2023-07-24 17:17:23

by Davidlohr Bueso

Subject: [PATCH] rcuwait: Add might_sleep() annotations

... as with regular waitqueues.

Signed-off-by: Davidlohr Bueso <[email protected]>
---
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

2023-07-25 12:51:32

by Peter Zijlstra

Subject: Re: [PATCH] rcuwait: Add might_sleep() annotations

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 <[email protected]>
> ---
> 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
>

2023-07-25 15:21:48

by Davidlohr Bueso

Subject: Re: [PATCH] rcuwait: Add might_sleep() annotations

On Tue, 25 Jul 2023, Peter Zijlstra wrote:

>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?

So this was just something I had noticed missing while adding the
timeout support.

Thanks,
Davidlohr