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* migration: Remove masking for compressionJuan Quintela2022-01-281-2/+2
| | | | | | | | Remove the mask in the call to ram_release_pages(). Nothing else does it, and if the offset has that bits set, we have a lot of trouble. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: ram_release_pages() always receive 1 page as argumentJuan Quintela2022-01-281-4/+4
| | | | | | | | | | | | | Remove the pages argument. And s/pages/page/ Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> --- - Use 1LL instead of casts (philmd) - Change the whole 1ULL for TARGET_PAGE_SIZE
* migration: We only need last_stage in two placesJuan Quintela2022-01-281-23/+18
| | | | | | | | | | | | We only need last_stage in two places and we are passing it all around. Just add a field to RAMState that passes it. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> --- Repeat subject (philmd suggestion)
* migration: Remove is_zero_range()Juan Quintela2021-12-151-7/+2
| | | | | | | It just calls buffer_is_zero(). Just change the callers. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
* migration/ram.c: Remove the qemu_mutex_lock in colo_flush_ram_cache.Rao, Lei2021-12-151-2/+0
| | | | | | | | | | | | | | | The code to acquire bitmap_mutex is added in the commit of "63268c4970a5f126cc9af75f3ccb8057abef5ec0". There is no need to acquire bitmap_mutex in colo_flush_ram_cache(). This is because the colo_flush_ram_cache only be called on the COLO secondary VM, which is the destination side. On the COLO secondary VM, only the COLO thread will touch the bitmap of ram cache. Signed-off-by: Lei Rao <lei.rao@intel.com> Reviewed-by: Zhang Chen <chen.zhang@intel.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* Reset the auto-converge counter at every checkpoint.Rao, Lei2021-11-091-0/+9
| | | | | | | | | | | | | | if we don't reset the auto-converge counter, it will continue to run with COLO running, and eventually the system will hang due to the CPU throttle reaching DEFAULT_MIGRATE_MAX_CPU_THROTTLE. Signed-off-by: Lei Rao <lei.rao@intel.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Lukas Straub <lukasstraub2@web.de> Tested-by: Lukas Straub <lukasstraub2@web.de> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* Reduce the PVM stop time during CheckpointRao, Lei2021-11-091-3/+45
| | | | | | | | | | | | | When flushing memory from ram cache to ram during every checkpoint on secondary VM, we can copy continuous chunks of memory instead of 4096 bytes per time to reduce the time of VM stop during checkpoint. Signed-off-by: Lei Rao <lei.rao@intel.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Lukas Straub <lukasstraub2@web.de> Reviewed-by: Juan Quintela <quintela@redhat.com> Tested-by: Lukas Straub <lukasstraub2@web.de> Signed-off-by: Juan Quintela <quintela@redhat.com>
* colo: Don't dump colo cache if dump-guest-core=offLukas Straub2021-11-031-0/+6
| | | | | | | | | | One might set dump-guest-core=off to make coredumps smaller and still allow to debug many qemu bugs. Extend this option to the colo cache. Signed-off-by: Lukas Straub <lukasstraub2@web.de> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* migration: provide an error message to migration_cancel()Laurent Vivier2021-11-031-2/+1
| | | | | | | | | | This avoids to call migrate_get_current() in the caller function whereas migration_cancel() already needs the pointer to the current migration state. Signed-off-by: Laurent Vivier <lvivier@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* migration/ram: Handle RAMBlocks with a RamDiscardManager on background snapshotsDavid Hildenbrand2021-11-011-2/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We already don't ever migrate memory that corresponds to discarded ranges as managed by a RamDiscardManager responsible for the mapped memory region of the RAMBlock. virtio-mem uses this mechanism to logically unplug parts of a RAMBlock. Right now, we still populate zeropages for the whole usable part of the RAMBlock, which is undesired because: 1. Even populating the shared zeropage will result in memory getting consumed for page tables. 2. Memory backends without a shared zeropage (like hugetlbfs and shmem) will populate an actual, fresh page, resulting in an unintended memory consumption. Discarded ("logically unplugged") parts have to remain discarded. As these pages are never part of the migration stream, there is no need to track modifications via userfaultfd WP reliably for these parts. Further, any writes to these ranges by the VM are invalid and the behavior is undefined. Note that Linux only supports userfaultfd WP on private anonymous memory for now, which usually results in the shared zeropage getting populated. The issue will become more relevant once userfaultfd WP supports shmem and hugetlb. Acked-by: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* migration/ram: Factor out populating pages readable in ↵David Hildenbrand2021-11-011-13/+22
