Planet Linux Plumbers Conf

(Grand Canyon at Sunset)

After spending a few days manning the Plumbers booth at OSCON, I thought I’d post the answer to the question that everyone seemed to want to know – What is a Linux Plumbers Conference? We came up with the word “Plumbing” to describe the low level infrastructure of a Linux System. This includes the Kernel, desktop infrastructure like X and graphics libraries, system utilities like udev and hal, as well as essential libraries like glibc and friends. These components interface with each other at times – some better than others. We hope to provide a forum for people from these types of projects to get together and try to solve problems that are system wide or cross multiple project boundaries.

In addition to the topics to be discussed in the microconfs and the general talks (see http://linuxplumbersconf.org/program/schedule/), we will have “unconference” style talks. We have several smaller rooms available for people to get together and work out specifics, talk about something they didn’t get on the schedule, or have a group hug. These rooms can be reserved at the start of the conference.

August 18th the registration fee for Plumbers will increase to $300. If you haven’t already registered, what are you waiting for?

This documents my personal flow for downloading and installing a Linux kernel with my xHCI and USB 3.0 code. Until the code is in the upstream kernel and shipping in Linux distributions, you'll have to follow these directions to get Linux USB 3.0 support.

Read more »

In order to implement router style semantics, Vyatta allows setting many different configuration variables and then applying them all at once with a commit command. Currently, this is implemented by a combination of shell magic and unionfs. The problem is that keeping unionfs up to date and fixing the resulting crashes is major pain.

There must be better alternatives, current options include:

• Replace unionfs with aufs which has less users yelling at it and more developers.
• Use a filesystem like btrfs which has snapshots. This changes the model and makes api's like "what changed?" hard to implement.
• Move to a pure userspace model using git. The problem here is that git as currently written is meant for users not transactions.
  
• Use combination of copy, bind mount, and rsync.
• Use a database for configuration. This is easier for general queries but is the most work. Conversion from existing format would be a pain.
  

Looks like a fun/hard problem. Don't expect any resolution soon.

Instead of the old boring "here's what drivers are being merged and deleted" and the like as I've posted in the past, I thought I'd just write about one specific project that has recently gone public that I think is a great indicator of how far the Linux Driver Project has come these days.

From the very beginning, Novell has been extremely supportive of the Linux Driver Project, allowing me to work on it on company time, and has encouraged companies they partner with to participate in it, to get Linux drivers into the main kernel tree. One such company recently has been Ralink.

Two weeks ago I visited Ralink in person for the second time, in Taiwan. The outcome of this meeting, and the previous ones, can be seen this past week on the rt2x00-users mailing list in these four posts, as well as a number of previous posts from Ralink developers.

As you can see in these posts, Ralink is sending patches for the upstream rt2x00 driver for their new chipsets, and not just dumping a huge, stand-alone tarball driver on the community, as they have done in the past. This shows a huge willingness to learn how to deal with the kernel community, and they should be strongly encouraged and praised for this major change in attitude.

I'd like to thank the developers and managers at Ralink for making this very public change, and for commiting the resources to see this through to have full Linux support for their chipsets in the main kernel tree.

By no means is this something that I can claim full, if even partial credit for. There were numerous people at Ralink, Novell, and HP that helped in getting these meetings to happen, and the work done. I'm just happy to be a tiny part of this.

On a personal note, I'd like to thank the Novell Taipei developer team who helped me on my visits, and whom have turned into wonderful kernel developers on their own accord, contributing many upstream patches, as well as becoming the maintainers for a few different drivers in the kernel tree. Without their help, none of this would have been possible.

I just read Charlie Stross's rant on reducing his household's carbon footprint. Summary: He and his wife can live a life of monastic discomfort, wearing moldy scratchy 10-year-old bamboo fiber jumpsuits and shivering in their flat - or, they can cut out one transatlantic flight per year and achieve the equivalent carbon footprint reduction.

