| Message ID | 20210825075620.2607-1-longpeng2@huawei.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | optimize the downtime for vfio migration | expand |
Cc'ing David/Juan for migration big picture (just in case). On 8/25/21 9:56 AM, Longpeng(Mike) wrote: > In vfio migration resume phase, the cost would increase if the > vfio device has more unmasked vectors. We try to optimize it in > this series. > > Patch 1 & 2 are simple code cleanups. > Patch 3 defers to set irqs to vfio core. > Patch 4 & 5 defer to commit the route to KVM core. > > The test VM has 128 vcpus and 8 VF (with 65 vectors enabled), > we mesure the cost of the vfio_msix_enable for each one, and > we can see the total cost can be significantly reduced. > > Origin Apply Patch 3 Apply Patch 3/4/5 > 1st 8 4 2 > 2nd 15 11 2 > 3rd 22 18 2 > 4th 24 25 3 > 5th 36 33 2 > 6th 44 40 3 > 7th 51 47 3 > 8th 58 54 4 > Total 258ms 232ms 21ms > > > Longpeng (Mike) (5): > vfio: use helper to simplfy the failure path in vfio_msi_enable > msix: simplfy the conditional in msix_set/unset_vector_notifiers > vfio: defer to enable msix in migration resume phase > kvm: irqchip: support defer to commit the route > vfio: defer to commit kvm route in migraiton resume phase Overall makes sense and LGTM but migration/KVM are not my area :/
在 2021/8/25 18:05, Philippe Mathieu-Daudé 写道: > Cc'ing David/Juan for migration big picture (just in case). > > On 8/25/21 9:56 AM, Longpeng(Mike) wrote: >> In vfio migration resume phase, the cost would increase if the >> vfio device has more unmasked vectors. We try to optimize it in >> this series. >> >> Patch 1 & 2 are simple code cleanups. >> Patch 3 defers to set irqs to vfio core. >> Patch 4 & 5 defer to commit the route to KVM core. >> >> The test VM has 128 vcpus and 8 VF (with 65 vectors enabled), >> we mesure the cost of the vfio_msix_enable for each one, and >> we can see the total cost can be significantly reduced. >> >> Origin Apply Patch 3 Apply Patch 3/4/5 >> 1st 8 4 2 >> 2nd 15 11 2 >> 3rd 22 18 2 >> 4th 24 25 3 >> 5th 36 33 2 >> 6th 44 40 3 >> 7th 51 47 3 >> 8th 58 54 4 >> Total 258ms 232ms 21ms >> >> >> Longpeng (Mike) (5): >> vfio: use helper to simplfy the failure path in vfio_msi_enable >> msix: simplfy the conditional in msix_set/unset_vector_notifiers >> vfio: defer to enable msix in migration resume phase >> kvm: irqchip: support defer to commit the route >> vfio: defer to commit kvm route in migraiton resume phase > > Overall makes sense and LGTM but migration/KVM are not my area :/ > Thanks all the same :) > . >
Hi maintainers, Ping... 在 2021/8/25 15:56, Longpeng(Mike) 写道: > In vfio migration resume phase, the cost would increase if the > vfio device has more unmasked vectors. We try to optimize it in > this series. > > Patch 1 & 2 are simple code cleanups. > Patch 3 defers to set irqs to vfio core. > Patch 4 & 5 defer to commit the route to KVM core. > > The test VM has 128 vcpus and 8 VF (with 65 vectors enabled), > we mesure the cost of the vfio_msix_enable for each one, and > we can see the total cost can be significantly reduced. > > Origin Apply Patch 3 Apply Patch 3/4/5 > 1st 8 4 2 > 2nd 15 11 2 > 3rd 22 18 2 > 4th 24 25 3 > 5th 36 33 2 > 6th 44 40 3 > 7th 51 47 3 > 8th 58 54 4 > Total 258ms 232ms 21ms > > > Longpeng (Mike) (5): > vfio: use helper to simplfy the failure path in vfio_msi_enable > msix: simplfy the conditional in msix_set/unset_vector_notifiers > vfio: defer to enable msix in migration resume phase > kvm: irqchip: support defer to commit the route > vfio: defer to commit kvm route in migraiton resume phase > > accel/kvm/kvm-all.c | 10 +++-- > accel/stubs/kvm-stub.c | 3 +- > hw/misc/ivshmem.c | 2 +- > hw/pci/msix.c | 7 ++-- > hw/vfio/pci.c | 99 ++++++++++++++++++++++++++++++++++++++------------ > hw/vfio/pci.h | 1 + > hw/virtio/virtio-pci.c | 2 +- > include/sysemu/kvm.h | 4 +- > target/i386/kvm/kvm.c | 2 +- > 9 files changed, 95 insertions(+), 35 deletions(-) >
In vfio migration resume phase, the cost would increase if the vfio device has more unmasked vectors. We try to optimize it in this series. Patch 1 & 2 are simple code cleanups. Patch 3 defers to set irqs to vfio core. Patch 4 & 5 defer to commit the route to KVM core. The test VM has 128 vcpus and 8 VF (with 65 vectors enabled), we mesure the cost of the vfio_msix_enable for each one, and we can see the total cost can be significantly reduced. Origin Apply Patch 3 Apply Patch 3/4/5 1st 8 4 2 2nd 15 11 2 3rd 22 18 2 4th 24 25 3 5th 36 33 2 6th 44 40 3 7th 51 47 3 8th 58 54 4 Total 258ms 232ms 21ms Longpeng (Mike) (5): vfio: use helper to simplfy the failure path in vfio_msi_enable msix: simplfy the conditional in msix_set/unset_vector_notifiers vfio: defer to enable msix in migration resume phase kvm: irqchip: support defer to commit the route vfio: defer to commit kvm route in migraiton resume phase accel/kvm/kvm-all.c | 10 +++-- accel/stubs/kvm-stub.c | 3 +- hw/misc/ivshmem.c | 2 +- hw/pci/msix.c | 7 ++-- hw/vfio/pci.c | 99 ++++++++++++++++++++++++++++++++++++++------------ hw/vfio/pci.h | 1 + hw/virtio/virtio-pci.c | 2 +- include/sysemu/kvm.h | 4 +- target/i386/kvm/kvm.c | 2 +- 9 files changed, 95 insertions(+), 35 deletions(-)