Avi Kivity wrote: > On 07/01/2010 04:11 AM, Xiao Guangrong wrote: >> >> Marcelo Tosatti wrote: >> >> >>>> + >>>> + addr = gfn_to_hva_many(vcpu->kvm, gfn,&entry); >>>> + if (kvm_is_error_hva(addr)) >>>> + return -1; >>>> + >>>> + entry = min(entry, (int)(end - start)); >>>> + ret = __get_user_pages_fast(addr, entry, 1, pages); >>>> + if (ret<= 0) >>>> + return -1; >>>> >>> Why can't you use gfn_to_pfn_atomic() here, one page at a time? Is >>> the overhead significant that this is worthwhile? >>> >>> You're bypassing the centralized interface. >>> >> I think it's worthwhile to do since we can reduce gup overhead, no reason >> to traverse process's page table again and again for the consecutive >> pages. >> > > Then we should make the centralized interface work in terms of multiple > pages, and write the single-page interfaces in terms of the multipage > interfaces. > Umm, i'll import a new function named gfn_to_pfn_many_atomic(... int *enough), using 'enough' to indicate whether have got the all consecutive pages in the slot, Marcelo, how about it? :-) -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
