search for: use_sg

...> + > > + return ret; > > +} > > + > > > > > @@ -172,11 +283,18 @@ static unsigned fill_balloon(struct virtio_balloon > *vb, size_t num) > > vb->num_pfns = 0; > > > > while ((page = balloon_page_pop(&pages))) { > > + if (use_sg) { > > + if (xb_set_page(vb, page, &pfn_min, &pfn_max) < 0) { > > + __free_page(page); > > + break; > > You cannot "break;" without consuming all pages in "pages". Right, I think it should be "continue" here. Thanks. >...

...fn(page); + + *pfn_min = min(pfn, *pfn_min); + *pfn_max = max(pfn, *pfn_max); + xb_set_bit(&vb->page_xb, pfn); +} + static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) { struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; unsigned num_allocated_pages; + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; /* We can only do one array worth at a time. */ - num = min(num, ARRAY_SIZE(vb->pfns)); + if (!use_sg) + num = min(num, ARRAY_SIZE(vb->pfns)); mutex_lock(&vb->balloon_lock...

...*pfn_max = max(pfn, *pfn_max); + xb_preload(GFP_KERNEL); + xb_set_bit(&vb->page_xb, pfn); + xb_preload_end(); +} + static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) { struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; unsigned num_allocated_pages; + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; /* We can only do one array worth at a time. */ - num = min(num, ARRAY_SIZE(vb->pfns)); + if (!use_sg) + num = min(num, ARRAY_SIZE(vb->pfns)); mutex_lock(&vb->balloon_lock...

...= xb_preload_and_set_bit(&vb->page_xb, pfn, GFP_KERNEL); + } while (unlikely(ret == -EAGAIN)); + + return ret; +} + static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) { unsigned num_allocated_pages; unsigned int num_pfns; struct page *page; LIST_HEAD(pages); + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; /* We can only do one array worth at a time. */ - num = min(num, ARRAY_SIZE(vb->pfns)); + if (!use_sg) + num = min(num, ARRAY_SIZE(vb->pfns)); for (num_pfns = 0; num_pfns < nu...

Wei Wang wrote: > @@ -164,6 +284,8 @@ static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > break; > } > > + if (use_sg && xb_set_page(vb, page, &pfn_min, &pfn_max) < 0) Isn't this leaking "page" ? > + break; > balloon_page_push(&pages, page); > } > > @@ -184,8 +307,12 @@ static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > >...

Wei Wang wrote: > @@ -164,6 +284,8 @@ static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > break; > } > > + if (use_sg && xb_set_page(vb, page, &pfn_min, &pfn_max) < 0) Isn't this leaking "page" ? > + break; > balloon_page_push(&pages, page); > } > > @@ -184,8 +307,12 @@ static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > >...

...it(&vb->page_xb, pfn, + GFP_NOWAIT | __GFP_NOWARN); + } while (unlikely(ret == -EAGAIN)); + + return ret; +} + static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) { unsigned num_allocated_pages; unsigned num_pfns; struct page *page; LIST_HEAD(pages); + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; /* We can only do one array worth at a time. */ - num = min(num, ARRAY_SIZE(vb->pfns)); + if (!use_sg) + num = min(num, ARRAY_SIZE(vb->pfns)); for (num_pfns = 0; num_pfns < nu...

...+ ret = xb_set_bit(&vb->page_xb, pfn); + xb_preload_end(); + } while (unlikely(ret == -EAGAIN)); + + return ret; +} + static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) { unsigned num_allocated_pages; unsigned num_pfns; struct page *page; LIST_HEAD(pages); + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; /* We can only do one array worth at a time. */ - num = min(num, ARRAY_SIZE(vb->pfns)); + if (!use_sg) + num = min(num, ARRAY_SIZE(vb->pfns)); for (num_pfns = 0; num_pfns < nu...

...+ ret = xb_set_bit(&vb->page_xb, pfn); + xb_preload_end(); + } while (unlikely(ret == -EAGAIN)); + + return ret; +} + static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) { unsigned num_allocated_pages; unsigned num_pfns; struct page *page; LIST_HEAD(pages); + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; /* We can only do one array worth at a time. */ - num = min(num, ARRAY_SIZE(vb->pfns)); + if (!use_sg) + num = min(num, ARRAY_SIZE(vb->pfns)); for (num_pfns = 0; num_pfns < nu...

