From: Alexandre Belloni <alexandre.belloni@bootlin.com>
To: Kevin Rowland <kevin.p.rowland@gmail.com>
Cc: linux-rtc@vger.kernel.org
Subject: Re: rtc: userspace alarmtimer via posix-timers or timerfd
Date: Fri, 15 Jul 2022 15:35:47 +0200 [thread overview]
Message-ID: <YtFtMzpFQPxnEbHw@mail.local> (raw)
In-Reply-To: <CAHK3GzwVbWBi8OYOmdnDq7nOxwp45qpSFU4UT+wK0=UVUNyQsw@mail.gmail.com>
On 11/07/2022 17:48:49-0700, Kevin Rowland wrote:
> Hello,
>
> I'm curious if there's some mechanism in the kernel to bridge POSIX
> timers (or the timerfd subsystem) and the alarmtimer feature.
> The intent is to give userspace the ability to set timers that
> (optionally) result in the system waking from suspend via RTC alarm.
>
> I was thinking about hacking together something myself in
> `kernel/time/posix-timers.c`, but then found `alarmtimer.c` which, as
> far as I can tell, is exposed only to the rest of the kernel.
>
> Any pointers welcome.
>
alarmtimers are POSIX timers, see https://lwn.net/Articles/429925/
Simply use the CLOCK_REALTIME_ALARM clockid
> Best,
> Kevin
--
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
prev parent reply other threads:[~2022-07-15 13:35 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-12 0:48 rtc: userspace alarmtimer via posix-timers or timerfd Kevin Rowland
2022-07-15 13:35 ` Alexandre Belloni [this message]
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