* [PATCH] crypto: virtio: clean up indentation, replace spaces with tab
From: Colin King @ 2018-12-30 13:46 UTC (permalink / raw)
To: Gonglei, Michael S . Tsirkin, Jason Wang, Herbert Xu,
David S . Miller, virtualization, linux-crypto
Cc: kernel-janitors, linux-kernel
From: Colin Ian King <colin.king@canonical.com>
A statement is indented with spaces and not indented enough, fix this
replacing spaces with a tab.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
drivers/crypto/virtio/virtio_crypto_algs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/crypto/virtio/virtio_crypto_algs.c b/drivers/crypto/virtio/virtio_crypto_algs.c
index 2c573d1aaa64..0704833ece92 100644
--- a/drivers/crypto/virtio/virtio_crypto_algs.c
+++ b/drivers/crypto/virtio/virtio_crypto_algs.c
@@ -406,7 +406,7 @@ __virtio_crypto_ablkcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req,
} else {
req_data->header.session_id =
cpu_to_le64(ctx->dec_sess_info.session_id);
- req_data->header.opcode =
+ req_data->header.opcode =
cpu_to_le32(VIRTIO_CRYPTO_CIPHER_DECRYPT);
}
req_data->u.sym_req.op_type = cpu_to_le32(VIRTIO_CRYPTO_SYM_OP_CIPHER);
--
2.19.1
^ permalink raw reply related
* [RFC PATCH V3 5/5] vhost: access vq metadata through kernel virtual address
From: Jason Wang @ 2018-12-29 12:46 UTC (permalink / raw)
To: mst, jasowang, kvm, virtualization, netdev, linux-kernel; +Cc: davem
In-Reply-To: <20181229124656.3900-1-jasowang@redhat.com>
It was noticed that the copy_user() friends that was used to access
virtqueue metdata tends to be very expensive for dataplane
implementation like vhost since it involves lots of software checks,
speculation barrier, hardware feature toggling (e.g SMAP). The
extra cost will be more obvious when transferring small packets since
the time spent on metadata accessing become significant..
This patch tries to eliminate those overhead by accessing them through
kernel virtual address by vmap(). To make the pages can be migrated,
instead of pinning them through GUP, we use mmu notifiers to
invalidate vmaps and re-establish vmaps during each round of metadata
prefetching in necessary. For devices that doesn't use metadata
prefetching, the memory acessors fallback to normal copy_user()
implementation gracefully. The invalidation was synchronized with
datapath through vq mutex, and in order to avoid hold vq mutex during
range checking, MMU notifier was teared down when trying to modify vq
metadata.
Note that this was only done when device IOTLB is not enabled. We
could use similar method to optimize it in the future.
Tests shows about ~24% improvement on TX PPS when using virtio-user +
vhost_net + xdp1 on TAP:
Before: ~5.0Mpps
After: ~6.1Mpps
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/vhost.c | 263 +++++++++++++++++++++++++++++++++++++++++-
drivers/vhost/vhost.h | 13 +++
2 files changed, 274 insertions(+), 2 deletions(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 54b43feef8d9..e1ecb8acf8a3 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -440,6 +440,9 @@ void vhost_dev_init(struct vhost_dev *dev,
vq->indirect = NULL;
vq->heads = NULL;
vq->dev = dev;
+ memset(&vq->avail_ring, 0, sizeof(vq->avail_ring));
+ memset(&vq->used_ring, 0, sizeof(vq->used_ring));
+ memset(&vq->desc_ring, 0, sizeof(vq->desc_ring));
mutex_init(&vq->mutex);
vhost_vq_reset(dev, vq);
if (vq->handle_kick)
@@ -510,6 +513,73 @@ static size_t vhost_get_desc_size(struct vhost_virtqueue *vq, int num)
return sizeof(*vq->desc) * num;
}
+static void vhost_uninit_vmap(struct vhost_vmap *map)
+{
+ if (map->addr)
+ vunmap(map->unmap_addr);
+
+ map->addr = NULL;
+ map->unmap_addr = NULL;
+}
+
+static int vhost_invalidate_vmap(struct vhost_virtqueue *vq,
+ struct vhost_vmap *map,
+ unsigned long ustart,
+ size_t size,
+ unsigned long start,
+ unsigned long end,
+ bool blockable)
+{
+ if (end < ustart || start > ustart - 1 + size)
+ return 0;
+
+ if (!blockable)
+ return -EAGAIN;
+
+ mutex_lock(&vq->mutex);
+ vhost_uninit_vmap(map);
+ mutex_unlock(&vq->mutex);
+
+ return 0;
+}
+
+static int vhost_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
+ struct mm_struct *mm,
+ unsigned long start,
+ unsigned long end,
+ bool blockable)
+{
+ struct vhost_dev *dev = container_of(mn, struct vhost_dev,
+ mmu_notifier);
+ int i;
+
+ for (i = 0; i < dev->nvqs; i++) {
+ struct vhost_virtqueue *vq = dev->vqs[i];
+
+ if (vhost_invalidate_vmap(vq, &vq->avail_ring,
+ (unsigned long)vq->avail,
+ vhost_get_avail_size(vq, vq->num),
+ start, end, blockable))
+ return -EAGAIN;
+ if (vhost_invalidate_vmap(vq, &vq->desc_ring,
+ (unsigned long)vq->desc,
+ vhost_get_desc_size(vq, vq->num),
+ start, end, blockable))
+ return -EAGAIN;
+ if (vhost_invalidate_vmap(vq, &vq->used_ring,
+ (unsigned long)vq->used,
+ vhost_get_used_size(vq, vq->num),
+ start, end, blockable))
+ return -EAGAIN;
+ }
+
+ return 0;
+}
+
+static const struct mmu_notifier_ops vhost_mmu_notifier_ops = {
+ .invalidate_range_start = vhost_mmu_notifier_invalidate_range_start,
+};
+
/* Caller should have device mutex */
long vhost_dev_set_owner(struct vhost_dev *dev)
{
@@ -541,7 +611,14 @@ long vhost_dev_set_owner(struct vhost_dev *dev)
if (err)
goto err_cgroup;
+ dev->mmu_notifier.ops = &vhost_mmu_notifier_ops;
+ err = mmu_notifier_register(&dev->mmu_notifier, dev->mm);
+ if (err)
+ goto err_mmu_notifier;
+
return 0;
+err_mmu_notifier:
+ vhost_dev_free_iovecs(dev);
err_cgroup:
kthread_stop(worker);
dev->worker = NULL;
@@ -632,6 +709,72 @@ static void vhost_clear_msg(struct vhost_dev *dev)
spin_unlock(&dev->iotlb_lock);
}
+static int vhost_init_vmap(struct vhost_vmap *map, unsigned long uaddr,
+ size_t size, int write)
+{
+ struct page **pages;
+ int npages = DIV_ROUND_UP(size, PAGE_SIZE);
+ int npinned;
+ void *vaddr;
+ int err = 0;
+
+ pages = kmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
+ if (!pages)
+ return -ENOMEM;
+
+ npinned = get_user_pages_fast(uaddr, npages, write, pages);
+ if (npinned != npages) {
+ err = -EFAULT;
+ goto err;
+ }
+
+ vaddr = vmap(pages, npages, VM_MAP, PAGE_KERNEL);
+ if (!vaddr) {
+ err = EFAULT;
+ goto err;
+ }
+
+ map->addr = vaddr + (uaddr & (PAGE_SIZE - 1));
+ map->unmap_addr = vaddr;
+
+err:
+ /* Don't pin pages, mmu notifier will notify us about page
+ * migration.
+ */
+ if (npinned > 0)
+ release_pages(pages, npinned);
+ kfree(pages);
+ return err;
+}
+
+static void vhost_clean_vmaps(struct vhost_virtqueue *vq)
+{
+ vhost_uninit_vmap(&vq->avail_ring);
+ vhost_uninit_vmap(&vq->desc_ring);
+ vhost_uninit_vmap(&vq->used_ring);
+}
+
+static int vhost_setup_avail_vmap(struct vhost_virtqueue *vq,
+ unsigned long avail)
+{
+ return vhost_init_vmap(&vq->avail_ring, avail,
+ vhost_get_avail_size(vq, vq->num), false);
+}
+
+static int vhost_setup_desc_vmap(struct vhost_virtqueue *vq,
+ unsigned long desc)
+{
+ return vhost_init_vmap(&vq->desc_ring, desc,
+ vhost_get_desc_size(vq, vq->num), false);
+}
+
+static int vhost_setup_used_vmap(struct vhost_virtqueue *vq,
+ unsigned long used)
+{
+ return vhost_init_vmap(&vq->used_ring, used,
+ vhost_get_used_size(vq, vq->num), true);
+}
+
void vhost_dev_cleanup(struct vhost_dev *dev)
{
int i;
@@ -661,8 +804,12 @@ void vhost_dev_cleanup(struct vhost_dev *dev)
kthread_stop(dev->worker);
dev->worker = NULL;
}
- if (dev->mm)
+ if (dev->mm) {
+ mmu_notifier_unregister(&dev->mmu_notifier, dev->mm);
mmput(dev->mm);
+ }
+ for (i = 0; i < dev->nvqs; i++)
+ vhost_clean_vmaps(dev->vqs[i]);
dev->mm = NULL;
}
EXPORT_SYMBOL_GPL(vhost_dev_cleanup);
@@ -891,6 +1038,16 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq,
static inline int vhost_put_avail_event(struct vhost_virtqueue *vq)
{
+ if (!vq->iotlb) {
+ struct vring_used *used = vq->used_ring.addr;
+
+ if (likely(used)) {
+ *((__virtio16 *)&used->ring[vq->num]) =
+ cpu_to_vhost16(vq, vq->avail_idx);
+ return 0;
+ }
+ }
+
return vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx),
vhost_avail_event(vq));
}
@@ -899,6 +1056,16 @@ static inline int vhost_put_used(struct vhost_virtqueue *vq,
struct vring_used_elem *head, int idx,
int count)
{
+ if (!vq->iotlb) {
+ struct vring_used *used = vq->used_ring.addr;
+
+ if (likely(used)) {
+ memcpy(used->ring + idx, head,
+ count * sizeof(*head));
+ return 0;
+ }
+ }
+
return vhost_copy_to_user(vq, vq->used->ring + idx, head,
count * sizeof(*head));
}
@@ -906,6 +1073,15 @@ static inline int vhost_put_used(struct vhost_virtqueue *vq,
static inline int vhost_put_used_flags(struct vhost_virtqueue *vq)
{
+ if (!vq->iotlb) {
+ struct vring_used *used = vq->used_ring.addr;
+
+ if (likely(used)) {
+ used->flags = cpu_to_vhost16(vq, vq->used_flags);
+ return 0;
+ }
+ }
+
return vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags),
&vq->used->flags);
}
@@ -913,6 +1089,15 @@ static inline int vhost_put_used_flags(struct vhost_virtqueue *vq)
static inline int vhost_put_used_idx(struct vhost_virtqueue *vq)
