search for: virtio_balloon_page_bmap_size

...loon.c index ecb64e9..df16912 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -43,6 +43,20 @@ #define OOM_VBALLOON_DEFAULT_PAGES 256 #define VIRTBALLOON_OOM_NOTIFY_PRIORITY 80 +/* The size of one page_bmap used to record inflated/deflated pages. */ +#define VIRTIO_BALLOON_PAGE_BMAP_SIZE (8 * PAGE_SIZE) +/* + * Callulates how many pfns can a page_bmap record. A bit corresponds to a + * page of PAGE_SIZE. + */ +#define VIRTIO_BALLOON_PFNS_PER_PAGE_BMAP \ + (VIRTIO_BALLOON_PAGE_BMAP_SIZE * BITS_PER_BYTE) + +/* The number of page_bmap to allocate by default. */ +#define VIRTIO_BALLOON...

...; --- a/drivers/virtio/virtio_balloon.c > +++ b/drivers/virtio/virtio_balloon.c > @@ -43,6 +43,20 @@ > #define OOM_VBALLOON_DEFAULT_PAGES 256 > #define VIRTBALLOON_OOM_NOTIFY_PRIORITY 80 > > +/* The size of one page_bmap used to record inflated/deflated pages. */ > +#define VIRTIO_BALLOON_PAGE_BMAP_SIZE (8 * PAGE_SIZE) > +/* > + * Callulates how many pfns can a page_bmap record. A bit corresponds to a > + * page of PAGE_SIZE. > + */ > +#define VIRTIO_BALLOON_PFNS_PER_PAGE_BMAP \ > + (VIRTIO_BALLOON_PAGE_BMAP_SIZE * BITS_PER_BYTE) > + > +/* The number of page_bmap to allocat...

...; --- a/drivers/virtio/virtio_balloon.c > +++ b/drivers/virtio/virtio_balloon.c > @@ -43,6 +43,20 @@ > #define OOM_VBALLOON_DEFAULT_PAGES 256 > #define VIRTBALLOON_OOM_NOTIFY_PRIORITY 80 > > +/* The size of one page_bmap used to record inflated/deflated pages. */ > +#define VIRTIO_BALLOON_PAGE_BMAP_SIZE (8 * PAGE_SIZE) > +/* > + * Callulates how many pfns can a page_bmap record. A bit corresponds to a > + * page of PAGE_SIZE. > + */ > +#define VIRTIO_BALLOON_PFNS_PER_PAGE_BMAP \ > + (VIRTIO_BALLOON_PAGE_BMAP_SIZE * BITS_PER_BYTE) > + > +/* The number of page_bmap to allocat...

...945c 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -51,6 +51,36 @@ MODULE_PARM_DESC(oom_pages, "pages to free on OOM"); static struct vfsmount *balloon_mnt; #endif +/* The size of one page_bmap used to record inflated/deflated pages. */ +#define VIRTIO_BALLOON_PAGE_BMAP_SIZE (8 * PAGE_SIZE) +/* + * Callulates how many pfns can a page_bmap record. A bit corresponds to a + * page of PAGE_SIZE. + */ +#define VIRTIO_BALLOON_PFNS_PER_PAGE_BMAP \ + (VIRTIO_BALLOON_PAGE_BMAP_SIZE * BITS_PER_BYTE) + +/* The number of page_bmap to allocate by default. */ +#define VIRTIO_BALLOON...

...rtio_balloon.c > +++ b/drivers/virtio/virtio_balloon.c > @@ -51,6 +51,36 @@ MODULE_PARM_DESC(oom_pages, "pages to free on OOM"); > static struct vfsmount *balloon_mnt; > #endif > > +/* The size of one page_bmap used to record inflated/deflated pages. */ > +#define VIRTIO_BALLOON_PAGE_BMAP_SIZE (8 * PAGE_SIZE) At this size, you probably want alloc_pages to avoid kmalloc overhead. > +/* > + * Callulates how many pfns can a page_bmap record. A bit corresponds to a > + * page of PAGE_SIZE. > + */ > +#define VIRTIO_BALLOON_PFNS_PER_PAGE_BMAP \ > + (VIRTIO_BALLOON_PAGE_BMAP...