| | | | | | | | | | | | | | | | | | | ram_block_populate_pages() Let's factor out prefaulting/populating to make further changes easier to review and add a comment what we are actually expecting to happen. While at it, use the actual page size of the ramblock, which defaults to qemu_real_host_page_size for anonymous memory. Further, rename ram_block_populate_pages() to ram_block_populate_read() as well, to make it clearer what we are doing. In the future, we might want to use MADV_POPULATE_READ to speed up population. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* migration: Simplify alignment and alignment checksDavid Hildenbrand2021-11-011-1/+1
| | | | | | | | | | | Let's use QEMU_ALIGN_DOWN() and friends to make the code a bit easier to read. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* migration/postcopy: Handle RAMBlocks with a RamDiscardManager on the destinationDavid Hildenbrand2021-11-011-0/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, when someone (i.e., the VM) accesses discarded parts inside a RAMBlock with a RamDiscardManager managing the corresponding mapped memory region, postcopy will request migration of the corresponding page from the source. The source, however, will never answer, because it refuses to migrate such pages with undefined content ("logically unplugged"): the pages are never dirty, and get_queued_page() will consequently skip processing these postcopy requests. Especially reading discarded ("logically unplugged") ranges is supposed to work in some setups (for example with current virtio-mem), although it barely ever happens: still, not placing a page would currently stall the VM, as it cannot make forward progress. Let's check the state via the RamDiscardManager (the state e.g., of virtio-mem is migrated during precopy) and avoid sending a request that will never get answered. Place a fresh zero page instead to keep the VM working. This is the same behavior that would happen automatically without userfaultfd being active, when accessing virtual memory regions without populated pages -- "populate on demand". For now, there are valid cases (as documented in the virtio-mem spec) where a VM might read discarded memory; in the future, we will disallow that. Then, we might want to handle that case differently, e.g., warning the user that the VM seems to be mis-behaving. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* migration/ram: Handle RAMBlocks with a RamDiscardManager on the migration sourceDavid Hildenbrand2021-11-011-0/+77
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't want to migrate memory that corresponds to discarded ranges as managed by a RamDiscardManager responsible for the mapped memory region of the RAMBlock. The content of these pages is essentially stale and without any guarantees for the VM ("logically unplugged"). Depending on the underlying memory type, even reading memory might populate memory on the source, resulting in an undesired memory consumption. Of course, on the destination, even writing a zeropage consumes memory, which we also want to avoid (similar to free page hinting). Currently, virtio-mem tries achieving that goal (not migrating "unplugged" memory that was discarded) by going via qemu_guest_free_page_hint() - but it's hackish and incomplete. For example, background snapshots still end up reading all memory, as they don't do bitmap syncs. Postcopy recovery code will re-add previously cleared bits to the dirty bitmap and migrate them. Let's consult the RamDiscardManager after setting up our dirty bitmap initially and when postcopy recovery code reinitializes it: clear corresponding bits in the dirty bitmaps (e.g., of the RAMBlock and inside KVM). It's important to fixup the dirty bitmap *after* our initial bitmap sync, such that the corresponding dirty bits in KVM are actually cleared. As colo is incompatible with discarding of RAM and inhibits it, we don't have to bother. Note: if a misbehaving guest would use discarded ranges after migration started we would still migrate that memory: however, then we already populated that memory on the migration source. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* memory: make global_dirty_tracking a bitmaskHyman Huang(黄勇)2021-11-011-4/+11
| | | | | | | | | | | | | | | | | | | | | | | since dirty ring has been introduced, there are two methods to track dirty pages of vm. it seems that "logging" has a hint on the method, so rename the global_dirty_log to global_dirty_tracking would make description more accurate. dirty rate measurement may start or stop dirty tracking during calculation. this conflict with migration because stop dirty tracking make migration leave dirty pages out then that'll be a problem. make global_dirty_tracking a bitmask can let both migration and dirty rate measurement work fine. introduce GLOBAL_DIRTY_MIGRATION and GLOBAL_DIRTY_DIRTY_RATE to distinguish what current dirty tracking aims for, migration or dirty rate. Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn> Message-Id: <9c9388657cfa0301bd2c1cfa36e7cf6da4aeca19.1624040308.git.huangy81@chinatelecom.cn> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* migration/ram: Don't passs RAMState to ↵David Hildenbrand2021-10-191-8/+5
