From: Jérôme Glisse <jgli...@redhat.com> (Andrew you already have v1 in your queue of patch 1, patch 2 is new, i think you can drop it patch 1 v1 for v2, v2 is bit more conservative and i fixed typos)
All this only affect user of invalidate_range callback (at this time CAPI arch/powerpc/platforms/powernv/npu-dma.c, IOMMU ATS/PASID in drivers/iommu/amd_iommu_v2.c|intel-svm.c) This patchset remove useless double call to mmu_notifier->invalidate_range callback wherever it is safe to do so. The first patch just remove useless call and add documentation explaining why it is safe to do so. The second patch go further by introducing mmu_notifier_invalidate_range_only_end() which skip callback to invalidate_range this can be done when clearing a pte, pmd or pud with notification which call invalidate_range right after clearing under the page table lock. It should improve performances but i am lacking hardware and benchmarks which might show an improvement. Maybe folks in cc can help here. Cc: Andrea Arcangeli <aarca...@redhat.com> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Joerg Roedel <jroe...@suse.de> Cc: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com> Cc: David Woodhouse <dw...@infradead.org> Cc: Alistair Popple <alist...@popple.id.au> Cc: Michael Ellerman <m...@ellerman.id.au> Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org> Cc: Stephen Rothwell <s...@canb.auug.org.au> Cc: Andrew Donnellan <andrew.donnel...@au1.ibm.com> Cc: io...@lists.linux-foundation.org Cc: linuxppc-...@lists.ozlabs.org Jérôme Glisse (2): mm/mmu_notifier: avoid double notification when it is useless v2 mm/mmu_notifier: avoid call to invalidate_range() in range_end() Documentation/vm/mmu_notifier.txt | 93 +++++++++++++++++++++++++++++++++++++++ fs/dax.c | 9 +++- include/linux/mmu_notifier.h | 20 +++++++-- mm/huge_memory.c | 66 ++++++++++++++++++++++++--- mm/hugetlb.c | 16 +++++-- mm/ksm.c | 15 ++++++- mm/memory.c | 6 ++- mm/migrate.c | 15 +++++-- mm/mmu_notifier.c | 11 ++++- mm/rmap.c | 59 ++++++++++++++++++++++--- 10 files changed, 281 insertions(+), 29 deletions(-) create mode 100644 Documentation/vm/mmu_notifier.txt -- 2.13.6
