Re: [PATCH] package.bbclass: allow using EXCLUDE_FROM_SHLIBS for subpackages

Andrii Bordunov
2017-03-16T15:17:13Z

Hi Richard,

Sorry, my Python knowledge is quite basic. I'm sure it's possible to
have a (global?) EXCLUDE_FROM_SHLIBS list holding subpackage names, but
how it could lead to performance improvement? It would also need some
check for every subpackage.
Could you please give more details?
And what do you mean under "all packages"? The intent is like opposite,
to split package operations, not to gather.

As for False parameter to getVar, OK, I just used existing
EXCLUDE_FROM_SHLIBS example (seems fixed now).

In the meantime tried to make a quick and dirty profiling like following:

bitbake -c package glibc
bitbake -c clean glibc
python -m cProfile -s cumtime /mnt/src/oe/distro/bitbake/bin/bitbake
-c package glibc > result.txt

Result is below. If got it right, there are 3833 getVar calls with total
time 0.025 second (including subcalls).
This gives ~6.5 microsecond duration of one call (incl subcalls). Not a lot.
This is only a partial rebuild of one package of course.
Also tried to do all of this with and without my patch, but getVar calls
number stays exactly the same (w/o modifying glibc recipe, but anyway).

NOTE: Tasks Summary: Attempted 314 tasks of which 314 didn't need to
be rerun and all succeeded.
672869 function calls (667640 primitive calls) in 12.912 seconds
Ordered by: cumulative time
ncalls tottime percall cumtime percall filename:lineno(function)
1 0.001 0.001 12.913 12.913 bitbake:25(<module>)
1 0.001 0.001 12.082 12.082 main.py:320(bitbake_main)
1 0.005 0.005 11.494 11.494 knotty.py:253(main)
250 11.476 0.046 11.476 0.046 {method 'poll' of
'_multiprocessing.Connection' objects}
...
4481/4046 0.007 0.000 0.026 0.000
data_smart.py:666(getVarFlag)
...
3833/3719 0.002 0.000 0.025 0.000 data_smart.py:569(getVar)
...
1338 0.002 0.000 0.003 0.000
data_smart.py:805(getVarFlags)

Thank you,
Andrii

On 16.11.16 12:47, Richard Purdie wrote:
> On Mon, 2016-10-10 at 20:02 +0300, Andrii Bordunov wrote:
>> Some packages containing shared libraries might be registered
>> as shlib providers when they shouldn't (for example, the lib is for
>> their private use and must not generate any dependency).
>>
>> EXCLUDE_FROM_SHLIBS is targeted at that, but it could be set
>> for entire recipe only.
>>
>> This patch expands EXCLUDE_FROM_SHLIBS usage, so now it's possible
>> to set it in a style similar with RDEPENDS. For example:
>> EXCLUDE_FROM_SHLIBS_${PN}-ptest = "1"
>>
>> Signed-off-by: Andrii Bordunov <aborduno@cisco.com>
>> ---
>> meta/classes/package.bbclass | 12 ++++++++++--
>> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> My main concern here is actually performance. For a package with many
> sub packages you just added many calls to getVar when that getVar is
> extremely unlikely to find any value. Whilst not hugely slow, that
> operation isn't trivial and hard to fix later.
>
> I'm wondering if we could support the syntax
>
> EXCLUDE_FROM_SHLIBS = "${PN}-ptest"
>
> and then have "1", used in a couple of places as the special value to
> mean all packages?
>
> Also please use False, not 0 as the parameter to getVar.
>
> Cheers,
>
> Richard
>