I did a similar analysis back around 2007 or so and had the same result: I've got a relatively trim carbon footprint compared to your average first-worlder, except for the air travel that turns it into a bloated planet-eating monster too extreme to fall under the delicate term "footprint." Like Charlie, I am too practical, too technophilic, and too hopeful to accept that the only hope of saving the planet is to regress to third world living standards (fucking eco-ascetics!). I decided that I would only make changes that made my life better, not worse - e.g., living in a walkable urban center (downtown Portland, now SF). But the air travel was a stumper. I liked traveling, and flying around the world for conferences is a vital component of saving the world through open source. Isn't it? Isn't it?

Two things happened that made me re-evaluate my air travel philosophy. One, I started a file systems consulting business and didn't have a lot of spare cash to spend on fripperies. Two, I hurt my back and sitting became massively uncomfortable (still recovering from that one). So I cut down on the flying around the world to Linux conferences involuntarily.

You know what I discovered? I LOVE not flying around the world for Linux conferences. I love taking only a few flights a year. I love flying mostly in the same time zone (yay, West coast). I love having the energy to travel for fun because I'm not all dragged out by the conference circuit. I love hanging out with my friends who live in the same city instead of missing out on all the parties because I'm in fucking Venezuela instead.

Save the planet. Burn your frequent flyer card.

I thought it would be easier to do a round of stable kernel releases in the middle of the larger kernel merge window, to prevent the next round from being so big (given that there are a lot of patches usually applying during the -rc1 merge window cycle).

So, I've now done:

• Linux 2.6.32.54-rc1 release
• Linux 3.0.17-rc1 release
• Linux 3.1.9-rc1 release
• Linux 3.2.1-rc1 release

Please go test and let me know if there are any problems with any of these kernels. If I've missed any patches that you feel should be in them, also please let me know.

Note, this is most likely going to be the LAST 3.1.y kernel release, so please move off to the 3.2 kernel at this point in time. Maintaining so many different kernel branches all at once is not trivial, and I want to minimize it if at all possible.

Woo-hoo!

User-Level Implementations of Read-Copy Update has appeared in the February 2012 issue of IEEE Transactions on Parallel and Distributed Systems. Many thanks to everyone involved, especially co-authors Jon Walpole, Michel R. Dagenais, Alan Stern (who did the symbolic-logic heavy lifting), and Mathieu Desnoyers (who is the lead author). Mathieu also managed to convince me to go once more into the breach, which was not an easy task given that I received my license to collect RCU rejection notices all the way back in 1995. ;-)

So it does feel very good to see this finally hit print!

Thanks to everyone who provided comments, criticisms, and, most of all, patches to the parallel-programming book announced last month. Several of the contributions were quite substantial, particularly a couple that fixed my extensive abuse of the \url{} latex command. A number of the comments had to do with format, and so the new version has a number of improvements:

1. Embedded fonts, which make the PDF compatible with various printing services.
   
2. PDF hyperlinks, both internal and external.
   
3. A set of PDF bookmarks corresponding to the table of contents.
   
4. An experimental single-column version.
   
5. A tarball of an experimental HTML version.
   

A number of people convinced me to move from latex to pdflatex, which I should have done years ago. Quarter-century-old habits die hard, I guess.

I expect to release updates every three to six months. However, for the impatient, git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/perfbook.git will be updated in real time, as always.

Last week I found two tools that make my life better and make me look cool in front of my friends (j/k). So I thought I would share them.

Keeping bookmarks sync'd and accessible Back in the day I used to use a shareware tool to dump my IE bookmarks to html, then upload them via FTP, and then download them again and re-sync. But times have changed and del.icio.us is the new way to bookmark.

For those not in the know del.icio.us is a "social bookmarking" website. The first consequence is that your bookmarks are stored on a globally accessible webserver with an easy to remember URL like http://del.icio.us/philips. The second and more fun aspect is that when you make a bookmark (with one of the great del.icio.us bookmarklets) you can see who else has bookmarked the same page and what other sites may be related and of interest. From this feature I have found some great websites, including my new favorite techno radio station Radio ABF France.

But the coolest part is a plugin for Firefox called Foxlicious that allows you to sync your bookmarks from del.icio.us into a folder, organized by tags. It is great I can bookmark at home, and sync at work, then bookmark at work and sync at home, then; well you get the idea. Zebra Tele-scopic As you may already know I carry with me at most times an analog notebook (you know the paper kind). But I have never been able to find an inexpensive pen that is compact enough to keep in my pocket. Until my faithful run to the store last week where I found it! "It" being the Zebra Tele-scopic pen which is small enough to put in a jean pocket but telescopes into a regular sized and balanced ball point pen. Not only that but they are far cheaper than the Fisher Space Pen. At ~$5.49 US for two tiny telescoping pens with two refills these pens are a great deal!

@Waitinggtoshine http://t.co/HY966hFt

@sofiavillarreal http://t.co/HY966hFt

Hello everyone,

Thanks for making this year’s plumbers conference such an enjoyable event.  Next year, we’re planning to co-locate Plumbers with the Kernel Summit and LinuxCon in San Diego from 29-31 August.  The current plan is that Plumbers and LinuxCon would run as parallel but separate events.  To accommodate the parallelism, we’re still planning on keeping the numbers for Plumbers down to 300 and having a separate registration from LinuxCon.  We’re also planning to move the refereed presentations track into LinuxCon itself as a hard core technical track which would still be selected by the Plumbers Programme committe (both Plumbers and LinuxCon attendees would be able to go to this). We plan to keep the two microconference tracks for plumbers only, but also add a third unconference type track, where people could plan meetings and split into discussion groups in a style very similar to Ubuntu Developer Summit (only Plumbers registered attendees would be able to go to this).

If you have any feedback about this plan, please sent it to the current programme committee at lpc2011@virtuousgeek.org

Of course, we’re also looking to recruit another organising and programme committee for 2013, so if you want to volunteer, please read this web page and then send your bid to the plumbers conference steering committee (who are also the Linux Foundation Technical Advisory Board) at tech-board@lists.linux-foundation.org

For those who want a lift to either San Francisco or its airports, we’ve added a new section to the Ride Sharing wiki.  Please make sure to note which day you need a lift for (Friday or Saturday) and for drivers what time you’ll be leaving.

http://wiki.linuxplumbersconf.org/2011:car_sharing

I’m doing a lot of things this year – and for the hundredth time, I find myself discarding my previous life and blogs and starting anew.

Last October, in a chocolate-induced haze of post Halloween self-satisfaction, I somehow thought it would be a good idea to volunteer to run the Linux Plumbers Conference in 2009. Portland continues to host the event, which makes it possible for me to help out, along with an extraordinarily strong local Linux development and business ecosystem. Last year’s crew did a heck of a job creating the event for the first time. We’re coasting on their toil and troubles, this year, frankly.

Despite the continual incoming dripdripdrip of somber economic news, tightening budgets, market collapses, layoffs, disappearing finances and individual anxieties, we are somehow crafting together what will be a rather interesting and productive conference.

The outstanding news today was we got a lot closer to signing up another big name for our keynote! It won’t get announced anytime soon, unfortunately, but it will be fantastic if we can get them.  We have already lined up Keith Packard, X Window genius and all round great guy to give one of the keynote addresses.

We will also have Linus giving an advanced tutorial on git.  It pains me to impose on Linus, but I’m personally very grateful that James Bottomley did the heroic arm-twisting for us.  After losing the video of Linus’s git tutorial in 2008, we badly wanted a chance to reassemble our dignity and geek cred.

If you’re a Linux developer in Portland, OR (or for that matter, anywhere else), what are you waiting for? Register already!

Linux Plumbers Conference will run from Sept 23-25 in 2009 at the Downtown Portland Marriott.

A useful tool: slock is a tiny c program that locks your screen like xlock. But, with only 147 lines of very straightforward code it would be very difficult to introduce vulnerabilities :)

The Linux networking receive performance has been mostly single threaded until the advent of MSI-X and multiqueue receive hardware. Now with many cards, it is possible to be processing packets on multiple CPU's and cores at once. All this is great, and improves performance for the simple case.

But most users don't just use simple networking. They use useful features like netfilter to do firewalling, NAT, connection tracking and all other forms of wierd and wonderful things. The netfilter code has been tuned over the years, but there are still several hot locks in the receive path. Most of these are reader-writer locks which are actually the worst kind, much worse than a simple spin lock. The problem with locks on modern CPU's is that even for the uncontested case, a lock operation means a full-stop cache miss.

With the help of Eric Duzmet, Rick Jones, Martin Josefsson and others, it looks like there is a solution to most of these. I am excited to see how it all pans out but it could mean a big performance increase for any kind of netfilter packet intensive processing. Stay tuned.

I'm pleased to announce that the eXtensible Host Controller Interface (xHCI) 1.0 specification is now publicly available on intel.com. This is the specification for the PC hardware that talks to all your USB 3.0, USB 2.0, and USB 1.1 devices. (Yes, there are no more companion controllers, xHCI is the one host controller to rule them all).

Open, public documentation is always important to the open source community. Now that the spec is open, anyone can fully understand my Linux xHCI driver (although it's currently only compliant to the 0.96 xHCI spec; anyone want to help fix that?). This also means the BSD developers can implement their own xHCI driver.

Curious what a TRB or a Set TR Deq Ptr command is? Want to know how device contexts or endpoint rings work? Go read the spec!

<p>Since the original <a href="http://www.linuxplumbersconf.org/">Linux Plumbers Conference</a> drew much inspiration from <a href="http://lca2011.linux.org.au/">LCA</a>'s continuing success, it's cool to see some of what Plumbers has done be seen as <a href="http://airlied.livejournal.com/73491.html">worthy of emulating at next year's LCA</a>!</p><p>LCA seems like a great opportunity to specifically try to make progress on cross-project issues. It's quite well-attended so it's likely the people you need in the room to make a decision will be <em>in the room</em>.</p>

<p>I work from home. My basement, actually. I recently read an article in the Times about <a href="http://www.nytimes.com/2010/09/05/science/05robots.html?_r=1&amp;pagewanted=1">increasing the office presence of remote employees with robots</a>. Pretty interesting. How much does one of those robo-Beltzners cost? $5k? This is a neat idea but it's still not released so who knows.<br /><br />I've been thinking about other options for establishing a stronger office presence for myself. Recently I bought a webcam. If I used this to broadcast me, sitting at my desk on Ustream or Livestream, that would certainly make it so my coworkers (and the rest of the world) could see what I was up to, every second of the workday. This is actually a lot <i>more</i> exposure than an office worker, even in a cubicle, would expect. If I'm in an office cube, I might have people stop by, but I'll know they're there, and they won't <i>always</i> be there.&nbsp; There is still generally solitude and privacy to concentrate on the code and be productive. I'm currently trying something that I think is closer to the balance of a real office:<br /><ul><li>Take snapshots from webcam every 15 minutes<br /></li><li>Only during normal working hours</li><li>Give 3 second audible warning before capturing</li><li>Upload to an intranet webserver</li></ul>I haven't found this to be too much of an imposition -- in fact, the quarter-hourly beeps are somewhat like a clock chime.<br /><br />In the beginning, it's hard to resist mugging for the camera, but that passes:<br /><img style="max-width: 800px;" src="http://oss.oracle.com/%7Eagrover/pics/blog/whassup.jpg" alt="whassup???" height="240" width="320" /><br />Think about how this is better than irc or IM, both of which <i>do</i> have activity/presence indicators, but which either aren't used, or poorly implemented and often wrong. How much more likely are you, as a colleague of mine, to IM, email, video chat, or call me if you can see I'm at my desk and working? No more "around?" messages needed. You could even see if I'm looking cheerful, or perhaps otherwise indisposed, heh heh:<br /><img style="max-width: 800px;" src="http://oss.oracle.com/%7Eagrover/pics/blog/cat1.jpg" alt="hello kitty" height="240" width="320" /><br />On a technical note, although there were many Debian packages that kind-of did what I wanted, it turned out to be surprisingly easy to roll my own in about <a href="http://github.com/agrover/pysnapper/blob/master/webcam.py">20 lines of Python</a>.<br /><img style="max-width: 800px;" src="http://oss.oracle.com/%7Eagrover/pics/blog/working.jpg" alt="working hard." height="240" width="320" /><br />Anyways, just something I've been playing around with, while I wait for my robo-avatar to be set up down at HQ...</p>

My LiveJournal blog name - valhenson - was the last major holdover from my old name, Val Henson. I got a new Social Security card, passport, and driver's license with my new name several months ago, but migrating my blog? That's hard! Or something. I finally got around to moving to a brand-spanking-new blog at WordPress:

Valerie Aurora's blog

Update your RSS reader with the above if you still want to read my blog - I won't be republishing my posts to my new blog on this LiveJournal blog.

If you're aware of any other current instances of "Val Henson" or "Valerie Henson," let me know! I obviously can't change my name on historical documents, like research papers or interviews, but if it's vaguely real-time-ish, I'd like to update it.

One web page I'm going to keep as Val Henson for historical reasons is my Val Henson is a Man joke. Several of the pages on my web site were created after the fact as vehicles for amusing pictures or graphics I had lying around. In this case, my friend Dana Sibera created a pretty damn cool picture of me with a full beard and I had to do something with it.



It's doubly wild now that I have such short hair.

Now that you have VMX working, you might notice that kvm/qemu's PS/2 mouse emulation sucks. The VM's mouse cursor totally does not follow the host's mouse cursor at all! That's a horrid mess; how would we clean that up? The ugly hack is to disable PS/2 mouse emulation and present a USB tablet instead:

$ kvm -usb -usbdevice tablet

Now, why is PS/2 mouse emulation messed up in the first place? It turns out that PS/2 mice do not report absolute coordinates; they only tell the OS about relative changes in position. "Two steps up" "Seventeen steps to the right" etc. This is fine with a physical mouse because the physical mouse moves in an arbitrarily defined rectangle that is separate from the screen. The mouse is not placed directly on the screen, so there is no need to know the absolute position of the physical mouse on the screen. In the case of a VM, however, we know the absolute position of the (host) mouse on the screen. Tablets provide a fixed size rectangle with absolute coordinates, and that's why they (should) work better.

Obvious caveat: The VM's graphical windowing system must know about USB and tablets. Allegedly X.org is not good at that, though Windows is.

Update: Recent Ubuntu X.org seems to work....

If you’re ever in the state of Oregon, take the time to visit the  Rice Mineral Museum. I took a trip there today, and it was eye-opening, staggering, and simply wonderful. This is a world-class museum, a Smithsonian-level collection hiding out in the middle of nowhere, also known as the north end of Shute Road in Hillsboro. Their website and photo gallery simply do not do them justice.

Most of the pieces were so staggeringly beautiful that they far outdid commercial art that’s sold for megabucks. Amongst the very cool things, a slice of the collection comes from Pashan, Pune, one of the several places on this planet I call home.

for real.

I couldn’t have been happier with how the Linux Plumbers Conference went last week. I went back and looked at the original proposal that we had Arjan, Greg, and Randy present to the Linux Foundation, and we seem to have hit all our original goals. From conception we wanted this to be a “working” conference – and from the conversations in the hallways that I overheard, to the discussions in the microconfs that went on, I could see that people were indeed getting together, discussing issues and solving problems. Conferences require a lot of time, effort, and money to do right, and it’s gratifying to feel that something useful will come out of this.

I think that now I can go back to blogging about duck poo and vegetables.