search for: litmus

On Fri, Jan 15, 2016 at 09:39:12AM -0800, Paul E. McKenney wrote: > Should we start putting litmus tests for the various examples > somewhere, perhaps in a litmus-tests directory within each participating > architecture? I have a pile of powerpc-related litmus tests on my laptop, > but they probably aren't doing all that much good there. Yeah, or a version of them in C that we can...

On Fri, Jan 15, 2016 at 09:39:12AM -0800, Paul E. McKenney wrote: > Should we start putting litmus tests for the various examples > somewhere, perhaps in a litmus-tests directory within each participating > architecture? I have a pile of powerpc-related litmus tests on my laptop, > but they probably aren't doing all that much good there. Yeah, or a version of them in C that we can...

...16 at 10:24:32AM +0000, Will Deacon wrote: > > > > See my earlier reply [1] (but also, your WRC Linux example looks more > > > > like a variant on WWC and I couldn't really follow it). > > > > > > I will revisit my WRC Linux example. And yes, creating litmus tests > > > that use non-fake dependencies is still a bit of an undertaking. :-/ > > > I am sure that it will seem more natural with time and experience... > > > > Hmmm... You are quite right, I did do WWC. I need to change cpu2()'s > > last access from a...

...16 at 10:24:32AM +0000, Will Deacon wrote: > > > > See my earlier reply [1] (but also, your WRC Linux example looks more > > > > like a variant on WWC and I couldn't really follow it). > > > > > > I will revisit my WRC Linux example. And yes, creating litmus tests > > > that use non-fake dependencies is still a bit of an undertaking. :-/ > > > I am sure that it will seem more natural with time and experience... > > > > Hmmm... You are quite right, I did do WWC. I need to change cpu2()'s > > last access from a...

Hello, I started a little pet project of making a webdav plugin for mongrel. First thing I did was get the test suite called litmus from http://www.webdav.org/neon/litmus/ and run it against a completely dummy handler that doesn''t even try to handle anything. Then mongrel said to me: BAD CLIENT (127.0.0.1): Invalid HTTP format, parsing fails. REQUEST DATA: DELETE /test/litmus/frag/#ment HTTP/1.1 Host:...

...; Me, I am wondering what WRC+addr+addr has to do with anything at all. > > > > See my earlier reply [1] (but also, your WRC Linux example looks more > > like a variant on WWC and I couldn't really follow it). > > I will revisit my WRC Linux example. And yes, creating litmus tests > that use non-fake dependencies is still a bit of an undertaking. :-/ > I am sure that it will seem more natural with time and experience... Hmmm... You are quite right, I did do WWC. I need to change cpu2()'s last access from a store to a load to get WRC. Plus the levels of i...

...; Me, I am wondering what WRC+addr+addr has to do with anything at all. > > > > See my earlier reply [1] (but also, your WRC Linux example looks more > > like a variant on WWC and I couldn't really follow it). > > I will revisit my WRC Linux example. And yes, creating litmus tests > that use non-fake dependencies is still a bit of an undertaking. :-/ > I am sure that it will seem more natural with time and experience... Hmmm... You are quite right, I did do WWC. I need to change cpu2()'s last access from a store to a load to get WRC. Plus the levels of i...

Hi all, I'm diagnosing a problem related to PRI card. I would like to know the following: assuming I've got a working PRI card and correctly installed Linux drivers and a PRI line connected to the card, even without starting asterisk, shouldn't I hear a ring tone when I dial the number? I'm getting busy tone all the time. I'm thinking the patch cable I made may be causing

On Thu, Jan 14, 2016 at 01:29:13PM -0800, Paul E. McKenney wrote: > So smp_mb() provides transitivity, as do pairs of smp_store_release() > and smp_read_acquire(), But they provide different grades of transitivity, which is where all the confusion lays. smp_mb() is strongly/globally transitive, all CPUs will agree on the order. Whereas the RCpc release+acquire is weakly so, only the two

On Thu, Jan 14, 2016 at 01:29:13PM -0800, Paul E. McKenney wrote: > So smp_mb() provides transitivity, as do pairs of smp_store_release() > and smp_read_acquire(), But they provide different grades of transitivity, which is where all the confusion lays. smp_mb() is strongly/globally transitive, all CPUs will agree on the order. Whereas the RCpc release+acquire is weakly so, only the two

...e: > > > > > > See my earlier reply [1] (but also, your WRC Linux example looks more > > > > > > like a variant on WWC and I couldn't really follow it). > > > > > > > > > > I will revisit my WRC Linux example. And yes, creating litmus tests > > > > > that use non-fake dependencies is still a bit of an undertaking. :-/ > > > > > I am sure that it will seem more natural with time and experience... > > > > > > > > Hmmm... You are quite right, I did do WWC. I need to change c...