{
+ if (!vq->iotlb) {
+ struct vring_used *used = vq->used_ring.addr;
+
+ if (likely(used)) {
+ used->idx = cpu_to_vhost16(vq, vq->last_used_idx);
+ return 0;
+ }
+ }
+
return vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx),
&vq->used->idx);
}
@@ -958,12 +1143,30 @@ static void vhost_dev_unlock_vqs(struct vhost_dev *d)
static inline int vhost_get_avail_idx(struct vhost_virtqueue *vq,
__virtio16 *idx)
{
+ if (!vq->iotlb) {
+ struct vring_avail *avail = vq->avail_ring.addr;
+
+ if (likely(avail)) {
+ *idx = avail->idx;
+ return 0;
+ }
+ }
+
return vhost_get_avail(vq, *idx, &vq->avail->idx);
}
static inline int vhost_get_avail_head(struct vhost_virtqueue *vq,
__virtio16 *head, int idx)
{
+ if (!vq->iotlb) {
+ struct vring_avail *avail = vq->avail_ring.addr;
+
+ if (likely(avail)) {
+ *head = avail->ring[idx & (vq->num - 1)];
+ return 0;
+ }
+ }
+
return vhost_get_avail(vq, *head,
&vq->avail->ring[idx & (vq->num - 1)]);
}
@@ -971,24 +1174,60 @@ static inline int vhost_get_avail_head(struct vhost_virtqueue *vq,
static inline int vhost_get_avail_flags(struct vhost_virtqueue *vq,
__virtio16 *flags)
{
+ if (!vq->iotlb) {
+ struct vring_avail *avail = vq->avail_ring.addr;
+
+ if (likely(avail)) {
+ *flags = avail->flags;
+ return 0;
+ }
+ }
+
return vhost_get_avail(vq, *flags, &vq->avail->flags);
}
static inline int vhost_get_used_event(struct vhost_virtqueue *vq,
__virtio16 *event)
{
+ if (!vq->iotlb) {
+ struct vring_avail *avail = vq->avail_ring.addr;
+
+ if (likely(avail)) {
+ *event = (__virtio16)avail->ring[vq->num];
+ return 0;
+ }
+ }
+
return vhost_get_avail(vq, *event, vhost_used_event(vq));
}
static inline int vhost_get_used_idx(struct vhost_virtqueue *vq,
__virtio16 *idx)
{
+ if (!vq->iotlb) {
+ struct vring_used *used = vq->used_ring.addr;
+
+ if (likely(used)) {
+ *idx = used->idx;
+ return 0;
+ }
+ }
+
return vhost_get_used(vq, *idx, &vq->used->idx);
}
static inline int vhost_get_desc(struct vhost_virtqueue *vq,
struct vring_desc *desc, int idx)
{
+ if (!vq->iotlb) {
+ struct vring_desc *d = vq->desc_ring.addr;
+
+ if (likely(d)) {
+ *desc = *(d + idx);
+ return 0;
+ }
+ }
+
return vhost_copy_from_user(vq, desc, vq->desc + idx, sizeof(*desc));
}
@@ -1325,8 +1564,16 @@ int vq_meta_prefetch(struct vhost_virtqueue *vq)
{
unsigned int num = vq->num;
- if (!vq->iotlb)
+ if (!vq->iotlb) {
+ if (unlikely(!vq->avail_ring.addr))
+ vhost_setup_avail_vmap(vq, (unsigned long)vq->avail);
+ if (unlikely(!vq->desc_ring.addr))
+ vhost_setup_desc_vmap(vq, (unsigned long)vq->desc);
+ if (unlikely(!vq->used_ring.addr))
+ vhost_setup_used_vmap(vq, (unsigned long)vq->used);
+
return 1;
+ }
return iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->desc,
vhost_get_desc_size(vq, num), VHOST_ADDR_DESC) &&
@@ -1478,6 +1725,13 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg
mutex_lock(&vq->mutex);
+ /* Unregister MMU notifer to allow invalidation callback
+ * can access vq->avail, vq->desc , vq->used and vq->num
+ * without holding vq->mutex.
+ */
+ if (d->mm)
+ mmu_notifier_unregister(&d->mmu_notifier, d->mm);
+
switch (ioctl) {
case VHOST_SET_VRING_NUM:
/* Resizing ring with an active backend?
@@ -1494,6 +1748,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg
r = -EINVAL;
break;
}
+ vhost_clean_vmaps(vq);
vq->num = s.num;
break;
case VHOST_SET_VRING_BASE:
@@ -1571,6 +1826,8 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg
}
}
+ vhost_clean_vmaps(vq);
+
vq->log_used = !!(a.flags & (0x1 << VHOST_VRING_F_LOG));
vq->desc = (void __user *)(unsigned long)a.desc_user_addr;
vq->avail = (void __user *)(unsigned long)a.avail_user_addr;
@@ -1651,6 +1908,8 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg
if (pollstart && vq->handle_kick)
r = vhost_poll_start(&vq->poll, vq->kick);
+ if (d->mm)
+ mmu_notifier_register(&d->mmu_notifier, d->mm);
mutex_unlock(&vq->mutex);
if (pollstop && vq->handle_kick)
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index 0d1ff977a43e..00f016a4f198 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -12,6 +12,8 @@
#include <linux/virtio_config.h>
#include <linux/virtio_ring.h>
#include <linux/atomic.h>
+#include <linux/pagemap.h>
+#include <linux/mmu_notifier.h>
struct vhost_work;
typedef void (*vhost_work_fn_t)(struct vhost_work *work);
@@ -80,6 +82,11 @@ enum vhost_uaddr_type {
VHOST_NUM_ADDRS = 3,
};
+struct vhost_vmap {
+ void *addr;
+ void *unmap_addr;
+};
+
/* The virtqueue structure describes a queue attached to a device. */
struct vhost_virtqueue {
struct vhost_dev *dev;
@@ -90,6 +97,11 @@ struct vhost_virtqueue {
struct vring_desc __user *desc;
struct vring_avail __user *avail;
struct vring_used __user *used;
+
+ struct vhost_vmap avail_ring;
+ struct vhost_vmap desc_ring;
+ struct vhost_vmap used_ring;
+
const struct vhost_umem_node *meta_iotlb[VHOST_NUM_ADDRS];
struct file *kick;
struct eventfd_ctx *call_ctx;
@@ -158,6 +170,7 @@ struct vhost_msg_node {
struct vhost_dev {
struct mm_struct *mm;
+ struct mmu_notifier mmu_notifier;
struct mutex mutex;
struct vhost_virtqueue **vqs;
int nvqs;
--
2.17.1
^ permalink raw reply related
* [RFC PATCH V3 4/5] vhost: introduce helpers to get the size of metadata area
From: Jason Wang @ 2018-12-29 12:46 UTC (permalink / raw)
To: mst, jasowang, kvm, virtualization, netdev, linux-kernel; +Cc: davem
In-Reply-To: <20181229124656.3900-1-jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/vhost.c | 46 ++++++++++++++++++++++++++-----------------
1 file changed, 28 insertions(+), 18 deletions(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 27b5c03feaac..54b43feef8d9 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -489,6 +489,27 @@ bool vhost_dev_has_owner(struct vhost_dev *dev)
}
EXPORT_SYMBOL_GPL(vhost_dev_has_owner);
+static size_t vhost_get_avail_size(struct vhost_virtqueue *vq, int num)
+{
+ size_t event = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
+
+ return sizeof(*vq->avail) +
+ sizeof(*vq->avail->ring) * num + event;
+}
+
+static size_t vhost_get_used_size(struct vhost_virtqueue *vq, int num)
+{
+ size_t event = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
+
+ return sizeof(*vq->used) +
+ sizeof(*vq->used->ring) * num + event;
+}
+
+static size_t vhost_get_desc_size(struct vhost_virtqueue *vq, int num)
+{
+ return sizeof(*vq->desc) * num;
+}
+
/* Caller should have device mutex */
long vhost_dev_set_owner(struct vhost_dev *dev)
{
@@ -1248,13 +1269,9 @@ static bool vq_access_ok(struct vhost_virtqueue *vq, unsigned int num,
struct vring_used __user *used)
{
- size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
-
- return access_ok(VERIFY_READ, desc, num * sizeof *desc) &&
- access_ok(VERIFY_READ, avail,
- sizeof *avail + num * sizeof *avail->ring + s) &&
- access_ok(VERIFY_WRITE, used,
- sizeof *used + num * sizeof *used->ring + s);
+ return access_ok(VERIFY_READ, desc, vhost_get_desc_size(vq, num)) &&
+ access_ok(VERIFY_READ, avail, vhost_get_avail_size(vq, num)) &&
+ access_ok(VERIFY_WRITE, used, vhost_get_used_size(vq, num));
}
static void vhost_vq_meta_update(struct vhost_virtqueue *vq,
@@ -1306,22 +1323,18 @@ static bool iotlb_access_ok(struct vhost_virtqueue *vq,
int vq_meta_prefetch(struct vhost_virtqueue *vq)
{
- size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
unsigned int num = vq->num;
if (!vq->iotlb)
return 1;
return iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->desc,
- num * sizeof(*vq->desc), VHOST_ADDR_DESC) &&
+ vhost_get_desc_size(vq, num), VHOST_ADDR_DESC) &&
iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->avail,
- sizeof *vq->avail +
- num * sizeof(*vq->avail->ring) + s,
+ vhost_get_avail_size(vq, num),
VHOST_ADDR_AVAIL) &&
iotlb_access_ok(vq, VHOST_ACCESS_WO, (u64)(uintptr_t)vq->used,
- sizeof *vq->used +
- num * sizeof(*vq->used->ring) + s,
- VHOST_ADDR_USED);
+ vhost_get_used_size(vq, num), VHOST_ADDR_USED);
}
EXPORT_SYMBOL_GPL(vq_meta_prefetch);
@@ -1338,13 +1351,10 @@ EXPORT_SYMBOL_GPL(vhost_log_access_ok);
static bool vq_log_access_ok(struct vhost_virtqueue *vq,
void __user *log_base)
{
- size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
-
return vq_memory_access_ok(log_base, vq->umem,
vhost_has_feature(vq, VHOST_F_LOG_ALL)) &&
(!vq->log_used || log_access_ok(log_base, vq->log_addr,
- sizeof *vq->used +
- vq->num * sizeof *vq->used->ring + s));
+ vhost_get_used_size(vq, vq->num)));
}
/* Can we start vq? */
--
2.17.1
^ permalink raw reply related
* [RFC PATCH V3 3/5] vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch()
From: Jason Wang @ 2018-12-29 12:46 UTC (permalink / raw)
To: mst, jasowang, kvm, virtualization, netdev, linux-kernel; +Cc: davem
In-Reply-To: <20181229124656.3900-1-jasowang@redhat.com>
Rename the function to be more accurate since it actually tries to
prefetch vq metadata address in IOTLB. And this will be used by
following patch to prefetch metadata virtual addresses.
