On 01/05/2011 07:28 PM, Peter Zijlstra wrote:
On Wed, 2011-01-05 at 19:19 +0200, Avi Kivity wrote: > On 01/05/2011 07:15 PM, Peter Zijlstra wrote: > > On Wed, 2011-01-05 at 19:10 +0200, Avi Kivity wrote: > > > On 01/04/2011 08:04 PM, Peter Zijlstra wrote: > > > > This definitely wants to be EXPORT_SYMBOL_GPL() and if it were possible > > > > I'd make it so only kvm.o could use it. It really sucks that kvm is a > > > > module. > > > > > > Why does it suck? I mean apart from the "virtualization is crap" song. > > > > Because it needs hooks all over the core kernel, like this yield_to() > > stuff. Exporting this might lead to others wanting to use it too. > > Well, it's very convenient for development (modprobe vs. reboot). Get a machine that boots fast ;-), it might be because I've never worked on anything modular, but typically stuff crashes when I got it wrong, in which case you're forced to power-cycle anyway.
I often get by with just guest crashes. Or maybe it oopses, I look around, then reboot at my leisure.
> What hooks do you object to? Don't really keep a list, but every now and again see something that makes me think that ought not be exported. > mmu notifiers are useful for some drivers, sched > notifiers are useful for cmwq and possibly perf? Both use explicit function calls because its easier to read the code and faster.
I doubt it's measurable, especially for perf with the msr tweaking it does. Tejun, why did you end up not using preempt_notifiers in cmwq? -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
