Re: [dpdk-stable] [EXT] Re: [dpdk-dev] [PATCH v2 01/13] security: fix verification of parameters

[Lukasz Wojciechowski <l.wojciechow@partner.samsung.com>]

W dniu 09.04.2020 o 13:13, Bruce Richardson pisze:
> On Thu, Apr 09, 2020 at 12:54:10PM +0200, Thomas Monjalon wrote:
>> 09/04/2020 12:14, Bruce Richardson:
>>> On Wed, Apr 08, 2020 at 07:51:35PM +0200, Thomas Monjalon wrote:
>>>> 08/04/2020 17:49, Lukasz Wojciechowski:
>>>>> Hi guys,
>>>>>
>>>>> I don't know what is the current status of "legacy" build using
>>>>> gnumakes, so I added the new DEBUG flag to config just as it was done in
>>>>> other libs like eventdev.
>>>>> Many guides still point config files as the one that should be changed
>>>>> in order to enable some features, so I thought I should add it there.
>>>>>
>>>>> If I understand well the official build system now is the one based on
>>>>> using meson and ninja, however it hasn't got anything similar to the
>>>>> gnamakefiles system, e.g.
>>>>> in the meson.build file for libraries all the libraries have build
>>>>> variable set to true and there are few ifs that check it, but as it's
>>>>> set to true all libraries build always.
>>>>> And each library considered there defines RTE_LIBRTE_[LIBRARY_NAME].
>>>>> It's kind of weird.
>>>>>
>>>>>      foreach l:libraries
>>>>>      *    build = true**
>>>>>      *    reason = '<unknown reason>' # set if build == false to explain why
>>>>>           ...
>>>>>      *    if not build*
>>>>>               dpdk_libs_disabled += name
>>>>>               set_variable(name.underscorify() + '_disable_reason', reason)
>>>>>           else
>>>>>               enabled_libs += name
>>>>>      *dpdk_conf.set('RTE_LIBRTE_' + name.to_upper(), 1)*
>>>>>           ...
>>>>>
>>>>> Have you think about reusing config files in meson configuration and
>>>>> have a single point of configuration? Of course all meson flags can
>>>>> overwrite the default config.
>>>> This is on purpose.
>>>> We are removing most of compile-time options with meson.
>>>>
>>>> I think we can use a global option for debug-specific code.
>>>> Bruce, what do you recommend?
>>>>
>>> Meson has a built-in global debug setting which could be used. However,
>>> that may be too course-grained. If that is the case there are a couple of
>>> options:
>>>
>>> 1 Each library can have it's own debug flag defined, which is set on
>>>    the commandline in CFLAGS. Can be done right now - just reuse any of the
>>>    debug variables in the existing make config files (stripping off the
>>>    CONFIG_), e.g. CFLAGS=-DRTE_MALLOC_DEBUG
>>> 2 Since that is perhaps not the most usable - though easiest to implement -
>>>    we can look to add a general debug option (or couple of options) in
>>>    meson, e.g. debug_libs=, debug_drivers=, where each option takes a list of
>>>    libs or drivers to pass the debug flags to. This will require a little
>>>    work in the meson build infrastructure, but is not that hard. The harder
>>>    part is standardizing the debug flags across all components.
>>>
>>> The advantage of #1 is that it works today and just needs some
>>> documentation for each lib/driver what it's debug flags are. The advantage
>>> of #2 is more usability, but it requires a lot more work to standardize
>>> IMHO.
>> In this case, we need a general option as the one already provided by meson.
>> It means: "I am not in production, I want to see anything behaving wrong
>> in the datapath."
>> "Anything" means we don't need a per-library switch.
>> And for the other needs (out of fast path), we have a new function:
>> 	rte_log_can_log(mylogtype, RTE_LOG_DEBUG)
>>
> To use the general option in meson something like below is probably all
> that is needed to flag the debug build to all components:
>
> diff --git a/config/meson.build b/config/meson.build
> index 49482091d..b01cd1251 100644
> --- a/config/meson.build
> +++ b/config/meson.build
> @@ -176,6 +176,10 @@ endif
>   # add -include rte_config to cflags
>   add_project_arguments('-include', 'rte_config.h', language: 'c')
>
> +if get_option('debug')
> +       add_project_arguments('-DDEBUG', language: 'c')
> +endif
> +

This will conflict with DEBUG define for log level.

How about adding similar define in library meson.build file? , e.g

diff --git a/lib/librte_security/meson.build 
b/lib/librte_security/meson.build
index 5679c8b5c..ee92483c5 100644
--- a/lib/librte_security/meson.build
+++ b/lib/librte_security/meson.build
@@ -4,3 +4,7 @@
  sources = files('rte_security.c')
  headers = files('rte_security.h', 'rte_security_driver.h')
  deps += ['mempool', 'cryptodev']
+
+if get_option('debug')
+ add_project_arguments('-DRTE_LIBRTE_SECURITY_DEBUG', language: 'c')
+endif


>   # enable extra warnings and disable any unwanted warnings
>   warning_flags = [
>          # -Wall is added by meson by default, so add -Wextra only
>   
>
-- 

Lukasz Wojciechowski
Principal Software Engineer

Samsung R&D Institute Poland
Samsung Electronics
Office +48 22 377 88 25
l.wojciechow@partner.samsung.com