search for: is_used_desc_pack

...) { OK so trying to unpack the scenario. First you patch only affects code running when EVENT_IDX is off, so legal values for flags are enable and disable. Next point, this calculates the index at which we are going to look for the flags to change, in other words it affects the line if (is_used_desc_packed(vq, used_idx, wrap_counter)) { below. Without your patch, we simply look at the next descriptor. This is exactly what the spec says we should do: Writes of device and driver descriptors can generally be reordered, but each side (driver and device) are only required to poll (or test) a single...

...= vq->packed.used_wrap_counter; > } > > if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) { > @@ -1518,7 +1515,9 @@ static bool virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) > */ > virtio_mb(vq->weak_barriers); > > - if (is_used_desc_packed(vq, used_idx, wrap_counter)) { > + if (is_used_desc_packed(vq, > + vq->last_used_idx, > + vq->packed.used_wrap_counter)) { > END_USE(vq); > return false; > } > -- > 2.17.1

...= vq->last_used_idx; - wrap_counter = vq->packed.used_wrap_counter; } if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) { @@ -1518,7 +1515,9 @@ static bool virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) */ virtio_mb(vq->weak_barriers); - if (is_used_desc_packed(vq, used_idx, wrap_counter)) { + if (is_used_desc_packed(vq, + vq->last_used_idx, + vq->packed.used_wrap_counter)) { END_USE(vq); return false; } -- MST

...FLAG_DISABLE) >>>> { >>>>> @@ -1518,7 +1515,9 @@ static bool >>>> virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) >>>>> */ >>>>> virtio_mb(vq->weak_barriers); >>>>> >>>>> - if (is_used_desc_packed(vq, used_idx, wrap_counter)) { >>>>> + if (is_used_desc_packed(vq, >>>>> + vq->last_used_idx, >>>>> + vq->packed.used_wrap_counter)) { >>>>> END_USE(vq); >>>>> return false; >>>>>...

...>packed.used_wrap_counter; > } > > if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) { > @@ -1518,7 +1515,9 @@ static bool virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) > */ > virtio_mb(vq->weak_barriers); > > - if (is_used_desc_packed(vq, used_idx, wrap_counter)) { > + if (is_used_desc_packed(vq, > + vq->last_used_idx, > + vq->packed.used_wrap_counter)) { > END_USE(vq); > return false; > } Hi Marvin: Two questions: 1) Do we support IN_ORDER in kernel driver? 2) Should we check IN_O...

...f (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) >> { >>> @@ -1518,7 +1515,9 @@ static bool >> virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) >>> */ >>> virtio_mb(vq->weak_barriers); >>> >>> - if (is_used_desc_packed(vq, used_idx, wrap_counter)) { >>> + if (is_used_desc_packed(vq, >>> + vq->last_used_idx, >>> + vq->packed.used_wrap_counter)) { >>> END_USE(vq); >>> return false; >>> } >> >> Hi Marvin: >> >>...

...= vq->packed.used_wrap_counter; > } > > if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) { > @@ -1518,7 +1515,9 @@ static bool virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) > */ > virtio_mb(vq->weak_barriers); > > - if (is_used_desc_packed(vq, used_idx, wrap_counter)) { > + if (is_used_desc_packed(vq, > + vq->last_used_idx, > + vq->packed.used_wrap_counter)) { > END_USE(vq); > return false; > } > -- > 2.17.1

....len; + for (i = 0; i < len / sizeof(struct vring_packed_desc); + i++) + vring_unmap_desc_packed(vq, &desc[i]); + } + kfree(desc); + vq->desc_state_packed[id].indir_desc = NULL; + } else if (ctx) { + *ctx = vq->desc_state_packed[id].indir_desc; + } +} + +static inline bool is_used_desc_packed(const struct vring_virtqueue *vq, + u16 idx, bool used_wrap_counter) +{ + u16 flags; + bool avail, used; + + flags = virtio16_to_cpu(vq->vq.vdev, + vq->vring_packed.desc[idx].flags); + avail = !!(flags & VRING_DESC_F_AVAIL); + used = !!(flags & VRING_DESC_F_USED); + + r...

...packed_desc); > + i++) > + vring_unmap_desc_packed(vq, &desc[i]); > + } > + kfree(desc); > + vq->desc_state_packed[id].indir_desc = NULL; > + } else if (ctx) { > + *ctx = vq->desc_state_packed[id].indir_desc; > + } > +} > + > +static inline bool is_used_desc_packed(const struct vring_virtqueue *vq, > + u16 idx, bool used_wrap_counter) > +{ > + u16 flags; > + bool avail, used; > + > + flags = virtio16_to_cpu(vq->vq.vdev, > + vq->vring_packed.desc[idx].flags); > + avail = !!(flags & VRING_DESC_F_AVAIL); > + us...