| | | | | | | | | | | | migration_clear_memory_region_dirty_bitmap_*() The parameter is unused, let's drop it. Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
* migration: clear the memory region dirty bitmap when skipping free pagesWei Wang2021-07-261-18/+56
| | | | | | | | | | | | | | | | When skipping free pages to send, their corresponding dirty bits in the memory region dirty bitmap need to be cleared. Otherwise the skipped pages will be sent in the next round after the migration thread syncs dirty bits from the memory region dirty bitmap. Cc: David Hildenbrand <david@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Reported-by: David Hildenbrand <david@redhat.com> Signed-off-by: Wei Wang <wei.w.wang@intel.com> Message-Id: <20210722083055.23352-1-wei.w.wang@intel.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: Teach QEMUFile to be QIOChannel-awarePeter Xu2021-07-261-1/+1
| | | | | | | | | | | | | | | | | | | | migration uses QIOChannel typed qemufiles. In follow up patches, we'll need the capability to identify this fact, so that we can get the backing QIOChannel from a QEMUFile. We can also define types for QEMUFile but so far since we only need to be able to identify QIOChannel, introduce a boolean which is simpler. Introduce another helper qemu_file_get_ioc() to return the ioc backend of a qemufile if has_ioc is set. No functional change. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20210722175841.938739-5-peterx@redhat.com> Reviewed-by: Lukas Straub <lukasstraub2@web.de> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: Make from_dst_file accesses thread-safePeter Xu2021-07-261-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | Accessing from_dst_file is potentially racy in current code base like below: if (s->from_dst_file) do_something(s->from_dst_file); Because from_dst_file can be reset right after the check in another thread (rp_thread). One example is migrate_fd_cancel(). Use the same qemu_file_lock to protect it too, just like to_dst_file. When it's safe to access without lock, comment it. There's one special reference in migration_thread() that can be replaced by the newly introduced rp_thread_created flag. Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Lukas Straub <lukasstraub2@web.de> Message-Id: <20210722175841.938739-3-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> with Peter's fixup
* migration: Move bitmap_mutex out of migration_bitmap_clear_dirty()Peter Xu2021-07-131-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Taking the mutex every time for each dirty bit to clear is too slow, especially we'll take/release even if the dirty bit is cleared. So far it's only used to sync with special cases with qemu_guest_free_page_hint() against migration thread, nothing really that serious yet. Let's move the lock to be upper. There're two callers of migration_bitmap_clear_dirty(). For migration, move it into ram_save_iterate(). With the help of MAX_WAIT logic, we'll only run ram_save_iterate() for no more than 50ms-ish time, so taking the lock once there at the entry. It also means any call sites to qemu_guest_free_page_hint() can be delayed; but it should be very rare, only during migration, and I don't see a problem with it. For COLO, move it up to colo_flush_ram_cache(). I think COLO forgot to take that lock even when calling ramblock_sync_dirty_bitmap(), where another example is migration_bitmap_sync() who took it right. So let the mutex cover both the ramblock_sync_dirty_bitmap() and migration_bitmap_clear_dirty() calls. It's even possible to drop the lock so we use atomic operations upon rb->bmap and the variable migration_dirty_pages. I didn't do it just to still be safe, also not predictable whether the frequent atomic ops could bring overhead too e.g. on huge vms when it happens very often. When that really comes, we can keep a local counter and periodically call atomic ops. Keep it simple for now. Cc: Wei Wang <wei.w.wang@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Hailiang Zhang <zhang.zhanghailiang@huawei.com> Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Cc: Juan Quintela <quintela@redhat.com> Cc: Leonardo Bras Soares Passos <lsoaresp@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20210630200805.280905-1-peterx@redhat.com> Reviewed-by: Wei Wang <wei.w.wang@intel.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: fix typo in mig_throttle_guest_down commentOlaf Hering2021-07-091-1/+1
