This patch-set makes part of the mm a lot more preemptible. It converts i_mmap_lock and anon_vma->lock to mutexes and makes mmu_gather fully preemptible. The main motivation was making mm_take_all_locks() preemptible, since it appears people are nesting hundreds of spinlocks there. The side-effects are that can finally make mmu_gather preemptible, something which lots of people have wanted to do for a long time. It also gets us anon_vma refcounting, which seems to result in a nice cleanup of the anon_vma lifetime rules wrt KSM and compaction. This patch-set it build and boot-tested on x86_64 (a previous version was also tested on Dave's Niagra2 machines, and I suppose s390 was too when Martin provided the conversion patch for his arch). There are no known architectures left unconverted. Yanmin ran the -v3 posting through the comprehensive Intel test farm and didn't find any regressions. ( Not included in this posting are the 4 Sparc64 patches that implement gup_fast, those can be applied separately after this series gets anywhere. ) The full series (including the Sparc64 gup_fast bits) also available in -git form from (against Linus' tree as of about an hour ago): git://git.kernel.org/pub/scm/linux/kernel/git/peterz/linux-2.6-mmu_preempt.git mmu_preempt DaveM mentioned some sparc64 trouble with the -v4 posting, this turned out to be a false positive as unpatched kernels also are having trouble on his machines. Linus, Andrew, Stephen, can we add this to -next for .37? -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
