From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Daniel Borkmann <danborkmann@googlemail.com>
Cc: "Bartłomiej Zimoń" <uzi18@o2.pl>,
linux-kernel@vger.kernel.org, awalls@radix.net,
linux-pm@lists.linux-foundation.org, stern@rowland.harvard.edu
Subject: Re: [suspend/resume] Re: userspace notification from module
Date: Mon, 4 Jan 2010 20:45:44 +0100 [thread overview]
Message-ID: <201001042045.44372.rjw@sisk.pl> (raw)
In-Reply-To: <4B41E318.4050809@gmail.com>
On Monday 04 January 2010, Daniel Borkmann wrote:
> Rafael J. Wysocki wrote:
> > On Monday 04 January 2010, Bartłomiej Zimoń wrote:
> >> And what do You think about sending extra signals to processes?
> >
> > I don't see a problem with this in principle, although I don't think signals
> > are very suitable for this particular purpose, because you need two-way
> > communication between the power manager and the processes it's going to
> > notify (because it has to wait for the processes to finish their preparations
> > and to tell it that they are ready).
>
> Again, just to abandon some thoughts... do you really need that "two-way
> communication"? I mean if the kernel delivers that specific signal to
> the process/task_struct [do_signal():handle_signal()] it has to save the
> original execution context that will later on be restored after the
> non-default signal handling function returns. This is our ACK /
> notification for the successful return of the programs "suspend
> handler". The kernel module (if such exists) could be notified about
> that for instance by a simple notifier hook within kernelspace. I mean
> if I see this right, the "two-way" is just for the ACK isn't it?
_If_ the kernel sends the signals, which is not I think should be done.
Please keep that in the user space. Really.
I don't see _any_ good reason for putting such things into the kernel.
Rafael
next prev parent reply other threads:[~2010-01-04 19:45 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-02 13:29 userspace notification from module Bartłomiej Zimoń
2010-01-02 14:04 ` Daniel Borkmann
2010-01-02 14:27 ` [suspend/resume] " Bartłomiej Zimoń
2010-01-02 15:11 ` Oliver Neukum
[not found] ` <6f52f5b81001020713j5435cfadr1143806a9026adc2@mail.gmail.com>
2010-01-02 15:15 ` Daniel Borkmann
2010-01-02 15:40 ` Andy Walls
2010-01-02 15:56 ` Daniel Borkmann
2010-01-02 18:26 ` Bartłomiej Zimoń
2010-01-02 21:01 ` Rafael J. Wysocki
[not found] ` <7cf4f51f.5fc2a5cd.4b3fc3ad.c849c@o2.pl>
2010-01-02 23:29 ` Rafael J. Wysocki
2010-01-03 17:20 ` Bartłomiej Zimoń
2010-01-03 21:50 ` Rafael J. Wysocki
[not found] ` <65e5aef6.33251eb4.4b3fecf4.a2f99@o2.pl>
2010-01-03 9:30 ` Daniel Borkmann
2010-01-03 10:06 ` Daniel Borkmann
[not found] ` <43bd3f9d.71702a8b.4b407900.b542@o2.pl>
2010-01-03 21:49 ` Rafael J. Wysocki
2010-01-04 13:38 ` Stefan Seyfried
2010-01-03 21:33 ` Rafael J. Wysocki
2010-01-03 21:29 ` Rafael J. Wysocki
[not found] ` <24fb84fa.38887c91.4b411ffd.e7f1f@o2.pl>
2010-01-03 23:30 ` Rafael J. Wysocki
2010-01-03 23:35 ` Bartłomiej Zimoń
2010-01-03 23:45 ` Rafael J. Wysocki
2010-01-04 0:51 ` Bartłomiej Zimoń
2010-01-04 1:06 ` Bartłomiej Zimoń
2010-01-04 19:43 ` Rafael J. Wysocki
2010-01-05 9:07 ` [linux-pm] " Anders Eriksson
[not found] ` <7e89c5d.77f82021.4b43a8d7.127e1@o2.pl>
2010-01-05 21:23 ` Rafael J. Wysocki
2010-01-05 22:12 ` Bartłomiej Zimoń
2010-01-05 23:03 ` Rafael J. Wysocki
[not found] ` <1ab86ec9.7bc73105.4b43cd45.c2747@o2.pl>
2010-01-06 14:35 ` Anders Eriksson
2010-01-06 20:37 ` [linux-pm] [suspend/resume] Re: userspace notific ation " Bartłomiej Zimoń
2010-01-06 20:49 ` Roland Dreier
2010-01-06 20:56 ` Roland Dreier
2010-01-15 20:02 ` [linux-pm] [suspend/resume] Re: userspace notification " Pavel Machek
2010-01-05 21:26 ` Stefan Seyfried
[not found] ` <11f818a7.4b53f68a.4b43bb9b.b3a7f@o2.pl>
2010-01-05 23:05 ` Rafael J. Wysocki
2010-01-04 12:46 ` Daniel Borkmann
2010-01-04 19:45 ` Rafael J. Wysocki [this message]
2010-01-09 10:32 ` Pavel Machek
2010-01-09 13:40 ` Rafael J. Wysocki
2010-01-15 20:03 ` Pavel Machek
2010-01-15 22:14 ` Rafael J. Wysocki
2010-01-16 3:00 ` Eric Miao
2010-01-16 17:00 ` Stanislav Brabec
2010-01-16 18:12 ` Pavel Machek
2010-01-16 22:05 ` Rafael J. Wysocki
2010-01-16 22:19 ` Pavel Machek
2010-01-16 22:25 ` Pavel Machek
2010-01-16 22:31 ` Rafael J. Wysocki
2010-01-16 22:26 ` Rafael J. Wysocki
2010-01-17 13:07 ` Pavel Machek
2010-01-17 13:26 ` Russell King - ARM Linux
2010-01-19 5:15 ` Pavel Machek
2010-01-16 22:32 ` Russell King - ARM Linux
2010-01-16 18:12 ` Pavel Machek
2010-01-16 18:12 ` Pavel Machek
2010-01-16 22:07 ` Rafael J. Wysocki
2010-01-16 22:14 ` Pavel Machek
2010-01-16 22:21 ` Rafael J. Wysocki
2010-01-02 21:20 ` Bartłomiej Zimoń
2010-01-02 14:31 ` Bartłomiej Zimoń
2010-01-02 22:34 Bartłomiej Zimoń
2010-01-03 8:31 Bartłomiej Zimoń
2010-01-03 11:06 Bartłomiej Zimoń
2010-01-03 23:17 Bartłomiej Zimoń
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