| Message ID | 20250307-rss-v9-6-df76624025eb@daynix.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | tun: Introduce virtio-net hashing feature | expand |
On Fri, Mar 7, 2025 at 7:02 PM Akihiko Odaki <akihiko.odaki@daynix.com> wrote: > > VIRTIO_NET_F_HASH_REPORT allows to report hash values calculated on the > host. When VHOST_NET_F_VIRTIO_NET_HDR is employed, it will report no > hash values (i.e., the hash_report member is always set to > VIRTIO_NET_HASH_REPORT_NONE). Otherwise, the values reported by the > underlying socket will be reported. > > VIRTIO_NET_F_HASH_REPORT requires VIRTIO_F_VERSION_1. > > Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com> > Tested-by: Lei Yang <leiyang@redhat.com> > --- > drivers/vhost/net.c | 49 +++++++++++++++++++++++++++++-------------------- > 1 file changed, 29 insertions(+), 20 deletions(-) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index b9b9e9d40951856d881d77ac74331d914473cd56..16b241b44f89820a42c302f3586ea6bb5e0d4289 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -73,6 +73,7 @@ enum { > VHOST_NET_FEATURES = VHOST_FEATURES | > (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | > (1ULL << VIRTIO_NET_F_MRG_RXBUF) | > + (1ULL << VIRTIO_NET_F_HASH_REPORT) | > (1ULL << VIRTIO_F_ACCESS_PLATFORM) | > (1ULL << VIRTIO_F_RING_RESET) > }; > @@ -1097,9 +1098,11 @@ static void handle_rx(struct vhost_net *net) > .msg_controllen = 0, > .msg_flags = MSG_DONTWAIT, > }; > - struct virtio_net_hdr hdr = { > - .flags = 0, > - .gso_type = VIRTIO_NET_HDR_GSO_NONE > + struct virtio_net_hdr_v1_hash hdr = { > + .hdr = { > + .flags = 0, > + .gso_type = VIRTIO_NET_HDR_GSO_NONE > + } > }; > size_t total_len = 0; > int err, mergeable; > @@ -1110,7 +1113,6 @@ static void handle_rx(struct vhost_net *net) > bool set_num_buffers; > struct socket *sock; > struct iov_iter fixup; > - __virtio16 num_buffers; > int recv_pkts = 0; > > mutex_lock_nested(&vq->mutex, VHOST_NET_VQ_RX); > @@ -1191,30 +1193,30 @@ static void handle_rx(struct vhost_net *net) > vhost_discard_vq_desc(vq, headcount); > continue; > } > + hdr.hdr.num_buffers = cpu_to_vhost16(vq, headcount); > /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ > if (unlikely(vhost_hlen)) { > - if (copy_to_iter(&hdr, sizeof(hdr), > - &fixup) != sizeof(hdr)) { > + if (copy_to_iter(&hdr, vhost_hlen, > + &fixup) != vhost_hlen) { > vq_err(vq, "Unable to write vnet_hdr " > "at addr %p\n", vq->iov->iov_base); > goto out; Is this an "issue" specific to RSS/HASH? If it's not, we need a separate patch. Honestly, I'm not sure if it's too late to fix this. Others look fine. Thanks
On 2025/03/10 13:43, Jason Wang wrote: > On Fri, Mar 7, 2025 at 7:02 PM Akihiko Odaki <akihiko.odaki@daynix.com> wrote: >> >> VIRTIO_NET_F_HASH_REPORT allows to report hash values calculated on the >> host. When VHOST_NET_F_VIRTIO_NET_HDR is employed, it will report no >> hash values (i.e., the hash_report member is always set to >> VIRTIO_NET_HASH_REPORT_NONE). Otherwise, the values reported by the >> underlying socket will be reported. >> >> VIRTIO_NET_F_HASH_REPORT requires VIRTIO_F_VERSION_1. >> >> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com> >> Tested-by: Lei Yang <leiyang@redhat.com> >> --- >> drivers/vhost/net.c | 49 +++++++++++++++++++++++++++++-------------------- >> 1 file changed, 29 insertions(+), 20 deletions(-) >> >> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c >> index b9b9e9d40951856d881d77ac74331d914473cd56..16b241b44f89820a42c302f3586ea6bb5e0d4289 100644 >> --- a/drivers/vhost/net.c >> +++ b/drivers/vhost/net.c >> @@ -73,6 +73,7 @@ enum { >> VHOST_NET_FEATURES = VHOST_FEATURES | >> (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | >> (1ULL << VIRTIO_NET_F_MRG_RXBUF) | >> + (1ULL << VIRTIO_NET_F_HASH_REPORT) | >> (1ULL << VIRTIO_F_ACCESS_PLATFORM) | >> (1ULL << VIRTIO_F_RING_RESET) >> }; >> @@ -1097,9 +1098,11 @@ static void handle_rx(struct vhost_net *net) >> .msg_controllen = 0, >> .msg_flags = MSG_DONTWAIT, >> }; >> - struct virtio_net_hdr hdr = { >> - .flags = 0, >> - .gso_type = VIRTIO_NET_HDR_GSO_NONE >> + struct virtio_net_hdr_v1_hash hdr = { >> + .hdr = { >> + .flags = 0, >> + .gso_type = VIRTIO_NET_HDR_GSO_NONE >> + } >> }; >> size_t total_len = 0; >> int err, mergeable; >> @@ -1110,7 +1113,6 @@ static void handle_rx(struct vhost_net *net) >> bool set_num_buffers; >> struct socket *sock; >> struct iov_iter fixup; >> - __virtio16 num_buffers; >> int recv_pkts = 0; >> >> mutex_lock_nested(&vq->mutex, VHOST_NET_VQ_RX); >> @@ -1191,30 +1193,30 @@ static void handle_rx(struct vhost_net *net) >> vhost_discard_vq_desc(vq, headcount); >> continue; >> } >> + hdr.hdr.num_buffers = cpu_to_vhost16(vq, headcount); >> /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ >> if (unlikely(vhost_hlen)) { >> - if (copy_to_iter(&hdr, sizeof(hdr), >> - &fixup) != sizeof(hdr)) { >> + if (copy_to_iter(&hdr, vhost_hlen, >> + &fixup) != vhost_hlen) { >> vq_err(vq, "Unable to write vnet_hdr " >> "at addr %p\n", vq->iov->iov_base); >> goto out; > > Is this an "issue" specific to RSS/HASH? If it's not, we need a separate patch. > > Honestly, I'm not sure if it's too late to fix this. There is nothing wrong with the current implementation. The current implementation fills the header with zero except num_buffers, which it fills some real value. This functionality is working fine with VIRTIO_NET_F_MRG_RXBUF and VIRTIO_F_VERSION_1, which change the header size. Now I'm adding VIRTIO_NET_F_HASH_REPORT and it adds the hash_report field, which also needs to be initialized with zero, so I'm making sure vhost_net will also initialize it. Regards, Akihiko Odaki > > Others look fine. > > Thanks >
On Mon, Mar 10, 2025 at 3:04 PM Akihiko Odaki <akihiko.odaki@daynix.com> wrote: > > On 2025/03/10 13:43, Jason Wang wrote: > > On Fri, Mar 7, 2025 at 7:02 PM Akihiko Odaki <akihiko.odaki@daynix.com> wrote: > >> > >> VIRTIO_NET_F_HASH_REPORT allows to report hash values calculated on the > >> host. When VHOST_NET_F_VIRTIO_NET_HDR is employed, it will report no > >> hash values (i.e., the hash_report member is always set to > >> VIRTIO_NET_HASH_REPORT_NONE). Otherwise, the values reported by the > >> underlying socket will be reported. > >> > >> VIRTIO_NET_F_HASH_REPORT requires VIRTIO_F_VERSION_1. > >> > >> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com> > >> Tested-by: Lei Yang <leiyang@redhat.com> > >> --- > >> drivers/vhost/net.c | 49 +++++++++++++++++++++++++++++-------------------- > >> 1 file changed, 29 insertions(+), 20 deletions(-) > >> > >> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > >> index b9b9e9d40951856d881d77ac74331d914473cd56..16b241b44f89820a42c302f3586ea6bb5e0d4289 100644 > >> --- a/drivers/vhost/net.c > >> +++ b/drivers/vhost/net.c > >> @@ -73,6 +73,7 @@ enum { > >> VHOST_NET_FEATURES = VHOST_FEATURES | > >> (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | > >> (1ULL << VIRTIO_NET_F_MRG_RXBUF) | > >> + (1ULL << VIRTIO_NET_F_HASH_REPORT) | > >> (1ULL << VIRTIO_F_ACCESS_PLATFORM) | > >> (1ULL << VIRTIO_F_RING_RESET) > >> }; > >> @@ -1097,9 +1098,11 @@ static void handle_rx(struct vhost_net *net) > >> .msg_controllen = 0, > >> .msg_flags = MSG_DONTWAIT, > >> }; > >> - struct virtio_net_hdr hdr = { > >> - .flags = 0, > >> - .gso_type = VIRTIO_NET_HDR_GSO_NONE > >> + struct virtio_net_hdr_v1_hash hdr = { > >> + .hdr = { > >> + .flags = 0, > >> + .gso_type = VIRTIO_NET_HDR_GSO_NONE > >> + } > >> }; > >> size_t total_len = 0; > >> int err, mergeable; > >> @@ -1110,7 +1113,6 @@ static void handle_rx(struct vhost_net *net) > >> bool set_num_buffers; > >> struct socket *sock; > >> struct iov_iter fixup; > >> - __virtio16 num_buffers; > >> int recv_pkts = 0; > >> > >> mutex_lock_nested(&vq->mutex, VHOST_NET_VQ_RX); > >> @@ -1191,30 +1193,30 @@ static void handle_rx(struct vhost_net *net) > >> vhost_discard_vq_desc(vq, headcount); > >> continue; > >> } > >> + hdr.hdr.num_buffers = cpu_to_vhost16(vq, headcount); > >> /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ > >> if (unlikely(vhost_hlen)) { > >> - if (copy_to_iter(&hdr, sizeof(hdr), > >> - &fixup) != sizeof(hdr)) { > >> + if (copy_to_iter(&hdr, vhost_hlen, > >> + &fixup) != vhost_hlen) { > >> vq_err(vq, "Unable to write vnet_hdr " > >> "at addr %p\n", vq->iov->iov_base); > >> goto out; > > > > Is this an "issue" specific to RSS/HASH? If it's not, we need a separate patch. > > > > Honestly, I'm not sure if it's too late to fix this. > > There is nothing wrong with the current implementation. Note that I meant the vhost_hlen part, and the current code is tricky. The comment said: """ /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ """ So it tries to only offer virtio_net_hdr even if vhost_hlen is the set to mrg_rxbuf len. And this patch changes this behaviour. Thanks > The current > implementation fills the header with zero except num_buffers, which it > fills some real value. This functionality is working fine with > VIRTIO_NET_F_MRG_RXBUF and VIRTIO_F_VERSION_1, which change the header size. > > Now I'm adding VIRTIO_NET_F_HASH_REPORT and it adds the hash_report > field, which also needs to be initialized with zero, so I'm making sure > vhost_net will also initialize it. > > Regards, > Akihiko Odaki > > > > > Others look fine. > > > > Thanks > > >
On 2025/03/11 9:42, Jason Wang wrote: > On Mon, Mar 10, 2025 at 3:04 PM Akihiko Odaki <akihiko.odaki@daynix.com> wrote: >> >> On 2025/03/10 13:43, Jason Wang wrote: >>> On Fri, Mar 7, 2025 at 7:02 PM Akihiko Odaki <akihiko.odaki@daynix.com> wrote: >>>> >>>> VIRTIO_NET_F_HASH_REPORT allows to report hash values calculated on the >>>> host. When VHOST_NET_F_VIRTIO_NET_HDR is employed, it will report no >>>> hash values (i.e., the hash_report member is always set to >>>> VIRTIO_NET_HASH_REPORT_NONE). Otherwise, the values reported by the >>>> underlying socket will be reported. >>>> >>>> VIRTIO_NET_F_HASH_REPORT requires VIRTIO_F_VERSION_1. >>>> >>>> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com> >>>> Tested-by: Lei Yang <leiyang@redhat.com> >>>> --- >>>> drivers/vhost/net.c | 49 +++++++++++++++++++++++++++++-------------------- >>>> 