yes, i patch qemu as well. and i found the address of second vf is not in mmio range. the first one is fine. 2010/12/1 Yang, Sheng <sheng.yang@xxxxxxxxx>: > On Wednesday 01 December 2010 16:41:38 lidong chen wrote: >> I used sr-iov, give each vm 2 vf. >> after apply the patch, and i found performence is the same. >> >> the reason is in function msix_mmio_write, mostly addr is not in mmio >> range. > > Did you patch qemu as well? You can see it's impossible for kernel part to work > alone... > > http://www.mail-archive.com/kvm@xxxxxxxxxxxxxxx/msg44368.html > > -- > regards > Yang, Sheng > > >> >> static int msix_mmio_write(struct kvm_io_device *this, gpa_t addr, int len, >> const void *val) >> { >> struct kvm_assigned_dev_kernel *adev = >> container_of(this, struct kvm_assigned_dev_kernel, >> msix_mmio_dev); >> int idx, r = 0; >> unsigned long new_val = *(unsigned long *)val; >> >> mutex_lock(&adev->kvm->lock); >> if (!msix_mmio_in_range(adev, addr, len)) { >> // return here. >> r = -EOPNOTSUPP; >> goto out; >> } >> >> i printk the value: >> addr start end len >> F004C00C F0044000 F0044030 4 >> >> 00:06.0 Ethernet controller: Intel Corporation Unknown device 10ed (rev 01) >> Subsystem: Intel Corporation Unknown device 000c >> Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- >> Stepping- SERR- FastB2B- >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- >> <TAbort- <MAbort- >SERR- <PERR- >> Latency: 0 >> Region 0: Memory at f0040000 (32-bit, non-prefetchable) [size=16K] >> Region 3: Memory at f0044000 (32-bit, non-prefetchable) [size=16K] >> Capabilities: [40] MSI-X: Enable+ Mask- TabSize=3 >> Vector table: BAR=3 offset=00000000 >> PBA: BAR=3 offset=00002000 >> >> 00:07.0 Ethernet controller: Intel Corporation Unknown device 10ed (rev 01) >> Subsystem: Intel Corporation Unknown device 000c >> Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- >> Stepping- SERR- FastB2B- >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- >> <TAbort- <MAbort- >SERR- <PERR- >> Latency: 0 >> Region 0: Memory at f0048000 (32-bit, non-prefetchable) [size=16K] >> Region 3: Memory at f004c000 (32-bit, non-prefetchable) [size=16K] >> Capabilities: [40] MSI-X: Enable+ Mask- TabSize=3 >> Vector table: BAR=3 offset=00000000 >> PBA: BAR=3 offset=00002000 >> >> >> >> +static bool msix_mmio_in_range(struct kvm_assigned_dev_kernel *adev, >> + gpa_t addr, int len) >> +{ >> + gpa_t start, end; >> + >> + BUG_ON(adev->msix_mmio_base == 0); >> + start = adev->msix_mmio_base; >> + end = adev->msix_mmio_base + PCI_MSIX_ENTRY_SIZE * >> + adev->msix_max_entries_nr; >> + if (addr >= start && addr + len <= end) >> + return true; >> + >> + return false; >> +} >> >> 2010/11/30 Yang, Sheng <sheng.yang@xxxxxxxxx>: >> > On Tuesday 30 November 2010 17:10:11 lidong chen wrote: >> >> sr-iov also meet this problem, MSIX mask waste a lot of cpu resource. >> >> >> >> I test kvm with sriov, which the vf driver could not disable msix. >> >> so the host os waste a lot of cpu. cpu rate of host os is 90%. >> >> >> >> then I test xen with sriov, there ara also a lot of vm exits caused by >> >> MSIX mask. >> >> but the cpu rate of xen and domain0 is less than kvm. cpu rate of xen >> >> and domain0 is 60%. >> >> >> >> without sr-iov, the cpu rate of xen and domain0 is higher than kvm. >> >> >> >> so i think the problem is kvm waste more cpu resource to deal with MSIX >> >> mask. and we can see how xen deal with MSIX mask. >> >> >> >> if this problem sloved, maybe with MSIX enabled, the performace is >> >> better. >> > >> > Please refer to my posted patches for this issue. >> > >> > http://www.spinics.net/lists/kvm/msg44992.html >> > >> > -- >> > regards >> > Yang, Sheng >> > >> >> 2010/11/23 Avi Kivity <avi@xxxxxxxxxx>: >> >> > On 11/23/2010 09:27 AM, lidong chen wrote: >> >> >> can you tell me something about this problem. >> >> >> thanks. >> >> > >> >> > Which problem? >> >> > >> >> > -- >> >> > I have a truly marvellous patch that fixes the bug which this >> >> > signature is too narrow to contain. > -- 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
