[dpdk-dev] [PATCH v2] mk: optimize directory dependencies

[Ferruh Yigit]

On 3/30/2017 9:51 AM, Olivier Matz wrote:
> Hi Ferruh,
> 
> On Tue, 28 Mar 2017 11:34:35 +0100, Ferruh Yigit <ferruh.yigit at intel.com> wrote:
>> On 3/24/2017 1:21 PM, Olivier Matz wrote:
>>> Before this patch, the management of dependencies between directories
>>> had several issues:
>>>
>>> - the generation of .depdirs, done at configuration is slow: it can take
>>>   more than one minute on some slow targets (usually ~10s on a standard
>>>   PC without -j).
>>>
>>> - for instance, it is possible to express a dependency like:
>>>   - app/foo depends on lib/librte_foo
>>>   - and lib/librte_foo depends on app/bar
>>>   But this won't work because the directories are traversed with a
>>>   depth-first algorithm, so we have to choose between doing 'app' before
>>>   or after 'lib'.
>>>
>>> - the script depdirs-rule.sh is too complex.
>>>
>>> - we cannot use "make -d" for debug, because the output of make is used for
>>>   the generation of .depdirs.
>>>
>>> This patch moves the DEPDIRS-* variables in the upper Makefile, making
>>> the dependencies much easier to calculate. A DEPDIRS variable is still
>>> used to process library dependencies in LDLIBS.
>>>
>>> After this commit, "make config" is almost immediate.
>>>
>>> Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
>>> Tested-by: Robin Jarry <robin.jarry at 6wind.com>
>>> Tested-by: Jerin Jacob <jerin.jacob at caviumnetworks.com>  
>>
>> <...>
>>
>>>  DIRS-$(CONFIG_RTE_LIBRTE_PORT) += librte_port
>>> +DEPDIRS-librte_port := librte_eal librte_mbuf librte_mempool librte_ether
>>> +DEPDIRS-librte_port += librte_ip_frag librte_sched librte_kni  
>>                                                          ^
>> ---------------------------------------------------------+
>>
>> <...>
>>
>>> diff --git a/lib/librte_port/Makefile b/lib/librte_port/Makefile
>>> index 44fa73520..76629a13a 100644
>>> --- a/lib/librte_port/Makefile
>>> +++ b/lib/librte_port/Makefile  
>> <...>
>>> -ifeq ($(CONFIG_RTE_LIBRTE_KNI),y)
>>> -DEPDIRS-$(CONFIG_RTE_LIBRTE_PORT) += lib/librte_kni
>>> -endif  
>>
>> This check needs to be reflected to new method, otherwise causing build
>> errors for i686 target.
>>
> 
> Did you notice an error? I see no error it with:
> 
>     make config T=x86_64-native-linuxapp-gcc
>     sed -i 's,CONFIG_RTE_LIBRTE_KNI=y,# CONFIG_RTE_LIBRTE_KNI is not set,' build/.config
>     make -j8
> 
> 
> I think it is not a problem, the DEPDIRS-* variable only gives an
> ordering directive, which should be ok even if kni is not compiled.

Can you please test shared library build, I am getting following error:

== Build lib/librte_port
  LD librte_port.so.3.1
/usr/bin/ld: cannot find -lrte_kni
collect2: error: ld returned 1 exit status
.../mk/rte.lib.mk:127: recipe for target 'librte_port.so.3.1' failed
make[3]: *** [librte_port.so.3.1] Error 1
.../mk/rte.subdir.mk:63: recipe for target 'librte_port' failed

> 
> 
> Regards,
> Olivier
>