On Wed, Sep 05, 2018 at 05:01:17PM -0700, Paul E. McKenney wrote: > On Tue, May 29, 2018 at 09:17:13PM +0100, Will Deacon wrote: > > On Tue, May 29, 2018 at 05:11:07AM -0700, Paul E. McKenney wrote: > > > On Tue, May 29, 2018 at 10:30:50AM +0100, Will Deacon wrote: > > > > Hi Paul, > > > > > > > > On Fri, May 25, 2018 at 12:10:20PM -0700, Paul E. McKenney wrote: > > > > > This commit documents the scheme used to generate the names for the > > > > > litmus tests. > > > > > > > > > > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> > > > > > --- > > > > > README | 136 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++- > > > > > 1 file changed, 135 insertions(+), 1 deletion(-) > > > > > > > > Whilst I think documentation like this is extremely important for users, > > > > this feels like it's documenting how to drive parts of diy and I'm not > > > > convinced that it belongs in the kernel source tree as long as the projects > > > > remain separate. > > > > > > > > Why not contribute this to the herdtools7 documentation, then just reference > > > > that from here? That would also be helpful for other people interested in > > > > memory models, but perhaps not interested in Linux (assuming such people > > > > exist ;). > > > > > > We would still need at least a pointer from the Linux kernel to that > > > documentation, but I am happy either way. We probably need examples of > > > the common cases, but probably not a full exposition of all the available > > > herd7 edges. > > > > Completely agreed. > > > > > Should this be in the herdtools7 documentation, or as added detail > > > from a variation on the "diyone7 -bell linux-kernel.bell -show edges" > > > command? If the latter, I suppose that the ones coming from the .bell > > > file might simply be labelled as such. > > > > Many of the edges aren't specific to the Linux kernel, so I think they > > should be part of the diyone7 documentation. We could then describe only > > the additional edges added by the kernel memory model (e.g. "Once") in > > the kernel documentation. > > And there are a -lot- of them, and they are likely to change going > forward, both in herd7 and in linux-kernel.bell. How about if I give > examples and say where they are from and how to get a list, as in the > following --squash commit to be merged with the orginal? Sure, that looks much easier to maintain. With that, you can add my ack: Acked-by: Will Deacon <will.deacon@xxxxxxx> Cheers, Will > ------------------------------------------------------------------------ > > commit e366b8cd832535894c55265c112355c4de9a3247 > Author: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> > Date: Wed Sep 5 15:38:00 2018 -0700 > > squash! EXP tools/memory-model: Add litmus-test naming scheme > > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> > [ paulmck: Apply feedback from Will Deacon. ] > > diff --git a/tools/memory-model/litmus-tests/README b/tools/memory-model/litmus-tests/README > index 08c1116c0314..5ee08f129094 100644 > --- a/tools/memory-model/litmus-tests/README > +++ b/tools/memory-model/litmus-tests/README > @@ -243,56 +243,11 @@ produce the name: > > Adding the ".litmus" suffix: SB+rfionceonce-poonceonces.litmus > > +The descriptors that describe connections between consecutive accesses > +within the cycle through a given litmus test can be provided by the herd > +tool (Rfi, Po, Fre, and so on) or by the linux-kernel.bell file (Once, > +Release, Acquire, and so on). > > -======================= > -LITMUS TEST DESCRIPTORS > -======================= > - > -These descriptors cover connections between consecutive accesses within > -the cycle through a given litmus test: > - > -Fre: From-read external. The current process wrote a variable that > - the previous process read. Example: The SB (store buffering) test. > -Fri: From-read internal. This process read a variable and then > - immediately wrote to it. Example: ??? > -PodRR: Program-order different variable, read followed by read. > - This process read a variable and again read a different variable. > - Example: The read-side process in the MP (message-passing) test. > -PodRW: Program-order different variable, read followed by write. > - This process read a variable and then wrote a different variable. > - Example: The LB (load buffering) test. > -PodWR: Program-order different variable, write followed by read. > - This process wrote a variable and then read a different variable. > - Example: The SB (store buffering) test. > -PodWW: Program-order different variable, write followed by write. > - This process wrote a variable and again wrote a different variable. > - Example: The write-side process in the MP (message-passing) test. > -PosRR: Program-order same variable, read followed by read. > - This process read a variable and again read that same variable. > - Example: ??? > -PosRW: Program-order same variable, read followed by write. > - This process read a variable and then wrote that same variable. > - Example: ??? > -PosWR: Program-order same variable, write followed by read. > - This process wrote a variable and then read that same variable. > - Example: ??? > -PosWW: Program-order same variable, write followed by write. > - This process wrote a variable and again wrote that same variable. > - Example: ??? > -Rfe: Read-from external. The current process read a variable written > - by the previous process. Example: The MP (message passing) test. > -Rfi: Read-from internal. The current process wrote a variable and then > - immediately read the value back from it. For the purposes > - of litmus-test code generation, Rfi acts identically to PosWR. > - However, they differ for purposes of naming, and they also result > - in different "exists" clauses. > - Example: ??? > -Wse: Write same external. The current process wrote to a variable that > - was also written to by the previous process. Example: ??? > -Wsi: Write same internal. The current process wrote to a variable and > - then immediately wrote to it again. Example: ??? > - > -Please note that the above is a partial list. To see the full list of > -descriptors, execute the following command: > +To see the full list of descriptors, execute the following command: > > $ diyone7 -bell linux-kernel.bell -show edges >
