Merge remote-tracking branch...

Merge remote-tracking branch 'remotes/juanquintela/tags/migration-20211031-pull-request' into staging

Migration Pull request

Hi

this includes pending bits of migration patches.

- virtio-mem support by David Hildenbrand
- dirtyrate improvements by Hyman Huang
- fix rdma wrid by Li Zhijian
- dump-guest-memory fixes by Peter Xu

Pleas apply.

Thanks, Juan.

# gpg: Signature made Mon 01 Nov 2021 06:03:44 PM EDT
# gpg:                using RSA key 1899FF8EDEBF58CCEE034B82F487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>" [full]
# gpg:                 aka "Juan Quintela <quintela@trasno.org>" [full]

* remotes/juanquintela/tags/migration-20211031-pull-request:
  migration/dirtyrate: implement dirty-bitmap dirtyrate calculation
  memory: introduce total_dirty_pages to stat dirty pages
  migration/ram: Handle RAMBlocks with a RamDiscardManager on background snapshots
  migration/ram: Factor out populating pages readable in ram_block_populate_pages()
  migration: Simplify alignment and alignment checks
  migration/postcopy: Handle RAMBlocks with a RamDiscardManager on the destination
  virtio-mem: Drop precopy notifier
  migration/ram: Handle RAMBlocks with a RamDiscardManager on the migration source
  virtio-mem: Implement replay_discarded RamDiscardManager callback
  memory: Introduce replay_discarded callback for RamDiscardManager
  dump-guest-memory: Block live migration
  migration: Add migrate_add_blocker_internal()
  migration: Make migration blocker work for snapshots too
  migration/dirtyrate: implement dirty-ring dirtyrate calculation
  migration/dirtyrate: move init step of calculation to main thread
  migration/dirtyrate: adjust order of registering thread
  migration/dirtyrate: introduce struct and adjust DirtyRateStat
  memory: make global_dirty_tracking a bitmask
  KVM: introduce dirty_pages and kvm_dirty_ring_enabled
  migration/rdma: Fix out of order wrid

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>