Re: Giant and MPSAFE

From: Kris Kennaway (kris_at_obsecurity.org)
Date: 10/17/04

  • Next message: Kris Kennaway: "Re: TCFS on FreeBSD (fwd)"
    Date: Sun, 17 Oct 2004 11:55:03 -0700
    To: Ben Paley <ben@spooty.net>
    
    
    

    On Sun, Oct 17, 2004 at 12:38:04PM +0100, Ben Paley wrote:
    > Hello,
    >
    > bash-2.05b$ uname -a
    > FreeBSD potato.hogsedge.net 5.3-BETA5 FreeBSD 5.3-BETA5 #0: Mon Sep 20
    > 07:49:52 BST 2004 root@potato.hogsedge.net:/usr/obj/usr/src/sys/POTATO
    > i386
    >
    > I've just noticed a nasty looking message at boot:
    >
    > WARNING: debug.mpsafenet forced to 0 as aio requires Giant
    > WARNING: MPSAFE network stack disabled, expect reduced performance.
    >
    > And then subsequently there are a good few references to things being (from
    > memory)
    >
    > [GIANT LOCKED]
    >
    > Anyone have any idea what this is about, and if it's actually bad, and how I
    > can sort it out?

    Some subsystems have not yet been modified so they take advantage of
    multiple processors. aio is one of them, and because it interlinks
    with the network subsystem, if you have it in your kernel you can't
    make use of smp in the entire network stack.

    It's unlikely that you really need aio since it's still experimental
    code, so you can just compile it out of your kernel.

    Kris

    
    



  • Next message: Kris Kennaway: "Re: TCFS on FreeBSD (fwd)"

    Relevant Pages

    • Re: Reminder: NET_NEEDS_GIANT, debug.mpsafenet going away in 7.0
      ... These shimmed allowed Giant to be re-enabeld over the network stack as a result of linking in a service that required Giant, or by setting the debug.mpsafenet variable to 1. ... WARNING: Network stack Giant-free, but aio requires Giant. ...
      (freebsd-arch)
    • Re: Reminder: NET_NEEDS_GIANT, debug.mpsafenet going away in 7.0
      ... These shimmed allowed Giant to be re-enabeld over the network stack as a result of linking in a service that required Giant, or by setting the debug.mpsafenet variable to 1. ... WARNING: Network stack Giant-free, but aio requires Giant. ...
      (freebsd-current)
    • Re: -BETA6 panic with xorp multicast routing daemon
      ... > been forced by running with a kernel component that relies on Giant over ... debug.mpsafenet forced to 0 as ipsec requires Giant ... WARNING: MPSAFE network stack disabled, ...
      (freebsd-current)
    • Giant and MPSAFE
      ... debug.mpsafenet forced to 0 as aio requires Giant ... WARNING: MPSAFE network stack disabled, ...
      (freebsd-questions)
    • Re: MPSAFE network stack disabled
      ... Pet Farrari writes: ... "WARNING: MPSAFE network stack disabled, ...
      (comp.unix.bsd.freebsd.misc)