| | | | | | | | | | | Fixes commit 3d0684b2ad82a5dde68e3f08b0d7786dccaf619c ("ram: Update all functions comments") Signed-off-by: Olaf Hering <olaf@aepfle.de> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-Id: <20210708162159.18045-1-olaf@aepfle.de> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
* memory: Introduce RAM_NORESERVE and wire it up in qemu_ram_mmap()David Hildenbrand2021-06-151-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's introduce RAM_NORESERVE, allowing mmap'ing with MAP_NORESERVE. The new flag has the following semantics: " RAM is mmap-ed with MAP_NORESERVE. When set, reserving swap space (or huge pages if applicable) is skipped: will bail out if not supported. When not set, the OS will do the reservation, if supported for the memory type. " Allow passing it into: - memory_region_init_ram_nomigrate() - memory_region_init_resizeable_ram() - memory_region_init_ram_from_file() ... and teach qemu_ram_mmap() and qemu_anon_ram_alloc() about the flag. Bail out if the flag is not supported, which is the case right now for both, POSIX and win32. We will add Linux support next and allow specifying RAM_NORESERVE via memory backends. The target use case is virtio-mem, which dynamically exposes memory inside a large, sparse memory area to the VM. Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Acked-by: Eduardo Habkost <ehabkost@redhat.com> for memory backend and machine core Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20210510114328.21835-9-david@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* migration/ram: Use offset_in_ramblock() in range checksDavid Hildenbrand2021-05-131-5/+5
| | | | | | | | | | We never read or write beyond the used_length of memory blocks when migrating. Make this clearer by using offset_in_ramblock() consistently. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20210429112708.12291-11-david@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration/ram: Handle RAM block resizes during postcopyDavid Hildenbrand2021-05-131-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | Resizing while migrating is dangerous and does not work as expected. The whole migration code works with the usable_length of a ram block and does not expect this value to change at random points in time. In the case of postcopy, relying on used_length is racy as soon as the guest is running. Also, when used_length changes we might leave the uffd handler registered for some memory regions, reject valid pages when migrating and fail when sending the recv bitmap to the source. Resizing can be trigger *after* (but not during) a reset in ACPI code by the guest - hw/arm/virt-acpi-build.c:acpi_ram_update() - hw/i386/acpi-build.c:acpi_ram_update() Let's remember the original used_length in a separate variable and use it in relevant postcopy code. Make sure to update it when we resize during precopy, when synchronizing the RAM block sizes with the source. Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20210429112708.12291-9-david@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration/ram: Simplify host page handling in ram_load_postcopy()David Hildenbrand2021-05-131-23/+32
| | | | | | | | | | | | | | Add two new helper functions. This will come in come handy once we want to handle ram block resizes while postcopy is active. Note that ram_block_from_stream() will already print proper errors. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20210429112708.12291-8-david@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> dgilbert: Added brackets in host_page_from_ram_block_offset to cause uintptr_t to cast the sum, to fix armhf-cross build
* migration/ram: Discard RAM when growing RAM blocks after ↵David Hildenbrand2021-05-131-0/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | ram_postcopy_incoming_init() In case we grow our RAM after ram_postcopy_incoming_init() (e.g., when synchronizing the RAM block state with the migration source), the resized part would not get discarded. Let's perform that when being notified about a resize while postcopy has been advised, but is not listening yet. With precopy, the process is as following: 1. VM created - RAM blocks are created 2. Incomming migration started - Postcopy is advised - All pages in RAM blocks are discarded 3. Precopy starts - RAM blocks are resized to match the size on the migration source. - RAM pages from precopy stream are loaded - Uffd handler is registered, postcopy starts listening 4. Guest started, postcopy running - Pagefaults get resolved, pages get placed Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20210429112708.12291-7-david@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration/ram: Handle RAM block resizes during precopyDavid Hildenbrand2021-05-131-0/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | Resizing while migrating is dangerous and does not work as expected. The whole migration code works on the usable_length of ram blocks and does not expect this to change at random points in time. In the case of precopy, the ram block size must not change on the source, after syncing the RAM block list in ram_save_setup(), so as long as the guest is still running on the source. Resizing can be trigger *after* (but not during) a reset in ACPI code by the guest - hw/arm/virt-acpi-build.c:acpi_ram_update() - hw/i386/acpi-build.c:acpi_ram_update() Use the ram block notifier to get notified about resizes. Let's simply cancel migration and indicate the reason. We'll continue running on the source. No harm done. Update the documentation. Postcopy will be handled separately. