search for: arch_free_pages

...lve that problem. It is not migration specific. > > If we are looking for an alternative to "problem solves itself", > something like "if virtio-balloon comes up, it will report all free > pages step by step using free page hinting, just like we would have from > "arch_free_pages()"". This would be the same interface we are using for > free page hinting - and it could even be made configurable in the guest. > > The current approach we are discussing internally for details about > Nitesh's work ("how the magic inside arch_fee_pages() will work...

...lve that problem. It is not migration specific. > > If we are looking for an alternative to "problem solves itself", > something like "if virtio-balloon comes up, it will report all free > pages step by step using free page hinting, just like we would have from > "arch_free_pages()"". This would be the same interface we are using for > free page hinting - and it could even be made configurable in the guest. > > The current approach we are discussing internally for details about > Nitesh's work ("how the magic inside arch_fee_pages() will work...

On 06/27/2018 07:06 PM, David Hildenbrand wrote: > On 25.06.2018 14:05, Wei Wang wrote: >> This patch series is separated from the previous "Virtio-balloon >> Enhancement" series. The new feature, VIRTIO_BALLOON_F_FREE_PAGE_HINT, >> implemented by this series enables the virtio-balloon driver to report >> hints of guest free pages to the host. It can be used to

On 06/27/2018 07:06 PM, David Hildenbrand wrote: > On 25.06.2018 14:05, Wei Wang wrote: >> This patch series is separated from the previous "Virtio-balloon >> Enhancement" series. The new feature, VIRTIO_BALLOON_F_FREE_PAGE_HINT, >> implemented by this series enables the virtio-balloon driver to report >> hints of guest free pages to the host. It can be used to

...is not migration specific. >> >> If we are looking for an alternative to "problem solves itself", >> something like "if virtio-balloon comes up, it will report all free >> pages step by step using free page hinting, just like we would have from >> "arch_free_pages()"". This would be the same interface we are using for >> free page hinting - and it could even be made configurable in the guest. >> >> The current approach we are discussing internally for details about >> Nitesh's work ("how the magic inside arch_fee_pa...

On 20.06.2017 18:44, Rik van Riel wrote: > On Mon, 2017-06-12 at 07:10 -0700, Dave Hansen wrote: > >> The hypervisor is going to throw away the contents of these pages, >> right? As soon as the spinlock is released, someone can allocate a >> page, and put good data in it. What keeps the hypervisor from >> throwing >> away good data? > > That looks like

On 20.06.2017 18:44, Rik van Riel wrote: > On Mon, 2017-06-12 at 07:10 -0700, Dave Hansen wrote: > >> The hypervisor is going to throw away the contents of these pages, >> right? As soon as the spinlock is released, someone can allocate a >> page, and put good data in it. What keeps the hypervisor from >> throwing >> away good data? > > That looks like

...c. > >> > >> If we are looking for an alternative to "problem solves itself", > >> something like "if virtio-balloon comes up, it will report all free > >> pages step by step using free page hinting, just like we would have > >> from "arch_free_pages()"". This would be the same interface we are > >> using for free page hinting - and it could even be made configurable in the > guest. > >> > >> The current approach we are discussing internally for details about > >> Nitesh's work ("how the...

..., so we should rather solve that problem. It is not migration specific. If we are looking for an alternative to "problem solves itself", something like "if virtio-balloon comes up, it will report all free pages step by step using free page hinting, just like we would have from "arch_free_pages()"". This would be the same interface we are using for free page hinting - and it could even be made configurable in the guest. The current approach we are discussing internally for details about Nitesh's work ("how the magic inside arch_fee_pages() will work efficiently) would...

...ce and even turn > > virtio-balloon in some sense useless. > > I agree with that. Let me go into some more detail of > what Nitesh is implementing: > > 1) In arch_free_page, the being-freed page is added > to a per-cpu set of freed pages. > 2) Once that set is full, arch_free_pages goes into a > slow path, which: > 2a) Iterates over the set of freed pages, and > 2b) Checks whether they are still free, and > 2c) Adds the still free pages to a list that is > to be passed to the hypervisor, to be MADV_FREEd. > 2d) Makes that hypercall. &gt...