1 file changed, 29 insertions(+), 20 deletions(-) >>>> >>>> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c >>>> index b9b9e9d40951856d881d77ac74331d914473cd56..16b241b44f89820a42c302f3586ea6bb5e0d4289 100644 >>>> --- a/drivers/vhost/net.c >>>> +++ b/drivers/vhost/net.c >>>> @@ -73,6 +73,7 @@ enum { >>>> VHOST_NET_FEATURES = VHOST_FEATURES | >>>> (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | >>>> (1ULL << VIRTIO_NET_F_MRG_RXBUF) | >>>> + (1ULL << VIRTIO_NET_F_HASH_REPORT) | >>>> (1ULL << VIRTIO_F_ACCESS_PLATFORM) | >>>> (1ULL << VIRTIO_F_RING_RESET) >>>> }; >>>> @@ -1097,9 +1098,11 @@ static void handle_rx(struct vhost_net *net) >>>> .msg_controllen = 0, >>>> .msg_flags = MSG_DONTWAIT, >>>> }; >>>> - struct virtio_net_hdr hdr = { >>>> - .flags = 0, >>>> - .gso_type = VIRTIO_NET_HDR_GSO_NONE >>>> + struct virtio_net_hdr_v1_hash hdr = { >>>> + .hdr = { >>>> + .flags = 0, >>>> + .gso_type = VIRTIO_NET_HDR_GSO_NONE >>>> + } >>>> }; >>>> size_t total_len = 0; >>>> int err, mergeable; >>>> @@ -1110,7 +1113,6 @@ static void handle_rx(struct vhost_net *net) >>>> bool set_num_buffers; >>>> struct socket *sock; >>>> struct iov_iter fixup; >>>> - __virtio16 num_buffers; >>>> int recv_pkts = 0; >>>> >>>> mutex_lock_nested(&vq->mutex, VHOST_NET_VQ_RX); >>>> @@ -1191,30 +1193,30 @@ static void handle_rx(struct vhost_net *net) >>>> vhost_discard_vq_desc(vq, headcount); >>>> continue; >>>> } >>>> + hdr.hdr.num_buffers = cpu_to_vhost16(vq, headcount); >>>> /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ >>>> if (unlikely(vhost_hlen)) { >>>> - if (copy_to_iter(&hdr, sizeof(hdr), >>>> - &fixup) != sizeof(hdr)) { >>>> + if (copy_to_iter(&hdr, vhost_hlen, >>>> + &fixup) != vhost_hlen) { >>>> vq_err(vq, "Unable to write vnet_hdr " >>>> "at addr %p\n", vq->iov->iov_base); >>>> goto out; >>> >>> Is this an "issue" specific to RSS/HASH? If it's not, we need a separate patch. >>> >>> Honestly, I'm not sure if it's too late to fix this. >> >> There is nothing wrong with the current implementation. > > Note that I meant the vhost_hlen part, and the current code is tricky. > > The comment said: > > """ > /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ > """ > > So it tries to only offer virtio_net_hdr even if vhost_hlen is the set > to mrg_rxbuf len. > > And this patch changes this behaviour. mrg_rxbuf only adds the num_buffers field, which is always set for mrg_rxbuf. The num_buffers was not set for VIRTIO_F_VERSION_1 in the past, but this was also fixed with commit a3b9c053d82a ("vhost/net: Set num_buffers for virtio 1.0") So there is no behavioral change for existing features with this patch. Regards, Akihiko Odaki > > Thanks > >> The current >> implementation fills the header with zero except num_buffers, which it >> fills some real value. This functionality is working fine with >> VIRTIO_NET_F_MRG_RXBUF and VIRTIO_F_VERSION_1, which change the header size. >> >> Now I'm adding VIRTIO_NET_F_HASH_REPORT and it adds the hash_report >> field, which also needs to be initialized with zero, so I'm making sure >> vhost_net will also initialize it. >> >> Regards, >> Akihiko Odaki >> >>> >>> Others look fine. >>> >>> Thanks >>> >> >
