[OE-core] [PATCH 4/4] native.bbclass: Use fixed DISTRO_FEATURES

[Richard Purdie]

On Fri, 2017-04-07 at 09:09 +0300, Jussi Kukkonen wrote:
> There seems to be no advantage to letting distro features affect
> native builds. There is a significant disadvantage: a change to
> DISTRO_FEATURES will trigger a lot of unnecessary native tasks. In a
> test like this:
>   $ bitbake core-image-minimal
>   # append " systemd" to DISTRO_FEATURES
>   $ bitbake core-image-minimal
> The latter build takes 44 minutes (28%) of cpu-time less with this
> patch (skipping 135 native tasks). Sadly wall clock time was not
> affected as glibc remains the bottleneck.
> 
> Set DISTRO_FEATURES to a fixed value for native recipes to avoid the
> unnecessary tasks: currently the default value is empty.
> 
> Do the variable setting in native_virtclass_handler() because
> otherwise
> it could still be overridden by appends and the feature backfilling.
> Shuffle the early returns so DISTRO_FEATURES gets set as long as
> the packagename ends with "-native".
> 
> Signed-off-by: Jussi Kukkonen <jussi.kukkonen at intel.com>
> ---
>  meta/classes/native.bbclass | 12 ++++++++----
>  meta/conf/bitbake.conf      |  2 ++
>  2 files changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/meta/classes/native.bbclass
> b/meta/classes/native.bbclass
> index 1919fbc..fbca4c6 100644
> --- a/meta/classes/native.bbclass
> +++ b/meta/classes/native.bbclass
> @@ -121,14 +121,18 @@ PATH_prepend = "${COREBASE}/scripts/native-
> intercept:"
>  SSTATE_SCAN_CMD ?= "${SSTATE_SCAN_CMD_NATIVE}"
>  
>  python native_virtclass_handler () {
> -    classextend = e.data.getVar('BBCLASSEXTEND') or ""
> -    if "native" not in classextend:
> -        return
> -
>      pn = e.data.getVar("PN")
>      if not pn.endswith("-native"):
>          return
>  
> +    # Set features here to prevent appends and distro features
> backfill
> +    # from modifying native distro features
> +    d.setVar("DISTRO_FEATURES", "${NATIVE_DISTRO_FEATURES}")
> +
> +    classextend = e.data.getVar('BBCLASSEXTEND') or ""
> +    if "native" not in classextend:
> +        return
> +
>      def map_dependencies(varname, d, suffix = ""):
>          if suffix:
>              varname = varname + "_" + suffix
> diff --git a/meta/conf/bitbake.conf b/meta/conf/bitbake.conf
> index 5e98d45..78a3470 100644
> --- a/meta/conf/bitbake.conf
> +++ b/meta/conf/bitbake.conf
> @@ -789,6 +789,8 @@ MACHINE_ESSENTIAL_EXTRA_RRECOMMENDS ?= ""
>  EXTRA_IMAGE_FEATURES ??= ""
>  IMAGE_FEATURES += "${EXTRA_IMAGE_FEATURES}"
>  
> +NATIVE_DISTRO_FEATURES ?= ""
> +
>  DISTRO_FEATURES_BACKFILL = "pulseaudio sysvinit bluez5 gobject-
> introspection-data ldconfig"
>  MACHINE_FEATURES_BACKFILL = "rtc qemu-usermode"

Thanks for working on this, looks good.

Most native variables are called XXX_NATIVE, not NATIVE_XXX so we might
want to make this match?

Also, one question. Does this have any effect on qemu-native? Does
qemu-native need/use x11 today?

Cheers,

Richard