On Fri, Jan 11, 2019 at 12:20:45AM +0100, Andrea Parri wrote: > > > I'm not all that exited about spreading version requirements in the > > > source: we report this requirement in our README, and apparently we > > > already struggle to keep this information up-to-date. So what about > > > squashing something like the below (assume that 7.52 will be released > > > by the time this patch hit mainline; if this won't be the case, we > > > may consider using the development version 7.51+6)? notice that this > > > also removes an (obsolete, at this point) comment from lock.cat. > > > > Sounds like a very good point to me! > > > > Should have pointers in the various files to the README file? Or maybe > > get people used to using scripting that checks versions? Or maybe > > after answering questions for some time, people will get used to > > checking versions? > > As discussed off-list: I have no strong opinion on this regard, well, > except that I think we ought to fix the README, somehow (consider my > diff below as a first proposal). Akira actually preceded me on this > and suggested another solution [1]. > > Andrea > > [1] http://lkml.kernel.org/r/04d15c18-d210-e3da-01e2-483eff135cb7@xxxxxxxxx My concern with this approach is that it seems to me to implicitly promise that herd will provide backwards compatibility, which is a real pain to test, let alone to provide. Yes, the latest version of herd probably supports latest mainline, but will five-years-from-now herd work correctly on the .bell, .cat, and .def files from current mainline? Thanx, Paul > > > Andrea > > > > > > diff --git a/tools/memory-model/README b/tools/memory-model/README > > > index 9d7d4f23503fd..b362a41358fa1 100644 > > > --- a/tools/memory-model/README > > > +++ b/tools/memory-model/README > > > @@ -20,8 +20,8 @@ that litmus test to be exercised within the Linux kernel. > > > REQUIREMENTS > > > ============ > > > > > > -Version 7.49 of the "herd7" and "klitmus7" tools must be downloaded > > > -separately: > > > +Version 7.52 or higher of the "herd7" and "klitmus7" tools must be > > > +downloaded separately: > > > > > > https://github.com/herd/herdtools7 > > > > > > diff --git a/tools/memory-model/linux-kernel.cat b/tools/memory-model/linux-kernel.cat > > > index 95bf45f1215fc..8dcb37835b613 100644 > > > --- a/tools/memory-model/linux-kernel.cat > > > +++ b/tools/memory-model/linux-kernel.cat > > > @@ -1,7 +1,5 @@ > > > // SPDX-License-Identifier: GPL-2.0+ > > > (* > > > - * Requires herd version 7.51+6 or higher. > > > - * > > > * Copyright (C) 2015 Jade Alglave <j.alglave@xxxxxxxxx>, > > > * Copyright (C) 2016 Luc Maranget <luc.maranget@xxxxxxxx> for Inria > > > * Copyright (C) 2017 Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>, > > > diff --git a/tools/memory-model/lock.cat b/tools/memory-model/lock.cat > > > index 305ded17e7411..a059d1a6d8a29 100644 > > > --- a/tools/memory-model/lock.cat > > > +++ b/tools/memory-model/lock.cat > > > @@ -6,9 +6,6 @@ > > > > > > (* > > > * Generate coherence orders and handle lock operations > > > - * > > > - * Warning: spin_is_locked() crashes herd7 versions strictly before 7.48. > > > - * spin_is_locked() is functional from herd7 version 7.49. > > > *) > > > > > > include "cross.cat" > > > > > > > > > > > > > + * > > > > * Copyright (C) 2015 Jade Alglave <j.alglave@xxxxxxxxx>, > > > > * Copyright (C) 2016 Luc Maranget <luc.maranget@xxxxxxxx> for Inria > > > > * Copyright (C) 2017 Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>, > > > > diff --git a/tools/memory-model/linux-kernel.def b/tools/memory-model/linux-kernel.def > > > > index 1d6a120cde14..0c3f0ef486f4 100644 > > > > --- a/tools/memory-model/linux-kernel.def > > > > +++ b/tools/memory-model/linux-kernel.def > > > > @@ -49,7 +49,7 @@ synchronize_rcu_expedited() { __fence{sync-rcu}; } > > > > > > > > // SRCU > > > > srcu_read_lock(X) __srcu{srcu-lock}(X) > > > > -srcu_read_unlock(X,Y) { __srcu{srcu-unlock}(X); } > > > > +srcu_read_unlock(X,Y) { __srcu{srcu-unlock}(X,Y); } > > > > synchronize_srcu(X) { __srcu{sync-srcu}(X); } > > > > > > > > // Atomic > > > > -- > > > > 2.17.1 > > > > > > > > > >
