| Message ID | 20250302143259.1221569-7-lulu@redhat.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | vhost: Add support of kthread API | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Sun, Mar 02, 2025 at 10:32:08PM +0800, Cindy Lu wrote: >Add a new UAPI to configure the vhost device to use the kthread mode >The userspace application can use IOCTL VHOST_FORK_FROM_OWNER >to choose between owner and kthread mode if necessary >This setting must be applied before VHOST_SET_OWNER, as the worker >will be created in the VHOST_SET_OWNER function > >Signed-off-by: Cindy Lu <lulu@redhat.com> >--- > drivers/vhost/vhost.c | 22 ++++++++++++++++++++-- > include/uapi/linux/vhost.h | 15 +++++++++++++++ > 2 files changed, 35 insertions(+), 2 deletions(-) > >diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c >index be97028a8baf..ff930c2e5b78 100644 >--- a/drivers/vhost/vhost.c >+++ b/drivers/vhost/vhost.c >@@ -1134,7 +1134,7 @@ void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_iotlb *umem) > int i; > > vhost_dev_cleanup(dev); >- >+ dev->inherit_owner = true; > dev->umem = umem; > /* We don't need VQ locks below since vhost_dev_cleanup makes sure > * VQs aren't running. >@@ -2287,7 +2287,25 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) > r = vhost_dev_set_owner(d); > goto done; > } >- >+ if (ioctl == VHOST_FORK_FROM_OWNER) { >+ u8 inherit_owner; >+ /*inherit_owner can only be modified before owner is set*/ >+ if (vhost_dev_has_owner(d)) { >+ r = -EBUSY; >+ goto done; >+ } >+ if (copy_from_user(&inherit_owner, argp, sizeof(u8))) { >+ r = -EFAULT; >+ goto done; >+ } >+ if (inherit_owner > 1) { >+ r = -EINVAL; >+ goto done; >+ } >+ d->inherit_owner = (bool)inherit_owner; >+ r = 0; >+ goto done; >+ } > /* You must be the owner to do anything else */ > r = vhost_dev_check_owner(d); > if (r) >diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h >index b95dd84eef2d..547b4fa4c3bd 100644 >--- a/include/uapi/linux/vhost.h >+++ b/include/uapi/linux/vhost.h >@@ -235,4 +235,19 @@ > */ > #define VHOST_VDPA_GET_VRING_SIZE _IOWR(VHOST_VIRTIO, 0x82, \ > struct vhost_vring_state) >+ >+/** >+ * VHOST_FORK_FROM_OWNER - Set the inherit_owner flag for the vhost device Should we mention that this IOCTL must be called before VHOST_SET_OWNER? >+ * >+ * @param inherit_owner: An 8-bit value that determines the vhost thread mode >+ * >+ * When inherit_owner is set to 1(default value): >+ * - Vhost will create tasks similar to processes forked from the owner, >+ * inheriting all of the owner's attributes.. ^ nit: there 2 points here >+ * >+ * When inherit_owner is set to 0: >+ * - Vhost will create tasks as kernel thread >+ */ >+#define VHOST_FORK_FROM_OWNER _IOW(VHOST_VIRTIO, 0x83, __u8) >+ > #endif >-- >2.45.0 >
On Mon, Mar 3, 2025 at 4:58 PM Stefano Garzarella <sgarzare@redhat.com> wrote: > > On Sun, Mar 02, 2025 at 10:32:08PM +0800, Cindy Lu wrote: > >Add a new UAPI to configure the vhost device to use the kthread mode > >The userspace application can use IOCTL VHOST_FORK_FROM_OWNER > >to choose between owner and kthread mode if necessary > >This setting must be applied before VHOST_SET_OWNER, as the worker > >will be created in the VHOST_SET_OWNER function > > > >Signed-off-by: Cindy Lu <lulu@redhat.com> > >--- > > drivers/vhost/vhost.c | 22 ++++++++++++++++++++-- > > include/uapi/linux/vhost.h | 15 +++++++++++++++ > > 2 files changed, 35 insertions(+), 2 deletions(-) > > > >diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > >index be97028a8baf..ff930c2e5b78 100644 > >--- a/drivers/vhost/vhost.c > >+++ b/drivers/vhost/vhost.c > >@@ -1134,7 +1134,7 @@ void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_iotlb *umem) > > int i; > > > > vhost_dev_cleanup(dev); > >- > >+ dev->inherit_owner = true; > > dev->umem = umem; > > /* We don't need VQ locks below since vhost_dev_cleanup makes sure > > * VQs aren't running. > >@@ -2287,7 +2287,25 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) > > r = vhost_dev_set_owner(d); > > goto done; > > } > >- > >+ if (ioctl == VHOST_FORK_FROM_OWNER) { > >+ u8 inherit_owner; > >+ /*inherit_owner can only be modified before owner is set*/ > >+ if (vhost_dev_has_owner(d)) { > >+ r = -EBUSY; > >+ goto done; > >+ } > >+ if (copy_from_user(&inherit_owner, argp, sizeof(u8))) { > >+ r = -EFAULT; > >+ goto done; > >+ } > >+ if (inherit_owner > 1) { > >+ r = -EINVAL; > >+ goto done; > >+ } > >+ d->inherit_owner = (bool)inherit_owner; > >+ r = 0; > >+ goto done; > >+ } > > /* You must be the owner to do anything else */ > > r = vhost_dev_check_owner(d); > > if (r) > >diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h > >index b95dd84eef2d..547b4fa4c3bd 100644 > >--- a/include/uapi/linux/vhost.h > >+++ b/include/uapi/linux/vhost.h > >@@ -235,4 +235,19 @@ > > */ > > #define VHOST_VDPA_GET_VRING_SIZE _IOWR(VHOST_VIRTIO, 0x82, \ > > struct vhost_vring_state) > >+ > >+/** > >+ * VHOST_FORK_FROM_OWNER - Set the inherit_owner flag for the vhost device > > Should we mention that this IOCTL must be called before VHOST_SET_OWNER? > > >+ * > >+ * @param inherit_owner: An 8-bit value that determines the vhost thread mode > >+ * > >+ * When inherit_owner is set to 1(default value): > >+ * - Vhost will create tasks similar to processes forked from the owner, > >+ * inheriting all of the owner's attributes.. > ^ > nit: there 2 points here > Thanks Stefano, I will change this Thanks cindy > >+ * > >+ * When inherit_owner is set to 0: > >+ * - Vhost will create tasks as kernel thread > >+ */ > >+#define VHOST_FORK_FROM_OWNER _IOW(VHOST_VIRTIO, 0x83, __u8) > >+ > > #endif > >-- > >2.45.0 > > >
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index be97028a8baf..ff930c2e5b78 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1134,7 +1134,7 @@ void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_iotlb *umem) int i; vhost_dev_cleanup(dev); - + dev->inherit_owner = true; dev->umem = umem; /* We don't need VQ locks below since vhost_dev_cleanup makes sure * VQs aren't running. @@ -2287,7 +2287,25 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) r = vhost_dev_set_owner(d); goto done; } - + if (ioctl == VHOST_FORK_FROM_OWNER) { + u8 inherit_owner; + /*inherit_owner can only be modified before owner is set*/ + if (vhost_dev_has_owner(d)) { + r = -EBUSY; + goto done; + } + if (copy_from_user(&inherit_owner, argp, sizeof(u8))) { + r = -EFAULT; + goto done; + } + if (inherit_owner > 1) { + r = -EINVAL; + goto done; + } + d->inherit_owner = (bool)inherit_owner; + r = 0; + goto done; + } /* You must be the owner to do anything else */ r = vhost_dev_check_owner(d); if (r) diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h index b95dd84eef2d..547b4fa4c3bd 100644 --- a/include/uapi/linux/vhost.h +++ b/include/uapi/linux/vhost.h @@ -235,4 +235,19 @@ */ #define VHOST_VDPA_GET_VRING_SIZE _IOWR(VHOST_VIRTIO, 0x82, \ struct vhost_vring_state) + +/** + * VHOST_FORK_FROM_OWNER - Set the inherit_owner flag for the vhost device + * + * @param inherit_owner: An 8-bit value that determines the vhost thread mode + * + * When inherit_owner is set to 1(default value): + * - Vhost will create tasks similar to processes forked from the owner, + * inheriting all of the owner's attributes.. + * + * When inherit_owner is set to 0: + * - Vhost will create tasks as kernel thread + */ +#define VHOST_FORK_FROM_OWNER _IOW(VHOST_VIRTIO, 0x83, __u8) + #endif
Add a new UAPI to configure the vhost device to use the kthread mode The userspace application can use IOCTL VHOST_FORK_FROM_OWNER to choose between owner and kthread mode if necessary This setting must be applied before VHOST_SET_OWNER, as the worker will be created in the VHOST_SET_OWNER function Signed-off-by: Cindy Lu <lulu@redhat.com> --- drivers/vhost/vhost.c | 22 ++++++++++++++++++++-- include/uapi/linux/vhost.h | 15 +++++++++++++++ 2 files changed, 35 insertions(+), 2 deletions(-)