On 18/06/2012 16:09, Sasha Levin wrote:
Currently if VIRTIO_RING_F_INDIRECT_DESC is enabled we will use indirect descriptors and allocate them using a simple kmalloc(). This patch adds a cache which will allow indirect buffers under a configurable size to be allocated from that cache instead. Signed-off-by: Sasha Levin<levinsasha928@xxxxxxxxx> --- drivers/block/virtio_blk.c | 4 ++++ drivers/char/hw_random/virtio-rng.c | 4 ++++ drivers/char/virtio_console.c | 4 ++++ drivers/net/virtio_net.c | 4 ++++ drivers/virtio/virtio_balloon.c | 4 ++++ drivers/virtio/virtio_ring.c | 28 ++++++++++++++++++++++++---- include/linux/virtio.h | 1 + net/9p/trans_virtio.c | 5 +++++ 8 files changed, 50 insertions(+), 4 deletions(-) diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index a2c8d97..3c6d1bd 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -22,6 +22,9 @@ struct workqueue_struct *virtblk_wq; static unsigned int indirect_thresh = 0; module_param(indirect_thresh, uint, S_IRUGO); +static unsigned int indirect_alloc_thresh = 0; +module_param(indirect_alloc_thresh, uint, S_IRUGO); + struct virtio_blk { spinlock_t lock; @@ -442,6 +445,7 @@ static int __devinit virtblk_probe(struct virtio_device *vdev) INIT_WORK(&vblk->config_work, virtblk_config_changed_work); vblk->config_enable = true; vdev->indirect_thresh = indirect_thresh; + vdev->indirect_alloc_thresh = indirect_alloc_thresh; err = init_vq(vblk); if (err) diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c index bcaddb9..6a32f76 100644 --- a/drivers/char/hw_random/virtio-rng.c +++ b/drivers/char/hw_random/virtio-rng.c @@ -28,6 +28,9 @@ static unsigned int indirect_thresh = 0; module_param(indirect_thresh, uint, S_IRUGO); +static unsigned int indirect_alloc_thresh = 0; +module_param(indirect_alloc_thresh, uint, S_IRUGO); + static struct virtqueue *vq; static unsigned int data_avail; static DECLARE_COMPLETION(have_data); @@ -94,6 +97,7 @@ static int virtrng_probe(struct virtio_device *vdev) /* We expect a single virtqueue. */ vdev->indirect_thresh = indirect_thresh; + vdev->indirect_alloc_thresh = indirect_alloc_thresh; vq = virtio_find_single_vq(vdev, random_recv_done, "input"); if (IS_ERR(vq)) return PTR_ERR(vq); diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 60397a4..7c33714 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -40,6 +40,9 @@ static unsigned int indirect_thresh = 0; module_param(indirect_thresh, uint, S_IRUGO); +static unsigned int indirect_alloc_thresh = 0; +module_param(indirect_alloc_thresh, uint, S_IRUGO); + /* * This is a global struct for storing common data for all the devices * this driver handles. @@ -1733,6 +1736,7 @@ static int __devinit virtcons_probe(struct virtio_device *vdev) &portdev->config.max_nr_ports) == 0) multiport = true; vdev->indirect_thresh = indirect_thresh; + vdev->indirect_alloc_thresh = indirect_alloc_thresh; err = init_vqs(portdev); if (err< 0) { diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 5c1be92..441bd2f 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -37,6 +37,9 @@ module_param(gso, bool, 0444); static unsigned int indirect_thresh = 0; module_param(indirect_thresh, uint, S_IRUGO); +static unsigned int indirect_alloc_thresh = 0; +module_param(indirect_alloc_thresh, uint, S_IRUGO); + /* FIXME: MTU in config. */ #define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN) #define GOOD_COPY_LEN 128 @@ -1132,6 +1135,7 @@ static int virtnet_probe(struct virtio_device *vdev) if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) vi->mergeable_rx_bufs = true; vdev->indirect_thresh = indirect_thresh; + vdev->indirect_alloc_thresh = indirect_alloc_thresh; err = init_vqs(vi); if (err) diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 4fc11ba..6e6313b 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -38,6 +38,9 @@ static unsigned int indirect_thresh = 0; module_param(indirect_thresh, uint, S_IRUGO); +static unsigned int