[bitbake-devel] [PATCH 1/1] data_smart.py: make use of expand cache in getVar()

[Richard Purdie]

On Mon, 2011-08-29 at 21:07 +0800, Xu, Dongxiao wrote:
> Hi Richard,
> 
> > -----Original Message-----
> > From: Richard Purdie [mailto:richard.purdie at linuxfoundation.org]
> > Sent: Monday, August 29, 2011 8:55 PM
> > To: Xu, Dongxiao
> > Cc: bitbake-devel at lists.openembedded.org
> > Subject: Re: [bitbake-devel] [PATCH 1/1] data_smart.py: make use of expand
> > cache in getVar()
> > 
> > On Mon, 2011-08-29 at 15:33 +0800, Dongxiao Xu wrote:
> > > Currently if passing expand=True to getVar() function, it will pass
> > > the handling to getVarFlag(), which doesn't get any benefit from the
> > > expand cache.
> > >
> > > Call the expand() function separately in getVar() to make use of the
> > > expand cache, which can decrease the parsing time by 40%.
> > > (from current 49s to 27s)
> > >
> > > Signed-off-by: Dongxiao Xu <dongxiao.xu at intel.com>
> > > ---
> > >  lib/bb/data_smart.py |    7 ++++++-
> > >  1 files changed, 6 insertions(+), 1 deletions(-)
> > >
> > > diff --git a/lib/bb/data_smart.py b/lib/bb/data_smart.py index
> > > 301f9e3..d8ba24f 100644
> > > --- a/lib/bb/data_smart.py
> > > +++ b/lib/bb/data_smart.py
> > > @@ -268,7 +268,12 @@ class DataSmart(MutableMapping):
> > >          self.dict[var]["content"] = value
> > >
> > >      def getVar(self, var, expand=False, noweakdefault=False):
> > > -        return self.getVarFlag(var, "content", expand, noweakdefault)
> > > +        value = self.getVarFlag(var, "content", False, noweakdefault)
> > > +
> > > +        # Call expand() separately to make use of the expand cache
> > > +        if expand and value:
> > > +            return self.expand(value, var)
> > > +        return value
> > >
> > 
> > Why can't we have getVarFlag use the expand cache?
> 
> For expand cache, the format is a list: expand_cache[varname].
> It doesn't contain information of flag values.

Good point.

I'm left wondering why we don't key that cache on the unexpanded value
rather than a specific variable name (or name+flag).

I'll take this patch but its something we should consider...

Cheers,

Richard