| Message ID | 20210520141305.355961-3-stefanha@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | virtio_blk: blk-mq io_poll support | expand |
在 2021/5/20 下午10:13, Stefan Hajnoczi 写道: > struct virtio_blk_vq is accessed in many places. Introduce "vbq" local > variables to avoid repeating vblk->vqs[qid] throughout the code. The > patches that follow will add more accesses, making the payoff even > greater. > > virtio_commit_rqs() calls the local variable "vq", which is easily > confused with struct virtqueue. Rename to "vbq" for clarity. > > Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> > --- > drivers/block/virtio_blk.c | 34 +++++++++++++++++----------------- > 1 file changed, 17 insertions(+), 17 deletions(-) > > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c > index b9fa3ef5b57c..fc0fb1dcd399 100644 > --- a/drivers/block/virtio_blk.c > +++ b/drivers/block/virtio_blk.c > @@ -174,16 +174,16 @@ static inline void virtblk_request_done(struct request *req) > static void virtblk_done(struct virtqueue *vq) > { > struct virtio_blk *vblk = vq->vdev->priv; > + struct virtio_blk_vq *vbq = &vblk->vqs[vq->index]; > bool req_done = false; > - int qid = vq->index; > struct virtblk_req *vbr; > unsigned long flags; > unsigned int len; > > - spin_lock_irqsave(&vblk->vqs[qid].lock, flags); > + spin_lock_irqsave(&vbq->lock, flags); > do { > virtqueue_disable_cb(vq); > - while ((vbr = virtqueue_get_buf(vblk->vqs[qid].vq, &len)) != NULL) { > + while ((vbr = virtqueue_get_buf(vq, &len)) != NULL) { > struct request *req = blk_mq_rq_from_pdu(vbr); > > if (likely(!blk_should_fake_timeout(req->q))) > @@ -197,32 +197,32 @@ static void virtblk_done(struct virtqueue *vq) > /* In case queue is stopped waiting for more buffers. */ > if (req_done) > blk_mq_start_stopped_hw_queues(vblk->disk->queue, true); > - spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); > + spin_unlock_irqrestore(&vbq->lock, flags); > } > > static void virtio_commit_rqs(struct blk_mq_hw_ctx *hctx) > { > struct virtio_blk *vblk = hctx->queue->queuedata; > - struct virtio_blk_vq *vq = &vblk->vqs[hctx->queue_num]; > + struct virtio_blk_vq *vbq = &vblk->vqs[hctx->queue_num]; > bool kick; > > - spin_lock_irq(&vq->lock); > - kick = virtqueue_kick_prepare(vq->vq); > - spin_unlock_irq(&vq->lock); > + spin_lock_irq(&vbq->lock); > + kick = virtqueue_kick_prepare(vbq->vq); > + spin_unlock_irq(&vbq->lock); > > if (kick) > - virtqueue_notify(vq->vq); > + virtqueue_notify(vbq->vq); > } > > static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx, > const struct blk_mq_queue_data *bd) > { > struct virtio_blk *vblk = hctx->queue->queuedata; > + struct virtio_blk_vq *vbq = &vblk->vqs[hctx->queue_num]; > struct request *req = bd->rq; > struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); > unsigned long flags; > unsigned int num; > - int qid = hctx->queue_num; > int err; > bool notify = false; > bool unmap = false; > @@ -274,16 +274,16 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx, > vbr->out_hdr.type |= cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_IN); > } > > - spin_lock_irqsave(&vblk->vqs[qid].lock, flags); > - err = virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num); > + spin_lock_irqsave(&vbq->lock, flags); > + err = virtblk_add_req(vbq->vq, vbr, vbr->sg, num); > if (err) { > - virtqueue_kick(vblk->vqs[qid].vq); > + virtqueue_kick(vbq->vq); > /* Don't stop the queue if -ENOMEM: we may have failed to > * bounce the buffer due to global resource outage. > */ > if (err == -ENOSPC) > blk_mq_stop_hw_queue(hctx); > - spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); > + spin_unlock_irqrestore(&vbq->lock, flags); > switch (err) { > case -ENOSPC: > return BLK_STS_DEV_RESOURCE; > @@ -294,12 +294,12 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx, > } > } > > - if (bd->last && virtqueue_kick_prepare(vblk->vqs[qid].vq)) > + if (bd->last && virtqueue_kick_prepare(vbq->vq)) > notify = true; > - spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); > + spin_unlock_irqrestore(&vbq->lock, flags); > > if (notify) > - virtqueue_notify(vblk->vqs[qid].vq); > + virtqueue_notify(vbq->vq); > return BLK_STS_OK; > } >