...ce and even turn > > virtio-balloon in some sense useless. > > I agree with that. Let me go into some more detail of > what Nitesh is implementing: > > 1) In arch_free_page, the being-freed page is added > to a per-cpu set of freed pages. > 2) Once that set is full, arch_free_pages goes into a > slow path, which: > 2a) Iterates over the set of freed pages, and > 2b) Checks whether they are still free, and > 2c) Adds the still free pages to a list that is > to be passed to the hypervisor, to be MADV_FREEd. > 2d) Makes that hypercall. &gt...

From: Martin Schwidefsky <schwidefsky@de.ibm.com> From: Hubertus Franke <frankeh@watson.ibm.com> From: Himanshu Raj <rhim@cc.gatech.edu> [patch 1/9] Guest page hinting: unused / free pages. A very simple but already quite effective improvement in the handling of guest memory vs. host memory is to tell the host when pages are free. That allows the host to avoid the paging of

From: Martin Schwidefsky <schwidefsky@de.ibm.com> From: Hubertus Franke <frankeh@watson.ibm.com> From: Himanshu Raj <rhim@cc.gatech.edu> [patch 1/9] Guest page hinting: unused / free pages. A very simple but already quite effective improvement in the handling of guest memory vs. host memory is to tell the host when pages are free. That allows the host to avoid the paging of

...ight. This would avoid the batch interface and even turn > virtio-balloon in some sense useless. I agree with that. Let me go into some more detail of what Nitesh is implementing: 1) In arch_free_page, the being-freed page is added to a per-cpu set of freed pages. 2) Once that set is full, arch_free_pages goes into a slow path, which: 2a) Iterates over the set of freed pages, and 2b) Checks whether they are still free, and 2c) Adds the still free pages to a list that is to be passed to the hypervisor, to be MADV_FREEd. 2d) Makes that hypercall. Meanwhile all arch_alloc_pages h...

On Wed, Jun 27, 2018 at 01:06:32PM +0200, David Hildenbrand wrote: > On 25.06.2018 14:05, Wei Wang wrote: > > This patch series is separated from the previous "Virtio-balloon > > Enhancement" series. The new feature, VIRTIO_BALLOON_F_FREE_PAGE_HINT, > > implemented by this series enables the virtio-balloon driver to report > > hints of guest free pages to the

On Wed, Jun 27, 2018 at 01:06:32PM +0200, David Hildenbrand wrote: > On 25.06.2018 14:05, Wei Wang wrote: > > This patch series is separated from the previous "Virtio-balloon > > Enhancement" series. The new feature, VIRTIO_BALLOON_F_FREE_PAGE_HINT, > > implemented by this series enables the virtio-balloon driver to report > > hints of guest free pages to the

On 20.06.2017 20:17, Michael S. Tsirkin wrote: > On Tue, Jun 20, 2017 at 06:49:33PM +0200, David Hildenbrand wrote: >> On 20.06.2017 18:44, Rik van Riel wrote: >>> On Mon, 2017-06-12 at 07:10 -0700, Dave Hansen wrote: >>> >>>> The hypervisor is going to throw away the contents of these pages, >>>> right? As soon as the spinlock is released,

On 20.06.2017 20:17, Michael S. Tsirkin wrote: > On Tue, Jun 20, 2017 at 06:49:33PM +0200, David Hildenbrand wrote: >> On 20.06.2017 18:44, Rik van Riel wrote: >>> On Mon, 2017-06-12 at 07:10 -0700, Dave Hansen wrote: >>> >>>> The hypervisor is going to throw away the contents of these pages, >>>> right? As soon as the spinlock is released,

Please stop cc'ing me on things also sent to closed mailing lists (virtio-dev at lists.oasis-open.org). I'm happy to review things on open lists, but I'm not fond of the closed lists bouncing things at me. On 06/09/2017 03:41 AM, Wei Wang wrote: > Add a function to find a page block on the free list specified by the > caller. Pages from the page block may be used immediately

Please stop cc'ing me on things also sent to closed mailing lists (virtio-dev at lists.oasis-open.org). I'm happy to review things on open lists, but I'm not fond of the closed lists bouncing things at me. On 06/09/2017 03:41 AM, Wei Wang wrote: > Add a function to find a page block on the free list specified by the > caller. Pages from the page block may be used immediately