On Thu, 2013-11-07 at 14:43 -0800, Michel Lespinasse wrote: > On Thu, Nov 7, 2013 at 2:21 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > > On Thu, Nov 07, 2013 at 01:15:51PM -0800, Tim Chen wrote: > >> Michel, are you planning to do an implementation of > >> load-acquire/store-release functions of various architectures? > > > > A little something like this: > > http://marc.info/?l=linux-arch&m=138386254111507 > > > > It so happens we were working on that the past week or so due to another > > issue ;-) > > Haha, awesome, I wasn't aware of this effort. > > Tim: my approach would be to provide the acquire/release operations in > arch-specific include files, and have a default implementation using > barriers for arches who don't provide these new ops. That way you make > it work on all arches at once (using the default implementation) and > make it fast on any arch that cares. > > >> Or is the approach of arch specific memory barrier for MCS > >> an acceptable one before load-acquire and store-release > >> are available? Are there any technical issues remaining with > >> the patchset after including including Waiman's arch specific barrier? > > I don't want to stand in the way of Waiman's change, and I had > actually taken the same approach with arch-specific barriers when > proposing some queue spinlocks in the past; however I do feel that > this comes back regularly enough that having acquire/release > primitives available would help, hence my proposal. > > That said, earlier in the thread Linus said we should probably get all > our ducks in a row before going forward with this, so... > With the load_acquire and store_release implemented, it should be pretty straightforward to implement MCS with them. I'll respin the patch series with these primitives. Thanks. Tim -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>