Re: [PATCH v3 3/3] selftests: pidfd: add tests for PIDFD_SELF_*

[Shuah Khan <skhan@linuxfoundation.org>]

On 5/6/25 15:34, John Hubbard wrote:
> On 5/6/25 2:18 PM, Shuah Khan wrote:
>> On 5/1/25 05:42, Peter Zijlstra wrote:
>>> On Wed, Oct 16, 2024 at 07:14:34PM -0700, John Hubbard wrote:
>>>> On 10/16/24 3:06 PM, Lorenzo Stoakes wrote:
>>>>> On Wed, Oct 16, 2024 at 02:00:27PM -0600, Shuah Khan wrote:
>>>>>> On 10/16/24 04:20, Lorenzo Stoakes wrote:
>>>> ...
>>> Please fix this fucking selftests shit to just build. This is unusable
>>> garbage.
>>

Peter, John,

There seems to be confusion regarding  KHDR_INCLUDES. Tests don't have
to use KHDR_INCLUDES if they don't want to.

There are 4623 test Makefiles (excluding the main Makefile) under selftests/.
Out of those 73 Makefiles reference KHDR_INCLUDES exported by lib.mk and
selftests/Makefile. The rest are happy with system headers.

The support for this KHDR_INCLUDES was added just for the case when a new
test depends on header change. This is the reason why only a few
test Makefiles use it. When test rings ran into issues related to
dependencies between header changes, we recommended installing headers
to solve the problem and introduced KHDR_INCLUDES so test Makefiles
can use it in their Makefiles overriding the framework defaults.

If your test doesn't need it, you can simply stop referencing it or
use the approach used in mm test.

It is a manual step. Works well for developers who know what they are doing.
This isn't ideal for test rings. This isn't an ideal solution really.
It works for the mm developers.

# In order to use newer items that haven't yet been added to the user's system
# header files, add $(TOOLS_INCLUDES) to the compiler invocation in each
# each selftest.
# You may need to add files to that location, or to refresh an existing file. In
# order to do that, run "make headers" from $(top_srcdir), then copy the
# header file that you want from $(top_srcdir)/usr/include/... , to the matching
# subdir in $(TOOLS_INCLUDE).
TOOLS_INCLUDES := -isystem $(top_srcdir)/tools/include/uapi

The issues Peter is seeing regarding KHDR_INCLUDES in the following
tests can be easily fixed by simply changing the test Makefile. These
aren't framework related.

kvm/Makefile.kvm:	-I ../rseq -I.. $(EXTRA_CFLAGS) $(KHDR_INCLUDES)
x86/Makefile:CFLAGS := -O2 -g -std=gnu99 -pthread -Wall $(KHDR_INCLUDES)
futex/functional/Makefile:INCLUDES := -I../include -I../../ $(KHDR_INCLUDES)
futex/functional/Makefile:CFLAGS := $(CFLAGS) -g -O2 -Wall -pthread $(INCLUDES) $(KHDR_INCLUDES)

You can make the change to remove the reference to KHDR_INCLUDES.
If don't have the time/bandwidth to do it, I will take care of it.

If test build fails, you can then figure out how to address that.
Hopefully build issues related to header changes are infrequent.

thanks,
-- Shuah