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index b9fa3ef5b57c..fc0fb1dcd399 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -174,16 +174,16 @@ static inline void virtblk_request_done(struct request *req) static void virtblk_done(struct virtqueue *vq) { struct virtio_blk *vblk = vq->vdev->priv; + struct virtio_blk_vq *vbq = &vblk->vqs[vq->index]; bool req_done = false; - int qid = vq->index; struct virtblk_req *vbr; unsigned long flags; unsigned int len; - spin_lock_irqsave(&vblk->vqs[qid].lock, flags); + spin_lock_irqsave(&vbq->lock, flags); do { virtqueue_disable_cb(vq); - while ((vbr = virtqueue_get_buf(vblk->vqs[qid].vq, &len)) != NULL) { + while ((vbr = virtqueue_get_buf(vq, &len)) != NULL) { struct request *req = blk_mq_rq_from_pdu(vbr); if (likely(!blk_should_fake_timeout(req->q))) @@ -197,32 +197,32 @@ static void virtblk_done(struct virtqueue *vq) /* In case queue is stopped waiting for more buffers. */ if (req_done) blk_mq_start_stopped_hw_queues(vblk->disk->queue, true); - spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); + spin_unlock_irqrestore(&vbq->lock, flags); } static void virtio_commit_rqs(struct blk_mq_hw_ctx *hctx) { struct virtio_blk *vblk = hctx->queue->queuedata; - struct virtio_blk_vq *vq = &vblk->vqs[hctx->queue_num]; + struct virtio_blk_vq *vbq = &vblk->vqs[hctx->queue_num]; bool kick; - spin_lock_irq(&vq->lock); - kick = virtqueue_kick_prepare(vq->vq); - spin_unlock_irq(&vq->lock); + spin_lock_irq(&vbq->lock); + kick = virtqueue_kick_prepare(vbq->vq); + spin_unlock_irq(&vbq->lock); if (kick) - virtqueue_notify(vq->vq); + virtqueue_notify(vbq->vq); } static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx, const struct blk_mq_queue_data *bd) { struct virtio_blk *vblk = hctx->queue->queuedata; + struct virtio_blk_vq *vbq = &vblk->vqs[hctx->queue_num]; struct request *req = bd->rq; struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); unsigned long flags; unsigned int num; - int qid = hctx->queue_num; int err; bool notify = false; bool unmap = false; @@ -274,16 +274,16 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx, vbr->out_hdr.type |= cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_IN); } - spin_lock_irqsave(&vblk->vqs[qid].lock, flags); - err = virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num); + spin_lock_irqsave(&vbq->lock, flags); + err = virtblk_add_req(vbq->vq, vbr, vbr->sg, num); if (err) { - virtqueue_kick(vblk->vqs[qid].vq); + virtqueue_kick(vbq->vq); /* Don't stop the queue if -ENOMEM: we may have failed to * bounce the buffer due to global resource outage. */ if (err == -ENOSPC) blk_mq_stop_hw_queue(hctx); - spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); + spin_unlock_irqrestore(&vbq->lock, flags); switch (err) { case -ENOSPC: return BLK_STS_DEV_RESOURCE; @@ -294,12 +294,12 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx, } } - if (bd->last && virtqueue_kick_prepare(vblk->vqs[qid].vq)) + if (bd->last && virtqueue_kick_prepare(vbq->vq)) notify = true; - spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); + spin_unlock_irqrestore(&vbq->lock, flags); if (notify) - virtqueue_notify(vblk->vqs[qid].vq); + virtqueue_notify(vbq->vq); return BLK_STS_OK; }
struct virtio_blk_vq is accessed in many places. Introduce "vbq" local variables to avoid repeating vblk->vqs[qid] throughout the code. The patches that follow will add more accesses, making the payoff even greater. virtio_commit_rqs() calls the local variable "vq", which is easily confused with struct virtqueue. Rename to "vbq" for clarity. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> --- drivers/block/virtio_blk.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-)