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20210429112708.12291-5-david@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Manual merge
* migration/ram: Optimize ram_save_host_page()Kunkun Jiang2021-05-131-20/+19
| | | | | | | | | | | | | | | | | | | Starting from pss->page, ram_save_host_page() will check every page and send the dirty pages up to the end of the current host page or the boundary of used_length of the block. If the host page size is a huge page, the step "check" will take a lot of time. It will improve performance to use migration_bitmap_find_dirty(). Tested on Kunpeng 920; VM parameters: 1U 4G (page size 1G) The time of ram_save_host_page() in the last round of ram saving: before optimize: 9250us after optimize: 34us Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com> Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> Reviewed-by: Peter Xu <peterx@redhat.com> Message-Id: <20210316125716.1243-3-jiangkunkun@huawei.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration/ram: Reduce unnecessary rate limitingKunkun Jiang2021-05-131-2/+7
| | | | | | | | | | | | | When the host page is a huge page and something is sent in the current iteration, migration_rate_limit() should be executed. If not, it can be omitted. Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com> Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> Reviewed-by: David Edmondson <david.edmondson@oracle.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20210316125716.1243-2-jiangkunkun@huawei.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migrate/ram: remove "ram_bulk_stage" and "fpo_enabled"David Hildenbrand2021-05-131-61/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The bulk stage is kind of weird: migration_bitmap_find_dirty() will indicate a dirty page, however, ram_save_host_page() will never save it, as migration_bitmap_clear_dirty() detects that it is not dirty. We already fill the bitmap in ram_list_init_bitmaps() with ones, marking everything dirty - it didn't used to be that way, which is why we needed an explicit first bulk stage. Let's simplify: make the bitmap the single source of thuth. Explicitly handle the "xbzrle_enabled after first round" case. Regarding XBZRLE (implicitly handled via "ram_bulk_stage = false" right now), there is now a slight change in behavior: - Colo: When starting, it will be disabled (was implicitly enabled) until the first round actually finishes. - Free page hinting: When starting, XBZRLE will be disabled (was implicitly enabled) until the first round actually finished. - Snapshots: When starting, XBZRLE will be disabled. We essentially only do a single run, so I guess it will never actually get disabled. Postcopy seems to indirectly disable it in ram_save_page(), so there shouldn't be really any change. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Juan Quintela <quintela@redhat.com> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Cc: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20210216105039.40680-1-david@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* Do not include cpu.h if it's not really necessaryThomas Huth2021-05-021-1/+0
| | | | | | | | Stop including cpu.h in files that don't need it. Signed-off-by: Thomas Huth <thuth@redhat.com> Message-Id: <20210416171314.2074665-4-thuth@redhat.com> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
* Do not include sysemu/sysemu.h if it's not really necessaryThomas Huth2021-05-021-1/+0
| | | | | | | | Stop including sysemu/sysemu.h in files that don't need it. Signed-off-by: Thomas Huth <thuth@redhat.com> Message-Id: <20210416171314.2074665-2-thuth@redhat.com> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
* migration: Rename 'bs' to 'block' in background snapshot codeAndrey Gruzdev2021-04-071-42/+44
| | | | | | | | | | | Rename 'bs' to commonly used 'block' in migration/ram.c background snapshot code. Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com> Reported-by: David Hildenbrand <david@redhat.com> Message-Id: <20210401092226.102804-5-andrey.gruzdev@virtuozzo.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: Pre-fault memory before starting background snasphotAndrey Gruzdev2021-04-071-0/+49
