[PATCH] alarmtimer: return correct remaining time

[PATCH] alarmtimer: return correct remaining time

[Andrei Vagin]

To calculate a remaining time, we need to subtract the current time from
the expiration time. Currently, arguments of ktime_sub are swapped.

Signed-off-by: Andrei Vagin <avagin@gmail.com>
---
 kernel/time/alarmtimer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 2c97e8c2d29f..0519a8805aab 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -594,7 +594,7 @@ static ktime_t alarm_timer_remaining(struct k_itimer *timr, ktime_t now)
 {
 	struct alarm *alarm = &timr->it.alarm.alarmtimer;
 
-	return ktime_sub(now, alarm->node.expires);
+	return ktime_sub(alarm->node.expires, now);
 }
 
 /**
-- 
2.20.1

Re: [PATCH] alarmtimer: return correct remaining time

[Mukesh Ojha]

On 4/8/2019 9:45 AM, Andrei Vagin wrote:
> To calculate a remaining time, we need to subtract the current time from
> the expiration time. Currently, arguments of ktime_sub are swapped.
>
> Signed-off-by: Andrei Vagin <avagin@gmail.com>
> ---
>   kernel/time/alarmtimer.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
> index 2c97e8c2d29f..0519a8805aab 100644
> --- a/kernel/time/alarmtimer.c
> +++ b/kernel/time/alarmtimer.c
> @@ -594,7 +594,7 @@ static ktime_t alarm_timer_remaining(struct k_itimer *timr, ktime_t now)
>   {
>   	struct alarm *alarm = &timr->it.alarm.alarmtimer;
>   
> -	return ktime_sub(now, alarm->node.expires);
> +	return ktime_sub(alarm->node.expires, now);


Looks good to me.
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>

Cheers,
-Mukesh

>   }
>   
>   /**

[tip:timers/urgent] alarmtimer: Return correct remaining time

[tip-bot for Andrei Vagin]

Commit-ID:  07d7e12091f4ab869cc6a4bb276399057e73b0b3
Gitweb:     https://git.kernel.org/tip/07d7e12091f4ab869cc6a4bb276399057e73b0b3
Author:     Andrei Vagin <avagin@gmail.com>
AuthorDate: Sun, 7 Apr 2019 21:15:42 -0700
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Wed, 10 Apr 2019 15:23:26 +0200

alarmtimer: Return correct remaining time

To calculate a remaining time, it's required to subtract the current time
from the expiration time. In alarm_timer_remaining() the arguments of
ktime_sub are swapped.

Fixes: d653d8457c76 ("alarmtimer: Implement remaining callback")
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190408041542.26338-1-avagin@gmail.com

---
 kernel/time/alarmtimer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 2c97e8c2d29f..0519a8805aab 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -594,7 +594,7 @@ static ktime_t alarm_timer_remaining(struct k_itimer *timr, ktime_t now)
 {
 	struct alarm *alarm = &timr->it.alarm.alarmtimer;
 
-	return ktime_sub(now, alarm->node.expires);
+	return ktime_sub(alarm->node.expires, now);
 }
 
 /**