Hi, Ralph, On Fri, 2019-04-12 at 11:52 -0700, Ralph Campbell wrote: > On 4/12/19 9:04 AM, Thomas Hellstrom wrote: > > Add two utilities to a) write-protect and b) clean all ptes > > pointing into > > a range of an address space > > A period at the end, please. > > > The utilities are intended to aid in tracking dirty pages (either > > driver-allocated system memory or pci device memory). > > The write-protect utility should be used in conjunction with > > page_mkwrite() and pfn_mkwrite() to trigger write page-faults on > > page > > accesses. Typically one would want to use this on sparse accesses > > into > > large memory regions. The clean utility should be used to utilize > > hardware dirtying functionality and avoid the overhead of page- > > faults, > > typically on large accesses into small memory regions. > > > > The added file "apply_as_range.c" is initially listed as maintained > > by > > VMware under our DRM driver. If somebody would like it elsewhere, > > that's of course no problem. > > > > Notable changes since RFC: > > - Added comments to help avoid the usage of these function for VMAs > > it's not intended for. We also do advisory checks on the > > vm_flags and > > warn on illegal usage. > > - Perform the pte modifications the same way softdirty does. > > - Add mmu_notifier range invalidation calls. > > - Add a config option so that this code is not unconditionally > > included. > > - Tell the mmu_gather code about pending tlb flushes. > > > > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> > > Cc: Will Deacon <will.deacon@xxxxxxx> > > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > > Cc: Rik van Riel <riel@xxxxxxxxxxx> > > Cc: Minchan Kim <minchan@xxxxxxxxxx> > > Cc: Michal Hocko <mhocko@xxxxxxxx> > > Cc: Huang Ying <ying.huang@xxxxxxxxx> > > Cc: Souptick Joarder <jrdr.linux@xxxxxxxxx> > > Cc: "Jérôme Glisse" <jglisse@xxxxxxxxxx> > > Cc: linux-mm@xxxxxxxxx > > Cc: linux-kernel@xxxxxxxxxxxxxxx > > Signed-off-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx> > > Reviewed-by: Ralph Campbell <rcampbell@xxxxxxxxxx> Thanks for reviewing the patches. I'll incorporate your suggestions in v2.