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/net.c | 4 ++--
drivers/vhost/vhost.c | 4 ++--
drivers/vhost/vhost.h | 2 +-
3 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 36f3d0f49e60..0b4b3deab5aa 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -971,7 +971,7 @@ static void handle_tx(struct vhost_net *net)
if (!sock)
goto out;
- if (!vq_iotlb_prefetch(vq))
+ if (!vq_meta_prefetch(vq))
goto out;
vhost_disable_notify(&net->dev, vq);
@@ -1140,7 +1140,7 @@ static void handle_rx(struct vhost_net *net)
if (!sock)
goto out;
- if (!vq_iotlb_prefetch(vq))
+ if (!vq_meta_prefetch(vq))
goto out;
vhost_disable_notify(&net->dev, vq);
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 337ce6f5a098..27b5c03feaac 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1304,7 +1304,7 @@ static bool iotlb_access_ok(struct vhost_virtqueue *vq,
return true;
}
-int vq_iotlb_prefetch(struct vhost_virtqueue *vq)
+int vq_meta_prefetch(struct vhost_virtqueue *vq)
{
size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
unsigned int num = vq->num;
@@ -1323,7 +1323,7 @@ int vq_iotlb_prefetch(struct vhost_virtqueue *vq)
num * sizeof(*vq->used->ring) + s,
VHOST_ADDR_USED);
}
-EXPORT_SYMBOL_GPL(vq_iotlb_prefetch);
+EXPORT_SYMBOL_GPL(vq_meta_prefetch);
/* Can we log writes? */
/* Caller should have device mutex but not vq mutex */
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index 466ef7542291..0d1ff977a43e 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -206,7 +206,7 @@ bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);
int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
unsigned int log_num, u64 len);
-int vq_iotlb_prefetch(struct vhost_virtqueue *vq);
+int vq_meta_prefetch(struct vhost_virtqueue *vq);
struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type);
void vhost_enqueue_msg(struct vhost_dev *dev,
--
2.17.1
^ permalink raw reply related
* [RFC PATCH V3 2/5] vhost: fine grain userspace memory accessors
From: Jason Wang @ 2018-12-29 12:46 UTC (permalink / raw)
To: mst, jasowang, kvm, virtualization, netdev, linux-kernel; +Cc: davem
In-Reply-To: <20181229124656.3900-1-jasowang@redhat.com>
This is used to hide the metadata address from virtqueue helpers. This
will allow to implement a vmap based fast accessing to metadata.
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/vhost.c | 94 +++++++++++++++++++++++++++++++++++--------
1 file changed, 77 insertions(+), 17 deletions(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index f179b5ee14c4..337ce6f5a098 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -868,6 +868,34 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq,
ret; \
})
+static inline int vhost_put_avail_event(struct vhost_virtqueue *vq)
+{
+ return vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx),
+ vhost_avail_event(vq));
+}
+
+static inline int vhost_put_used(struct vhost_virtqueue *vq,
+ struct vring_used_elem *head, int idx,
+ int count)
+{
+ return vhost_copy_to_user(vq, vq->used->ring + idx, head,
+ count * sizeof(*head));
+}
+
+static inline int vhost_put_used_flags(struct vhost_virtqueue *vq)
+
+{
+ return vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags),
+ &vq->used->flags);
+}
+
+static inline int vhost_put_used_idx(struct vhost_virtqueue *vq)
+
+{
+ return vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx),
+ &vq->used->idx);
+}
+
#define vhost_get_user(vq, x, ptr, type) \
({ \
int ret; \
@@ -906,6 +934,43 @@ static void vhost_dev_unlock_vqs(struct vhost_dev *d)
mutex_unlock(&d->vqs[i]->mutex);
}
+static inline int vhost_get_avail_idx(struct vhost_virtqueue *vq,
+ __virtio16 *idx)
+{
+ return vhost_get_avail(vq, *idx, &vq->avail->idx);
+}
+
+static inline int vhost_get_avail_head(struct vhost_virtqueue *vq,
+ __virtio16 *head, int idx)
+{
+ return vhost_get_avail(vq, *head,
+ &vq->avail->ring[idx & (vq->num - 1)]);
+}
+
+static inline int vhost_get_avail_flags(struct vhost_virtqueue *vq,
+ __virtio16 *flags)
+{
+ return vhost_get_avail(vq, *flags, &vq->avail->flags);
+}
+
+static inline int vhost_get_used_event(struct vhost_virtqueue *vq,
+ __virtio16 *event)
+{
+ return vhost_get_avail(vq, *event, vhost_used_event(vq));
+}
+
+static inline int vhost_get_used_idx(struct vhost_virtqueue *vq,
+ __virtio16 *idx)
+{
+ return vhost_get_used(vq, *idx, &vq->used->idx);
+}
+
+static inline int vhost_get_desc(struct vhost_virtqueue *vq,
+ struct vring_desc *desc, int idx)
+{
+ return vhost_copy_from_user(vq, desc, vq->desc + idx, sizeof(*desc));
+}
+
static int vhost_new_umem_range(struct vhost_umem *umem,
u64 start, u64 size, u64 end,
u64 userspace_addr, int perm)
@@ -1761,8 +1826,7 @@ EXPORT_SYMBOL_GPL(vhost_log_write);
static int vhost_update_used_flags(struct vhost_virtqueue *vq)
{
void __user *used;
- if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags),
- &vq->used->flags) < 0)
+ if (vhost_put_used_flags(vq))
return -EFAULT;
if (unlikely(vq->log_used)) {
/* Make sure the flag is seen before log. */
@@ -1780,8 +1844,7 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq)
static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event)
{
- if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx),
- vhost_avail_event(vq)))
+ if (vhost_put_avail_event(vq))
return -EFAULT;
if (unlikely(vq->log_used)) {
void __user *used;
@@ -1818,7 +1881,7 @@ int vhost_vq_init_access(struct vhost_virtqueue *vq)
r = -EFAULT;
goto err;
}
- r = vhost_get_used(vq, last_used_idx, &vq->used->idx);
+ r = vhost_get_used_idx(vq, &last_used_idx);
if (r) {
vq_err(vq, "Can't access used idx at %p\n",
&vq->used->idx);
@@ -2017,7 +2080,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq,
last_avail_idx = vq->last_avail_idx;
if (vq->avail_idx == vq->last_avail_idx) {
- if (unlikely(vhost_get_avail(vq, avail_idx, &vq->avail->idx))) {
+ if (unlikely(vhost_get_avail_idx(vq, &avail_idx))) {
vq_err(vq, "Failed to access avail idx at %p\n",
&vq->avail->idx);
return -EFAULT;
@@ -2044,8 +2107,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq,
/* Grab the next descriptor number they're advertising, and increment
* the index we've seen. */
- if (unlikely(vhost_get_avail(vq, ring_head,
- &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) {
+ if (unlikely(vhost_get_avail_head(vq, &ring_head, last_avail_idx))) {
vq_err(vq, "Failed to read head: idx %d address %p\n",
last_avail_idx,
&vq->avail->ring[last_avail_idx % vq->num]);
@@ -2080,8 +2142,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq,
i, vq->num, head);
return -EINVAL;
}
- ret = vhost_copy_from_user(vq, &desc, vq->desc + i,
- sizeof desc);
+ ret = vhost_get_desc(vq, &desc, i);
if (unlikely(ret)) {
vq_err(vq, "Failed to get descriptor: idx %d addr %p\n",
i, vq->desc + i);
@@ -2174,7 +2235,7 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq,
start = vq->last_used_idx & (vq->num - 1);
used = vq->used->ring + start;
- if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) {
+ if (vhost_put_used(vq, heads, start, count)) {
vq_err(vq, "Failed to write used");
return -EFAULT;
}
@@ -2218,8 +2279,7 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
/* Make sure buffer is written before we update index. */
smp_wmb();
- if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx),
- &vq->used->idx)) {
+ if (vhost_put_used_idx(vq)) {
vq_err(vq, "Failed to increment used idx");
return -EFAULT;
}
@@ -2253,7 +2313,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) {
__virtio16 flags;
- if (vhost_get_avail(vq, flags, &vq->avail->flags)) {
+ if (vhost_get_avail_flags(vq, &flags)) {
vq_err(vq, "Failed to get flags");
return true;
}
@@ -2267,7 +2327,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
if (unlikely(!v))
return true;
- if (vhost_get_avail(vq, event, vhost_used_event(vq))) {
+ if (vhost_get_used_event(vq, &event)) {
vq_err(vq, "Failed to get used event idx");
return true;
}
@@ -2312,7 +2372,7 @@ bool vhost_vq_avail_empty(struct vhost_dev *dev, struct vhost_virtqueue *vq)
if (vq->avail_idx != vq->last_avail_idx)
return false;
- r = vhost_get_avail(vq, avail_idx, &vq->avail->idx);
+ r = vhost_get_avail_idx(vq, &avail_idx);
if (unlikely(r))
return false;
vq->avail_idx = vhost16_to_cpu(vq, avail_idx);
@@ -2348,7 +2408,7 @@ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
/* They could have slipped one in as we were doing that: make
* sure it's written, then check again. */
smp_mb();
- r = vhost_get_avail(vq, avail_idx, &vq->avail->idx);
+ r = vhost_get_avail_idx(vq, &avail_idx);
if (r) {
vq_err(vq, "Failed to check avail idx at %p: %d\n",
&vq->avail->idx, r);
--
2.17.1
^ permalink raw reply related
* [RFC PATCH V3 1/5] vhost: generalize adding used elem
From: Jason Wang @ 2018-12-29 12:46 UTC (permalink / raw)
To: mst, jasowang, kvm, virtualization, netdev, linux-kernel; +Cc: davem
In-Reply-To: <20181229124656.3900-1-jasowang@redhat.com>
Use one generic vhost_copy_to_user() instead of two dedicated
accessor. This will simplify the conversion to fine grain
accessors. About 2% improvement of PPS were seen during vitio-user
txonly test.
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/vhost.c | 11 +----------
1 file changed, 1 insertion(+), 10 deletions(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 55e5aa662ad5..f179b5ee14c4 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -2174,16 +2174,7 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq,
start = vq->last_used_idx & (vq->num - 1);
used = vq->used->ring + start;
- if (count == 1) {
- if (vhost_put_user(vq, heads[0].id, &used->id)) {
- vq_err(vq, "Failed to write used id");
- return -EFAULT;
- }
- if (vhost_put_user(vq, heads[0].len, &used->len)) {
- vq_err(vq, "Failed to write used len");
- return -EFAULT;
- }
- } else if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) {
+ if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) {
vq_err(vq, "Failed to write used");
return -EFAULT;
}
--
2.17.1
^ permalink raw reply related
* [RFC PATCH V3 0/5] Hi:
From: Jason Wang @ 2018-12-29 12:46 UTC (permalink / raw)
To: mst, jasowang, kvm, virtualization, netdev, linux-kernel; +Cc: davem
This series tries to access virtqueue metadata through kernel virtual
address instead of copy_user() friends since they had too much
overheads like checks, spec barriers or even hardware feature
toggling.
Test shows about 24% improvement on TX PPS. It should benefit other
cases as well.
Changes from V2:
- fix buggy range overlapping check
- tear down MMU notifier during vhost ioctl to make sure invalidation
request can read metadata userspace address and vq size without
holding vq mutex.
