Messages in this thread |  | | | From | "Rafael J. Wysocki" <> | | Subject | Re: [suspend/resume] Re: userspace notification from module | | Date | Mon, 4 Jan 2010 20:45:44 +0100 |
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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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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