| | | | | | | | | | | | | | | | | | | | | This commit solves the issue with userfault_fd WP feature that background snapshot is based on. For any never poluated or discarded memory page, the UFFDIO_WRITEPROTECT ioctl() would skip updating PTE for that page, thereby loosing WP setting for it. So we need to pre-fault pages for each RAM block to be protected before making a userfault_fd wr-protect ioctl(). Fixes: 278e2f551a095b234de74dca9c214d5502a1f72c (migration: support UFFD write fault processing in ram_save_iterate()) Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com> Reported-by: David Hildenbrand <david@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Message-Id: <20210401092226.102804-4-andrey.gruzdev@virtuozzo.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> dgilbert: Bodged ifdef __linux__ on ram_write_tracking_prepare, should really go in a stub
* migrate: remove QMP/HMP commands for speed, downtime and cache sizeDaniel P. Berrangé2021-03-181-1/+1
| | | | | | | | | | | | The generic 'migrate_set_parameters' command handle all types of param. Only the QMP commands were documented in the deprecations page, but the rationale for deprecating applies equally to HMP, and the replacements exist. Furthermore the HMP commands are just shims to the QMP commands, so removing the latter breaks the former unless they get re-implemented. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
* migration: Replaced qemu_mutex_lock calls with QEMU_LOCK_GUARDMahmoud Mandour2021-03-151-4/+2
| | | | | | | | | | | Replaced various qemu_mutex_lock calls and their respective qemu_mutex_unlock calls with QEMU_LOCK_GUARD macro. This simplifies the code by eliminating the respective qemu_mutex_unlock calls. Signed-off-by: Mahmoud Mandour <ma.mandourr@gmail.com> Message-Id: <20210311031538.5325-7-ma.mandourr@gmail.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: only check page size match if RAM postcopy is enabledStefan Reiter2021-02-081-1/+1
| | | | | | | | | | | | | Postcopy may also be advised for dirty-bitmap migration only, in which case the remote page size will not be available and we'll instead read bogus data, blocking migration with a mismatch error if the VM uses hugepages. Fixes: 58110f0acb ("migration: split common postcopy out of ram postcopy") Signed-off-by: Stefan Reiter <s.reiter@proxmox.com> Message-Id: <20210204163522.13291-1-s.reiter@proxmox.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: Clean up signed vs. unsigned XBZRLE cache-sizeMarkus Armbruster2021-02-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | 73af8dd8d7 "migration: Make xbzrle_cache_size a migration parameter" (v2.11.0) made the new parameter unsigned (QAPI type 'size', uint64_t in C). It neglected to update existing code, which continues to use int64_t. migrate_xbzrle_cache_size() returns the new parameter. Adjust its return type. QMP query-migrate-cache-size returns migrate_xbzrle_cache_size(). Adjust its return type. migrate-set-parameters passes the new parameter to xbzrle_cache_resize(). Adjust its parameter type. xbzrle_cache_resize() passes it on to cache_init(). Adjust its parameter type. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20210202141734.2488076-3-armbru@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: support UFFD write fault processing in ram_save_iterate()Andrey Gruzdev2021-02-081-29/+295
| | | | | | | | | | | | | | | | | | | | | | | | In this particular implementation the same single migration thread is responsible for both normal linear dirty page migration and procesing UFFD page fault events. Processing write faults includes reading UFFD file descriptor, finding respective RAM block and saving faulting page to the migration stream. After page has been saved, write protection can be removed. Since asynchronous version of qemu_put_buffer() is expected to be used to save pages, we also have to flush migraion stream prior to un-protecting saved memory range. Write protection is being removed for any previously protected memory chunk that has hit the migration stream. That's valid for pages from linear page scan along with write fault pages. Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com> Acked-by: Peter Xu <peterx@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20210129101407.103458-4-andrey.gruzdev@virtuozzo.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> fixup pagefault.address cast for 32bit
* migration: introduce 'background-snapshot' migration capabilityAndrey Gruzdev2021-02-081-0/+21
| | | | | | | | | | | | | Add new capability to 'qapi/migration.json' schema. Update migrate_caps_check() to validate enabled capability set against introduced one. Perform checks for required kernel features and compatibility with guest memory backends. Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com> Reviewed-by: Peter Xu <peterx@redhat.com> Acked-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20210129101407.103458-2-andrey.gruzdev@virtuozzo.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration/ram: Fix hexadecimal format string specifierPhilippe Mathieu-Daudé2020-11-121-1/+1