Changes from V1:
- instead of pinning pages, use MMU notifier to invalidate vmaps and
remap duing metadata prefetch
- fix build warning on MIPS
Jason Wang (5):
vhost: generalize adding used elem
vhost: fine grain userspace memory accessors
vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch()
vhost: introduce helpers to get the size of metadata area
vhost: access vq metadata through kernel virtual address
drivers/vhost/net.c | 4 +-
drivers/vhost/vhost.c | 416 +++++++++++++++++++++++++++++++++++++-----
drivers/vhost/vhost.h | 15 +-
3 files changed, 384 insertions(+), 51 deletions(-)
--
2.17.1
^ permalink raw reply
* Re: [RFC PATCH V2 3/3] vhost: access vq metadata through kernel virtual address
From: Jason Wang @ 2018-12-29 12:41 UTC (permalink / raw)
To: David Miller; +Cc: netdev, virtualization, linux-kernel, kvm, mst
In-Reply-To: <20181228.113444.2162917443074434767.davem@davemloft.net>
On 2018/12/29 上午3:34, David Miller wrote:
> From: Jason Wang <jasowang@redhat.com>
> Date: Fri, 28 Dec 2018 15:55:37 +0800
>
>> +static int vhost_invalidate_vmap(struct vhost_virtqueue *vq,
>> + struct vhost_vmap *map,
>> + unsigned long uaddr,
>> + unsigned long start,
>> + unsigned long end,
>> + bool blockable)
>> +{
>> + if (start < uaddr && end >= uaddr) {
>> + if (!blockable)
>> + return -EAGAIN;
>> + mutex_lock(&vq->mutex);
>> + if (map->addr)
>> + vunmap(map->unmap_addr);
>> + map->addr = NULL;
>> + map->unmap_addr = NULL;
>> + mutex_unlock(&vq->mutex);
>> + }
>> +
>> + return 0;
>> +}
> What are the rules for these invalidate operations?
>
> Can there be partial overlaps? If so, wouldn't you need some way of
> keeping track of the partially overlapping unmaps so that once all of
> the invalidates covering the range occur you properly cleanup and do
> the vunmap()?
Yes, there can be partial overlap, so the check is buggy. We will remap
the whole range in vq_meta_prefetch() before datapath path try to use
them, so there's no need to track partial mapping here.
I spot another bug that the caller will access vq->avail without
synchronized with vhost ioctl. Since we don't want to hold vq mutex for
each invalidation, I will tear down MMU notifier during vhost ioctl to
make sure invalidation request can access them without hold vq mutex.
Thanks
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply
* RE: [PATCH v1 0/2] Virtio: fix some vq allocation issues
From: Wang, Wei W @ 2018-12-29 2:45 UTC (permalink / raw)
To: Christian Borntraeger, virtio-dev@lists.oasis-open.org,
linux-kernel@vger.kernel.org,
virtualization@lists.linux-foundation.org, kvm@vger.kernel.org,
mst@redhat.com, cohuck@redhat.com
Cc: Halil Pasic, pbonzini@redhat.com, dgilbert@redhat.com
In-Reply-To: <c6746307-fae5-7652-af8d-19f560fc31d9@de.ibm.com>
On Friday, December 28, 2018 3:57 PM, Christian Borntraeger wrote:
> On 28.12.2018 03:26, Wei Wang wrote:
> > Some vqs don't need to be allocated when the related feature bits are
> > disabled. Callers notice the vq allocation layer by setting the
> > related names[i] to be NULL.
> >
> > This patch series fixes the find_vqs implementations to handle this case.
>
> So the random crashes during boot are gone.
> What still does not work is actually using the balloon.
>
> So in the qemu monitor using lets say "balloon 1000" will hang the guest.
> Seems to be a deadlock in the virtio-ccw code. We seem to call the config
> code in the interrupt handler.
Yes. It reads a config register from the interrupt handler. Do you know why ccw doesn't support it and has some internal lock that caused the deadlock issue?
Best,
Wei
^ permalink raw reply
* Re: [RFC PATCH V2 3/3] vhost: access vq metadata through kernel virtual address
From: David Miller @ 2018-12-28 19:34 UTC (permalink / raw)
To: jasowang; +Cc: netdev, virtualization, linux-kernel, kvm, mst
In-Reply-To: <20181228075537.21402-4-jasowang@redhat.com>
From: Jason Wang <jasowang@redhat.com>
Date: Fri, 28 Dec 2018 15:55:37 +0800
> +static int vhost_invalidate_vmap(struct vhost_virtqueue *vq,
> + struct vhost_vmap *map,
> + unsigned long uaddr,
> + unsigned long start,
> + unsigned long end,
> + bool blockable)
> +{
> + if (start < uaddr && end >= uaddr) {
> + if (!blockable)
> + return -EAGAIN;
> + mutex_lock(&vq->mutex);
> + if (map->addr)
> + vunmap(map->unmap_addr);
> + map->addr = NULL;
> + map->unmap_addr = NULL;
> + mutex_unlock(&vq->mutex);
> + }
> +
> + return 0;
> +}
What are the rules for these invalidate operations?
Can there be partial overlaps? If so, wouldn't you need some way of
keeping track of the partially overlapping unmaps so that once all of
the invalidates covering the range occur you properly cleanup and do
the vunmap()?
^ permalink raw reply
* Re: [PATCH v37 1/3] virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT
From: Christian Borntraeger @ 2018-12-28 8:03 UTC (permalink / raw)
To: Wei Wang, virtio-dev, linux-kernel, virtualization, kvm, linux-mm,
mst, mhocko, akpm, dgilbert
Cc: yang.zhang.wz, riel, quan.xu0, liliang.opensource, Cornelia Huck,
Halil Pasic, pbonzini, nilal, torvalds
In-Reply-To: <5C259485.2030809@intel.com>
On 28.12.2018 04:12, Wei Wang wrote:
> On 12/27/2018 08:03 PM, Christian Borntraeger wrote:
>> On 27.08.2018 03:32, Wei Wang wrote:
>>> static int init_vqs(struct virtio_balloon *vb)
>>> {
>>> - struct virtqueue *vqs[3];
>>> - vq_callback_t *callbacks[] = { balloon_ack, balloon_ack, stats_request };
>>> - static const char * const names[] = { "inflate", "deflate", "stats" };
>>> - int err, nvqs;
>>> + struct virtqueue *vqs[VIRTIO_BALLOON_VQ_MAX];
>>> + vq_callback_t *callbacks[VIRTIO_BALLOON_VQ_MAX];
>>> + const char *names[VIRTIO_BALLOON_VQ_MAX];
>>> + int err;
>>>
>>> /*
>>> - * We expect two virtqueues: inflate and deflate, and
>>> - * optionally stat.
>>> + * Inflateq and deflateq are used unconditionally. The names[]
>>> + * will be NULL if the related feature is not enabled, which will
>>> + * cause no allocation for the corresponding virtqueue in find_vqs.
>>> */
>> This might be true for virtio-pci, but it is not for virtio-ccw.
>
> Hi Christian,
>
>
> Please try the fix patches: https://lkml.org/lkml/2018/12/27/336
See answer to that thread. It fixes the random boot crashes.
There is still the regression that ballooning does no longer work on
s390 (see the call trace).
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply
* Re: [PATCH v1 0/2] Virtio: fix some vq allocation issues
From: Christian Borntraeger @ 2018-12-28 7:57 UTC (permalink / raw)
To: Wei Wang, virtio-dev, linux-kernel, virtualization, kvm, mst,
cohuck
Cc: Halil Pasic, pbonzini, dgilbert
In-Reply-To: <1545963986-11280-1-git-send-email-wei.w.wang@intel.com>
On 28.12.2018 03:26, Wei Wang wrote:
> Some vqs don't need to be allocated when the related feature bits are
> disabled. Callers notice the vq allocation layer by setting the related
> names[i] to be NULL.
>
> This patch series fixes the find_vqs implementations to handle this case.
So the random crashes during boot are gone.
What still does not work is actually using the balloon.
So in the qemu monitor using lets say "balloon 1000" will hang the guest.
Seems to be a deadlock in the virtio-ccw code. We seem to call the
config code in the interrupt handler.
crash> bt
PID: 0 TASK: d9a400 CPU: 0 COMMAND: "swapper/0"
LOWCORE INFO:
-psw : 0x0404c00180000000 0x0000000000116472
-function : smp_yield_cpu at 116472
-prefix : 0x7fffc000
-cpu timer: 0x7fffffcc8c0af5be
-clock cmp: 0x720a4e4002831000
-general registers:
000000000000000000 000000000000000000
0x000000000000009c 0x0000000000fac2b0
0x0000000000000015 0xffffffffffffffe2
0x000003e000100000 0x0000000000000001
000000000000000000 0x0000000000000001
0x00000000000003e8 0x000000000f85c020
000000000000000000 0x0000000000000001
0x0000000000116464 0x000003e00035fad0
-access registers:
0000000000 0000000000 0000000000 0000000000
0000000000 0000000000 0000000000 0000000000
0000000000 0000000000 0000000000 0000000000
0000000000 0000000000 0000000000 0000000000
-control registers:
0x0080000014866a10 0x0000000000fbc007
0x0000000000100140 000000000000000000
0x000000000000ffff 0x0000000000100140
0x0000000031000000 0x000000000f9281c3
000000000000000000 000000000000000000
000000000000000000 000000000000000000
000000000000000000 0x0000000000fbc007
0x00000000db000000 0x0000000000100280
-floating point registers:
000000000000000000 0x000002aa374b0298
0x0000000000000001 0x0000000000000010
0x00000000000001ae 0x000000000000000f
0x000002aa46056010 0x000002aa460681c0
0x000003ffd867d590 0x000003ffdca7c818
0x000003ffd867d58f 0x000003fff6ffdc60
0x000003ffd867dad8 0x000003ffdca7c5e8
0x000003ffd867dadc 0x000003ffdca7c818
#0 [3e00035faf8] arch_spin_lock_wait at a7bd52
#1 [3e00035fb50] ccw_io_helper at 9130ea
#2 [3e00035fbd0] virtio_ccw_get_config at 914a28
#3 [3e00035fc30] virtballoon_changed at 76e776
#4 [3e00035fc70] virtio_config_changed at 76aabc
#5 [3e00035fca8] virtio_ccw_int_handler at 914ede
#6 [3e00035fd18] ccw_device_irq at 8941d4
#7 [3e00035fd48] do_cio_interrupt at 885906
#8 [3e00035fd80] __handle_irq_event_percpu at 1b3c22
#9 [3e00035fdf0] handle_irq_event_percpu at 1b3e1e
#10 [3e00035fe28] handle_percpu_irq at 1b87d8
#11 [3e00035fe58] generic_handle_irq at 1b2ce6
#12 [3e00035fe70] do_IRQ at 10c3b2
#13 [3e00035fea8] io_int_handler at a86b3c
PSW: 0404c00180000000 00000000001034f6 (enabled_wait+70)
GPRS: ffffffffffffffff 0000000000000000 000000007ff70200 0706c00180000000
000000000000000c 000001bf6f331c58 ffffffffffffffff 0000000000000000
0000000000000000 0000000000000000 0000000000000000 0000000000000001
000000007ff70200 0000000000a8b2f0 00000000001034f6 000003e000317e00
#0 [3e000317e28] arch_cpu_idle at 103842
#1 [3e000317e48] do_idle at 17ad18
#2 [3e000317e80] cpu_startup_entry at 17af16
#3 [3e000317ea8] arch_call_rest_init at eac934
>
> Wei Wang (2):
> virtio_pci: use queue idx instead of array idx to set up the vq
> virtio: don't allocate vqs when names[i] = NULL
>
> drivers/misc/mic/vop/vop_main.c | 9 +++++++--
> drivers/remoteproc/remoteproc_virtio.c | 9 +++++++--
> drivers/s390/virtio/virtio_ccw.c | 12 +++++++++---
> drivers/virtio/virtio_mmio.c | 9 +++++++--
> drivers/virtio/virtio_pci_common.c | 8 ++++----
> 5 files changed, 34 insertions(+), 13 deletions(-)
>
^ permalink raw reply
* [RFC PATCH V2 3/3] vhost: access vq metadata through kernel virtual address
From: Jason Wang @ 2018-12-28 7:55 UTC (permalink / raw)
To: mst, jasowang, kvm, virtualization, netdev, linux-kernel
In-Reply-To: <20181228075537.21402-1-jasowang@redhat.com>
It was noticed that the copy_user() friends that was used to access
virtqueue metdata tends to be very expensive for dataplane
implementation like vhost since it involves lots of software checks,
speculation barrier, hardware feature toggling (e.g SMAP). The
extra cost will be more obvious when transferring small packets since
the time spent on metadata accessing become significant..
