[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH] virtio-net: prevent offloads reset on migration
From: |
Mikhail Sennikovsky |
Subject: |
Re: [PATCH] virtio-net: prevent offloads reset on migration |
Date: |
Thu, 10 Oct 2019 14:15:02 +0200 |
Hi Jason,
Thank you for your reply.
I've submitted the third version of the patch which does the runstate
check as you propose.
Thanks,
Mikhail
Am Do., 10. Okt. 2019 um 07:33 Uhr schrieb Jason Wang <address@hidden>:
>
>
> On 2019/10/2 下午5:55, Dr. David Alan Gilbert wrote:
> > Copying in Stefan, Jason and Michael who know the virtio details
> >
> > Dave
> >
> > * Mikhail Sennikovsky (address@hidden) wrote:
> >> Currently offloads disabled by guest via the
> >> VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET
> >> command are not preserved on VM migration.
> >> Instead all offloads reported by guest features (via
> >> VIRTIO_PCI_GUEST_FEATURES)
> >> get enabled.
> >> What happens is: first the VirtIONet::curr_guest_offloads gets restored
> >> and offloads
> >> are getting set correctly:
> >>
> >> #0 qemu_set_offload (nc=0x555556a11400, csum=1, tso4=0, tso6=0, ecn=0,
> >> ufo=0) at net/net.c:474
> >> #1 virtio_net_apply_guest_offloads (n=0x555557701ca0) at
> >> hw/net/virtio-net.c:720
> >> #2 virtio_net_post_load_device (opaque=0x555557701ca0, version_id=11)
> >> at hw/net/virtio-net.c:2334
> >> #3 vmstate_load_state (f=0x5555569dc010, vmsd=0x555556577c80
> >> <vmstate_virtio_net_device>, opaque=0x555557701ca0, version_id=11)
> >> at migration/vmstate.c:168
> >> #4 virtio_load (vdev=0x555557701ca0, f=0x5555569dc010, version_id=11)
> >> at hw/virtio/virtio.c:2197
> >> #5 virtio_device_get (f=0x5555569dc010, opaque=0x555557701ca0, size=0,
> >> field=0x55555668cd00 <__compound_literal.5>) at hw/virtio/virtio.c:2036
> >> #6 vmstate_load_state (f=0x5555569dc010, vmsd=0x555556577ce0
> >> <vmstate_virtio_net>, opaque=0x555557701ca0, version_id=11) at
> >> migration/vmstate.c:143
> >> #7 vmstate_load (f=0x5555569dc010, se=0x5555578189e0) at
> >> migration/savevm.c:829
> >> #8 qemu_loadvm_section_start_full (f=0x5555569dc010,
> >> mis=0x5555569eee20) at migration/savevm.c:2211
> >> #9 qemu_loadvm_state_main (f=0x5555569dc010, mis=0x5555569eee20) at
> >> migration/savevm.c:2395
> >> #10 qemu_loadvm_state (f=0x5555569dc010) at migration/savevm.c:2467
> >> #11 process_incoming_migration_co (opaque=0x0) at
> >> migration/migration.c:449
> >>
> >> However later on the features are getting restored, and offloads get reset
> >> to
> >> everything supported by features:
> >>
> >> #0 qemu_set_offload (nc=0x555556a11400, csum=1, tso4=1, tso6=1, ecn=0,
> >> ufo=0) at net/net.c:474
> >> #1 virtio_net_apply_guest_offloads (n=0x555557701ca0) at
> >> hw/net/virtio-net.c:720
> >> #2 virtio_net_set_features (vdev=0x555557701ca0, features=5104441767)
> >> at hw/net/virtio-net.c:773
> >> #3 virtio_set_features_nocheck (vdev=0x555557701ca0, val=5104441767) at
> >> hw/virtio/virtio.c:2052
> >> #4 virtio_load (vdev=0x555557701ca0, f=0x5555569dc010, version_id=11)
> >> at hw/virtio/virtio.c:2220
> >> #5 virtio_device_get (f=0x5555569dc010, opaque=0x555557701ca0, size=0,
> >> field=0x55555668cd00 <__compound_literal.5>) at hw/virtio/virtio.c:2036
> >> #6 vmstate_load_state (f=0x5555569dc010, vmsd=0x555556577ce0
> >> <vmstate_virtio_net>, opaque=0x555557701ca0, version_id=11) at
> >> migration/vmstate.c:143
> >> #7 vmstate_load (f=0x5555569dc010, se=0x5555578189e0) at
> >> migration/savevm.c:829
> >> #8 qemu_loadvm_section_start_full (f=0x5555569dc010,
> >> mis=0x5555569eee20) at migration/savevm.c:2211
> >> #9 qemu_loadvm_state_main (f=0x5555569dc010, mis=0x5555569eee20) at
> >> migration/savevm.c:2395
> >> #10 qemu_loadvm_state (f=0x5555569dc010) at migration/savevm.c:2467
> >> #11 process_incoming_migration_co (opaque=0x0) at
> >> migration/migration.c:449
> >>
> >> This patch fixes this by adding an extra argument to the set_features
> >> callback,
> >> specifying whether the offloads are to be reset, and setting it to false
> >> for the migration case.