...GFP_KERNEL); > + xb_set_bit(&vb->page_xb, pfn); > + xb_preload_end(); > +} > + > static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > { > struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; > unsigned num_allocated_pages; > + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); > + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; > > /* We can only do one array worth at a time. */ > - num = min(num, ARRAY_SIZE(vb->pfns)); > + if (!use_sg) > + num = min(num, ARRAY_SIZE(vb->pfns)); > &g...

...GFP_KERNEL); > + xb_set_bit(&vb->page_xb, pfn); > + xb_preload_end(); > +} > + > static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > { > struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; > unsigned num_allocated_pages; > + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); > + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; > > /* We can only do one array worth at a time. */ > - num = min(num, ARRAY_SIZE(vb->pfns)); > + if (!use_sg) > + num = min(num, ARRAY_SIZE(vb->pfns)); > &g...

...> + *pfn_max = max(pfn, *pfn_max); > + xb_set_bit(&vb->page_xb, pfn); > +} > + > static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > { > struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; > unsigned num_allocated_pages; > + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); > + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; > > /* We can only do one array worth at a time. */ > - num = min(num, ARRAY_SIZE(vb->pfns)); > + if (!use_sg) > + num = min(num, ARRAY_SIZE(vb->pfns)); > &g...

...> + *pfn_max = max(pfn, *pfn_max); > + xb_set_bit(&vb->page_xb, pfn); > +} > + > static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > { > struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; > unsigned num_allocated_pages; > + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); > + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; > > /* We can only do one array worth at a time. */ > - num = min(num, ARRAY_SIZE(vb->pfns)); > + if (!use_sg) > + num = min(num, ARRAY_SIZE(vb->pfns)); > &g...

..._max) +{ + unsigned long pfn = page_to_pfn(page); + + *pfn_min = min(pfn, *pfn_min); + *pfn_max = max(pfn, *pfn_max); +} + static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) { struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; unsigned num_allocated_pages; + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; /* We can only do one array worth at a time. */ - num = min(num, ARRAY_SIZE(vb->pfns)); + if (!use_sg) + num = min(num, ARRAY_SIZE(vb->pfns)); mutex_lock(&vb->balloon_lock...

...until there is some free memory? why GFP_NOWAIT? > + > + return ret; > +} > + > static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > { > unsigned num_allocated_pages; > unsigned num_pfns; > struct page *page; > LIST_HEAD(pages); > + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); > + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; > > /* We can only do one array worth at a time. */ > - num = min(num, ARRAY_SIZE(vb->pfns)); > + if (!use_sg) > + num = min(num, ARRAY_SIZE(vb->pfns)); > &g...

...until there is some free memory? why GFP_NOWAIT? > + > + return ret; > +} > + > static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > { > unsigned num_allocated_pages; > unsigned num_pfns; > struct page *page; > LIST_HEAD(pages); > + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); > + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; > > /* We can only do one array worth at a time. */ > - num = min(num, ARRAY_SIZE(vb->pfns)); > + if (!use_sg) > + num = min(num, ARRAY_SIZE(vb->pfns)); > &g...

This patch series enhances the existing virtio-balloon with the following new features: 1) fast ballooning: transfer ballooned pages between the guest and host in chunks using sgs, instead of one by one; and 2) free_page_vq: a new virtqueue to report guest free pages to the host. The second feature can be used to accelerate live migration of VMs. Here are some details: Live migration needs to

This patch series enhances the existing virtio-balloon with the following new features: 1) fast ballooning: transfer ballooned pages between the guest and host in chunks using sgs, instead of one by one; and 2) free_page_vq: a new virtqueue to report guest free pages to the host. The second feature can be used to accelerate live migration of VMs. Here are some details: Live migration needs to

...+ xb_preload_end(); > +} > + So, this will allocate memory ... > @@ -198,9 +327,12 @@ static unsigned leak_balloon(struct virtio_balloon *vb, size_t num) > struct page *page; > struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; > LIST_HEAD(pages); > + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); > + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; > > - /* We can only do one array worth at a time. */ > - num = min(num, ARRAY_SIZE(vb->pfns)); > + /* Traditionally, we can only do one array worth at a time. */ > + i...

...+ xb_preload_end(); > +} > + So, this will allocate memory ... > @@ -198,9 +327,12 @@ static unsigned leak_balloon(struct virtio_balloon *vb, size_t num) > struct page *page; > struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; > LIST_HEAD(pages); > + bool use_sg = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_SG); > + unsigned long pfn_max = 0, pfn_min = ULONG_MAX; > > - /* We can only do one array worth at a time. */ > - num = min(num, ARRAY_SIZE(vb->pfns)); > + /* Traditionally, we can only do one array worth at a time. */ > + i...