This patch tries to eliminate those overhead by accessing them through
kernel virtual address by vmap(). To make the pages can be migrated,
instead of pinning them through GUP, we use mmu notifiers to
invalidate vmaps and re-establish vmaps during each round of metadata
prefetching in necessary. For devices that doesn't use metadata
prefetch, the memory acessors fallback to normal copy_user()
implementation gracefully.
Note that this was only done when device IOTLB is not enabled. We
could use similar method to optimize it in the future.
Tests shows about ~24% improvement on TX PPS when using virtio-user +
vhost_net + xdp1 on TAP:
Before: ~5.0Mpps
After: ~6.1Mpps
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/net.c | 4 +-
drivers/vhost/vhost.c | 259 +++++++++++++++++++++++++++++++++++++++++-
drivers/vhost/vhost.h | 15 ++-
3 files changed, 271 insertions(+), 7 deletions(-)
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 36f3d0f49e60..0b4b3deab5aa 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -971,7 +971,7 @@ static void handle_tx(struct vhost_net *net)
if (!sock)
goto out;
- if (!vq_iotlb_prefetch(vq))
+ if (!vq_meta_prefetch(vq))
goto out;
vhost_disable_notify(&net->dev, vq);
@@ -1140,7 +1140,7 @@ static void handle_rx(struct vhost_net *net)
if (!sock)
goto out;
- if (!vq_iotlb_prefetch(vq))
+ if (!vq_meta_prefetch(vq))
goto out;
vhost_disable_notify(&net->dev, vq);
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 337ce6f5a098..46a889b61a4d 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -440,6 +440,9 @@ void vhost_dev_init(struct vhost_dev *dev,
vq->indirect = NULL;
vq->heads = NULL;
vq->dev = dev;
+ memset(&vq->avail_ring, 0, sizeof(vq->avail_ring));
+ memset(&vq->used_ring, 0, sizeof(vq->used_ring));
+ memset(&vq->desc_ring, 0, sizeof(vq->desc_ring));
mutex_init(&vq->mutex);
vhost_vq_reset(dev, vq);
if (vq->handle_kick)
@@ -489,6 +492,61 @@ bool vhost_dev_has_owner(struct vhost_dev *dev)
}
EXPORT_SYMBOL_GPL(vhost_dev_has_owner);
+static int vhost_invalidate_vmap(struct vhost_virtqueue *vq,
+ struct vhost_vmap *map,
+ unsigned long uaddr,
+ unsigned long start,
+ unsigned long end,
+ bool blockable)
+{
+ if (start < uaddr && end >= uaddr) {
+ if (!blockable)
+ return -EAGAIN;
+ mutex_lock(&vq->mutex);
+ if (map->addr)
+ vunmap(map->unmap_addr);
+ map->addr = NULL;
+ map->unmap_addr = NULL;
+ mutex_unlock(&vq->mutex);
+ }
+
+ return 0;
+}
+
+static int vhost_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
+ struct mm_struct *mm,
+ unsigned long start,
+ unsigned long end,
+ bool blockable)
+{
+ struct vhost_dev *dev = container_of(mn, struct vhost_dev,
+ mmu_notifier);
+ int i;
+
+ for (i = 0; i < dev->nvqs; i++) {
+ struct vhost_virtqueue *vq = dev->vqs[i];
+
+ if (vhost_invalidate_vmap(vq, &vq->avail_ring,
+ (unsigned long)vq->avail,
+ start, end, blockable))
+ return -EAGAIN;
+ if (vhost_invalidate_vmap(vq, &vq->desc_ring,
+ (unsigned long)vq->desc,
+ start, end, blockable))
+ return -EAGAIN;
+ if (vhost_invalidate_vmap(vq, &vq->used_ring,
+ (unsigned long)vq->used,
+ start, end, blockable))
+ return -EAGAIN;
+ }
+
+ return 0;
+}
+
+static const struct mmu_notifier_ops vhost_mmu_notifier_ops = {
+ .invalidate_range_start = vhost_mmu_notifier_invalidate_range_start,
+};
+
/* Caller should have device mutex */
long vhost_dev_set_owner(struct vhost_dev *dev)
{
@@ -520,7 +578,14 @@ long vhost_dev_set_owner(struct vhost_dev *dev)
if (err)
goto err_cgroup;
+ dev->mmu_notifier.ops = &vhost_mmu_notifier_ops;
+ err = mmu_notifier_register(&dev->mmu_notifier, dev->mm);
+ if (err)
+ goto err_mmu_notifier;
+
return 0;
+err_mmu_notifier:
+ vhost_dev_free_iovecs(dev);
err_cgroup:
kthread_stop(worker);
dev->worker = NULL;
@@ -611,6 +676,87 @@ static void vhost_clear_msg(struct vhost_dev *dev)
spin_unlock(&dev->iotlb_lock);
}
+static int vhost_init_vmap(struct vhost_vmap *map, unsigned long uaddr,
+ size_t size, int write)
+{
+ struct page **pages;
+ int npages = DIV_ROUND_UP(size, PAGE_SIZE);
+ int npinned;
+ void *vaddr;
+ int err = 0;
+
+ pages = kmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
+ if (!pages)
+ return -ENOMEM;
+
+ npinned = get_user_pages_fast(uaddr, npages, write, pages);
+ if (npinned != npages) {
+ err = -EFAULT;
+ goto err;
+ }
+
+ vaddr = vmap(pages, npages, VM_MAP, PAGE_KERNEL);
+ if (!vaddr) {
+ err = EFAULT;
+ goto err;
+ }
+
+ map->addr = vaddr + (uaddr & (PAGE_SIZE - 1));
+ map->unmap_addr = vaddr;
+
+err:
+ /* Don't pin pages, mmu notifier will notify us about page
+ * migration.
+ */
+ if (npinned > 0)
+ release_pages(pages, npinned);
+ kfree(pages);
+ return err;
+}
+
+static void vhost_uninit_vmap(struct vhost_vmap *map)
+{
+ if (map->addr) {
+ vunmap(map->unmap_addr);
+ map->addr = NULL;
+ }
+}
+
+static void vhost_clean_vmaps(struct vhost_virtqueue *vq)
+{
+ vhost_uninit_vmap(&vq->avail_ring);
+ vhost_uninit_vmap(&vq->desc_ring);
+ vhost_uninit_vmap(&vq->used_ring);
+}
+
+static int vhost_setup_avail_vmap(struct vhost_virtqueue *vq,
+ unsigned long avail)
+{
+ size_t event = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
+ size_t avail_size = sizeof(*vq->avail) +
+ sizeof(*vq->avail->ring) * vq->num + event;
+
+ return vhost_init_vmap(&vq->avail_ring, avail, avail_size, false);
+}
+
+static int vhost_setup_desc_vmap(struct vhost_virtqueue *vq,
+ unsigned long desc)
+{
+ size_t desc_size = sizeof(*vq->desc) * vq->num;
+
+ return vhost_init_vmap(&vq->desc_ring, desc, desc_size, false);
+}
+
+static int vhost_setup_used_vmap(struct vhost_virtqueue *vq,
+ unsigned long used)
+{
+ size_t event = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
+ size_t used_size = sizeof(*vq->used) +
+ sizeof(*vq->used->ring) * vq->num + event;
+
+ return vhost_init_vmap(&vq->used_ring, used, used_size, true);
+}
+
void vhost_dev_cleanup(struct vhost_dev *dev)
{
int i;
@@ -623,6 +769,7 @@ void vhost_dev_cleanup(struct vhost_dev *dev)
if (dev->vqs[i]->call_ctx)
eventfd_ctx_put(dev->vqs[i]->call_ctx);
vhost_vq_reset(dev, dev->vqs[i]);
+ vhost_clean_vmaps(dev->vqs[i]);
}
vhost_dev_free_iovecs(dev);
if (dev->log_ctx)
@@ -640,8 +787,10 @@ void vhost_dev_cleanup(struct vhost_dev *dev)
kthread_stop(dev->worker);
dev->worker = NULL;
}
- if (dev->mm)
+ if (dev->mm) {
+ mmu_notifier_unregister(&dev->mmu_notifier, dev->mm);
mmput(dev->mm);
+ }
dev->mm = NULL;
}
EXPORT_SYMBOL_GPL(vhost_dev_cleanup);
@@ -870,6 +1019,16 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq,
static inline int vhost_put_avail_event(struct vhost_virtqueue *vq)
{
+ if (!vq->iotlb) {
+ struct vring_used *used = vq->used_ring.addr;
+
+ if (likely(used)) {
+ *((__virtio16 *)&used->ring[vq->num]) =
+ cpu_to_vhost16(vq, vq->avail_idx);
+ return 0;
+ }
+ }
+
return vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx),
vhost_avail_event(vq));
}
@@ -878,6 +1037,16 @@ static inline int vhost_put_used(struct vhost_virtqueue *vq,
struct vring_used_elem *head, int idx,
int count)
{
+ if (!vq->iotlb) {
+ struct vring_used *used = vq->used_ring.addr;
+
+ if (likely(used)) {
+ memcpy(used->ring + idx, head,
+ count * sizeof(*head));
+ return 0;
+ }
+ }
+
return vhost_copy_to_user(vq, vq->used->ring + idx, head,
count * sizeof(*head));
}
@@ -885,6 +1054,15 @@ static inline int vhost_put_used(struct vhost_virtqueue *vq,
static inline int vhost_put_used_flags(struct vhost_virtqueue *vq)
{
+ if (!vq->iotlb) {
+ struct vring_used *used = vq->used_ring.addr;
+
+ if (likely(used)) {
+ used->flags = cpu_to_vhost16(vq, vq->used_flags);
+ return 0;
+ }
+ }
+
return vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags),
&vq->used->flags);
}
@@ -892,6 +1070,15 @@ static inline int vhost_put_used_flags(struct vhost_virtqueue *vq)
static inline int vhost_put_used_idx(struct vhost_virtqueue *vq)
{
+ if (!vq->iotlb) {
+ struct vring_used *used = vq->used_ring.addr;
+
+ if (likely(used)) {
+ used->idx = cpu_to_vhost16(vq, vq->last_used_idx);
+ return 0;
+ }
+ }
+
return vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx),
&vq->used->idx);
}
@@ -937,12 +1124,30 @@ static void vhost_dev_unlock_vqs(struct vhost_dev *d)
static inline int vhost_get_avail_idx(struct vhost_virtqueue *vq,
__virtio16 *idx)
{
+ if (!vq->iotlb) {
+ struct vring_avail *avail = vq->avail_ring.addr;
+
+ if (likely(avail)) {
+ *idx = avail->idx;
+ return 0;
+ }
+ }
+
return vhost_get_avail(vq, *idx, &vq->avail->idx);
}
static inline int vhost_get_avail_head(struct vhost_virtqueue *vq,
__virtio16 *head, int idx)
{
+ if (!vq->iotlb) {
+ struct vring_avail *avail = vq->avail_ring.addr;
+
+ if (likely(avail)) {
+ *head = avail->ring[idx & (vq->num - 1)];
+ return 0;
+ }
+ }
+
return vhost_get_avail(vq, *head,
&vq->avail->ring[idx & (vq->num - 1)]);
}
@@ -950,24 +1155,60 @@ static inline int vhost_get_avail_head(struct vhost_virtqueue *vq,
static inline int vhost_get_avail_flags(struct vhost_virtqueue *vq,
__virtio16 *flags)
{
+ if (!vq->iotlb) {
+ struct vring_avail *avail = vq->avail_ring.addr;
+
+ if (likely(avail)) {
+ *flags = avail->flags;
+ return 0;
+ }
+ }
+
return vhost_get_avail(vq, *flags, &vq->avail->flags);
}
static inline int vhost_get_used_event(struct vhost_virtqueue *vq,
__virtio16 *event)
{
+ if (!vq->iotlb) {
+ struct vring_avail *avail = vq->avail_ring.addr;
+
+ if (likely(avail)) {
+ *event = (__virtio16)avail->ring[vq->num];
+ return 0;
+ }
+ }
+
return vhost_get_avail(vq, *event, vhost_used_event(vq));
}
static inline int vhost_get_used_idx(struct vhost_virtqueue *vq,
__virtio16 *idx)
{
+ if (!vq->iotlb) {
+ struct vring_used *used = vq->used_ring.addr;
+
+ if (likely(used)) {
+ *idx = used->idx;
+ return 0;
+ }
+ }
+
return vhost_get_used(vq, *idx, &vq->used->idx);
}
static inline int vhost_get_desc(struct vhost_virtqueue *vq,
struct vring_desc *desc, int idx)
{
+ if (!vq->iotlb) {
+ struct vring_desc *d = vq->desc_ring.addr;
+
+ if (likely(d)) {
+ *desc = *(d + idx);
+ return 0;
+ }
+ }
+
return vhost_copy_from_user(vq, desc, vq->desc + idx, sizeof(*desc));
}
