Re: [PATCH] xen/tmem: Fix uses of unmatched __map_domain_page()

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Fri, Dec 06, 2013 at 02:45:02PM +0800, Bob Liu wrote:
> 
> On 12/04/2013 05:00 AM, Konrad Rzeszutek Wilk wrote:
> > On Wed, Nov 27, 2013 at 02:55:04PM +0000, Andrew Cooper wrote:
> >> I noticed this while looking through tmem_xen.h with regards to the
> >> recently-discovered Coverity issues.  As the issue was not noticed or
> >> referenced in Bob's cleanup series, I figured it was fair game, given its
> >> severity.
> >>
> >> __map_domain_page() *must* be matched with an unmap_domain_page().  These five
> >> static inline functions each map a page (or two), then throw away the context
> >> needed to unmap it.
> > 
> > I was trying to figure out how it worked before. I had been running with
> > tze enabled (I hope!) and I did not trigger any mapcache exhaustion.
> > 
> > Ah wait, I had been on my nighly regression system  - which has some
> > guests that use tmem but they don't create any load fast enough.
> > 
> > Let me queue this up and test it. Bob, would appreciate you testing
> > it too - just in case.
> > 
> 
> I've done the testing with this patch on trunk and I didn't see any problem.
> 
> Both dedup and tze are enabled in my testing and I'm sure they were in use.
> 
> [root@ca-test65 bob.liu]# xm tmem-list --long --all |
> /usr/sbin/xen-tmem-list-parse
> WARNING: xend/xm is deprecated.
> total tmem ops=4139783 (errors=5461) -- tmem pages avail=20918
> datastructs: objs=1039 (max=2130) pgps=32422 (max=53149) nodes=1994
> (max=2803) pages=26709 (max=46611) pcds=13776 (max=35691) deduped:
> avg=6.35% (curr=35.47%) tze savings=4.34%

Thank you!

Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Jan, Andrew,

Do you guys want me to repost this with the 'Tested-by: Bob Liu
<bobliu@oracle.com> tag and my tag so it can go straight away in the
code or would you prefer to wait until I have a git branch ready?



> 
> Thanks,
> -Bob