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Tsirkin" To: Bo Liu Cc: jasowang@redhat.com, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] virtio_ring: remove unnecessary to_vvq call Message-ID: <20220607023646-mutt-send-email-mst@kernel.org> References: <20220607005951.2221-1-liubo03@inspur.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220607005951.2221-1-liubo03@inspur.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 06, 2022 at 08:59:51PM -0400, Bo Liu wrote: > In many functions, the parameter passed in is "_vq", which still call > to_vvq() to get 'vq'. It can avoid unnecessary call of to_vvq() by directly > passing in the parameter "vq". > > Signed-off-by: Bo Liu What does the patch accomplish? Is the generated binary faster? smaller? > --- > drivers/virtio/virtio_ring.c | 100 ++++++++++++++--------------------- > 1 file changed, 41 insertions(+), 59 deletions(-) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index 13a7348cedff..f82db59fdbdc 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -648,9 +648,8 @@ static inline int virtqueue_add_split(struct virtqueue *_vq, > return -ENOMEM; > } > > -static bool virtqueue_kick_prepare_split(struct virtqueue *_vq) > +static bool virtqueue_kick_prepare_split(struct vring_virtqueue *vq) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > u16 new, old; > bool needs_kick; > > @@ -667,12 +666,12 @@ static bool virtqueue_kick_prepare_split(struct virtqueue *_vq) > LAST_ADD_TIME_INVALID(vq); > > if (vq->event) { > - needs_kick = vring_need_event(virtio16_to_cpu(_vq->vdev, > + needs_kick = vring_need_event(virtio16_to_cpu(vq->vq.vdev, > vring_avail_event(&vq->split.vring)), > new, old); > } else { > needs_kick = !(vq->split.vring.used->flags & > - cpu_to_virtio16(_vq->vdev, > + cpu_to_virtio16(vq->vq.vdev, > VRING_USED_F_NO_NOTIFY)); > } > END_USE(vq); > @@ -735,11 +734,10 @@ static inline bool more_used_split(const struct vring_virtqueue *vq) > vq->split.vring.used->idx); > } > > -static void *virtqueue_get_buf_ctx_split(struct virtqueue *_vq, > +static void *virtqueue_get_buf_ctx_split(struct vring_virtqueue *vq, > unsigned int *len, > void **ctx) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > void *ret; > unsigned int i; > u16 last_used; > @@ -761,9 +759,9 @@ static void *virtqueue_get_buf_ctx_split(struct virtqueue *_vq, > virtio_rmb(vq->weak_barriers); > > last_used = (vq->last_used_idx & (vq->split.vring.num - 1)); > - i = virtio32_to_cpu(_vq->vdev, > + i = virtio32_to_cpu(vq->vq.vdev, > vq->split.vring.used->ring[last_used].id); > - *len = virtio32_to_cpu(_vq->vdev, > + *len = virtio32_to_cpu(vq->vq.vdev, > vq->split.vring.used->ring[last_used].len); > > if (unlikely(i >= vq->split.vring.num)) { > @@ -785,7 +783,7 @@ static void *virtqueue_get_buf_ctx_split(struct virtqueue *_vq, > if (!(vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) > virtio_store_mb(vq->weak_barriers, > &vring_used_event(&vq->split.vring), > - cpu_to_virtio16(_vq->vdev, vq->last_used_idx)); > + cpu_to_virtio16(vq->vq.vdev, vq->last_used_idx)); > > LAST_ADD_TIME_INVALID(vq); > > @@ -793,10 +791,8 @@ static void *virtqueue_get_buf_ctx_split(struct virtqueue *_vq, > return ret; > } > > -static void virtqueue_disable_cb_split(struct virtqueue *_vq) > +static void virtqueue_disable_cb_split(struct vring_virtqueue *vq) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > - > if (!(vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) { > vq->split.avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT; > if (vq->event) > @@ -804,14 +800,13 @@ static void virtqueue_disable_cb_split(struct virtqueue *_vq) > vring_used_event(&vq->split.vring) = 0x0; > else > vq->split.vring.avail->flags = > - cpu_to_virtio16(_vq->vdev, > + cpu_to_virtio16(vq->vq.vdev, > vq->split.avail_flags_shadow); > } > } > > -static unsigned int virtqueue_enable_cb_prepare_split(struct virtqueue *_vq) > +static unsigned int virtqueue_enable_cb_prepare_split(struct vring_virtqueue *vq) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > u16 last_used_idx; > > START_USE(vq); > @@ -825,26 +820,23 @@ static unsigned int