hw/virtio/virtio-balloon.c | 176 ++++++++++++++++++----- include/hw/virtio/virtio-balloon.h | 23 ++- include/standard-headers/linux/virtio_balloon.h | 12 +- 3 files changed, 159 insertions(+), 52 deletions(-)
This series provides an asynchronous means of reporting free guest pages
to QEMU through virtio-balloon so that the memory associated with those
pages can be dropped and reused by other processes and/or guests on the
host. Using this it is possible to avoid unnecessary I/O to disk and
greatly improve performance in the case of memory overcommit on the host.
I originally submitted this patch series back on February 11th 2020[1],
but at that time I was focused primarily on the kernel portion of this
patch set. However as of April 7th those patches are now included in
Linus's kernel tree[2] and so I am submitting the QEMU pieces for
inclusion.
[1]: https://lore.kernel.org/lkml/20200211224416.29318.44077.stgit@localhost.localdomain/
[2]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b0c504f154718904ae49349147e3b7e6ae91ffdc
Changes from v17:
Fixed typo in patch 1 title
Addressed white-space issues reported via checkpatch
Added braces {} for two if statements to match expected coding style
Changes from v18:
Updated patches 2 and 3 based on input from dhildenb
Added comment to patch 2 describing what keeps us from reporting a bad page
Added patch to address issue with ROM devices being directly writable
Changes from v19:
Added std-headers change to match changes pushed for linux kernel headers
Added patch to remove "report" from page hinting code paths
Updated comment to better explain why we disable hints w/ page poisoning
Removed code that was modifying config size for poison vs hinting
Dropped x-page-poison property
Added code to bounds check the reported region vs the RAM block
Dropped patch for ROM devices as that was already pulled in by Paolo
Changes from v20:
Rearranged patches to push Linux header sync patches to front
Removed association between free page hinting and VIRTIO_BALLOON_F_PAGE_POISON
Added code to enable VIRTIO_BALLOON_F_PAGE_POISON if page reporting is enabled
Fixed possible resource leak if poison or qemu_balloon_is_inhibited return true
Changes from v21:
Added ack for patch 3
Rewrote patch description for page poison reporting feature
Made page-poison independent property and set to enabled by default
Added logic to migrate poison_val
Added several comments in code to better explain features
Switched free-page-reporting property to disabled by default
Changes from v22:
Added ack for patches 4 & 5
Added additional comment fixes in patch 3 to remove "reporting" reference
Renamed rvq in patch 5 to reporting_vq to improve readability
Moved call adding reporting_vq to after free_page_vq to fix VQ ordering
---
Alexander Duyck (5):
linux-headers: Update to allow renaming of free_page_report_cmd_id
linux-headers: update to contain virito-balloon free page reporting
virtio-balloon: Replace free page hinting references to 'report' with 'hint'
virtio-balloon: Implement support for page poison reporting feature
virtio-balloon: Provide an interface for free page reporting
hw/virtio/virtio-balloon.c | 176 ++++++++++++++++++-----
include/hw/virtio/virtio-balloon.h | 23 ++-
include/standard-headers/linux/virtio_balloon.h | 12 +-
3 files changed, 159 insertions(+), 52 deletions(-)
--
I just wanted to follow up since it has been a little over a week
since I submitted this and I haven't heard anything back. It looks
like the linux-headers patches can be dropped since the headers appear
to have been synced. I was wondering if I should resubmit with just
the 3 patches that are adding the functionality, or if this patch-set
is good as-is?
Thanks.
- Alex
On Mon, Apr 27, 2020 at 5:53 PM Alexander Duyck
<alexander.duyck@gmail.com> wrote:
>
> This series provides an asynchronous means of reporting free guest pages
> to QEMU through virtio-balloon so that the memory associated with those
> pages can be dropped and reused by other processes and/or guests on the
> host. Using this it is possible to avoid unnecessary I/O to disk and
> greatly improve performance in the case of memory overcommit on the host.
>
> I originally submitted this patch series back on February 11th 2020[1],
> but at that time I was focused primarily on the kernel portion of this
> patch set. However as of April 7th those patches are now included in
> Linus's kernel tree[2] and so I am submitting the QEMU pieces for
> inclusion.
