Two small patches from the same investigation of the postcopy
shared-page-fault path:

- Patch 1 documents that multifd and postcopy-ram can be enabled
  together since the 10.1 release, and how the two features interact.

- Patch 2 resolves the "TODO: support blocktime tracking" in
  postcopy_request_shared_page() by reporting faults taken by memory
  sharing processes (e.g. a vhost-user backend) with a foreign tid, so
  they show up in the latency reports without polluting the vCPU
  blocktime ones.

The patches are independent of each other; patch 2 was verified with a
vhost-user postcopy migration, where the shared faults now show up in
the latency reports and the page request accounting stays balanced.

Bin Guo (2):
  docs/migration: document that postcopy can be used with multifd
  migration/postcopy: account faults taken by memory sharing processes

 docs/devel/migration/postcopy.rst | 26 ++++++++++++++++++++++++++
 migration/postcopy-ram.c          | 26 ++++++++++++++++----------
 migration/postcopy-ram.h          | 10 ++++++++++
 3 files changed, 52 insertions(+), 10 deletions(-)

-- 
2.50.1 (Apple Git-155)