Re: [PATCH 00/45] ArmVirtPkg, OvmfPkg: list module-internal headers in INF files

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

On 11 March 2018 at 11:48, Laszlo Ersek <lersek@redhat.com> wrote:
> On 03/11/18 09:15, Ard Biesheuvel wrote:
>> Hi Laszlo,
>>
>> On 11 March 2018 at 01:48, Laszlo Ersek <lersek@redhat.com> wrote:
>>> Repo:   https://github.com/lersek/edk2.git
>>> Branch: hdr_inf_cleanup
>>>
>>> In
>>> <http://mid.mail-archive.com/E92EE9817A31E24EB0585FDF735412F56327F7D3@ORSMSX113.amr.corp.intel.com>,
>>> Mike explained why it's a good idea to list module-internal *.h files in
>>> the [Sources*] sections of the INF files:
>>>
>>> On 11/23/15 21:28, Kinney, Michael D wrote:
>>>> There are 2 reasons to list all source files used in a module build in
>>>> the [Sources] section.
>>>>
>>>> 1) Support incremental builds.  If a change to the .h file is made,
>>>>    then the module may  not be rebuilt if the .h file is not listed in
>>>>    [Sources]
>>>> 2) Support of UEFI Distribution Package distribution format.  The UPT
>>>>    tools that creates UDP packages uses the [Sources] section for the
>>>>    inventory of files.  If a file is missing, then it will not be
>>>>    included in the UDP file.
>>>
>>> In only two years and three-four months, I've finally come around
>>> addressing (1) under ArmVirtPkg and OvmfPkg.
>>
>> Thanks for doing this.
>>
>> However, while I highly appreciate your thoroughness and verbosity in
>> most cases, I do think you've crossed a line this time :-)
>>
>> Do we *really* need 4 different patches for CsmSupportLib, each adding
>> a single .h file to [Sources], with an elaborate description how it is
>> being used? If it is used, it needs to be listed, and if it is not, it
>> needs to be removed, that's all there is to it IMO.
>
> The structuring of the patch series reflects my thinking process and the
> work I did precisely. I didn't (couldn't) investigate multiple header
> files at once / in parallel; I investigated them one by one. It's easy
> to squash patches, and it's hard to split them, so I maintain that
> writing up and posting these patches one by one, in v1, was the right
> thing to do. Personally I find it much easier to read many trivial
> patches than half as many complex / divergent ones. If you prefer that I
> squash patches into one per module, I can do that (I'd wait for more
> feedback first though).
>
> Second, I disagree that it's as simple as "list it if it's used". I
> didn't just want to dump the .h filenames into the INF files; I wanted
> to see each time whether the use of the header file was justified in the
> first place -- this is not a given if there are multiple INF files in
> the same directory, or an INF file has architecture-specific Sources
> sections.
>
> For example, in patch 06/45, I removed "QemuLoader.h" from "Qemu.c", and
> "Qemu.c" is only built into one of the INF files under
> "OvmfPkg/AcpiPlatformDxe". (Ultimately I had to list "QemuLoader.h" in
> both INF files, in patch 07/45, due to "QemuFwCfgAcpi.c", which is built
> into both INFs.)
>
> For another example, in patch 37/45, I added "VbeShim.h" to
> [Sources.Ia32, Sources.X64], and not to another of the [Sources*]
> sections. The same applies to patch 17/45, where "X64/VirtualMemory.h"
> belongs under [Sources.X64] only.
>
> I find this is not as easy as it looks, and I meant to be thorough. If
> you don't have time to wade through the patches, I'll thank you if you
> ACK just the first three (ArmVirtPkg) patches.
>

Please understand that this is not criticism on your thinking process,
and I highly value the quality of your work in general, and for this
series in particular.

I am merely saying that it is not always necessary to share your
personal journey resulting in the patches at this level of detail,
simply because it doesn't scale.

In any case, I am happy with this to go in as is, if you prefer.

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>