@@ -1304,13 +1545,21 @@ static bool iotlb_access_ok(struct vhost_virtqueue *vq,
return true;
}
-int vq_iotlb_prefetch(struct vhost_virtqueue *vq)
+int vq_meta_prefetch(struct vhost_virtqueue *vq)
{
size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
unsigned int num = vq->num;
- if (!vq->iotlb)
+ if (!vq->iotlb) {
+ if (unlikely(!vq->avail_ring.addr))
+ vhost_setup_avail_vmap(vq, (unsigned long)vq->avail);
+ if (unlikely(!vq->desc_ring.addr))
+ vhost_setup_desc_vmap(vq, (unsigned long)vq->desc);
+ if (unlikely(!vq->used_ring.addr))
+ vhost_setup_used_vmap(vq, (unsigned long)vq->used);
+
return 1;
+ }
return iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->desc,
num * sizeof(*vq->desc), VHOST_ADDR_DESC) &&
@@ -1323,7 +1572,7 @@ int vq_iotlb_prefetch(struct vhost_virtqueue *vq)
num * sizeof(*vq->used->ring) + s,
VHOST_ADDR_USED);
}
-EXPORT_SYMBOL_GPL(vq_iotlb_prefetch);
+EXPORT_SYMBOL_GPL(vq_meta_prefetch);
/* Can we log writes? */
/* Caller should have device mutex but not vq mutex */
@@ -1561,6 +1810,8 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg
}
}
+ vhost_clean_vmaps(vq);
+
vq->log_used = !!(a.flags & (0x1 << VHOST_VRING_F_LOG));
vq->desc = (void __user *)(unsigned long)a.desc_user_addr;
vq->avail = (void __user *)(unsigned long)a.avail_user_addr;
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index 466ef7542291..00f016a4f198 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -12,6 +12,8 @@
#include <linux/virtio_config.h>
#include <linux/virtio_ring.h>
#include <linux/atomic.h>
+#include <linux/pagemap.h>
+#include <linux/mmu_notifier.h>
struct vhost_work;
typedef void (*vhost_work_fn_t)(struct vhost_work *work);
@@ -80,6 +82,11 @@ enum vhost_uaddr_type {
VHOST_NUM_ADDRS = 3,
};
+struct vhost_vmap {
+ void *addr;
+ void *unmap_addr;
+};
+
/* The virtqueue structure describes a queue attached to a device. */
struct vhost_virtqueue {
struct vhost_dev *dev;
@@ -90,6 +97,11 @@ struct vhost_virtqueue {
struct vring_desc __user *desc;
struct vring_avail __user *avail;
struct vring_used __user *used;
+
+ struct vhost_vmap avail_ring;
+ struct vhost_vmap desc_ring;
+ struct vhost_vmap used_ring;
+
const struct vhost_umem_node *meta_iotlb[VHOST_NUM_ADDRS];
struct file *kick;
struct eventfd_ctx *call_ctx;
@@ -158,6 +170,7 @@ struct vhost_msg_node {
struct vhost_dev {
struct mm_struct *mm;
+ struct mmu_notifier mmu_notifier;
struct mutex mutex;
struct vhost_virtqueue **vqs;
int nvqs;
@@ -206,7 +219,7 @@ bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);
int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
unsigned int log_num, u64 len);
-int vq_iotlb_prefetch(struct vhost_virtqueue *vq);
+int vq_meta_prefetch(struct vhost_virtqueue *vq);
struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type);
void vhost_enqueue_msg(struct vhost_dev *dev,
--
2.17.1
^ permalink raw reply related
* [RFC PATCH V2 2/3] vhost: fine grain userspace memory accessors
From: Jason Wang @ 2018-12-28 7:55 UTC (permalink / raw)
To: mst, jasowang, kvm, virtualization, netdev, linux-kernel
In-Reply-To: <20181228075537.21402-1-jasowang@redhat.com>
This is used to hide the metadata address from virtqueue helpers. This
will allow to implement a vmap based fast accessing to metadata.
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/vhost.c | 94 +++++++++++++++++++++++++++++++++++--------
1 file changed, 77 insertions(+), 17 deletions(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index f179b5ee14c4..337ce6f5a098 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -868,6 +868,34 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq,
ret; \
})
+static inline int vhost_put_avail_event(struct vhost_virtqueue *vq)
+{
+ return vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx),
+ vhost_avail_event(vq));
+}
+
+static inline int vhost_put_used(struct vhost_virtqueue *vq,
+ struct vring_used_elem *head, int idx,
+ int count)
+{
+ return vhost_copy_to_user(vq, vq->used->ring + idx, head,
+ count * sizeof(*head));
+}
+
+static inline int vhost_put_used_flags(struct vhost_virtqueue *vq)
+
+{
+ return vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags),
+ &vq->used->flags);
+}
+
+static inline int vhost_put_used_idx(struct vhost_virtqueue *vq)
+
+{
+ return vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx),
+ &vq->used->idx);
+}
+
#define vhost_get_user(vq, x, ptr, type) \
({ \
int ret; \
@@ -906,6 +934,43 @@ static void vhost_dev_unlock_vqs(struct vhost_dev *d)
mutex_unlock(&d->vqs[i]->mutex);
}
+static inline int vhost_get_avail_idx(struct vhost_virtqueue *vq,
+ __virtio16 *idx)
+{
+ return vhost_get_avail(vq, *idx, &vq->avail->idx);
+}
+
+static inline int vhost_get_avail_head(struct vhost_virtqueue *vq,
+ __virtio16 *head, int idx)
+{
+ return vhost_get_avail(vq, *head,
+ &vq->avail->ring[idx & (vq->num - 1)]);
+}
+
+static inline int vhost_get_avail_flags(struct vhost_virtqueue *vq,
+ __virtio16 *flags)
+{
+ return vhost_get_avail(vq, *flags, &vq->avail->flags);
+}
+
+static inline int vhost_get_used_event(struct vhost_virtqueue *vq,
+ __virtio16 *event)
+{
+ return vhost_get_avail(vq, *event, vhost_used_event(vq));
+}
+
+static inline int vhost_get_used_idx(struct vhost_virtqueue *vq,
+ __virtio16 *idx)
+{
+ return vhost_get_used(vq, *idx, &vq->used->idx);
+}
+
+static inline int vhost_get_desc(struct vhost_virtqueue *vq,
+ struct vring_desc *desc, int idx)
+{
+ return vhost_copy_from_user(vq, desc, vq->desc + idx, sizeof(*desc));
+}
+
static int vhost_new_umem_range(struct vhost_umem *umem,
u64 start, u64 size, u64 end,
u64 userspace_addr, int perm)
@@ -1761,8 +1826,7 @@ EXPORT_SYMBOL_GPL(vhost_log_write);
static int vhost_update_used_flags(struct vhost_virtqueue *vq)
{
void __user *used;
- if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags),
- &vq->used->flags) < 0)
+ if (vhost_put_used_flags(vq))
return -EFAULT;
if (unlikely(vq->log_used)) {
/* Make sure the flag is seen before log. */
@@ -1780,8 +1844,7 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq)
static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event)
{
- if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx),
- vhost_avail_event(vq)))
+ if (vhost_put_avail_event(vq))
return -EFAULT;
if (unlikely(vq->log_used)) {
void __user *used;
@@ -1818,7 +1881,7 @@ int vhost_vq_init_access(struct vhost_virtqueue *vq)
r = -EFAULT;
goto err;
}
- r = vhost_get_used(vq, last_used_idx, &vq->used->idx);
+ r = vhost_get_used_idx(vq, &last_used_idx);
if (r) {
vq_err(vq, "Can't access used idx at %p\n",
&vq->used->idx);
@@ -2017,7 +2080,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq,
last_avail_idx = vq->last_avail_idx;
if (vq->avail_idx == vq->last_avail_idx) {
- if (unlikely(vhost_get_avail(vq, avail_idx, &vq->avail->idx))) {
+ if (unlikely(vhost_get_avail_idx(vq, &avail_idx))) {
vq_err(vq, "Failed to access avail idx at %p\n",
&vq->avail->idx);
return -EFAULT;
@@ -2044,8 +2107,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq,
/* Grab the next descriptor number they're advertising, and increment
* the index we've seen. */
- if (unlikely(vhost_get_avail(vq, ring_head,
- &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) {
+ if (unlikely(vhost_get_avail_head(vq, &ring_head, last_avail_idx))) {
vq_err(vq, "Failed to read head: idx %d address %p\n",
last_avail_idx,
&vq->avail->ring[last_avail_idx % vq->num]);
@@ -2080,8 +2142,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq,
i, vq->num, head);
return -EINVAL;
}
- ret = vhost_copy_from_user(vq, &desc, vq->desc + i,
- sizeof desc);
+ ret = vhost_get_desc(vq, &desc, i);
if (unlikely(ret)) {
vq_err(vq, "Failed to get descriptor: idx %d addr %p\n",
i, vq->desc + i);
@@ -2174,7 +2235,7 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq,
start = vq->last_used_idx & (vq->num - 1);
used = vq->used->ring + start;
- if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) {
+ if (vhost_put_used(vq, heads, start, count)) {
vq_err(vq, "Failed to write used");
return -EFAULT;
}
@@ -2218,8 +2279,7 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
/* Make sure buffer is written before we update index. */
smp_wmb();
- if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx),
- &vq->used->idx)) {
+ if (vhost_put_used_idx(vq)) {
vq_err(vq, "Failed to increment used idx");
return -EFAULT;
}
@@ -2253,7 +2313,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) {
__virtio16 flags;
- if (vhost_get_avail(vq, flags, &vq->avail->flags)) {
+ if (vhost_get_avail_flags(vq, &flags)) {
vq_err(vq, "Failed to get flags");
return true;
}
@@ -2267,7 +2327,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
if (unlikely(!v))
return true;
- if (vhost_get_avail(vq, event, vhost_used_event(vq))) {
+ if (vhost_get_used_event(vq, &event)) {
vq_err(vq, "Failed to get used event idx");
return true;
}
@@ -2312,7 +2372,7 @@ bool vhost_vq_avail_empty(struct vhost_dev *dev, struct vhost_virtqueue *vq)
if (vq->avail_idx != vq->last_avail_idx)
return false;
- r = vhost_get_avail(vq, avail_idx, &vq->avail->idx);
+ r = vhost_get_avail_idx(vq, &avail_idx);
if (unlikely(r))
return false;
vq->avail_idx = vhost16_to_cpu(vq, avail_idx);
@@ -2348,7 +2408,7 @@ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
/* They could have slipped one in as we were doing that: make
* sure it's written, then check again. */
smp_mb();
- r = vhost_get_avail(vq, avail_idx, &vq->avail->idx);
+ r = vhost_get_avail_idx(vq, &avail_idx);
if (r) {
vq_err(vq, "Failed to check avail idx at %p: %d\n",
&vq->avail->idx, r);
--
2.17.1
^ permalink raw reply related
* [RFC PATCH V2 1/3] vhost: generalize adding used elem
From: Jason Wang @ 2018-12-28 7:55 UTC (permalink / raw)
To: mst, jasowang, kvm, virtualization, netdev, linux-kernel
In-Reply-To: <20181228075537.21402-1-jasowang@redhat.com>
Use one generic vhost_copy_to_user() instead of two dedicated
accessor. This will simplify the conversion to fine grain
accessors. About 2% improvement of PPS were seen during vitio-user
txonly test.
