Re: [PATCHv2] lib/bb: Add BB_SIGNATURE_LOCAL_DIRS_EXCLUDE to speed-up taskhash on directories

[Mark Hatle <mark.hatle@kernel.crashing.org>]

On 11/15/19 10:29 AM, Peter Kjellerstedt wrote:
>> -----Original Message-----
>> From: bitbake-devel-bounces@lists.openembedded.org <bitbake-devel-
>> bounces@lists.openembedded.org> On Behalf Of Aníbal Limón
>> Sent: den 15 november 2019 15:47
>> To: bitbake-devel@lists.openembedded.org
>> Subject: [bitbake-devel] [PATCHv2] lib/bb: Add
>> BB_SIGNATURE_LOCAL_DIRS_EXCLUDE to speed-up taskhash on directories
>>
>> The new BB_SIGNATURE_LOCAL_DIRS_EXCLUDE allows you to specify a list
>> of directories to exclude when making taskhash, our specific case
>> is using SRC_URI that points local VCS directory.
>>
>> Use bb.fetch.module to set default to: "CVS .bzr .git .hg .osc .p4 .repo
>> .svn"
>>
>> Signed-off-by: Aníbal Limón <anibal.limon@linaro.org>
>> ---
>>  lib/bb/checksum.py        | 5 +++--
>>  lib/bb/fetch2/__init__.py | 4 ++--
>>  lib/bb/siggen.py          | 5 +++--
>>  3 files changed, 8 insertions(+), 6 deletions(-)
> 
> [cut]
> 
>> --- a/lib/bb/siggen.py
>> +++ b/lib/bb/siggen.py
>> @@ -123,6 +123,7 @@ class SignatureGeneratorBasic(SignatureGenerator):
>>
>>          self.unihash_cache = bb.cache.SimpleCache("1")
>>          self.unitaskhashes = self.unihash_cache.init_cache(data, "bb_unihashes.dat", {})
>> +        self.localdirsexclude = (data.getVar("BB_SIGNATURE_LOCAL_DIRS_EXCLUDE") or "CVS .bzr .git .hg .osc .p4 .repo .svn").split()
> 
> I don't like this construct, because if I do:
> 
> BB_SIGNATURE_LOCAL_DIRS_EXCLUDE_append = " some_dir"
> 
> it means that all of a sudden the SCM directories listed above will no 
> longer be excluded since BB_SIGNATURE_LOCAL_DIRS_EXCLUDE will now be 
> defined, but only contain " some_dir". Isn't it better to add:
> 
> BB_SIGNATURE_LOCAL_DIRS_EXCLUDE ??= "CVS .bzr .git .hg .osc .p4 .repo .svn"

I agree.. this really should be put into the bitbake.conf file in OE-core.  (I'd
also suggest adding it to the bitbake.conf file in bitbake itself, as an example.)

--Mark

> somewhere in OE-Core (and it can then also have a suitable 
> BB_SIGNATURE_LOCAL_DIRS_EXCLUDE[doc], though it seems BB_-variables 
> are only documented in meta/conf/documentation.conf)?
> 
> Alternatively, to keep the list above within bitbake, make it two 
> variables, one for the list of directories above that is not really 
> intended to be modified, and one for additional directories (which 
> should still be documented in meta/conf/documentation.conf).
> 
> //Peter
>