search for: pg_reserved

Dropping the reference count of PageOffline() pages allows offlining code to skip them. However, we also have to convert PG_reserved to another flag - let's use PG_dirty - so has_unmovable_pages() will properly handle them. PG_reserved pages get detected as unmovable right away. We need the flag to see if we are onlining pages the first time, or if we allocated them via alloc_contig_range(). Properly take care of offlining...

...ARRAY_SIZE(frame_list); + + spin_lock_irqsave(&balloon_lock, flags); + + if (!is_memory_resource_reserved()) { + + /* + * Look for first unused memory region starting at page + * boundary. Skip last memory section created at boot time + * becuase it may contains unused memory pages with PG_reserved + * bit not set (online_pages require PG_reserved bit set). + */ + + r = kzalloc(sizeof(struct resource), GFP_KERNEL); + + if (!r) { + rc = -ENOMEM; + goto out; + } + + r->name = "System RAM"; + r->flags = IORESOURCE_MEM | IORESOURCE_BUSY; + r_min = PFN_PHYS(section_nr...

Currently, virtio-mem does not really support ZONE_MOVABLE. While it allows to online fully plugged memory blocks to ZONE_MOVABLE, it does not allow to online partially-plugged memory blocks to ZONE_MOVABLE and will never consider such memory blocks when unplugging memory. This might be surprising for users (especially, if onlining suddenly fails). Let's support partially plugged memory

Currently, virtio-mem does not really support ZONE_MOVABLE. While it allows to online fully plugged memory blocks to ZONE_MOVABLE, it does not allow to online partially-plugged memory blocks to ZONE_MOVABLE and will never consider such memory blocks when unplugging memory. This might be surprising for users (especially, if onlining suddenly fails). Let's support partially plugged memory

@Andrew, @Mst, I suggest the whole series (including the virtio-mem change) goes via the -mm tree. Currently, virtio-mem does not really support ZONE_MOVABLE. While it allows to online fully plugged memory blocks to ZONE_MOVABLE, it does not allow to online partially-plugged memory blocks to ZONE_MOVABLE and will never consider such memory blocks when unplugging memory. This might be surprising

On Tue 22-10-19 16:02:09, David Hildenbrand wrote: [...] > >>> MEM_CANCEL_OFFLINE could gain the reference back to balance the > >>> MEM_GOING_OFFLINE step. > >> > >> The pages are already unisolated and could be used by the buddy. But again, > >> I think you have an idea that tries to avoid putting pages to the buddy. > > > > Yeah,

On Tue 22-10-19 16:02:09, David Hildenbrand wrote: [...] > >>> MEM_CANCEL_OFFLINE could gain the reference back to balance the > >>> MEM_GOING_OFFLINE step. > >> > >> The pages are already unisolated and could be used by the buddy. But again, > >> I think you have an idea that tries to avoid putting pages to the buddy. > > > > Yeah,

For 5.10. Patch #1-#4,#6 have RBs or ACKs, patch #5 is virtio-mem stuff maintained by me. This should go via the -mm tree. --- When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather unclear, which is why we special-cased ZONE_MOVABLE such that partially plugged blocks would never end up in ZONE_MOVABLE. Now that the semantics are much clearer (and are documented in patch #6),

For 5.10. Patch #1-#4,#6 have RBs or ACKs, patch #5 is virtio-mem stuff maintained by me. This should go via the -mm tree. --- When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather unclear, which is why we special-cased ZONE_MOVABLE such that partially plugged blocks would never end up in ZONE_MOVABLE. Now that the semantics are much clearer (and are documented in patch #6),

...gt;> I somewhat don't like forcing everybody that uses PageOffline() (especially >> all users of balloon compaction) to implement memory notifiers just to avoid >> that. Maybe, we even want to use PageOffline() in the future in the core >> (e.g., for memory holes instead of PG_reserved or similar). > > There is only a handful of those and we need to deal with them anyway. > If you do not want to enforce them to create their own notifiers then we > can accomodate the hotplug code. __test_page_isolated_in_pageblock resp. Yeah, I would prefer offlining code to be able...