...D_EVENT_F_WRAP_CTR; - event_idx = off_wrap & ~(1 << VRING_PACKED_EVENT_F_WRAP_CTR); + event_idx = off_wrap & ~BIT(VRING_PACKED_EVENT_F_WRAP_CTR); if (wrap_counter != vq->packed.avail_wrap_counter) event_idx -= vq->packed.vring.num; @@ -1321,8 +1338,8 @@ static inline bool is_used_desc_packed(const struct vring_virtqueue *vq, u16 flags; flags = le16_to_cpu(vq->packed.vring.desc[idx].flags); - avail = !!(flags & (1 << VRING_PACKED_DESC_F_AVAIL)); - used = !!(flags & (1 << VRING_PACKED_DESC_F_USED)); + avail = !!(flags & BIT(VRING_PACKED_DESC_F_AVAIL));...

..._barriers); > } > > - if (more_used_packed(vq)) { > + /* We need to update event suppression structure first > + * before re-checking for more used buffers. */ > + virtio_mb(vq->weak_barriers); > + mb is expensive. We should not do it if we changed nothing. > + if (is_used_desc_packed(vq, used_idx, wrap_counter)) { > END_USE(vq); > return false; > } > -- > 2.18.0

...packed_desc); > + i++) > + vring_unmap_desc_packed(vq, &desc[i]); > + } > + kfree(desc); > + vq->desc_state_packed[id].indir_desc = NULL; > + } else if (ctx) { > + *ctx = vq->desc_state_packed[id].indir_desc; > + } > +} > + > +static inline bool is_used_desc_packed(const struct vring_virtqueue *vq, > + u16 idx, bool used_wrap_counter) > +{ > + u16 flags; > + bool avail, used; > + > + flags = virtio16_to_cpu(vq->vq.vdev, > + vq->vring_packed.desc[idx].flags); > + avail = !!(flags & VRING_DESC_F_AVAIL); > + us...

...packed_desc); > + i++) > + vring_unmap_desc_packed(vq, &desc[i]); > + } > + kfree(desc); > + vq->desc_state_packed[id].indir_desc = NULL; > + } else if (ctx) { > + *ctx = vq->desc_state_packed[id].indir_desc; > + } > +} > + > +static inline bool is_used_desc_packed(const struct vring_virtqueue *vq, > + u16 idx, bool used_wrap_counter) > +{ > + u16 flags; > + bool avail, used; > + > + flags = virtio16_to_cpu(vq->vq.vdev, > + vq->vring_packed.desc[idx].flags); > + avail = !!(flags & VRING_DESC_F_AVAIL); > + us...

...to enable interrupts first before re-checking - * for more used buffers. */ - virtio_mb(vq->weak_barriers); } - if (more_used_packed(vq)) { + /* We need to update event suppression structure first + * before re-checking for more used buffers. */ + virtio_mb(vq->weak_barriers); + + if (is_used_desc_packed(vq, used_idx, wrap_counter)) { END_USE(vq); return false; } -- 2.18.0

...to enable interrupts first before re-checking - * for more used buffers. */ - virtio_mb(vq->weak_barriers); } - if (more_used_packed(vq)) { + /* We need to update event suppression structure first + * before re-checking for more used buffers. */ + virtio_mb(vq->weak_barriers); + + if (is_used_desc_packed(vq, used_idx, wrap_counter)) { END_USE(vq); return false; } -- 2.18.0

Hello everyone, This patch set implements packed ring support in virtio driver. Some functional tests have been done with Jason's packed ring implementation in vhost: https://lkml.org/lkml/2018/7/3/33 Both of ping and netperf worked as expected. v1 -> v2: - Use READ_ONCE() to read event off_wrap and flags together (Jason); - Add comments related to ccw (Jason); RFC (v6) -> v1: -

Hello everyone, This patch set implements packed ring support in virtio driver. Some functional tests have been done with Jason's packed ring implementation in vhost: https://lkml.org/lkml/2018/7/3/33 Both of ping and netperf worked as expected. v1 -> v2: - Use READ_ONCE() to read event off_wrap and flags together (Jason); - Add comments related to ccw (Jason); RFC (v6) -> v1: -

This is a follow up of the discussion in this thread: https://patchwork.ozlabs.org/patch/1001015/#2042353 Tiwei Bie (3): virtio_ring: define flags as shifts consistently virtio_ring: add VIRTIO_RING_NO_LEGACY virtio_ring: use new vring flags drivers/virtio/virtio_ring.c | 100 ++++++++++++++++++------------- include/uapi/linux/virtio_ring.h | 61 +++++++++++++------ 2 files changed,

This is a follow up of the discussion in this thread: https://patchwork.ozlabs.org/patch/1001015/#2042353 Tiwei Bie (3): virtio_ring: define flags as shifts consistently virtio_ring: add VIRTIO_RING_NO_LEGACY virtio_ring: use new vring flags drivers/virtio/virtio_ring.c | 100 ++++++++++++++++++------------- include/uapi/linux/virtio_ring.h | 61 +++++++++++++------ 2 files changed,

Hello everyone, This patch set implements packed ring support in virtio driver. Some functional tests have been done with Jason's packed ring implementation in vhost: https://lkml.org/lkml/2018/7/3/33 Both of ping and netperf worked as expected. RFC (v6) -> v1: - Avoid extra virtio_wmb() in virtqueue_enable_cb_delayed_packed() when event idx is off (Jason); - Fix bufs calculation in