...e: > > > > > > See my earlier reply [1] (but also, your WRC Linux example looks more > > > > > > like a variant on WWC and I couldn't really follow it). > > > > > > > > > > I will revisit my WRC Linux example. And yes, creating litmus tests > > > > > that use non-fake dependencies is still a bit of an undertaking. :-/ > > > > > I am sure that it will seem more natural with time and experience... > > > > > > > > Hmmm... You are quite right, I did do WWC. I need to change c...

...t; > Good point! > > Using grace periods in place of smp_mb() also provides strong/global > transitivity, but also insanely high latencies. ;-) > > The patch below updates Documentation/memory-barriers.txt to define > local vs. global transitivity. The corresponding ppcmem litmus test > is included below as well. > > Should we start putting litmus tests for the various examples > somewhere, perhaps in a litmus-tests directory within each participating > architecture? I have a pile of powerpc-related litmus tests on my laptop, > but they probably aren'...

...t; > Good point! > > Using grace periods in place of smp_mb() also provides strong/global > transitivity, but also insanely high latencies. ;-) > > The patch below updates Documentation/memory-barriers.txt to define > local vs. global transitivity. The corresponding ppcmem litmus test > is included below as well. > > Should we start putting litmus tests for the various examples > somewhere, perhaps in a litmus-tests directory within each participating > architecture? I have a pile of powerpc-related litmus tests on my laptop, > but they probably aren'...

...> interact. > > > > Hoping my memory-barrier.txt patch helps here... > > Yes, that seems a good start. But yesterday you raised the 'fun' point > of two globally ordered sequences connected by a single local link. The conclusion that I am slowly coming to is that litmus tests should not be thought of as linear chains, but rather as cycles. If you think of it as a cycle, then it doesn't matter where the local link is, just how many of them and how they are connected. But I will admit that there are some rather strange litmus tests that challenge this cycle-ce...

...> interact. > > > > Hoping my memory-barrier.txt patch helps here... > > Yes, that seems a good start. But yesterday you raised the 'fun' point > of two globally ordered sequences connected by a single local link. The conclusion that I am slowly coming to is that litmus tests should not be thought of as linear chains, but rather as cycles. If you think of it as a cycle, then it doesn't matter where the local link is, just how many of them and how they are connected. But I will admit that there are some rather strange litmus tests that challenge this cycle-ce...

...> > Using grace periods in place of smp_mb() also provides strong/global > > transitivity, but also insanely high latencies. ;-) > > > > The patch below updates Documentation/memory-barriers.txt to define > > local vs. global transitivity. The corresponding ppcmem litmus test > > is included below as well. > > > > Should we start putting litmus tests for the various examples > > somewhere, perhaps in a litmus-tests directory within each participating > > architecture? I have a pile of powerpc-related litmus tests on my laptop, > &...

...; On Fri, Jan 15, 2016 at 10:24:32AM +0000, Will Deacon wrote: > > > See my earlier reply [1] (but also, your WRC Linux example looks more > > > like a variant on WWC and I couldn't really follow it). > > > > I will revisit my WRC Linux example. And yes, creating litmus tests > > that use non-fake dependencies is still a bit of an undertaking. :-/ > > I am sure that it will seem more natural with time and experience... > > Hmmm... You are quite right, I did do WWC. I need to change cpu2()'s > last access from a store to a load to get W...

...tio specification does not support get/restore > virtqueue state. So we can not use this driver for VM. This can be > addressed by extending the virtio specification. Looks like exactly the kind of hardware limitation VDPA is supposed to paper over within guest. So I suggest we use this as a litmus test, and find ways for VDPA to handle this without spec changes. -- MST

...tio specification does not support get/restore > virtqueue state. So we can not use this driver for VM. This can be > addressed by extending the virtio specification. Looks like exactly the kind of hardware limitation VDPA is supposed to paper over within guest. So I suggest we use this as a litmus test, and find ways for VDPA to handle this without spec changes. -- MST