Andrea Arcangeli wrote: > On Wed, Apr 02, 2008 at 02:16:41PM +0300, Avi Kivity wrote: > >> Ugh, there's still mark_page_accessed() and SetPageDirty(). >> > > btw, like PG_dirty is only set if the spte is writeable, > mark_page_accessed should only run if the accessed bit is set in the > spte. It doesn't matter now as nobody could possibly clear it,
No one will clear it now, but it can start out cleared. This is done on speculative mmu_set_spte(): when the guest writes into its page tables, we update the spte speculatively, but the guest may not actually access that location (for example, due to a page fault clustering). So the change makes sense even now. > It still skips an atomic op. Your plan still sounds just fine despite > the above, infact it sounds too perfect: the awk hack to re-add the > refcounting when building the external module if CONFIG_MMU_NOTIFIER > isn't defined is going to be messy, a plain CONFIG_MMU_NOTIFIER in > kvm.git would be simpler and more robust IMHO even if less perfect :). > Worst case, we stick a get_user_pages() inside the memslot setup function. That makes things not swappable for pre-mmu notifiers, but completely safe. I'd rather avoid special casing the core code, whenever possible. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