| | | | | | | | | | | | The '%u' conversion specifier is for decimal notation. When prefixing a format with '0x', we want the hexadecimal specifier ('%x'). Inspired-by: Dov Murik <dovmurik@linux.vnet.ibm.com> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20201103112558.2554390-5-philmd@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* Reduce the time of checkpoint for COLORao, Lei2020-11-111-1/+13
| | | | | | | | | | | | | | we should set ram_bulk_stage to false after ram_state_init, otherwise the bitmap will be unused in migration_bitmap_find_dirty. all pages in ram cache will be flushed to the ram of secondary guest for each checkpoint. Signed-off-by: Lei Rao <lei.rao@intel.com> Signed-off-by: Derek Su <dereksu@qnap.com> Signed-off-by: Zhang Chen <chen.zhang@intel.com> Reviewed-by: Li Zhijian <lizhijian@cn.fujitsu.com> Reviewed-by: Zhang Chen <chen.zhang@intel.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
* migration: Do not initialise statics and globals to 0 or NULLBihong Yu2020-10-261-1/+1
| | | | | | | | | Signed-off-by: Bihong Yu <yubihong@huawei.com> Reviewed-by: Chuan Zheng <zhengchuan@huawei.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <1603163448-27122-7-git-send-email-yubihong@huawei.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: Add braces {} for if statementBihong Yu2020-10-261-2/+4
| | | | | | | | | Signed-off-by: Bihong Yu <yubihong@huawei.com> Reviewed-by: Chuan Zheng <zhengchuan@huawei.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <1603163448-27122-6-git-send-email-yubihong@huawei.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: Add spaces around operatorBihong Yu2020-10-261-1/+1
| | | | | | | | | Signed-off-by: Bihong Yu <yubihong@huawei.com> Reviewed-by: Chuan Zheng <zhengchuan@huawei.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <1603163448-27122-4-git-send-email-yubihong@huawei.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration: Don't use '#' flag of printf formatBihong Yu2020-10-261-2/+2
| | | | | | | | | Signed-off-by: Bihong Yu <yubihong@huawei.com> Reviewed-by: Chuan Zheng <zhengchuan@huawei.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Message-Id: <1603163448-27122-3-git-send-email-yubihong@huawei.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration/dirtyrate: move RAMBLOCK_FOREACH_MIGRATABLE into ram.hChuan Zheng2020-09-251-10/+1
| | | | | | | | | | | | RAMBLOCK_FOREACH_MIGRATABLE is need in dirtyrate measure, move the existing definition up into migration/ram.h Signed-off-by: Chuan Zheng <zhengchuan@huawei.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: David Edmondson <david.edmondson@oracle.com> Reviewed-by: Li Qiang <liq3ea@gmail.com> Message-Id: <1600237327-33618-6-git-send-email-zhengchuan@huawei.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
* migration/: fix some comment spelling errorszhaolichang2020-09-171-5/+5
| | | | | | | | | | | I found that there are many spelling errors in the comments of qemu, so I used the spellcheck tool to check the spelling errors and finally found some spelling errors in the migration folder. Signed-off-by: zhaolichang <zhaolichang@huawei.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-Id: <20200917075029.313-3-zhaolichang@huawei.com> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
* cpu-throttle: new module, extracted from cpus.cClaudio Fontana2020-07-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | | move the vcpu throttling functionality into its own module. This functionality is not specific to any accelerator, and it is used currently by migration to slow down guests to try to have migrations converge, and by the cocoa MacOS UI to throttle speed. cpu-throttle contains the controls to adjust and inspect throttle settings, start (set) and stop vcpu throttling, and the throttling function itself that is run periodically on vcpus to make them take a nap. Execution of the throttling function on all vcpus is triggered by a timer, registered at module initialization. No functionality change. Signed-off-by: Claudio Fontana <cfontana@suse.de> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20200629093504.3228-3-cfontana@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* migration: Count new_dirty instead of real_dirtyKeqian Zhu2020-07-031-3/+5
| | | | | | | | | | | | | | real_dirty_pages becomes equal to total ram size after dirty log sync in ram_init_bitmaps, the reason is that the bitmap of ramblock is initialized to be all set, so old path counts them as "real dirty" at beginning. This causes wrong dirty rate and false positive throttling. Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com> Message-Id: <20200622032037.31112-1-zhukeqian1@huawei.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>