indirect_alloc_thresh = 0; +module_param(indirect_alloc_thresh, uint, S_IRUGO); + struct virtio_balloon { struct virtio_device *vdev; @@ -364,6 +367,7 @@ static int virtballoon_probe(struct virtio_device *vdev) vb->vdev = vdev; vb->need_stats_update = 0; vdev->indirect_thresh = indirect_thresh; + vdev->indirect_alloc_thresh = indirect_alloc_thresh; err = init_vqs(vb); if (err) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 99a64a7..f0b0ce3 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -93,6 +93,10 @@ struct vring_virtqueue */ unsigned int indirect_thresh; + /* Buffers below this size will be allocated from cache */ + unsigned int indirect_alloc_thresh; + struct kmem_cache *indirect_cache; + /* Host publishes avail event idx */ bool event; @@ -135,7 +139,10 @@ static int vring_add_indirect(struct vring_virtqueue *vq, unsigned head; int i; - desc = kmalloc((out + in) * sizeof(struct vring_desc), gfp); + if ((out + in)<= vq->indirect_alloc_thresh) + desc = kmem_cache_alloc(vq->indirect_cache, gfp); + else + desc = kmalloc((out + in) * sizeof(struct vring_desc), gfp); if (!desc) return -ENOMEM; @@ -384,8 +391,13 @@ static void detach_buf(struct vring_virtqueue *vq, unsigned int head) i = head; /* Free the indirect table */ - if (vq->vring.desc[i].flags& VRING_DESC_F_INDIRECT) - kfree(phys_to_virt(vq->vring.desc[i].addr)); + if (vq->vring.desc[i].flags& VRING_DESC_F_INDIRECT) { + if (vq->vring.desc[i].len< vq->indirect_alloc_thresh)
This should be > instead of <, no?
+ kfree(phys_to_virt(vq->vring.desc[i].addr)); + else + kmem_cache_free(vq->indirect_cache, + phys_to_virt(vq->vring.desc[i].addr)); + }
while (vq->vring.desc[i].flags& VRING_DESC_F_NEXT) { i = vq->vring.desc[i].next; @@ -654,14 +666,20 @@ struct virtqueue *vring_new_virtqueue(unsigned int num, vq->last_used_idx = 0; vq->num_added = 0; vq->indirect_thresh = 0; + vq->indirect_alloc_thresh = 0; + vq->indirect_cache = NULL; list_add_tail(&vq->vq.list,&vdev->vqs); #ifdef DEBUG vq->in_use = false; vq->last_add_time_valid = false; #endif - if (virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC)) + if (virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC)) { vq->indirect_thresh = vdev->indirect_thresh; + vq->indirect_alloc_thresh = vdev->indirect_alloc_thresh; + if (vq->indirect_alloc_thresh) + vq->indirect_cache = KMEM_CACHE(vring_desc[vq->indirect_alloc_thresh], 0); + } vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); @@ -685,6 +703,8 @@ EXPORT_SYMBOL_GPL(vring_new_virtqueue); void vring_del_virtqueue(struct virtqueue *vq) { list_del(&vq->list); + if (to_vvq(vq)->indirect_cache) + kmem_cache_destroy(to_vvq(vq)->indirect_cache); kfree(to_vvq(vq)); } EXPORT_SYMBOL_GPL(vring_del_virtqueue); diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 36019ec..f3f0d3f 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -70,6 +70,7 @@ struct virtio_device { unsigned long features[1]; void *priv; unsigned int indirect_thresh; + unsigned int indirect_alloc_thresh; }; #define dev_to_virtio(dev) container_of(dev, struct virtio_device, dev) diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c index 357bfba..8424b36 100644 --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -55,6 +55,9 @@ static unsigned int indirect_thresh = 0; module_param(indirect_thresh, uint, S_IRUGO); +static unsigned int indirect_alloc_thresh = 0; +module_param(indirect_alloc_thresh, uint, S_IRUGO); + /* a single mutex to manage channel initialization and attachment */ static DEFINE_MUTEX(virtio_9p_lock); static DECLARE_WAIT_QUEUE_HEAD(vp_wq); @@ -505,6 +508,8 @@ static int p9_virtio_probe(struct virtio_device *vdev) /* We expect one virtqueue, for requests. */ vdev->indirect_thresh = indirect_thresh; + vdev->indirect_alloc_thresh = indirect_alloc_thresh; + chan->vq = virtio_find_single_vq(vdev, req_done, "requests"); if (IS_ERR(chan->vq)) { err = PTR_ERR(chan->vq);
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