[Buildroot] [PATCH] bind: fix intermittent build issues with high BR2_JLEVEL

[Thomas Petazzoni]

Jan,

On Fri, 6 Nov 2015 08:04:35 +0100, Jan Heylen wrote:

> > I am not sure it is appropriate to send a patch in the name of someone
> > else. Maybe you're taking one of Peter's previous commit, and
> > re-applying it, but the context is different, so I believe it should be
> > under your own name.
> >
> OK, just wanted to point out it is the same issue (and the same solution).

OK.


> make[1]: Leaving directory `<CUT>/output/build/bind-9.9.7'
> make: *** [<CUT>/output/build/bind-9.9.7/.stamp_built] Error 2
> 
> How often are you able to reproduce it ? On what type of build machine ?
> >
> 
> We are on the  2015.05, Released May 31st, 2015 Buildroot release.

On master, we updated bind to 9.9.8. Do you also reproduce the issue
with bind 9.9.8 ?

What I find weird is that our autobuilder infrastructure generally
catches pretty well the parallel build issues. And we currently have
zero failures on bind 9.9.7 and bind 9.9.8:

  http://autobuild.buildroot.org/?reason=bind-9.9.7
  http://autobuild.buildroot.org/?reason=bind-9.9.8


> We do build multiple defconfigs (up to 8) (in separate buildroot working
> folders) at once on the same machine. But I see from the buildroot output
> that BR2_JLEVEL is set to '9' (cores +1) for each of these jobs?

That's expected if you have left BR2_JLEVEL to its default of 0.

> >>> bind 9.9.7 Building
> PATH="<CUT>/output/host/bin:<CUT>/output/host/sbin:<CUT>/output/host/usr/bin:<CUT>/output/host/usr/sbin:/usr/local/bin:/usr/bin"
>  /usr/bin/make -j9  -C <CUT>/output/build/bind-9.9.7/
> make[1]: Entering directory `<CUT>/output/build/bind-9.9.7'
> making all in <CUT>/output/build/bind-9.9.7/make
> 
> 
> Maybe the exact condition is to have multiple buildroot jobs (8) on 8 cores
> with BR2_JLEVEL set to 8 (so 8*8 = 64 'jobs').
> 
> So we might optimize that on our side ;-), but still it shouldn't trigger
> this error?

It should trigger this error indeed.

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com