similar to: [PATCH v20 0/7] Virtio-balloon Enhancement

On 12/19/2017 10:05 PM, Tetsuo Handa wrote: > Wei Wang wrote: >> ChangeLog: >> v19->v20: >> 1) patch 1: xbitmap >> - add __rcu to "void **slot"; >> - remove the exceptional path. >> 2) patch 3: xbitmap >> - DeveloperNotes: add an item to comment that the current bit range >> related APIs operating on extremely large ranges (e.g.

On 12/19/2017 10:05 PM, Tetsuo Handa wrote: > Wei Wang wrote: >> ChangeLog: >> v19->v20: >> 1) patch 1: xbitmap >> - add __rcu to "void **slot"; >> - remove the exceptional path. >> 2) patch 3: xbitmap >> - DeveloperNotes: add an item to comment that the current bit range >> related APIs operating on extremely large ranges (e.g.

This patch adds support to find next 1 or 0 bit in a xbmitmap range and clear a range of bits. More possible optimizations to add in the future: 1) xb_set_bit_range: set a range of bits. 2) when searching a bit, if the bit is not found in the slot, move on to the next slot directly. 3) add tags to help searching. Signed-off-by: Wei Wang <wei.w.wang at intel.com> Cc: Matthew Wilcox

OK, here's a rewrite of xbitmap. Compared to the version you sent: - xb_find_set() is the rewrite I sent out yesterday. - xb_find_clear() is a new implementation. I use the IDR_FREE tag to find clear bits. This led to me finding a bug in radix_tree_for_each_tagged(). - xb_zero() is also a new implementation (replacing xb_clear_bit_range). It should also be more efficient in deep

On Wed, Dec 20, 2017 at 04:13:16PM +0000, Wang, Wei W wrote: > On Wednesday, December 20, 2017 8:26 PM, Matthew Wilcox wrote: > > unsigned long bit; > > xb_preload(GFP_KERNEL); > > xb_set_bit(xb, 700); > > xb_preload_end(); > > bit = xb_find_set(xb, ULONG_MAX, 0); > > assert(bit == 700); > > This above test will result in "!node with bitmap

This patch adds support to find next 1 or 0 bit in a xbmitmap range and clear a range of bits. More possible optimizations to add in the future: 1) xb_set_bit_range: set a range of bits. 2) when searching a bit, if the bit is not found in the slot, move on to the next slot directly. 3) add tags to help searching. Signed-off-by: Wei Wang <wei.w.wang at intel.com> Cc: Matthew Wilcox

This patch adds support to find next 1 or 0 bit in a xbmitmap range and clear a range of bits. More possible optimizations to add in the future: 1) xb_set_bit_range: set a range of bits. 2) when searching a bit, if the bit is not found in the slot, move on to the next slot directly. 3) add tags to help searching. Signed-off-by: Wei Wang <wei.w.wang at intel.com> Cc: Matthew Wilcox

On 12/22/2017 05:03 AM, Matthew Wilcox wrote: > OK, here's a rewrite of xbitmap. > > Compared to the version you sent: > - xb_find_set() is the rewrite I sent out yesterday. > - xb_find_clear() is a new implementation. I use the IDR_FREE tag to find > clear bits. This led to me finding a bug in radix_tree_for_each_tagged(). > - xb_zero() is also a new

On 12/22/2017 05:03 AM, Matthew Wilcox wrote: > OK, here's a rewrite of xbitmap. > > Compared to the version you sent: > - xb_find_set() is the rewrite I sent out yesterday. > - xb_find_clear() is a new implementation. I use the IDR_FREE tag to find > clear bits. This led to me finding a bug in radix_tree_for_each_tagged(). > - xb_zero() is also a new

From: Matthew Wilcox <mawilcox at microsoft.com> Add the following tests for xbitmap: 1) single bit test: single bit set/clear/find; 2) bit range test: set/clear a range of bits and find a 0 or 1 bit in the range. Signed-off-by: Wei Wang <wei.w.wang at intel.com> Cc: Matthew Wilcox <mawilcox at microsoft.com> Cc: Andrew Morton <akpm at linux-foundation.org> Cc: Michael S.

From: Matthew Wilcox <mawilcox at microsoft.com> The eXtensible Bitmap is a sparse bitmap representation which is efficient for set bits which tend to cluster. It supports up to 'unsigned long' worth of bits, and this commit adds the bare bones -- xb_set_bit(), xb_clear_bit(), xb_clear_bit_range(), xb_test_bit(), xb_find_next_set_bit(), xb_find_next_zero_bit(). More possible

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 array each time; and 2) free page block reporting: 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

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 array each time; and 2) free page block reporting: 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

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 array each time; and 2) free page block reporting: 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

On 12/21/2017 10:37 PM, Tetsuo Handa wrote: > Matthew Wilcox wrote: >>> +/** >>> + * xb_find_set - find the next set bit in a range of bits >>> + * @xb: the xbitmap to search from >>> + * @offset: the offset in the range to start searching >>> + * @size: the size of the range >>> + * >>> + * Returns: the found bit or, @size if no

On Tue, Dec 19, 2017 at 11:05:11PM +0900, Tetsuo Handa wrote: > Removing exceptional path made this patch easier to read. > But what I meant is > > Can you eliminate exception path and fold all xbitmap patches into one, and > post only one xbitmap patch without virtio-balloon changes? > > . > > I still think we don't need xb_preload()/xb_preload_end(). > I

On Tue, Dec 19, 2017 at 11:05:11PM +0900, Tetsuo Handa wrote: > Removing exceptional path made this patch easier to read. > But what I meant is > > Can you eliminate exception path and fold all xbitmap patches into one, and > post only one xbitmap patch without virtio-balloon changes? > > . > > I still think we don't need xb_preload()/xb_preload_end(). > I

From: Matthew Wilcox <mawilcox at microsoft.com> The eXtensible Bitmap is a sparse bitmap representation which is efficient for set bits which tend to cluster. It supports up to 'unsigned long' worth of bits. Signed-off-by: Matthew Wilcox <mawilcox at microsoft.com> Signed-off-by: Wei Wang <wei.w.wang at intel.com> Cc: Andrew Morton <akpm at linux-foundation.org>

On 12/21/2017 01:10 AM, Matthew Wilcox wrote: > On Wed, Dec 20, 2017 at 04:13:16PM +0000, Wang, Wei W wrote: >> On Wednesday, December 20, 2017 8:26 PM, Matthew Wilcox wrote: >>> unsigned long bit; >>> xb_preload(GFP_KERNEL); >>> xb_set_bit(xb, 700); >>> xb_preload_end(); >>> bit = xb_find_set(xb, ULONG_MAX, 0); >>> assert(bit ==

Add a new feature, VIRTIO_BALLOON_F_SG, which enables the transfer of balloon (i.e. inflated/deflated) pages using scatter-gather lists to the host. The implementation of the previous virtio-balloon is not very efficient, because the balloon pages are transferred to the host by one array each time. Here is the breakdown of the time in percentage spent on each step of the balloon inflating process