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/vhost.c | 11 +----------
1 file changed, 1 insertion(+), 10 deletions(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 55e5aa662ad5..f179b5ee14c4 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -2174,16 +2174,7 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq,
start = vq->last_used_idx & (vq->num - 1);
used = vq->used->ring + start;
- if (count == 1) {
- if (vhost_put_user(vq, heads[0].id, &used->id)) {
- vq_err(vq, "Failed to write used id");
- return -EFAULT;
- }
- if (vhost_put_user(vq, heads[0].len, &used->len)) {
- vq_err(vq, "Failed to write used len");
- return -EFAULT;
- }
- } else if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) {
+ if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) {
vq_err(vq, "Failed to write used");
return -EFAULT;
}
--
2.17.1
^ permalink raw reply related
* [RFC PATCH V2 0/3] vhost: accelerate metadata access through vmap()
From: Jason Wang @ 2018-12-28 7:55 UTC (permalink / raw)
To: mst, jasowang, kvm, virtualization, netdev, linux-kernel
Hi:
This series tries to access virtqueue metadata through kernel virtual
address instead of copy_user() friends since they had too much
overheads like checks, spec barriers or even hardware feature
toggling.
Test shows about 24% improvement on TX PPS. It should benefit other
cases as well.
Changes from V1:
- instead of pinning pages, use MMU notifier to invalidate vmaps and
remap duing metadata prefetch
- fix build warning on MIPS
Please review
Jason Wang (3):
vhost: generalize adding used elem
vhost: fine grain userspace memory accessors
vhost: access vq metadata through kernel virtual address
drivers/vhost/net.c | 4 +-
drivers/vhost/vhost.c | 362 ++++++++++++++++++++++++++++++++++++++----
drivers/vhost/vhost.h | 15 +-
3 files changed, 348 insertions(+), 33 deletions(-)
--
2.17.1
^ permalink raw reply
* Re: [PATCH v37 0/3] Virtio-balloon: support free page reporting
From: Wei Wang @ 2018-12-28 6:41 UTC (permalink / raw)
To: Christian Borntraeger, virtio-dev, linux-kernel, virtualization,
kvm, linux-mm, mst, mhocko, akpm, dgilbert
Cc: yang.zhang.wz, riel, quan.xu0, liliang.opensource, Cornelia Huck,
Halil Pasic, pbonzini, nilal, torvalds
In-Reply-To: <e79b5c3d-aa89-6b99-00b1-c92c85fe214c@de.ibm.com>
On 12/27/2018 08:17 PM, Christian Borntraeger wrote:
>
> On 27.12.2018 12:59, Christian Borntraeger wrote:
>> On 27.12.2018 12:31, Christian Borntraeger wrote:
>>> This patch triggers random crashes in the guest kernel on s390 early during boot.
>>> No migration and no setting of the balloon is involved.
>>>
>> Adding Conny and Halil,
>>
>> As the QEMU provides no PAGE_HINT feature yet, this quick hack makes the
>> guest boot fine again:
>>
>>
>> diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
>> index 728ecd1eea305..aa2e1864c5736 100644
>> --- a/drivers/virtio/virtio_balloon.c
>> +++ b/drivers/virtio/virtio_balloon.c
>> @@ -492,7 +492,7 @@ static int init_vqs(struct virtio_balloon *vb)
>> callbacks[VIRTIO_BALLOON_VQ_FREE_PAGE] = NULL;
>> }
>>
>> - err = vb->vdev->config->find_vqs(vb->vdev, VIRTIO_BALLOON_VQ_MAX,
>> + err = vb->vdev->config->find_vqs(vb->vdev, 3, //VIRTIO_BALLOON_VQ_MAX,
>> vqs, callbacks, names, NULL, NULL);
>> if (err)
>> return err;
>>
>>
>> To me it looks like that virtio_ccw_find_vqs will abort if any of the virtqueues
>> that it is been asked for does not exist (including the earlier ones).
>>
> This "hack" makes the random crashes go away, but the balloon interface itself
> does not work. (setting the value to anything will hang the guest).
> As patch 1 also modifies the main path, there seem to be additional issues, maybe
> endianess
>
> Looking at things like
>
> + vb->cmd_id_received = VIRTIO_BALLOON_CMD_ID_STOP;
> + vb->cmd_id_active = cpu_to_virtio32(vb->vdev,
> + VIRTIO_BALLOON_CMD_ID_STOP);
> + vb->cmd_id_stop = cpu_to_virtio32(vb->vdev,
> + VIRTIO_BALLOON_CMD_ID_STOP);
>
>
> Why is cmd_id_received not using cpu_to_virtio32?
>
That conversion is only needed when we need to send the value to the device.
cmd_id_received doesn't need to be sent to the device.
Best,
Wei
^ permalink raw reply
* Re: [PATCH v37 1/3] virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT
From: Wei Wang @ 2018-12-28 3:12 UTC (permalink / raw)
To: Christian Borntraeger, virtio-dev, linux-kernel, virtualization,
kvm, linux-mm, mst, mhocko, akpm, dgilbert
Cc: yang.zhang.wz, riel, quan.xu0, liliang.opensource, Cornelia Huck,
Halil Pasic, pbonzini, nilal, torvalds
In-Reply-To: <49d706f7-a0ee-e571-7d02-bcadac5ce742@de.ibm.com>
On 12/27/2018 08:03 PM, Christian Borntraeger wrote:
> On 27.08.2018 03:32, Wei Wang wrote:
>> static int init_vqs(struct virtio_balloon *vb)
>> {
>> - struct virtqueue *vqs[3];
>> - vq_callback_t *callbacks[] = { balloon_ack, balloon_ack, stats_request };
>> - static const char * const names[] = { "inflate", "deflate", "stats" };
>> - int err, nvqs;
>> + struct virtqueue *vqs[VIRTIO_BALLOON_VQ_MAX];
>> + vq_callback_t *callbacks[VIRTIO_BALLOON_VQ_MAX];
>> + const char *names[VIRTIO_BALLOON_VQ_MAX];
>> + int err;
>>
>> /*
>> - * We expect two virtqueues: inflate and deflate, and
>> - * optionally stat.
>> + * Inflateq and deflateq are used unconditionally. The names[]
>> + * will be NULL if the related feature is not enabled, which will
>> + * cause no allocation for the corresponding virtqueue in find_vqs.
>> */
> This might be true for virtio-pci, but it is not for virtio-ccw.
Hi Christian,
Please try the fix patches: https://lkml.org/lkml/2018/12/27/336
Best,
Wei
^ permalink raw reply
* [PATCH v1 2/2] virtio: don't allocate vqs when names[i] = NULL
From: Wei Wang @ 2018-12-28 2:26 UTC (permalink / raw)
To: virtio-dev, linux-kernel, virtualization, kvm, mst, cohuck
Cc: dgilbert, pbonzini
In-Reply-To: <1545963986-11280-1-git-send-email-wei.w.wang@intel.com>
Some vqs may not need to be allocated when their related feature bits
are disabled. So callers may pass in such vqs with "names = NULL".
Then we skip such vq allocations.