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index b9b9e9d40951856d881d77ac74331d914473cd56..16b241b44f89820a42c302f3586ea6bb5e0d4289 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -73,6 +73,7 @@ enum { VHOST_NET_FEATURES = VHOST_FEATURES | (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | (1ULL << VIRTIO_NET_F_MRG_RXBUF) | + (1ULL << VIRTIO_NET_F_HASH_REPORT) | (1ULL << VIRTIO_F_ACCESS_PLATFORM) | (1ULL << VIRTIO_F_RING_RESET) }; @@ -1097,9 +1098,11 @@ static void handle_rx(struct vhost_net *net) .msg_controllen = 0, .msg_flags = MSG_DONTWAIT, }; - struct virtio_net_hdr hdr = { - .flags = 0, - .gso_type = VIRTIO_NET_HDR_GSO_NONE + struct virtio_net_hdr_v1_hash hdr = { + .hdr = { + .flags = 0, + .gso_type = VIRTIO_NET_HDR_GSO_NONE + } }; size_t total_len = 0; int err, mergeable; @@ -1110,7 +1113,6 @@ static void handle_rx(struct vhost_net *net) bool set_num_buffers; struct socket *sock; struct iov_iter fixup; - __virtio16 num_buffers; int recv_pkts = 0; mutex_lock_nested(&vq->mutex, VHOST_NET_VQ_RX); @@ -1191,30 +1193,30 @@ static void handle_rx(struct vhost_net *net) vhost_discard_vq_desc(vq, headcount); continue; } + hdr.hdr.num_buffers = cpu_to_vhost16(vq, headcount); /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ if (unlikely(vhost_hlen)) { - if (copy_to_iter(&hdr, sizeof(hdr), - &fixup) != sizeof(hdr)) { + if (copy_to_iter(&hdr, vhost_hlen, + &fixup) != vhost_hlen) { vq_err(vq, "Unable to write vnet_hdr " "at addr %p\n", vq->iov->iov_base); goto out; } - } else { + } else if (likely(set_num_buffers)) { /* Header came from socket; we'll need to patch * ->num_buffers over if VIRTIO_NET_F_MRG_RXBUF */ - iov_iter_advance(&fixup, sizeof(hdr)); + iov_iter_advance(&fixup, offsetof(struct virtio_net_hdr_v1, num_buffers)); + + if (copy_to_iter(&hdr.hdr.num_buffers, sizeof(hdr.hdr.num_buffers), + &fixup) != sizeof(hdr.hdr.num_buffers)) { + vq_err(vq, "Failed num_buffers write"); + vhost_discard_vq_desc(vq, headcount); + goto out; + } } /* TODO: Should check and handle checksum. */ - num_buffers = cpu_to_vhost16(vq, headcount); - if (likely(set_num_buffers) && - copy_to_iter(&num_buffers, sizeof num_buffers, - &fixup) != sizeof num_buffers) { - vq_err(vq, "Failed num_buffers write"); - vhost_discard_vq_desc(vq, headcount); - goto out; - } nvq->done_idx += headcount; if (nvq->done_idx > VHOST_NET_BATCH) vhost_net_signal_used(nvq); @@ -1607,10 +1609,13 @@ static int vhost_net_set_features(struct vhost_net *n, u64 features) size_t vhost_hlen, sock_hlen, hdr_len; int i; - hdr_len = (features & ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | - (1ULL << VIRTIO_F_VERSION_1))) ? - sizeof(struct virtio_net_hdr_mrg_rxbuf) : - sizeof(struct virtio_net_hdr); + if (features & (1ULL << VIRTIO_NET_F_HASH_REPORT)) + hdr_len = sizeof(struct virtio_net_hdr_v1_hash); + else if (features & ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | + (1ULL << VIRTIO_F_VERSION_1))) + hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf); + else + hdr_len = sizeof(struct virtio_net_hdr); if (features & (1 << VHOST_NET_F_VIRTIO_NET_HDR)) { /* vhost provides vnet_hdr */ vhost_hlen = hdr_len; @@ -1691,6 +1696,10 @@ static long vhost_net_ioctl(struct file *f, unsigned int ioctl, return -EFAULT; if (features & ~VHOST_NET_FEATURES) return -EOPNOTSUPP; + if ((features & ((1ULL << VIRTIO_F_VERSION_1) | + (1ULL << VIRTIO_NET_F_HASH_REPORT))) == + (1ULL << VIRTIO_NET_F_HASH_REPORT)) + return -EINVAL; return vhost_net_set_features(n, features); case VHOST_GET_BACKEND_FEATURES: features = VHOST_NET_BACKEND_FEATURES;