virtqueue_enable_cb_prepare_split(struct virtqueue *_vq) > vq->split.avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT; > if (!vq->event) > vq->split.vring.avail->flags = > - cpu_to_virtio16(_vq->vdev, > + cpu_to_virtio16(vq->vq.vdev, > vq->split.avail_flags_shadow); > } > - vring_used_event(&vq->split.vring) = cpu_to_virtio16(_vq->vdev, > + vring_used_event(&vq->split.vring) = cpu_to_virtio16(vq->vq.vdev, > last_used_idx = vq->last_used_idx); > END_USE(vq); > return last_used_idx; > } > > -static bool virtqueue_poll_split(struct virtqueue *_vq, unsigned int last_used_idx) > +static bool virtqueue_poll_split(struct vring_virtqueue *vq, unsigned int last_used_idx) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > - > - return (u16)last_used_idx != virtio16_to_cpu(_vq->vdev, > + return (u16)last_used_idx != virtio16_to_cpu(vq->vq.vdev, > vq->split.vring.used->idx); > } > > -static bool virtqueue_enable_cb_delayed_split(struct virtqueue *_vq) > +static bool virtqueue_enable_cb_delayed_split(struct vring_virtqueue *vq) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > u16 bufs; > > START_USE(vq); > @@ -858,7 +850,7 @@ static bool virtqueue_enable_cb_delayed_split(struct virtqueue *_vq) > vq->split.avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT; > if (!vq->event) > vq->split.vring.avail->flags = > - cpu_to_virtio16(_vq->vdev, > + cpu_to_virtio16(vq->vq.vdev, > vq->split.avail_flags_shadow); > } > /* TODO: tune this threshold */ > @@ -866,9 +858,9 @@ static bool virtqueue_enable_cb_delayed_split(struct virtqueue *_vq) > > virtio_store_mb(vq->weak_barriers, > &vring_used_event(&vq->split.vring), > - cpu_to_virtio16(_vq->vdev, vq->last_used_idx + bufs)); > + cpu_to_virtio16(vq->vq.vdev, vq->last_used_idx + bufs)); > > - if (unlikely((u16)(virtio16_to_cpu(_vq->vdev, vq->split.vring.used->idx) > + if (unlikely((u16)(virtio16_to_cpu(vq->vq.vdev, vq->split.vring.used->idx) > - vq->last_used_idx) > bufs)) { > END_USE(vq); > return false; > @@ -878,9 +870,8 @@ static bool virtqueue_enable_cb_delayed_split(struct virtqueue *_vq) > return true; > } > > -static void *virtqueue_detach_unused_buf_split(struct virtqueue *_vq) > +static void *virtqueue_detach_unused_buf_split(struct vring_virtqueue *vq) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > unsigned int i; > void *buf; > > @@ -893,7 +884,7 @@ static void *virtqueue_detach_unused_buf_split(struct virtqueue *_vq) > buf = vq->split.desc_state[i].data; > detach_buf_split(vq, i, NULL); > vq->split.avail_idx_shadow--; > - vq->split.vring.avail->idx = cpu_to_virtio16(_vq->vdev, > + vq->split.vring.avail->idx = cpu_to_virtio16(vq->vq.vdev, > vq->split.avail_idx_shadow); > END_USE(vq); > return buf; > @@ -1296,9 +1287,8 @@ static inline int virtqueue_add_packed(struct virtqueue *_vq, > return -EIO; > } > > -static bool virtqueue_kick_prepare_packed(struct virtqueue *_vq) > +static bool virtqueue_kick_prepare_packed(struct vring_virtqueue *vq) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > u16 new, old, off_wrap, flags, wrap_counter, event_idx; > bool needs_kick; > union { > @@ -1410,11 +1400,10 @@ static inline bool more_used_packed(const struct vring_virtqueue *vq) > vq->packed.used_wrap_counter); > } > > -static void *virtqueue_get_buf_ctx_packed(struct virtqueue *_vq, > +static void *virtqueue_get_buf_ctx_packed(struct vring_virtqueue *vq, > unsigned int *len, > void **ctx) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > u16 last_used, id; > void *ret; > > @@ -1475,10 +1464,8 @@ static void *virtqueue_get_buf_ctx_packed(struct virtqueue *_vq, > return ret; > } > > -static void virtqueue_disable_cb_packed(struct virtqueue *_vq) > +static void virtqueue_disable_cb_packed(struct vring_virtqueue *vq) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > - > if (vq->packed.event_flags_shadow != VRING_PACKED_EVENT_FLAG_DISABLE) { > vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE; > vq->packed.vring.driver->flags = > @@ -1486,10 +1473,8 @@ static void virtqueue_disable_cb_packed(struct virtqueue *_vq) > } > } > > -static unsigned int virtqueue_enable_cb_prepare_packed(struct virtqueue *_vq) > +static unsigned int virtqueue_enable_cb_prepare_packed(struct vring_virtqueue *vq) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > - > START_USE(vq); > > /* > @@ -1522,9 +1507,8 @@ static unsigned int virtqueue_enable_cb_prepare_packed(struct virtqueue *_vq) > VRING_PACKED_EVENT_F_WRAP_CTR); > } > > -static bool virtqueue_poll_packed(struct virtqueue *_vq, u16 off_wrap) > +static bool virtqueue_poll_packed(struct vring_virtqueue *vq, u16 off_wrap) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > bool wrap_counter; > u16 used_idx; > > @@ -1534,9 +1518,8 @@ static bool virtqueue_poll_packed(struct virtqueue *_vq, u16 off_wrap) > return is_used_desc_packed(vq, used_idx, wrap_counter); > } > > -static bool virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) > +static bool virtqueue_enable_cb_delayed_packed(struct vring_virtqueue *vq) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > u16 used_idx, wrap_counter; > u16 bufs; > > @@ -1593,9 +1576,8 @@ static bool virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) > return true; > } > > -static void *virtqueue_detach_unused_buf_packed(struct virtqueue *_vq) > +static void *virtqueue_detach_unused_buf_packed(struct vring_virtqueue *vq) > { > - struct vring_virtqueue *vq = to_vvq(_vq); > unsigned int i; > void *buf; > > @@ -1906,8 +1888,8 @@ bool virtqueue_kick_prepare(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > - return vq->packed_ring ? virtqueue_kick_prepare_packed(_vq) : > - virtqueue_kick_prepare_split(_vq); > + return vq->packed_ring ? virtqueue_kick_prepare_packed(vq) : > + virtqueue_kick_prepare_split(vq); > } > EXPORT_SYMBOL_GPL(virtqueue_kick_prepare); > > @@ -1977,8 +1959,8 @@ void *virtqueue_get_buf_ctx(struct virtqueue *_vq, unsigned int *len, > { > struct vring_virtqueue *vq = to_vvq(_vq); > > - return vq->packed_ring ? virtqueue_get_buf_ctx_packed(_vq, len, ctx) : > - virtqueue_get_buf_ctx_split(_vq, len, ctx); > + return vq->packed_ring ? virtqueue_get_buf_ctx_packed(vq, len, ctx) : > + virtqueue_get_buf_ctx_split(vq, len, ctx); > } > EXPORT_SYMBOL_GPL(virtqueue_get_buf_ctx); > > @@ -2007,9 +1989,9 @@ void virtqueue_disable_cb(struct virtqueue *_vq) > return; > > if (vq->packed_ring) > - virtqueue_disable_cb_packed(_vq); > + virtqueue_disable_cb_packed(vq); > else > - virtqueue_disable_cb_split(_vq); > + virtqueue_disable_cb_split(vq); > } > EXPORT_SYMBOL_GPL(virtqueue_disable_cb); > > @@ -2032,8 +2014,8 @@ unsigned int virtqueue_enable_cb_prepare(struct virtqueue *_vq) > if (vq->event_triggered) > vq->event_triggered = false; > > - return vq->packed_ring ? virtqueue_enable_cb_prepare_packed(_vq) : > - virtqueue_enable_cb_prepare_split(_vq); > + return vq->packed_ring ? virtqueue_enable_cb_prepare_packed(vq) : > + virtqueue_enable_cb_prepare_split(vq); > } > EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare); > > @@ -2054,8 +2036,8 @@ bool virtqueue_poll(struct virtqueue *_vq, unsigned int last_used_idx) > return false; > > virtio_mb(vq->weak_barriers); > - return vq->packed_ring ? virtqueue_poll_packed(_vq, last_used_idx) : > - virtqueue_poll_split(_vq, last_used_idx); > + return vq->packed_ring ? virtqueue_poll_packed(vq, last_used_idx) : > + virtqueue_poll_split(vq, last_used_idx); > } > EXPORT_SYMBOL_GPL(virtqueue_poll); > > @@ -2098,8 +2080,8 @@ bool virtqueue_enable_cb_delayed(struct virtqueue *_vq) > if (vq->event_triggered) > vq->event_triggered = false; > > - return vq->packed_ring ? virtqueue_enable_cb_delayed_packed(_vq) : > - virtqueue_enable_cb_delayed_split(_vq); > + return vq->packed_ring ? virtqueue_enable_cb_delayed_packed(vq) : > + virtqueue_enable_cb_delayed_split(vq); > } > EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed); > > @@ -2115,8 +2097,8 @@ void *virtqueue_detach_unused_buf(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > - return vq->packed_ring ? virtqueue_detach_unused_buf_packed(_vq) : > - virtqueue_detach_unused_buf_split(_vq); > + return vq->packed_ring ? virtqueue_detach_unused_buf_packed(vq) : > + virtqueue_detach_unused_buf_split(vq); > } > EXPORT_SYMBOL_GPL(virtqueue_detach_unused_buf); > > -- > 2.27.0