Alan Stern <[email protected]> writes:
> On Fri, 20 Jul 2007 [email protected] wrote:
>> > Userspace can submit I/O requests. Someone will have to audit every
>> > driver to make sure that such I/O requests don't cause a quiesced
>> > device to become active. If the device is active, it will make the
>> > memory snapshot inconsistent with the on-device data.
>>
>> assuming this is the suspend-from-ram after a kexec back from the
>> write-to-disk kernel I don't think you are correct.
>>
>> when doing a suspend-to-ram you get to a point where you just don't use
>> any userspace.
> What do you mean? How can you prevent user tasks from running? That's
> basically what the freezer does, and the whole point of this approach
> is to eliminate the freezer. Right?
Presumably no tasks at all would be scheduled.
>> from that point on you are just walking the device tree
>> putting things into low-power mode. This is the point where we are talking
>> about jumping to.
> Yes. And putting things into low-power mode requires the ability to
> run the scheduler, which means that user tasks can be scheduled, which
> means that they can run.
Does it really (fundamentally) require scheduling tasks, particularly in
the case that the devices have already been put in the "quiesced" state?
--
Jeremy Maitin-Shepard
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
