Re: of balloon drivers and such

[Jean-Yves Migeon <jeanyves.migeon%free.fr@localhost>]

On Sat, 1 May 2010 15:46:49 +0530, "Cherry G. Mathew"
<cherry.g.mathew%gmail.com@localhost> wrote:
> Hello,
> 
> ftp://ftp.netbsd.org/pub/NetBSD/misc/cherry/balloon/
> 
> I spent a bit more time messing around with this. If people could test
> it on real systems that'd be a real help.
> 
> I have no idea how it performs under real life work loads.

Very quick overview (PAE keeps me busy, did not test it, sorry):
- x86_btop and XPMAP_OFFSET: use xpmap_ptom()/mtop() directly instead, for
portability (most Xen drivers (balloon is one), will eventually move to
dev/xen).
- protect xpmap_phys_to_machine_mapping access with splvm(), preferably in
"sane" places (before entering a loop, for example), as flaglock mtx is
IPL_NONE and kthread is PRI_NONE.

-- 
Jean-Yves Migeon
jeanyves.migeon%free.fr@localhost