Re: [PATCH 0/3] tools/memory-model, Documentation/litmus-test: Sort out location of litmus test and README

From: Akira Yokosawa
Date: Tue May 12 2020 - 10:39:27 EST


On Tue, 12 May 2020 07:19:44 -0700, Paul E. McKenney wrote:
> On Tue, May 12, 2020 at 08:19:36AM -0400, Joel Fernandes wrote:
>> On Tue, May 12, 2020 at 08:50:45PM +0900, Akira Yokosawa wrote:
>> [...]
>>>> I think on top of this patch, I'd like to add a reference to the to the
>>>> litmus test in tools/memory-model/ from Documentation/rcu/.
>>>
>>> Sounds reasonable to me. But for most people, it never changes its location.
>>> Please find inline comments below.
>>>
>>>>
>>>> Just to mention my rationale for Documentation/litmus-tests/rcu/, I was
>>>> basically looking for a central place for RCU related litmus tests in the
>>>> kernel sources and the idea of this new directory came up.
>>>>
>>>> For Akira's series,
>>>> Acked-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
>>>
>>> Thank you!
>>>
>>>>
>>>> And could we add the following patch on top of Akira's series so we still
>>>> maintain a reference to the moved RCU test?>
>>>> ---8<-----------------------
>>>>
>>>> From 52fdb57551cc769d8bd690f4f2b22de36ddece99 Mon Sep 17 00:00:00 2001
>>>> From: "Joel Fernandes (Google)" <joel@xxxxxxxxxxxxxxxxx>
>>>> Date: Mon, 11 May 2020 22:06:46 -0400
>>>> Subject: [PATCH] docs: litmus-tests: Clarify about the RCU pre-initialization
>>>> test
>>>>
>>>> Since this test was moved to tools/memory-model/, make sure that it is
>>>> at least referenced from Documentation/litmus-tests/'s README.
>>>>
>>>> Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
>>>> ---
>>>> Documentation/litmus-tests/README | 6 ++++--
>>>> 1 file changed, 4 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/Documentation/litmus-tests/README b/Documentation/litmus-tests/README
>>>> index ac0b270b456c1..53f09e74734a4 100644
>>>> --- a/Documentation/litmus-tests/README
>>>> +++ b/Documentation/litmus-tests/README
>>>> @@ -11,7 +11,6 @@ tools/memory-model/README.
>>>>
>>>> atomic (/atomic derectory)
>>>> --------------------------
>>>> -
>>>> Atomic-RMW+mb__after_atomic-is-stronger-than-acquire.litmus
>>>> Test that an atomic RMW followed by a smp_mb__after_atomic() is
>>>> stronger than a normal acquire: both the read and write parts of
>>>> @@ -23,8 +22,11 @@ Atomic-RMW-ops-are-atomic-WRT-atomic_set.litmus
>>>>
>>>> RCU (/rcu directory)
>>>> --------------------
>>>> -
>>>
>>> I loosely followed the convention of ReST documents in putting these empty
>>> lines. But I don't mind if they are removed.
>>>
>>>> RCU+sync+read.litmus
>>>> RCU+sync+free.litmus
>>>> Both the above litmus tests demonstrate the RCU grace period guarantee
>>>> that an RCU read-side critical section can never span a grace period.
>>>> +
>>>> +MP+onceassign+derefonce.litmus (moved to tools/memory-model/litmus-tests/)
>>>
>>> As I said above, for those who don't follow developments in the lkmm branch,
>>> MP+onceassign+derefonce.litmus stays in tools/memory-model/litmus-tests/.
>>> So,
>>>
>>> +MP+onceassign+derefonce.litmus (under tools/memory-model/litmus-tests/)
>>>
>>> looks better to me.
>>
>> Yes it stays under tools/.. but is referenced here. Sounds like you agree and
>> the only change from my follow-up patch that you want is to change "moved to"
>> to "under".
>>
>> If so, Paul do you mind applying my patch and fixing this up? Or do you want
>> to apply Akira's 3-patch series first and then have me send you another one
>> on top?
>
> Let's get something that you, Akira, and Alan are good with, then I will
> apply that, either on top of or in place of the current commits (just
> tell me which).

OK.
I'm submitting a patch [4/3] with Alan's suggested-by and Joel's and my
co-developed-by tags.
The explanation under tools/memory-model/litmus-tests/README also need the same
rewording.

Thanks, Akira

>
> Thanx, Paul
>