From: Boqun Feng <boqun.feng@gmail.com>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: "Paul E. McKenney" <paulmck@kernel.org>,
linux-kernel@vger.kernel.org,
Andrea Parri <parri.andrea@gmail.com>,
Will Deacon <will@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Nicholas Piggin <npiggin@gmail.com>,
David Howells <dhowells@redhat.com>,
Jade Alglave <j.alglave@ucl.ac.uk>,
Luc Maranget <luc.maranget@inria.fr>,
Akira Yokosawa <akiyks@gmail.com>,
Daniel Lustig <dlustig@nvidia.com>,
Jonathan Corbet <corbet@lwn.net>,
linux-arch@vger.kernel.org, linux-doc@vger.kernel.org
Subject: Re: [RFC 0/3] tools/memory-model: Add litmus tests for atomic APIs
Date: Mon, 17 Feb 2020 09:27:34 +0800 [thread overview]
Message-ID: <20200217012734.GB69864@debian-boqun.qqnc3lrjykvubdpftowmye0fmh.lx.internal.cloudapp.net> (raw)
In-Reply-To: <Pine.LNX.4.44L0.2002161113320.30459-100000@netrider.rowland.org>
On Sun, Feb 16, 2020 at 11:16:50AM -0500, Alan Stern wrote:
> On Sun, 16 Feb 2020, Paul E. McKenney wrote:
>
> > On Sun, Feb 16, 2020 at 01:43:45PM +0800, Boqun Feng wrote:
> > > On Sat, Feb 15, 2020 at 07:25:50AM -0800, Paul E. McKenney wrote:
> > > > On Fri, Feb 14, 2020 at 10:27:44AM -0500, Alan Stern wrote:
> > > > > On Fri, 14 Feb 2020, Boqun Feng wrote:
> > > > >
> > > > > > A recent discussion raises up the requirement for having test cases for
> > > > > > atomic APIs:
> > > > > >
> > > > > > https://lore.kernel.org/lkml/20200213085849.GL14897@hirez.programming.kicks-ass.net/
> > > > > >
> > > > > > , and since we already have a way to generate a test module from a
> > > > > > litmus test with klitmus[1]. It makes sense that we add more litmus
> > > > > > tests for atomic APIs into memory-model.
> > > > >
> > > > > It might be worth discussing this point a little more fully. The
> > > > > set of tests in tools/memory-model/litmus-tests/ is deliberately rather
> > > > > limited. Paul has a vastly more expansive set of litmus tests in a
> > > > > GitHub repository, and I am doubtful about how many new tests we want
> > > > > to keep in the kernel source.
> > > >
> > > > Indeed, the current view is that the litmus tests in the kernel source
> > > > tree are intended to provide examples of C-litmus-test-language features
> > > > and functions, as opposed to exercising the full cross-product of
> > > > Linux-kernel synchronization primitives.
> > > >
> > > > For a semi-reasonable subset of that cross-product, as Alan says, please
> > > > see https://github.com/paulmckrcu/litmus.
> > > >
> > > > For a list of the Linux-kernel synchronization primitives currently
> > > > supported by LKMM, please see tools/memory-model/linux-kernel.def.
> > > >
> > >
> > > So how about I put those atomic API tests into a separate directory, say
> > > Documentation/atomic/ ?
> > >
> > > The problem I want to solve here is that people (usually who implements
> > > the atomic APIs for new archs) may want some examples, which can help
> > > them understand the API requirements and test the implementation. And
> > > litmus tests are the perfect tool here (given that them can be
> > > translated to test modules with klitmus). And I personally really think
> > > this is something the LKMM group should maintain, that's why I put them
> > > in the tools/memory-model/litmus-tests/. But I'm OK if we end up
> > > deciding those should be put outside that directory.
> >
> > Good point!
> >
> > However, we should dicuss this with the proposed beneficiaries, namely
> > the architecture maintainers. Do they want it? If so, where would
> > they like it to be? How should it be organized?
> >
Paul,
Well, I was simply motivated by the discuss on microblaze's atomic
implementation (which I pasted the link in this cover letter):
https://lore.kernel.org/lkml/20200213085849.GL14897@hirez.programming.kicks-ass.net/
, please see the last paragraph, Michal asking Peter for some tests. So
I think there is at least some one wanting this ;-)
> > In the meantime, I am more than happy to accept litmus tests into the
> > github archive.
> >
Thanks ;-)
> > So how would you like to proceed?
I think we are still at the discussion stage, so I'm happy to see
suggestions on where to put the litmus tests and which litmus tests
should be included.
>
> I think it makes sense to put Boqun's tests under Documentation/ rather
> than tools/. After all, their point is to document the memory model's
> requirements for operations on atomic_t's. They aren't meant to be
> examples or demos showing how to use herd or write litmus tests.
>
Alan,
Got it. I will create the Documentation/atomic directory and put the
litmus tests there in the next version.
Thank you both!
Regards,
Boqun
> Alan
>
prev parent reply other threads:[~2020-02-17 1:27 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-14 4:01 [RFC 0/3] tools/memory-model: Add litmus tests for atomic APIs Boqun Feng
2020-02-14 4:01 ` [RFC 1/3] Documentation/locking/atomic: Fix atomic-set litmus test Boqun Feng
2020-02-14 4:01 ` [RFC 2/3] tools/memory-model: Add a litmus test for atomic_set() Boqun Feng
2020-02-14 8:12 ` Andrea Parri
2020-02-14 10:40 ` Boqun Feng
2020-02-25 7:34 ` Boqun Feng
2020-02-25 13:01 ` Luc Maranget
2020-02-25 21:42 ` More on reader-writer locks Alan Stern
2020-02-26 9:46 ` Luc Maranget
2020-02-26 2:51 ` [RFC 2/3] tools/memory-model: Add a litmus test for atomic_set() Boqun Feng
2020-02-14 15:47 ` Alan Stern
2020-02-14 23:52 ` Boqun Feng
2020-02-17 11:02 ` Peter Zijlstra
2020-02-14 4:01 ` [RFC 3/3] tools/memory-model: Add litmus test for RMW + smp_mb__after_atomic() Boqun Feng
2020-02-14 6:15 ` Boqun Feng
2020-02-14 8:18 ` Andrea Parri
2020-02-14 8:20 ` Boqun Feng
2020-02-14 15:58 ` Alan Stern
2020-02-15 0:09 ` Boqun Feng
2020-02-14 9:55 ` [RFC 0/3] tools/memory-model: Add litmus tests for atomic APIs Peter Zijlstra
2020-02-14 10:20 ` Paul E. McKenney
2020-02-14 15:27 ` Alan Stern
2020-02-14 23:39 ` Boqun Feng
2020-02-15 15:25 ` Paul E. McKenney
2020-02-16 5:43 ` Boqun Feng
2020-02-16 12:06 ` Paul E. McKenney
2020-02-16 16:16 ` Alan Stern
2020-02-17 1:27 ` Boqun Feng [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200217012734.GB69864@debian-boqun.qqnc3lrjykvubdpftowmye0fmh.lx.internal.cloudapp.net \
--to=boqun.feng@gmail.com \
--cc=akiyks@gmail.com \
--cc=corbet@lwn.net \
--cc=dhowells@redhat.com \
--cc=dlustig@nvidia.com \
--cc=j.alglave@ucl.ac.uk \
--cc=linux-arch@vger.kernel.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luc.maranget@inria.fr \
--cc=npiggin@gmail.com \
--cc=parri.andrea@gmail.com \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.org \
--cc=stern@rowland.harvard.edu \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).