2017-11-06 18:10 GMT+08:00 Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>: > Wanpeng Li <kernellwp@xxxxxxxxx> writes: > >> 2017-11-06 17:14 GMT+08:00 Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>: >>> Wanpeng Li <kernellwp@xxxxxxxxx> writes: >>> >>>> 2017-08-03 0:09 GMT+08:00 Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>: >>>>> Changes since v9: >>>>> - Rebase to 4.13-rc3. >>>>> - Drop PATCH1 as it was already taken by Greg to char-misc tree. There're no >>>>> functional dependencies on this patch so the series can go through a different tree >>>>> (and it actually belongs to x86 if I got Ingo's comment right). >>>>> - Add in missing void return type in PATCH1 [Colin King, Ingo Molnar, Greg KH] >>>>> - A few minor fixes in what is now PATCH7: add pr_fmt, tiny style fix in >>>>> hyperv_flush_tlb_others() [Andy Shevchenko] >>>>> - Fix "error: implicit declaration of function 'virt_to_phys'" in PATCH2 >>>>> reported by kbuild test robot (#include <asm/io.h>) >>>>> - Add Steven's 'Reviewed-by:' to PATCH9. >>>>> >>>>> Original description: >>>>> >>>>> Hyper-V supports hypercalls for doing local and remote TLB flushing and >>>>> gives its guests hints when using hypercall is preferred. While doing >>>>> hypercalls for local TLB flushes is probably not practical (and is not >>>>> being suggested by modern Hyper-V versions) remote TLB flush with a >>>>> hypercall brings significant improvement. >>>>> >>>>> To test the series I wrote a special 'TLB trasher': on a 16 vCPU guest I >>>>> was creating 32 threads which were doing 100000 mmap/munmaps each on some >>>>> big file. Here are the results: >>>>> >>>>> Before: >>>>> # time ./pthread_mmap ./randfile >>>>> real 3m33.118s >>>>> user 0m3.698s >>>>> sys 3m16.624s >>>>> >>>>> After: >>>>> # time ./pthread_mmap ./randfile >>>>> real 2m19.920s >>>>> user 0m2.662s >>>>> sys 2m9.948s >>>>> >>>>> This series brings a number of small improvements along the way: fast >>>>> hypercall implementation and using it for event signaling, rep hypercalls >>>>> implementation, hyperv tracing subsystem (which only traces the newly added >>>>> remote TLB flush for now). >>>>> >>>> >>>> Hi Vitaly, >>>> >>>> Could you attach your benchmark? I'm interested in to try the >>>> implementation in paravirt kvm. >>>> >>> >>> Oh, this would be cool) I briefly discussed the idea with Radim (one of >>> KVM maintainers) during the last KVM Forum and he wasn't opposed to the >>> idea. Need to talk to Paolo too. Good thing is that we have everything >> >> I talk with Paolo today and he points this feature to me, so I believe >> he likes it. :) In addition, >> https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs >> I search Hypervisor Top Level Functional Specification v5.0b.pdf >> document but didn't find a section introduce the Hyper-V: >> paravirtualized remote TLB flushing and hypercall stuff, could you >> point out? >> > > It's there, search for > HvFlushVirtualAddressSpace/HvFlushVirtualAddressSpaceEx and > HvFlushVirtualAddressList/HvFlushVirtualAddressListEx. Got it, thanks. Regards, Wanpeng Li _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