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
---
drivers/misc/mic/vop/vop_main.c | 9 +++++++--
drivers/remoteproc/remoteproc_virtio.c | 9 +++++++--
drivers/s390/virtio/virtio_ccw.c | 12 +++++++++---
drivers/virtio/virtio_mmio.c | 9 +++++++--
4 files changed, 30 insertions(+), 9 deletions(-)
diff --git a/drivers/misc/mic/vop/vop_main.c b/drivers/misc/mic/vop/vop_main.c
index 6b212c8..2bfa3a9 100644
--- a/drivers/misc/mic/vop/vop_main.c
+++ b/drivers/misc/mic/vop/vop_main.c
@@ -394,16 +394,21 @@ static int vop_find_vqs(struct virtio_device *dev, unsigned nvqs,
struct _vop_vdev *vdev = to_vopvdev(dev);
struct vop_device *vpdev = vdev->vpdev;
struct mic_device_ctrl __iomem *dc = vdev->dc;
- int i, err, retry;
+ int i, err, retry, queue_idx = 0;
/* We must have this many virtqueues. */
if (nvqs > ioread8(&vdev->desc->num_vq))
return -ENOENT;
for (i = 0; i < nvqs; ++i) {
+ if (!names[i]) {
+ vqs[i] = NULL;
+ continue;
+ }
+
dev_dbg(_vop_dev(vdev), "%s: %d: %s\n",
__func__, i, names[i]);
- vqs[i] = vop_find_vq(dev, i, callbacks[i], names[i],
+ vqs[i] = vop_find_vq(dev, queue_idx++, callbacks[i], names[i],
ctx ? ctx[i] : false);
if (IS_ERR(vqs[i])) {
err = PTR_ERR(vqs[i]);
diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c
index 183fc42..2d7cd344 100644
--- a/drivers/remoteproc/remoteproc_virtio.c
+++ b/drivers/remoteproc/remoteproc_virtio.c
@@ -153,10 +153,15 @@ static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
const bool * ctx,
struct irq_affinity *desc)
{
- int i, ret;
+ int i, ret, queue_idx = 0;
for (i = 0; i < nvqs; ++i) {
- vqs[i] = rp_find_vq(vdev, i, callbacks[i], names[i],
+ if (!names[i]) {
+ vqs[i] = NULL;
+ continue;
+ }
+
+ vqs[i] = rp_find_vq(vdev, queue_idx++, callbacks[i], names[i],
ctx ? ctx[i] : false);
if (IS_ERR(vqs[i])) {
ret = PTR_ERR(vqs[i]);
diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
index fc9dbad..ae1d56d 100644
--- a/drivers/s390/virtio/virtio_ccw.c
+++ b/drivers/s390/virtio/virtio_ccw.c
@@ -635,7 +635,7 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
{
struct virtio_ccw_device *vcdev = to_vc_device(vdev);
unsigned long *indicatorp = NULL;
- int ret, i;
+ int ret, i, queue_idx = 0;
struct ccw1 *ccw;
ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
@@ -643,8 +643,14 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
return -ENOMEM;
for (i = 0; i < nvqs; ++i) {
- vqs[i] = virtio_ccw_setup_vq(vdev, i, callbacks[i], names[i],
- ctx ? ctx[i] : false, ccw);
+ if (!names[i]) {
+ vqs[i] = NULL;
+ continue;
+ }
+
+ vqs[i] = virtio_ccw_setup_vq(vdev, queue_idx++, callbacks[i],
+ names[i], ctx ? ctx[i] : false,
+ ccw);
if (IS_ERR(vqs[i])) {
ret = PTR_ERR(vqs[i]);
vqs[i] = NULL;
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index 4cd9ea5..d9dd0f78 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -468,7 +468,7 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
{
struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
unsigned int irq = platform_get_irq(vm_dev->pdev, 0);
- int i, err;
+ int i, err, queue_idx = 0;
err = request_irq(irq, vm_interrupt, IRQF_SHARED,
dev_name(&vdev->dev), vm_dev);
@@ -476,7 +476,12 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
return err;
for (i = 0; i < nvqs; ++i) {
- vqs[i] = vm_setup_vq(vdev, i, callbacks[i], names[i],
+ if (!names[i]) {
+ vqs[i] = NULL;
+ continue;
+ }
+
+ vqs[i] = vm_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
ctx ? ctx[i] : false);
if (IS_ERR(vqs[i])) {
vm_del_vqs(vdev);
--
2.7.4
^ permalink raw reply related
* [PATCH v1 1/2] virtio_pci: use queue idx instead of array idx to set up the vq
From: Wei Wang @ 2018-12-28 2:26 UTC (permalink / raw)
To: virtio-dev, linux-kernel, virtualization, kvm, mst, cohuck
Cc: dgilbert, pbonzini
In-Reply-To: <1545963986-11280-1-git-send-email-wei.w.wang@intel.com>
When find_vqs, there will be no vq[i] allocation if its corresponding
names[i] is NULL. For example, the caller may pass in names[i] (i=4)
with names[2] being NULL because the related feature bit is turned off,
so technically there are 3 queues on the device, and name[4] should
correspond to the 3rd queue on the device.
So we use queue_idx as the queue index, which is increased only when the
queue exists.
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
---
drivers/virtio/virtio_pci_common.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c
index 465a6f5..d0584c0 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -285,7 +285,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
u16 msix_vec;
- int i, err, nvectors, allocated_vectors;
+ int i, err, nvectors, allocated_vectors, queue_idx = 0;
vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
if (!vp_dev->vqs)
@@ -321,7 +321,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
msix_vec = allocated_vectors++;
else
msix_vec = VP_MSIX_VQ_VECTOR;
- vqs[i] = vp_setup_vq(vdev, i, callbacks[i], names[i],
+ vqs[i] = vp_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
ctx ? ctx[i] : false,
msix_vec);
if (IS_ERR(vqs[i])) {
@@ -356,7 +356,7 @@ static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned nvqs,
const char * const names[], const bool *ctx)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- int i, err;
+ int i, err, queue_idx = 0;
vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
if (!vp_dev->vqs)
@@ -374,7 +374,7 @@ static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned nvqs,
vqs[i] = NULL;
continue;
}
- vqs[i] = vp_setup_vq(vdev, i, callbacks[i], names[i],
+ vqs[i] = vp_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
ctx ? ctx[i] : false,
VIRTIO_MSI_NO_VECTOR);
if (IS_ERR(vqs[i])) {
--
2.7.4
^ permalink raw reply related
* [PATCH v1 0/2] Virtio: fix some vq allocation issues
From: Wei Wang @ 2018-12-28 2:26 UTC (permalink / raw)
To: virtio-dev, linux-kernel, virtualization, kvm, mst, cohuck
Cc: dgilbert, pbonzini
Some vqs don't need to be allocated when the related feature bits are
disabled. Callers notice the vq allocation layer by setting the related
names[i] to be NULL.
This patch series fixes the find_vqs implementations to handle this case.
Wei Wang (2):
virtio_pci: use queue idx instead of array idx to set up the vq
virtio: don't allocate vqs when names[i] = NULL
drivers/misc/mic/vop/vop_main.c | 9 +++++++--
drivers/remoteproc/remoteproc_virtio.c | 9 +++++++--
drivers/s390/virtio/virtio_ccw.c | 12 +++++++++---
drivers/virtio/virtio_mmio.c | 9 +++++++--
drivers/virtio/virtio_pci_common.c | 8 ++++----
5 files changed, 34 insertions(+), 13 deletions(-)
--
2.7.4
^ permalink raw reply
* CFP WINSYS 2019 - Int.l Conf. on Wireless Networks and Mobile Systems (Prague/Czech Republic)
From: icete @ 2018-12-27 23:05 UTC (permalink / raw)
To: virtualization
SUBMISSION DEADLINE
International Conference on Wireless Networks and Mobile Systems
Submission Deadline: February 28, 2019
http://www.winsys.icete.org/
July 26 - 28, 2019
Prague, Czech Republic.
WINSYS is organized in 3 major tracks:
- Sensor Networks and Ad Hoc Communications
- Wireless and Mobile Technologies
- Mobile Software and Services
In Cooperation with: Photonics21 and EOS.
Proceedings will be submitted for indexation by: DBLP, Thomson Reuters, EI, SCOPUS, Semantic Scholar and Google Scholar.
A short list of presented papers will be selected so that revised and extended versions of these papers will be published by Springer.
All papers presented at the congress venue will also be available at the SCITEPRESS Digital Library (http://www.scitepress.org/DigitalLibrary/).
Should you have any question please don't hesitate contacting me.
Kind regards,
WINSYS Secretariat
Address: Av. D. Manuel I, 27A, 2º esq.
2910-595 Setubal, Portugal
Tel: +351 265 520 185
Fax: +351 265 520 186
Web: http://www.winsys.icete.org/
e-mail: winsys.secretariat@insticc.org
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply
* CFP SECRYPT 2019 - Int.l Conf. on Security and Cryptography (Prague/Czech Republic)
From: icete @ 2018-12-27 23:05 UTC (permalink / raw)
To: virtualization
SUBMISSION DEADLINE
International Conference on Security and Cryptography
Submission Deadline: February 28, 2019
http://www.secrypt.icete.org/
July 26 - 28, 2019
Prague, Czech Republic.
In Cooperation with: Photonics21 and EOS.
Proceedings will be submitted for indexation by: DBLP, Thomson Reuters, EI, SCOPUS, Semantic Scholar and Google Scholar.
A short list of presented papers will be selected so that revised and extended versions of these papers will be published by Springer.
All papers presented at the congress venue will also be available at the SCITEPRESS Digital Library (http://www.scitepress.org/DigitalLibrary/).
Should you have any question please don't hesitate contacting me.
Kind regards,
SECRYPT Secretariat
Address: Av. D. Manuel I, 27A, 2º esq.
2910-595 Setubal, Portugal
Tel: +351 265 520 185
Fax: +351 265 520 186
Web: http://www.secrypt.icete.org/
e-mail: secrypt.secretariat@insticc.org
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply
* CFP DCNET 2019 - Int.l Conf. on Data Communication Networking (Prague/Czech Republic)
From: icete @ 2018-12-27 23:05 UTC (permalink / raw)
To: virtualization
SUBMISSION DEADLINE
International Conference on Data Communication Networking
Submission Deadline: February 28, 2019
http://www.dcnet.icete.org/
July 26 - 28, 2019
Prague, Czech Republic.
In Cooperation with: Photonics21 and EOS.
Proceedings will be submitted for indexation by: DBLP, Thomson Reuters, EI, SCOPUS, Semantic Scholar and Google Scholar.
A short list of presented papers will be selected so that revised and extended versions of these papers will be published by Springer.
All papers presented at the congress venue will also be available at the SCITEPRESS Digital Library (http://www.scitepress.org/DigitalLibrary/).
Should you have any question please don't hesitate contacting me.
Kind regards,
DCNET Secretariat
Address: Av. D. Manuel I, 27A, 2º esq.
2910-595 Setubal, Portugal
Tel: +351 265 520 185
Fax: +351 265 520 186
Web: http://www.dcnet.icete.org/
e-mail: dcnet.secretariat@insticc.org
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply
* CFP ICETE 2019 - 16th Int.l Joint Conf. on e-Business and Telecommunications (Prague/Czech Republic)
From: icete @ 2018-12-27 23:05 UTC (permalink / raw)
To: virtualization
SUBMISSION DEADLINE
16th International Joint Conference on e-Business and Telecommunications
Submission Deadline: February 28, 2019
http://www.icete.org/
July 26 - 28, 2019
Prague, Czech Republic.
In Cooperation with: Photonics21 and EOS.
Proceedings will be submitted for indexation by: DBLP, Thomson Reuters, EI, SCOPUS, Semantic Scholar and Google Scholar.
A short list of presented papers will be selected so that revised and extended versions of these papers will be published by Springer.
All papers presented at the congress venue will also be available at the SCITEPRESS Digital Library (http://www.scitepress.org/DigitalLibrary/).
Should you have any question please don't hesitate contacting me.
Kind regards,
ICETE Secretariat
Address: Av. D. Manuel I, 27A, 2º esq.
2910-595 Setubal, Portugal
Tel: +351 265 520 185
Fax: +351 265 520 186
Web: http://www.icete.org/
e-mail: icete.secretariat@insticc.org
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply
page: next (older) | prev (newer) | latest
- recent:[subjects (threaded)|topics (new)|topics (active)]
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox