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Robert Love, Preemptible Kernel Maintainer Interviewed

Posted by michael on from the better-than-a-dayplanner dept.

Tom F writes: "LinuxDevices did an interesting interview with Robert Love, the maintainer of the Linux preemptible kernel along with MontaVista. It is an exciting read and has Robert's usual wit and insight."

3 of 183 comments (clear)

  1. True geek by gorillasoft · · Score: 5, Funny

    Like all true geeks, Love doesn't forget to include in his comments that, despite being a computer nerd, he does, in fact, have a girlfriend.

    RL: Approximately how much time per week do you spend working on your kernel patch for Linux?

    Love: My girlfriend would probably say too much. Anywhere from a couple hours a week to many hours a day.

  2. Resumable Pre-emtable OS calls by leighklotz · · Score: 4, Funny
    The ITS operating system (the world's second timesharing system, and the system for which RMS and others first developed EMACS) had a concept of state checkpoints in OS calls, called PCLSRing.

    Alan Bawden wrote a paper on it, and it's quite a good read. His web site has a compressed .gz version, but I found an HTML version of the HTML PCLSR Paper and I quote from its abstract here:

    Under any timesharing operating system there will be occasions when a process must access the state of another process. A process may need to start, stop, debug, load, dump, create, or destroy another process. There is also one occasion when a process must access its own state: an interrupt handler needs access to the state of the running process prior to the arrival of the interrupt, so that the process may continue after the interrupt has been dealt with.

    "PCLSRing" is a mechanism the ITS operating system uses to enforce a kind of modularity when a process must access the state of another process. The modularity principle is very simple: no process ever catches another process (including itself) in the act of executing a system call. System calls thus behave as if they were directly implemented in hardware. A process can no more catch another process in the middle of deleting a file than it can catch another process in the middle of a multiply instruction.

    There was also a way to put the system into a PCLSR test mode that exercised all these control points within the system calls, to help debug them. See SYSDOC TEST documentation extracted from the now decomissioned AI PDP-10 that originally served it up as ftp://ftp.ai.mit.edu/pub/alan/its/sysdoc.tgz (yes, ITS was on the Arpanet and the Internet and ran TCP/IP as well).

  3. Re:Impressive. by soulsteal · · Score: 3, Funny

    Studying comes after Kernel Hacking and right before Binge Drinking. If we're not lucky, then the Kernel Hacking would come after or during the Binge Drinking