...rtio_balloon.c > +++ b/drivers/virtio/virtio_balloon.c > @@ -51,6 +51,36 @@ MODULE_PARM_DESC(oom_pages, "pages to free on OOM"); > static struct vfsmount *balloon_mnt; > #endif > > +/* The size of one page_bmap used to record inflated/deflated pages. */ > +#define VIRTIO_BALLOON_PAGE_BMAP_SIZE (8 * PAGE_SIZE) At this size, you probably want alloc_pages to avoid kmalloc overhead. > +/* > + * Callulates how many pfns can a page_bmap record. A bit corresponds to a > + * page of PAGE_SIZE. > + */ > +#define VIRTIO_BALLOON_PFNS_PER_PAGE_BMAP \ > + (VIRTIO_BALLOON_PAGE_BMAP...

This patch series implements the follow two things: 1) Optimization of balloon page transfer: instead of transferring balloon pages to host one by one, the new mechanism transfers them in chunks. 2) A mechanism to report info of guest unused pages: the pages have been unused at some time between when host sent command and when guest reported them. Host uses that by tracking memory changes and

This patch series implements the follow two things: 1) Optimization of balloon page transfer: instead of transferring balloon pages to host one by one, the new mechanism transfers them in chunks. 2) A mechanism to report info of guest unused pages: the pages have been unused at some time between when host sent command and when guest reported them. Host uses that by tracking memory changes and

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, instead of one by one; and 2) cmdq: a new virtqueue to send commands between the device and driver. Currently, it supports commands to report memory stats (replace the old statq mechanism) and report guest unused pages. Liang Li

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, instead of one by one; and 2) cmdq: a new virtqueue to send commands between the device and driver. Currently, it supports commands to report memory stats (replace the old statq mechanism) and report guest unused pages. Liang Li

On 06/13/2017 10:56 AM, Michael S. Tsirkin wrote: >> +/* The size of one page_bmap used to record inflated/deflated pages. */ >> +#define VIRTIO_BALLOON_PAGE_BMAP_SIZE (8 * PAGE_SIZE) > At this size, you probably want alloc_pages to avoid kmalloc > overhead. For slub, at least, kmalloc() just calls alloc_pages() basically directly. There's virtually no overhead.

...; static struct vfsmount *balloon_mnt; #endif +/* Types of pages to chunk */ +#define PAGE_CHUNK_TYPE_BALLOON 0 /* Chunk of inflate/deflate pages */ +#define PAGE_CHNUK_UNUSED_PAGE 1 /* Chunk of unused pages */ + /* The size of one page_bmap used to record inflated/deflated pages. */ #define VIRTIO_BALLOON_PAGE_BMAP_SIZE (8 * PAGE_SIZE) /* @@ -81,12 +85,25 @@ struct virtio_balloon_page_chunk { unsigned long *page_bmap[VIRTIO_BALLOON_PAGE_BMAP_MAX_NUM]; }; +struct virtio_balloon_cmdq_unused_page { + struct virtio_balloon_cmdq_hdr hdr; + struct vring_desc *desc_table; + /* Number of added descriptors */ + unsig...

...ng_desc) to describe a chunk. This avoids the overhead of kmalloc() the indirect table. >> +/* >> + * Callulates how many pfns can a page_bmap record. A bit corresponds to a >> + * page of PAGE_SIZE. >> + */ >> +#define VIRTIO_BALLOON_PFNS_PER_PAGE_BMAP \ >> + (VIRTIO_BALLOON_PAGE_BMAP_SIZE * BITS_PER_BYTE) >> + >> +/* The number of page_bmap to allocate by default. */ >> +#define VIRTIO_BALLOON_PAGE_BMAP_DEFAULT_NUM 1 > It's not by default, it's at probe time, right? It is the number of page bitmap being kept throughout the whole lifecycle of the driver....