> >>
> >> Signed-off-by: Mikhail Sennikovsky <address@hidden>
> >> ---
> >> hw/display/virtio-gpu-base.c | 3 ++-
> >> hw/net/virtio-net.c | 5 +++--
> >> hw/virtio/virtio.c | 10 +++++-----
> >> include/hw/virtio/virtio.h | 2 +-
> >> 4 files changed, 11 insertions(+), 9 deletions(-)
> >>
> >> diff --git a/hw/display/virtio-gpu-base.c b/hw/display/virtio-gpu-base.c
> >> index 55e0799..04d8a23 100644
> >> --- a/hw/display/virtio-gpu-base.c
> >> +++ b/hw/display/virtio-gpu-base.c
> >> @@ -193,7 +193,8 @@ virtio_gpu_base_get_features(VirtIODevice *vdev,
> >> uint64_t features,
> >> }
> >>
> >> static void
> >> -virtio_gpu_base_set_features(VirtIODevice *vdev, uint64_t features)
> >> +virtio_gpu_base_set_features(VirtIODevice *vdev, uint64_t features,
> >> + bool reset_offloads)
>
>
> It's not good for e.g gpu to know anything about net.
>
> How about checking runstate and do not call apply_guest_offload() in
> virtio_net_set_features() when in the state of migration?
>
> Thanks
>
>
> >> {
> >> static const uint32_t virgl = (1 << VIRTIO_GPU_F_VIRGL);
> >> VirtIOGPUBase *g = VIRTIO_GPU_BASE(vdev);
> >> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> >> index b9e1cd7..5d108e5 100644
> >> --- a/hw/net/virtio-net.c
> >> +++ b/hw/net/virtio-net.c
> >> @@ -743,7 +743,8 @@ static inline uint64_t
> >> virtio_net_supported_guest_offloads(VirtIONet *n)
> >> return virtio_net_guest_offloads_by_features(vdev->guest_features);
> >> }
> >>
> >> -static void virtio_net_set_features(VirtIODevice *vdev, uint64_t features)
> >> +static void virtio_net_set_features(VirtIODevice *vdev, uint64_t features,
> >> + bool reset_offloads)
> >> {
> >> VirtIONet *n = VIRTIO_NET(vdev);
> >> int i;
> >> @@ -767,7 +768,7 @@ static void virtio_net_set_features(VirtIODevice
> >> *vdev, uint64_t features)
> >> n->rsc6_enabled = virtio_has_feature(features, VIRTIO_NET_F_RSC_EXT)
> >> &&
> >> virtio_has_feature(features, VIRTIO_NET_F_GUEST_TSO6);
> >>
> >> - if (n->has_vnet_hdr) {
> >> + if (reset_offloads && n->has_vnet_hdr) {
> >> n->curr_guest_offloads =
> >> virtio_net_guest_offloads_by_features(features);
> >> virtio_net_apply_guest_offloads(n);
> >> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> >> index a94ea18..b89f7b0 100644
> >> --- a/hw/virtio/virtio.c
> >> +++ b/hw/virtio/virtio.c
> >> @@ -2042,14 +2042,14 @@ const VMStateInfo virtio_vmstate_info = {
> >> .put = virtio_device_put,
> >> };
> >>
> >> -static int virtio_set_features_nocheck(VirtIODevice *vdev, uint64_t val)
> >> +static int virtio_set_features_nocheck(VirtIODevice *vdev, uint64_t val,
> >> bool reset_offloads)
> >> {
> >> VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
> >> bool bad = (val & ~(vdev->host_features)) != 0;
> >>
> >> val &= vdev->host_features;
> >> if (k->set_features) {
> >> - k->set_features(vdev, val);
> >> + k->set_features(vdev, val, reset_offloads);
> >> }
> >> vdev->guest_features = val;
> >> return bad ? -1 : 0;
> >> @@ -2065,7 +2065,7 @@ int virtio_set_features(VirtIODevice *vdev, uint64_t
> >> val)
> >> if (vdev->status & VIRTIO_CONFIG_S_FEATURES_OK) {
> >> return -EINVAL;
> >> }
> >> - ret = virtio_set_features_nocheck(vdev, val);
> >> + ret = virtio_set_features_nocheck(vdev, val, true);
> >> if (!ret) {
> >> if (virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX)) {
> >> /* VIRTIO_RING_F_EVENT_IDX changes the size of the caches.
> >> */
> >> @@ -2217,14 +2217,14 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f,
> >> int version_id)
> >> * host_features.
> >> */
> >> uint64_t features64 = vdev->guest_features;
> >> - if (virtio_set_features_nocheck(vdev, features64) < 0) {
> >> + if (virtio_set_features_nocheck(vdev, features64, false) < 0) {
> >> error_report("Features 0x%" PRIx64 " unsupported. "
> >> "Allowed features: 0x%" PRIx64,
> >> features64, vdev->host_features);
> >> return -1;
> >> }
> >> } else {
> >> - if (virtio_set_features_nocheck(vdev, features) < 0) {
> >> + if (virtio_set_features_nocheck(vdev, features, false) < 0) {
> >> error_report("Features 0x%x unsupported. "
> >> "Allowed features: 0x%" PRIx64,
> >> features, vdev->host_features);
> >> diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
> >> index b189788..fd8cac5 100644
> >> --- a/include/hw/virtio/virtio.h
> >> +++ b/include/hw/virtio/virtio.h
> >> @@ -128,7 +128,7 @@ typedef struct VirtioDeviceClass {
> >> uint64_t requested_features,
> >> Error **errp);
> >> uint64_t (*bad_features)(VirtIODevice *vdev);
> >> - void (*set_features)(VirtIODevice *vdev, uint64_t val);
> >> + void (*set_features)(VirtIODevice *vdev, uint64_t val, bool
> >> reset_offloads);
> >> int (*validate_features)(VirtIODevice *vdev);
> >> void (*get_config)(VirtIODevice *vdev, uint8_t *config);
> >> void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
> >> --
> >> 2.7.4
> >>
> >>
> > --
> > Dr. David Alan Gilbert / address@hidden / Manchester, UK