OSNews: http://www.osnews.com/story/26210/Linux_3_5_released Exploring the Future of Computing en-us Copyright 2001-2013, David Adams adam+nospam@osnews.com Wed, 19 Jun 2013 15:19:00 GMT http://www.osnews.com/images/osnews.gif OSNews.com http://www.osnews.com Wake Locks http://www.osnews.com/thread?527753 http://www.osnews.com/thread?527753 Here's a description of the controversial wake locks being merged from android.

http://lwn.net/images/pdf/suspend_blockers.pdf

My somewhat disconnected opinion is that the overall design seems to be a kludge. but the link apparently mentions google's G1 reference hardware had inadequate power management functionality which must have influenced their design. Sun, 22 Jul 2012 20:20:00 GMT donotreply@osnews.com (Alfman) Comments Comment by orestes http://www.osnews.com/thread?527761 http://www.osnews.com/thread?527761 Looks like some seriously nice performance boosts for the open source radeon drivers Sun, 22 Jul 2012 21:27:00 GMT donotreply@osnews.com (orestes) Comments uprobes http://www.osnews.com/thread?527775 http://www.osnews.com/thread?527775 uprobes look handy for testing application performance. Sun, 22 Jul 2012 23:11:00 GMT donotreply@osnews.com (ideasman42) Comments RE: uprobes http://www.osnews.com/thread?527780 http://www.osnews.com/thread?527780 That's what she said!

(sorry. couldn't help it.) Mon, 23 Jul 2012 01:38:00 GMT donotreply@osnews.com (MechaShiva) Comments RE: Wake Locks http://www.osnews.com/thread?527791 http://www.osnews.com/thread?527791
My somewhat disconnected opinion is that the overall design seems to be a kludge


In other words, a perfect fit for the Linux kernel ;) Mon, 23 Jul 2012 03:52:00 GMT donotreply@osnews.com (Soulbender) Comments Android-style opportunistic suspend http://www.osnews.com/thread?527793 http://www.osnews.com/thread?527793 "Android-style opportunistic suspend"
This looks interesting, anyone care to explain it in layman's terms? Mon, 23 Jul 2012 04:26:00 GMT donotreply@osnews.com (sb56637) Comments RE: Android-style opportunistic suspend http://www.osnews.com/thread?527795 http://www.osnews.com/thread?527795 Tux can now go to bed more often, saving more energy for eventual world domination?

Is that ok?Edited 2012-07-23 04:31 UTC Mon, 23 Jul 2012 04:31:00 GMT donotreply@osnews.com (Elv13) Comments RE[2]: Wake Locks http://www.osnews.com/thread?527796 http://www.osnews.com/thread?527796 Well, we know that there was a lot of pressure to merge google's drivers, which are incompatible without these new wake locks, and I suspect that's the prime reason these are being pushed into mainline.

I dislike that it's a system wide lock, it's a step back from the fine grained sleep states already supported by linux. It also adds a tight coupling between userspace and kernel. Now ordinary user space apps like gmail and google maps on android are responsible for system-wide power management, which seems silly to me.

Whatever the PM problems were with google's reference hardware, they should have fixed the hardware instead of adding these crazy wake locks. Mon, 23 Jul 2012 04:38:00 GMT donotreply@osnews.com (Alfman) Comments RE: Android-style opportunistic suspend http://www.osnews.com/thread?527797 http://www.osnews.com/thread?527797 sb56637,

As I understand it, on a very general level they've added a new synchronisation lock in the kernel, which is accessed directly by userspace applications to block sleep states. Once no userspace applications hold a lock, the entire system immediately enters a sleep state. These transitions occur very frequently as one receives input.


The thing about the google G1 hardware was that it only supported a system-wide sleep state, not per-device, which is why google built that into android. But most hardware can put individual components to sleep and wake them up individually on demand, and I argue is better than a system wide sleep. Someone please correct me if I'm wrong, but I think if any android application is using one device with a wake lock, then all active yet idle devices on the system remain awake during that interval. Mon, 23 Jul 2012 04:59:00 GMT donotreply@osnews.com (Alfman) Comments RE: Wake Locks http://www.osnews.com/thread?527798 http://www.osnews.com/thread?527798 AFAIK the original controversy was that the Linux devs thought Android's suspend mechanism (suspend blockers) was too aggressive and therefore the Linux devs instead created 'autosleep' and 'wake locks' which offers a similar functionality but in a more flexible(?) way and are hoping that the Android devs will use these features instead of suspend blockers, they've also made the API mimic the suspend blocker API so as to make it as easy as possible for the Android devs to pick up. Mon, 23 Jul 2012 05:14:00 GMT donotreply@osnews.com (Valhalla) Comments RE[2]: Wake Locks http://www.osnews.com/thread?527799 http://www.osnews.com/thread?527799 I'd like somebody to explain what the differences are between androids mechanisms and what's been accepted into mainline, if anyone here knows...? Mon, 23 Jul 2012 05:18:00 GMT donotreply@osnews.com (Alfman) Comments RE[3]: Wake Locks http://www.osnews.com/thread?527804 http://www.osnews.com/thread?527804 Perhaps this article sheds some light on it:

https://lwn.net/Articles/479841/

Also, here is technical background on the 'suspend blocker' controversy: (very technical, kernel dev-style)

https://lwn.net/images/pdf/suspend_blockers.pdf

edit: nvm the second one, it's what you linked to in the first postEdited 2012-07-23 06:24 UTC Mon, 23 Jul 2012 06:22:00 GMT donotreply@osnews.com (Valhalla) Comments OT: why sid still on 3.2? http://www.osnews.com/thread?527806 http://www.osnews.com/thread?527806 Anyone knows why debian unstable (which I'm running) is still on 3.2? Mon, 23 Jul 2012 06:45:00 GMT donotreply@osnews.com (r0b0) Comments RE: Wake Locks http://www.osnews.com/thread?527810 http://www.osnews.com/thread?527810 Not exactly. This is what got merged in: https://lwn.net/Articles/479841/.
It's main purpose is to mimic wakelocks using existing kernel machinery in quest for running Android userland on stock Linux kernel and keep changes in drivers minimal. Mon, 23 Jul 2012 07:11:00 GMT donotreply@osnews.com (dsmogor) Comments RE[2]: Wake Locks http://www.osnews.com/thread?527813 http://www.osnews.com/thread?527813 I know it was meant funny, but this case proves otherwise. Wakelock have not yet found its place in the kernel despite huge pressure. Mon, 23 Jul 2012 07:17:00 GMT donotreply@osnews.com (dsmogor) Comments RE: OT: why sid still on 3.2? http://www.osnews.com/thread?527842 http://www.osnews.com/thread?527842 I think because Debian is working on making a release ? They are (almost) in freeze ? Mon, 23 Jul 2012 12:56:00 GMT donotreply@osnews.com (Lennie) Comments RE: OT: why sid still on 3.2? http://www.osnews.com/thread?527873 http://www.osnews.com/thread?527873 If you want a newer kernel added to SID, just add the repos from aptosid-kernel. Then you get new kernels more often. And totally compatible with SID. Mon, 23 Jul 2012 15:06:00 GMT donotreply@osnews.com (judgen) Comments RE[2]: Android-style opportunistic suspend http://www.osnews.com/thread?527912 http://www.osnews.com/thread?527912 Thanks for the explanation! Mon, 23 Jul 2012 19:30:00 GMT donotreply@osnews.com (sb56637) Comments