlohr Bueso <dave@stgolabs.net>
Cc:     mingo@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] rcuwait: Add might_sleep() annotations
Message-ID: <20230725120336.GG3765278@hirez.programming.kicks-ass.net>
References: <20230724160337.20851-1-dave@stgolabs.net>
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On Mon, Jul 24, 2023 at 09:03:36AM -0700, Davidlohr Bueso wrote:
> ... as with regular waitqueues.

No immediate objection, but please, tell us more. What made you get up
this fine morning and write this patch?

> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
> ---
>  include/linux/rcuwait.h | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/include/linux/rcuwait.h b/include/linux/rcuwait.h
> index 27343424225c..c0fcac903d03 100644
> --- a/include/linux/rcuwait.h
> +++ b/include/linux/rcuwait.h
> @@ -74,7 +74,10 @@ extern void finish_rcuwait(struct rcuwait *w);
>  })
>  
>  #define rcuwait_wait_event(w, condition, state)				\
> -	___rcuwait_wait_event(w, condition, state, 0, schedule())
> +do {									\
> +	might_sleep();							\
> +	___rcuwait_wait_event(w, condition, state, 0, schedule());	\
> +} while (0)
>  
>  #define __rcuwait_wait_event_timeout(w, condition, state, timeout)	\
>  	___rcuwait_wait_event(w, ___wait_cond_timeout(condition),	\
> @@ -84,6 +87,7 @@ extern void finish_rcuwait(struct rcuwait *w);
>  #define rcuwait_wait_event_timeout(w, condition, state, timeout)	\
>  ({									\
>  	long __ret = timeout;						\
> +	might_sleep();							\
>  	if (!___wait_cond_timeout(condition))				\
>  		__ret = __rcuwait_wait_event_timeout(w, condition,	\
>  						     state, timeout);	\
> -- 
> 2.41.0
>