...ntig_range) really need to mark >> @@ -8233,6 +8225,12 @@ struct page *has_unmovable_pages(struct zone *zone, struct page *page, >> >> page = pfn_to_page(pfn + iter); >> >> + /* >> + * Both, bootmem allocations and memory holes are marked >> + * PG_reserved and are unmovable. We can even have unmovable >> + * allocations inside ZONE_MOVABLE, for example when >> + * specifying "movable_core". > ~~~~ should be 'movablecore', we don't > have kernel parameter 'movable_core'...

...ogress). > > I somewhat don't like forcing everybody that uses PageOffline() (especially > all users of balloon compaction) to implement memory notifiers just to avoid > that. Maybe, we even want to use PageOffline() in the future in the core > (e.g., for memory holes instead of PG_reserved or similar). There is only a handful of those and we need to deal with them anyway. If you do not want to enforce them to create their own notifiers then we can accomodate the hotplug code. __test_page_isolated_in_pageblock resp. the call chain up can distinguish temporary and permanent failures (...

...ogress). > > I somewhat don't like forcing everybody that uses PageOffline() (especially > all users of balloon compaction) to implement memory notifiers just to avoid > that. Maybe, we even want to use PageOffline() in the future in the core > (e.g., for memory holes instead of PG_reserved or similar). There is only a handful of those and we need to deal with them anyway. If you do not want to enforce them to create their own notifiers then we can accomodate the hotplug code. __test_page_isolated_in_pageblock resp. the call chain up can distinguish temporary and permanent failures (...

@Andrew can we give this a churn and consider it for v5.9 in case there are no more comments? Patch #1-#4,#6 have RBss or ACKs, patch #5 is virtio-mem stuff maintained by me (and MST is aware). --- When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather unclear, which is why we special-cased ZONE_MOVABLE such that partially plugged blocks would never end up in ZONE_MOVABLE. Now

@Andrew can we give this a churn and consider it for v5.9 in case there are no more comments? Patch #1-#4,#6 have RBss or ACKs, patch #5 is virtio-mem stuff maintained by me (and MST is aware). --- When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather unclear, which is why we special-cased ZONE_MOVABLE such that partially plugged blocks would never end up in ZONE_MOVABLE. Now

...3,6 +8225,12 @@ struct page *has_unmovable_pages(struct zone *zone, struct page *page, >>>> >>>> page = pfn_to_page(pfn + iter); >>>> >>>> + /* >>>> + * Both, bootmem allocations and memory holes are marked >>>> + * PG_reserved and are unmovable. We can even have unmovable >>>> + * allocations inside ZONE_MOVABLE, for example when >>>> + * specifying "movable_core". >>> ~~~~ should be 'movablecore', we don't >>> have kernel...

@Andrew can we give this a churn and consider it for v5.9 in case there are no more comments? Patch #1-#4 have RB's, patch #5 is virtio-mem stuff maintained by me, patch #6 is just a doc update. --- Currently, virtio-mem does not really support ZONE_MOVABLE. While it allows to online fully plugged memory blocks to ZONE_MOVABLE, it does not allow to online partially-plugged memory blocks to

@Andrew can we give this a churn and consider it for v5.9 in case there are no more comments? Patch #1-#4 have RB's, patch #5 is virtio-mem stuff maintained by me, patch #6 is just a doc update. --- Currently, virtio-mem does not really support ZONE_MOVABLE. While it allows to online fully plugged memory blocks to ZONE_MOVABLE, it does not allow to online partially-plugged memory blocks to

...s); > > + > > + if (!is_memory_resource_reserved()) { > > + > > + /* > > + * Look for first unused memory region starting at page > > + * boundary. Skip last memory section created at boot time > > + * becuase it may contains unused memory pages with PG_reserved > > + * bit not set (online_pages require PG_reserved bit set). > > + */ > > + > > + r = kzalloc(sizeof(struct resource), GFP_KERNEL); > > You are holding a spinlock here. Kzalloc can sleep Thx. Fixed. On Fri, Aug 06, 2010 at 10:42:48AM -0700, Jeremy Fitzharding...

...there won't be progress). I somewhat don't like forcing everybody that uses PageOffline() (especially all users of balloon compaction) to implement memory notifiers just to avoid that. Maybe, we even want to use PageOffline() in the future in the core (e.g., for memory holes instead of PG_reserved or similar). Thanks! -- Thanks, David / dhildenb