>
> [1]: https://lore.kernel.org/lkml/20200211224416.29318.44077.stgit@localhost.localdomain/
> [2]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b0c504f154718904ae49349147e3b7e6ae91ffdc
>
> Changes from v17:
> Fixed typo in patch 1 title
> Addressed white-space issues reported via checkpatch
> Added braces {} for two if statements to match expected coding style
>
> Changes from v18:
> Updated patches 2 and 3 based on input from dhildenb
> Added comment to patch 2 describing what keeps us from reporting a bad page
> Added patch to address issue with ROM devices being directly writable
>
> Changes from v19:
> Added std-headers change to match changes pushed for linux kernel headers
> Added patch to remove "report" from page hinting code paths
> Updated comment to better explain why we disable hints w/ page poisoning
> Removed code that was modifying config size for poison vs hinting
> Dropped x-page-poison property
> Added code to bounds check the reported region vs the RAM block
> Dropped patch for ROM devices as that was already pulled in by Paolo
>
> Changes from v20:
> Rearranged patches to push Linux header sync patches to front
> Removed association between free page hinting and VIRTIO_BALLOON_F_PAGE_POISON
> Added code to enable VIRTIO_BALLOON_F_PAGE_POISON if page reporting is enabled
> Fixed possible resource leak if poison or qemu_balloon_is_inhibited return true
>
> Changes from v21:
> Added ack for patch 3
> Rewrote patch description for page poison reporting feature
> Made page-poison independent property and set to enabled by default
> Added logic to migrate poison_val
> Added several comments in code to better explain features
> Switched free-page-reporting property to disabled by default
>
> Changes from v22:
> Added ack for patches 4 & 5
> Added additional comment fixes in patch 3 to remove "reporting" reference
> Renamed rvq in patch 5 to reporting_vq to improve readability
> Moved call adding reporting_vq to after free_page_vq to fix VQ ordering
>
> ---
>
> Alexander Duyck (5):
> linux-headers: Update to allow renaming of free_page_report_cmd_id
> linux-headers: update to contain virito-balloon free page reporting
> virtio-balloon: Replace free page hinting references to 'report' with 'hint'
> virtio-balloon: Implement support for page poison reporting feature
> virtio-balloon: Provide an interface for free page reporting
>
>
> hw/virtio/virtio-balloon.c | 176 ++++++++++++++++++-----
> include/hw/virtio/virtio-balloon.h | 23 ++-
> include/standard-headers/linux/virtio_balloon.h | 12 +-
> 3 files changed, 159 insertions(+), 52 deletions(-)
>
> --
> Am 08.05.2020 um 19:31 schrieb Alexander Duyck <alexander.duyck@gmail.com>:
>
> I just wanted to follow up since it has been a little over a week
> since I submitted this and I haven't heard anything back. It looks
> like the linux-headers patches can be dropped since the headers appear
> to have been synced. I was wondering if I should resubmit with just
> the 3 patches that are adding the functionality, or if this patch-set
> is good as-is?
Should be good as-is. However, if the new compat machines are already upstream, you might want to tackle that right away.
Cheers and have a nice weekend!
>
> Thanks.
>
> - Alex
>
>> On Mon, Apr 27, 2020 at 5:53 PM Alexander Duyck
>> <alexander.duyck@gmail.com> wrote:
>>
>> This series provides an asynchronous means of reporting free guest pages
>> to QEMU through virtio-balloon so that the memory associated with those
>> pages can be dropped and reused by other processes and/or guests on the
>> host. Using this it is possible to avoid unnecessary I/O to disk and
>> greatly improve performance in the case of memory overcommit on the host.
>>
>> I originally submitted this patch series back on February 11th 2020[1],
>> but at that time I was focused primarily on the kernel portion of this
>> patch set. However as of April 7th those patches are now included in
>> Linus's kernel tree[2] and so I am submitting the QEMU pieces for
>> inclusion.
>>
>> [1]: https://lore.kernel.org/lkml/20200211224416.29318.44077.stgit@localhost.localdomain/
>> [2]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b0c504f154718904ae49349147e3b7e6ae91ffdc
>>
>> Changes from v17:
>> Fixed typo in patch 1 title
>> Addressed white-space issues reported via checkpatch
>> Added braces {} for two if statements to match expected coding style
>>
>> Changes from v18:
>> Updated patches 2 and 3 based on input from dhildenb
>> Added comment to patch 2 describing what keeps us from reporting a bad page
>> Added patch to address issue with ROM devices being directly writable
>>
>> Changes from v19:
>> Added std-headers change to match changes pushed for linux kernel headers
>> Added patch to remove "report" from page hinting code paths
>> Updated comment to better explain why we disable hints w/ page poisoning
>> Removed code that was modifying config size for poison vs hinting
>> Dropped x-page-poison property
>> Added code to bounds check the reported region vs the RAM block
>> Dropped patch for ROM devices as that was already pulled in by Paolo
>>
>> Changes from v20:
>> Rearranged patches to push Linux header sync patches to front
>> Removed association between free page hinting and VIRTIO_BALLOON_F_PAGE_POISON
>> Added code to enable VIRTIO_BALLOON_F_PAGE_POISON if page reporting is enabled
>> Fixed possible resource leak if poison or qemu_balloon_is_inhibited return true
>>
>> Changes from v21:
>> Added ack for patch 3
>> Rewrote patch description for page poison reporting feature
>> Made page-poison independent property and set to enabled by default
>> Added logic to migrate poison_val
>> Added several comments in code to better explain features
>> Switched free-page-reporting property to disabled by default
>>
>> Changes from v22:
>> Added ack for patches 4 & 5
>> Added additional comment fixes in patch 3 to remove "reporting" reference
>> Renamed rvq in patch 5 to reporting_vq to improve readability
>> Moved call adding reporting_vq to after free_page_vq to fix VQ ordering
>>
>> ---
>>
>> Alexander Duyck (5):
>> linux-headers: Update to allow renaming of free_page_report_cmd_id
>> linux-headers: update to contain virito-balloon free page reporting
>> virtio-balloon: Replace free page hinting references to 'report' with 'hint'
>> virtio-balloon: Implement support for page poison reporting feature
>> virtio-balloon: Provide an interface for free page reporting
>>
>>
>> hw/virtio/virtio-balloon.c | 176 ++++++++++++++++++-----
>> include/hw/virtio/virtio-balloon.h | 23 ++-
>> include/standard-headers/linux/virtio_balloon.h | 12 +-
>> 3 files changed, 159 insertions(+), 52 deletions(-)
>>
>> --
>
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